Details of a Researcher - Ikaga, Toshiharu

Papers - Ikaga, Toshiharu

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THE IMPACT OF INDOOR THERMAL ENVIRONMENT IN WINTER ON DETERIORATION OF CARE LEVEL IN NURSING HOME RESIDENTS A field survey on indoor thermal environment of nursing home and resident’s care condition

Yukie HAYASHI, Toshiharu IKAGA, Shintaro ANDO and Tanji HOSHI

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 83 ( 745 ) 225 - 233 2018.03

Research paper (scientific journal), Joint Work, Accepted, ISSN 1348-0685

The Japanese population is ageing, and currently has the world's highest proportion of elderly people. As one consequence, the number of residents in nursing homes is increasing. The Ministry of Health, Labour and Welfare of Japan has identified preventing a need for care as an important aim. The ministry defines “care prevention” in two parts: preventing a care-requiring condition from arising and, when a care-requiring condition already exists, aiming to improve while preventing deterioration. However, mean care level in nursing homes is still increasing, and existing care-prevention strategies are not enough to prevent future increase.
A field survey was conducted to clarify the effect of indoor thermal environment on the care-requiring condition of residents in nursing homes. Twenty private residential-nursing homes, located in the Osaka, Kyoto, Nara and Hyogo prefectures of Japan, were included in this study. Room temperature and relative humidity were measured over approximately 4 weeks in private rooms, the dining room and other rooms of each facility at 20-min intervals in winter 2015. Additionally, questionnaire surveys were conducted twice, in winter 2015 and winter 2016. In the questionnaire, care level and date of certification of care needs was investigated for all care certifications in effect after occupancy until the time of the survey.
Most facilities had a relatively warm but dry indoor environment. Fifteen facilities were classified into two groups (warm and cold) based on measured room temperature and two groups (moist and dry) based on measured relative humidity. The Kaplan-Meier method was used to analyse the speed of deterioration (i.e., intensification) of required care level. Residents in the dry facility deteriorated with respect to care level more quickly than residents in the moist facility. In contrast, there was no significant difference according to room temperature. Many factors influence care requirements, including not only the indoor thermal environment but also individual attributes, injury and diseases. To assess these influences, multivariate analysis was carried out.
Cox proportional hazards regression analysis was used for multivariate analysis to assess the effect of indoor thermal environment on the care-requiring condition of residents in nursing homes. Two questions were evaluated: “Did the care level deteriorate?” and “If so, how long did it take for care level to deteriorate?” The analysis result showed the cold group and the dry group having a higher risk of deterioration of care level. Furthermore, residents in facilities that were both warm and moist had the lowest risk. This result suggests that both temperature and humidity are important for care prevention.
The study results are expected to contribute to improvement in indoor thermal environments and to care-prevention among residents of nursing homes.

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高断熱住宅への住み替えによる冬季の睡眠の質への影響

Wataru UMISHIO, Toshiharu IKAGA and Chika OHASHI

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 82 ( 736 ) 513 - 523 2017.06

Research paper (scientific journal), Joint Work, Accepted, ISSN 1348-0685

This study aimed to clarify the impact of indoor thermal environment on sleep quality. Follow-up investigations on sleep quality (sleep efficiency, amount of deep sleep, sleep latency, and number of nighttime awakenings) and indoor temperature were conducted in winter (2014–2016) before and after moving to houses with high thermal insulation performance. Multiple linear regression analysis showed that
sleep efficiency increased by 0.73% per 1 °C increase in indoor temperature during sleep. Increased indoor temperature also improved the number of nighttime awakenings.

Lower Physical Performance in Colder Seasons and Colder Houses: Evidence from a Field Study on Older People Living in the Community

Yukie Hayashi, Steven M. Schmidt, Agneta Malmgren Fänge, Tanji Hoshi and Toshiharu Ikaga

International Journal of Environmental Research and Public Health (MDPI) 14 ( 651 ) 1 - 9 2017.06

Research paper (scientific journal), Joint Work, Accepted, ISSN 1660-4601

The aim of this paper was to explore the effect of seasonal temperature differences and cold indoor environment in winter on the physical performance of older people living in the community based on a field study. We recruited 162 home-dwelling older people from a rehabilitation facility in the Osaka prefecture, Japan; physical performance data were available from 98/162 (60.5%). At the same time, for some participants, a questionnaire survey and a measurement of the indoor temperature of individual houses were conducted. The analysis showed that there were seasonal trends in the physical performance of older people and that physical performance was worse in the winter compared with the autumn. Furthermore, people living in colder houses had worse physical performance. The findings indicate that keeping the house warm in the winter can help to maintain physical performance.

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Proposal of an evaluation method for resilience improvements considering lifeline supply stoppages: Evaluation of monetary value for resilience improvements by introducing a community energy system

Kaichi Otsuka, Toshiharu Ikaga, Shuzo Murakami, Ryota Kuzuki, Takahiro Kawayoke

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 82 ( 735 ) 471 - 479 2017.05

Research paper (scientific journal), Joint Work, Accepted, ISSN 1348-0685

In urban areas where population and city functions are aggregated, there are calls for the construction of business continuity districts, in which energy supply is secured in times of disaster. A decentralized and self-reliant community-level energy network is expected to contribute to improving resilience and regional vitalization, as well as to reducing carbon emissions. However, the initial investment is high and the stakeholders involved are diverse, creating potential obstacles to the introduction of such an energy network because the necessary measures are of larger scale than a simple construction project. Prior studies have shown the need for accurate recognition of non-energy benefits (NEBs) in addition to energy benefits such as energy cost savings. Moreover, evaluation methods for various co-benefits have been proposed. Yet, NEBs accrued through risk reduction have not been evaluated with respect to temporal changes in business and daily life activities associated with lifeline utilities such as electricity, water, and gas.
In this study, we conducted a questionnaire survey of city residents and non-manufacturing workers. Using the data from the questionnaire, we developed an evaluation method for improvements in resilience. In addition, we verified the effect of improving resilience through a case study of a real urban district and a housing complex district.
The results of this research are summarized below.
(1) Proposal of an evaluation method for resilience in the business sector
In the questionnaire survey, we asked non-manufacturing workers about the effect on business activities of lifeline stoppages (electricity, water, and gas) and derived a “Resiliency Factor” according to the type of business. Then, we proposed a method for resilience improvements based on Resiliency Factor and a recovery curve for business activity according to the lifeline stoppage time, and we plotted a recovery curve for business activity according to the lifeline stoppage time. In addition, we expressed the resilience improvement in the business sector in monetary terms.
(2) Proposal of an evaluation method for resilience in the housing sector
In the questionnaire survey, we asked residents about the losses incurred as a result of electric power failure. Then, we derived a basic unit of loss due to electric power failure according to stoppage time. This basic unit was then used in an estimation model considering housing type and location to assess resilience improvements in the housing sector in monetary terms.
(3) Case study
We performed a case study of the effect on resilience of introducing a community energy network under the assumption of a large-scale earthquake. In the evaluation, the Tamachi Station district was taken as an example of urban areas and the Hamamidaira housing complex district was taken as an example of areas around existing housing complexes We found that by introduction of the community energy system, the Tamachi Station district would accrue NEBs of 140 million yen per year and the Hamamidaira housing complex district would accrue NEBs of 5.11 million yen per year.

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MULTIVARIATE ANALYSIS ON PHYSICAL ACTIVITY OF STUDENTS INFLUENCED BY NEIGHBORHOOD ENVIRONMENT

Kanoko NISHIKAWA Toshiharu IKAGA and Satoko OMI

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 82 ( 734 ) 317 - 325 2017.04

Research paper (scientific journal), Joint Work, Accepted, ISSN 1348-0685

The reduced ability to exercise and the increasing prevalence of overweight and obesity in students have recently become serious health concerns. Decreased physical activity in students is cited as a factor in these problems. Governmental agencies have promoted improvement of the regional environment in order to encourage physical activity in students. However, there is insufficient quantitative verification of the regional environmental factors that affect the physical activity of students. Therefore, the purpose of this study was to clarify the relationship between the regional environment and physical activity in students, using a questionnaire survey and actual measurements of physical activity.

A questionnaire survey was conducted for more than 300 teachers across 13 elementary schools to evaluate the satisfaction with the natural environment, the public security, the facilities for communication and the public facilities of each school district. Also, a measurement survey was conducted in the same public schools in Kawasaki city and data were obtained from 702 students aged 10-11 years old across 13 school districts. During a week of September to November 2014, the number of walking steps of each student was measured by a pedometer, HJ326F and HJA-350IT (OMRON).

1) Impact of the regional environment on physical activity
Using the results of a questionnaire survey and actual measurements of physical activity, we conducted the multi-level model analysis in order to clarify the impact of the regional environment on physical activity of students in taking account of individual attributes. As a result, for school regions where the satisfaction with the natural environment and the public security were high, the number of walking steps on weekdays exceeded those where the satisfaction was lower. According to the multi-level model analysis, the regional average number of steps increased by about 300 for every 1pt increase in the satisfaction score of the natural environment and the public security.

2) Relation between satisfaction with neighborhood environments and land use
Although we examined the relationship between the satisfaction with neighborhood environment and physical activity in students, a concrete factor which increases such satisfaction with regional environment was unclear. Therefore, we carried out a correlation analysis between the satisfaction score of neighborhood environments and the land use and the zoning of the regions. The satisfaction score of the natural environment of a region was correlated with the proportion of a forested region. We also examined the negative correlation between the satisfaction with natural environment and the proportion of a dense low storied building area.

In conclusion, the result of this study confirmed a relationship between regional environment and physical activity in students and showed the significance value of the natural environment, the public security and the facilities for communication to encourage physical activity in students.

Sudden Death Phenomenon While Bathing in Japan ― Mortality Data ―

Masaru Suzuki, Takuro Shimbo, Toshiharu Ikaga and Shingo Hori

Circulation Journal (JAPANESE CIRCULATION SOC) 81 ( 8 ) 1144 - 1149 2017.04

Research paper (scientific journal), Joint Work, Accepted, ISSN 1346-9843

BACKGROUND: Bath-related sudden cardiac arrest frequently occurs in Japan, but the mortality data have not been sufficiently reported.Methods and Results:This prospective cross-sectional observational study was conducted in the Tokyo Metropolis, Saga Prefecture and Yamagata Prefecture between October 2012 and March 2013 (i.e., in winter). We investigated the data for all occurrences in these areas for which the emergency medical system needed to be activated because of an accident or acute illness related to bathing. Emergency personnel enrolled the event when activation of the emergency medical system was related to bathing. Of the 4,599 registered bath-related events, 1,527 (33%) were identified as bath-related cardiac arrest events. Crude mortality (no. deaths per 100,000) during the observational period was 10.0 in Tokyo, 11.6 in Yamagata and 8.5 in Saga. According to the mortality data for age and sex, the estimated number of bath-related deaths nationwide was 13,369 in winter, for the 6 months from October (95% CI: 10,862-16,887). Most cardiac arrest events occurred in tubs filled with water with the face submerged in the water. This suggests that drowning plays a crucial role in the etiology of such phenomena. CONCLUSIONS: The estimated nationwide number of deaths was 13,369 (95% CI: 10,862-16,887) in winter, for the 6 months from October. Crude mortality during the winter season was 10.0 in Tokyo, 11.6 in Yamagata and 8.5 in Saga.

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EVENT HISTORY ANALYSIS OF INDOOR THERMAL ENVIRONMENT AND CARE PREVENTION OF RESIDENTS A field survey on the effect of winter indoor thermal environment on care requirements

Yukie HAYASHI, Toshiharu IKAGA, Tanji HOSHI and Shitaro ANDO

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 81 ( 729 ) 901 - 908 2016.11

Research paper (scientific journal), Joint Work, Accepted, ISSN 1348-0685

The aim of this paper is to clarify the relationship between the indoor thermal environment and care prevention. A field study comprising actual measurements, questionnaire surveys, and data collection from face sheets was conducted in 2014. Participants were classified into two groups based on frequency of feeling cold in their rooms. Age at certification of needing long-term care was compared between the groups by using survival analysis. The result was significant when the classification condition was frequency of feeling cold in their dressing rooms. The age at which half of the group acquired their certification was 76 years in the high-frequency group and 80 years in the low-frequency group.

ECONOMIC EVALUATION ON THE EFFECT OF THERMAL ENVIRONMENTAL CONTROL IN SUMMER ON SLEEP AND WORK EFFICIENCY

本多英里, 伊香賀俊治, 大平昇, 岡島慶治, 海塩渉

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 81 ( 724 ) 523 - 534 2016.06

Research paper (scientific journal), Joint Work, Accepted, ISSN 1348-0685

Reduced sleep quality is a serious problem. Previous studies have reported that the thermal environment affects sleep, and that although thermal environmental control via cooling is necessary, this increases energy consumption. Here, we conduct an economic evaluation of the impact of thermal environment control on both sleep quality and energy consumption through experiments conducted in August 2013 and 2014. Reduced sleep efficiency led to decreased work efficiency. The economic impact of improving sleep quality was much greater than that of energy consumption. This study showed importance of the improvement of the sleep quality.

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COMPARISON OF HOME BLOOD PRESSURE BEFORE-AND-AFTER MOVING TO HIGH THERMAL INSULATION PERFORMANCE HOUSES A field survey on the effect of indoor thermal environment on blood pressure in winter (Part III)

Wataru Umishio, Toshiharu Ikaga, Shitaro Ando and Kuniaki Otsuka

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 81 ( 722 ) 357 - 366 2016.04

Research paper (scientific journal), Joint Work, Accepted, ISSN 1348-0685

This study aimed to demonstrate antihypertensive effects by moving to high thermal insulation performance houses. Field surveys on home blood pressure and indoor temperature were conducted before and after moving in winter 2014 and 2015. Systolic blood pressure (SBP) decreased by 1.5 mmHg per 1 °C increase in indoor air temperature and standard deviation (SD) of SBP improved by 2.3 mmHg per 1 °C improvement in SD of indoor air temperature in a group over 125 mmHg. However, to raise indoor temperature, it is not satisfied only by moving to high thermal insulation performance houses but adequately heating a room.

Human response to the indoor environment under fluctuating temperature

Mayumi Miura and Toshiharu Ikaga

Science and Technology for the Built Environment (Taylar & Francis) 22 ( 6 ) 820 - 830 2016.03

Research paper (scientific journal), Joint Work, Accepted, ISSN 2374-4731

The effect on humans of a 6-hour long exposure to cyclic fluctuating air temperature was examined. The tested fluctuating pattern consisted of a gradual sweep-up +2.0◦C over 40 minutes and a rather abrupt sweep-down –2.0◦C over 20 minutes, within the temperature ranges of 26–28◦C and 27–29◦C. The experiment on cyclic fluctuating air temperature demonstrates that the thermal dissatisfaction rate for cyclic fluctuating air temperature control between 26◦C–28◦C is lower than that for constant air temperature control at 26◦C, while consuming less energy. Moreover, occupant stress levels measured by salivary alpha-amylase, and subjective fatigue levels under cyclic fluctuating air temperature show that similar or even lower distinct results can be achieved with fluctuating air temperature control compared with constant air temperature control.

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IMPACTS OF BEDROOM TEMPERATURE ON BLOOD PRESSURE VARIABILITY IN THE EARLY MORNING, BASED ON AMBULATORY BLOOD PRESSURE MONITORING

海塩渉, 伊香賀俊治, 大塚邦明, 安藤真太朗

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 80 ( 716 ) 867 - 876 2015.10

Research paper (scientific journal), Joint Work, Accepted, ISSN 1348-0685

Hypertension has become a serious problem in Japan, affecting one-third of the population. The Japanese government has set guidelines aimed at improving hypertension (e.g., “The first term of the National Health Promotion Movement in the Twenty-First Century” (Healthy Japan 21 (first term)). However, the improvement goal for hypertension, namely, a reduction in average systolic blood pressure by 4.2 mmHg, has remained unachieved for over a decade. This suggests a limit to the degree that hypertension can be prevented through lifestyle modification alone. Therefore, providing a healthy residential environment that is not affected by behavior changes is needed for health maintenance and promotion.
Against this background, the effects of the indoor thermal environment on blood pressure have attracted attention. It has been noted that blood pressure variability, particularly morning blood pressure surge, is affected by the indoor thermal environment. However, studies on these effects are insufficient. The purpose of this study was therefore to clarify how temperature in various rooms and at various times affects morning blood pressure surge, and to quantify effects of room temperature on blood pressure changes before and after getting out of bed.
A field survey on ambulatory blood pressure and indoor temperature was conducted in a hilly and mountainous area in Japan in winter month 2012. Ambulatory blood pressure was measured at 30-min intervals from 7 am to 10 pm and at 60-min intervals from 10 pm to 7 am for 7 days, in accordance with the “Guidelines for the clinical use of ambulatory blood pressure monitoring” of the Japanese Circulation Society, the Japanese Society of Hypertension, and the Japanese College of Cardiology. Indoor temperature at 1.1 m above the floor was measured in the living room, bedroom, bathroom, and outdoors at 10-min intervals. Additionally, a questionnaire on personal factors and housing was carried out. Details of the field survey are given in Section 2.
Participants in this study were 21 older adults (mean age 68 years (54–74 years)) with average build. As shown in Fig. 5, on the date when bedroom temperature was lowest (lowest day), morning blood pressure surge was larger by 8.1 mmHg than on the date when bedroom temperature was highest (highest day, p<0.05). This tendency was not observed for living room temperature or outdoor temperature. In addition, bedroom temperature at the time of getting out of bed, not mean temperature while sleeping or 2 h before or after getting out of bed, affects morning blood pressure surge (p<0.05) (Fig. 6).
Also, as shown from Fig. 10, the blood pressure gap between the lowest day and the highest day is larger after getting out of bed than before. This is likely because residents were covered by a blanket before getting out of bed, but were exposed to the colder environment after removing the blanket and getting out of bed.
Older adults at high risk of cardiovascular events should maintain a bedroom temperature within an appropriate range at the time of waking. These ﬁndings may have important implications for managing hypertension and preventing cardiovascular events

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EFFECT OF INDOOR THERMAL ENVIRONMENT AND INSULATION EFFICIENCY ON PHYSICAL ACTIVITY

Megumi Yanagisawa, Toshiharu Ikaga, Shintaro Ando, Kimihiro Hino, Tanji Hoshi

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 80 ( 716 ) 985 - 992 2015.10

Research paper (scientific journal), Joint Work, Accepted, ISSN 1348-0685

In recent years in Japan, the promotion of physical activity has been emphasized as a means of preventing lifestyle diseases. A large body of research has been conducted on environmental factors that influence physical activity, but much of that work deals with only the community environment, leaving the relationship between housing environment and physical activity unclear. Against this background, we aimed to clarify the effects of housing environment on physical activity.
We hypothesized that inhabitants would be hesitant to perform physical activities in cold houses during winter and that the amount of physical activity would therefore decrease. Furthermore, we hypothesized that due to the correlation between indoor thermal environment and insulation efficiency, high insulation efficiency would be effective for promoting physical activity. To test this hypothesis, we conducted a questionnaire survey and actual measurements in Niihama City in Ehime Prefecture, Japan, to examine the relationship between indoor thermal environment, insulation efficiency, and physical activity.
As shown in Table 1, the questionnaire evaluated the housing environment, degree of physical activity, lifestyle, and personal attributes. To assess the items in Table 2, which pertained to physical activity and indoor temperature, we conducted actual measurements during fall and winter. Physical activity was measured using a physical activity monitor that participates wore daily for approximately 2 weeks. Indoor temperature and humidity were measured with thermo-hygrometers installed at a height of about 1 meter in the living room, bedroom, lavatory, and corridor of each participant’s house, and measurements were recorded every 10 min for approximately 1 month.
Statistical analysis of the survey results revealed that people who perform less physical activity in winter than in fall tend to live in colder houses (Fig. 3). We then performed multiple regression analysis (stepwise selection) to examine the relation between indoor thermal environment and physical activity (Table 5), and found that after adjusting for biological factors, socioeconomic status, lifestyle , and outdoor temperature, greater physical activity was associated with higher minimum temperature of the lavatory and corridor (Table 6-9). Because the lavatory and corridor are considered representative of non-living-room spaces, where air heating is seldom used, these results indicated that warmer non-living room spaces are effective for promotion of physical activity. Lastly, high insulation efficiency can be considered effective for promotion of physical activity, as shown by the correlation between indoor thermal environment and insulation efficiency.

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THE IMPACT OF INDOOR TEMPERATURE ON HOME BLOOD PRESSURE BASED ON A MULTILEVEL MODEL A Field Survey on the Effect of Indoor Thermal Environment on Blood Pressure in Winter (Part II)

海塩渉, 伊香賀俊治, 大塚邦明, 安藤真太朗

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 80 ( 715 ) 703 - 710 2015.09

Research paper (scientific journal), Joint Work, Accepted, ISSN 1348-0685

According to Healthy Japan 21 (Second Term), reducing the average systolic blood pressure (BP) by 4 mmHg would prevent an estimated 14,000 deaths from cardiovascular disease (including 9,300 deaths from cerebrovascular disease and 4,700 deaths from ischemic heart disease) each year in Japan. Accordingly, reducing average BP is one of the country’s major public health goals. Moreover, it is recognized that individual efforts alone, such as lifestyle modification, cannot be relied on to achieve this goal. Measures are therefore needed that involve large numbers of people, such as environmental improvement (e.g., home renovation).
Against this background, some studies have looked at the effects of the indoor thermal environment on BP. Most BP data are obtained from repeated measurements in particular individuals, so an appropriate statistical method such as multilevel modeling should be applied to the data.
This study aimed to clarify the relationship between indoor thermal environment and home BP based on a multilevel model. By using this model, it is possible to elucidate both compositional and contextual effects of indoor temperature on home BP. These effects are respectively defined as the increase in BP per 1°C decrease in indoor temperature on a particular day and the increase in BP per 1°C decrease in average indoor temperature of houses.
Data were collected through field surveys in Tosa Town and Yusuhara Town, Kochi Prefecture; Nagato City, Yamaguchi Prefecture; Uenohara City, Yamanashi Prefecture; and some other areas around Japan. The surveys were conducted in winter (2012–2014). Home BP was measured by participants twice daily: before getting into bed in the evening and after getting out of bed in the morning. Indoor temperature at 1.1 m above the floor was measured in the living room, bedroom, bathroom, and dressing room at 10-min intervals. During the survey periods, participants recorded the wake time and bedtime each day in a diary. Questionnaire surveys on personal factors and housing were also distributed.
In developing the model of BP, residents who had lived in their present house for >10 years were screened and selected. The model was assumed to have a hierarchical structure in which day-level variables obtained from field measurements (e.g., BP, indoor temperature) were nested within resident-level variables obtained from questionnaire surveys (e.g., age, sex, body mass index). The objective variables were systolic BP and diastolic BP in the morning (n=3,331). Explanatory variables were the day-level and resident-level variables mentioned above.
Both compositional and contextual effects on morning BP were found to be significant. The sum of the effects was 0.57 (= compositional effect + contextual effect: 0.38 + 0.19) mmHg/°C for morning systolic BP and 0.43 (=0.20 + 0.23) mmHg/°C for morning diastolic BP. The interaction of age and temperature was significant, and indicated that the effect of indoor temperature on BP was stronger in older residents. One possibility is that the higher BP was caused not only by cold exposure on a particular day but also by ongoing residence in a cold house.
Lifestyle diseases such as hypertension result from the cumulative effects of various risk factors. The results of this study suggest that hypertension might result from the cumulative effect of coldness. Thus, maintaining an appropriate indoor temperature is important not just for older residents, who are sensitive to changes in indoor temperature and at high risk of cardiovascular events, but also for younger residents. These ﬁndings may have important implications for managing hypertension and preventing cardiovascular events.

STUDY ON BUSINESS SCHEME OF A COMMUNITY-LEVEL DECENTRALIZED AND SELF-RILIANT ENERGY NETWORK Allocation of co-benefits among stakeholders and feasibility evaluation by use of social-economic internal rate of return

工月良太, 村上周三, 伊香賀俊治, 山田航也, 川除隆広, 生田雄一, 小見山提子

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 80 ( 708 ) 169-176 2015.02

Research paper (scientific journal), Joint Work, Accepted, ISSN 1348-0685

Community-level decentralized and self-reliant energy network is expected to contribute to create a sustainable community as well
as its self-vitalization and energy resiliency. But implementation of this system requires consensus among variety of stakeholders and
long payback period, which are major hurdles. This study proposes the following concept and methods;
(1) PPP business scheme consisting of two types of actors; "community-level energy network infrastructure operating company" and
"on-site energy production and service providers"
(2) Proper re-allocation of cost and co-benefits among stakeholders by taking advantage of opportunities of adjusting tariffs, taxes,
subsidies for the purpose of equalizing each stakeholder’s B/C.

MULTIVARIATE ANALYSIS OF THE RISE IN HOME BLOOD PRESSURE BY PERSONAL FACTORS A Field Survey on the Effect of Indoor Thermal Environment on Blood Pressure in Winter

海塩渉, 伊香賀俊治, 大塚邦明, 安藤真太朗

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 79 ( 701 ) 571 - 577 2014.07

Research paper (scientific journal), Joint Work, Accepted, ISSN 1348-0685

It is expected that medical and nursing care expenses reached 45 trillion yen in 2010, and such expenses are expected to double to 92 trillion yen by 2025. An effective measure for lowering such expenditures is the prevention of cardiovascular disease, a major cause of which is hypertension. Recently, the effects of the indoor thermal environment on blood pressure have attracted attention. However, these effects have not been studied in relation to personal factors, particularly individual attributes and lifestyle. Therefore, the purpose of this research is to analyze the relation between indoor temperature and blood pressure while taking into account personal factors. Field surveys on home blood pressure, indoor temperature, and personal factors were conducted in winter 2012 and 2013. Controlling for personal factors, systolic blood pressure increased by 4.3 mmHg per 10 °C decrease in indoor air temperature. Also, a 1 °C decrease in indoor air temperature increased 1.1-fold the likelihood of a value above 135 mmHg (baseline for systolic blood pressure at home). Furthermore, the effect of indoor air temperature was stronger in residents with more severe arteriosclerosis.

INFLUENCE OF RESIDENTIAL PERFORMANCE ON RESIDENTS’ HEALTH PROMOTION Nationwide survey of environmental performance of detached houses and residents’ health status

川久保俊, 伊香賀俊治, 村上周三, 星旦二, 安藤真太朗

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 79 ( 700 ) 555-561 - 561 2014.06

Research paper (scientific journal), Joint Work, Accepted, ISSN 1348-0685

Previous studies have revealed relationships between specific residential environmental factors and residents’ health status.
However, no previous study has considered the comprehensive health risk due to overall residential environment. Therefore, a
large-scale nationwide questionnaire survey was conducted using CASBEE Health Checklist to examine the residential environment
of detached houses and residents’ health status. Results show that overall residential environment was likely an important
determinant of health and was associated with disease prevalence among residents.

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QUESTIONNAIRE-BASED VALIDATION OF ENVIRONMENTAL PERFORMANCE ASSESSMENT TOOL FOR MUNICIPALITIES

川久保俊, 伊香賀俊治, 村上周三

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 78 ( 693 ) 883-892 - 892 2013.11

Research paper (scientific journal), Joint Work, Accepted, ISSN 1348-0685

CASBEE-City, a comprehensive environmental assessment tool for municipalities (cities, towns, and villages), was developed to support citizens, local governments, and other stakeholders in understanding their local conditions. In this study, the aim was to examine the tool’s practical effectiveness through a nationwide questionnaire survey. The statistical relationship was analyzed between the subjective assessment results (citizens’ satisfaction with local conditions) and the objective CASBEE-City assessment results, which are based on public statistical information. A clear relationship was found between the subjective and objective assessment results for municipalities, thus verifying the tool’s effectiveness.

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DEVELOPMENT OF A ENVIRONMENTAL PERFORMANCE ASSESSMENT TOOL FOR MUNICIPALITIES INCORPORATING DATABASE AND GIS APPLICATION

Shun KAWAKUBO, Toshiharu IKAGA and Shuzo MURAKAMI

AIJ Journal of Technology and Design (Architectural Institute of Japan) 19 ( 43 ) 1023-1026 - 1026 2013.10

Research paper (scientific journal), Joint Work, Accepted, ISSN 1341-9463

Environmental performance assessment tool for municipalities
(CASBEE-City) has been developed and upgraded since 2008. The tool automatically queries the database and extracts the necessary data for conducting the nationwide municipality assessment. The tool also incorporates GIS functionality and enables tool users to understand the conditions, strengths, and weaknesses of their municipalities in comparison with other municipalities in Japan by visualizing the assessment results on easy-to-understand maps.

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VISUALIZATION OF DISASTER RECOVERY PROCESS BASED ON A TIME-SERIES ASSESSMENT OF URBAN ENVIRONMENT

Shun KAWAKUBO, Toshiharu IKAGA and Shuzo MURAKAMI

AIJ Journal of Technology and Design (Architectural Institute of Japan) 19 ( 43 ) 1011-1016 - 1016 2013.10

Research paper (scientific journal), Joint Work, Accepted, ISSN 1341-9463

A time-series assessment of urban environment was carried out by using “CASBEE-City” tool in Kobe city to visualize the disaster recovery process. As a result of the assessment, it was revealed that the score for quality of Kobe city calculated by the tool got drastically worse soon after the great Hanshin-Awaji earthquake in 1995. However, the score for quality of Kobe city has gradually recovered after the earthquake and has improved to the current position along with the progress of the reconstruction.

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Assessment of low-carbon policy implications in China’s urban residential sector

Rui XING and Toshiharu IKAGA

International Journal of Sustainable Building Technology and Urban Development (SUSB Journal) (Sustainable Building Research Center (Korea)) 4 ( 3 ) 229-242 - 242 2013.09

Research paper (scientific journal), Joint Work, Accepted, ISSN 2093-761X

In this paper, we present a micro-model designed to assess the effectiveness of low-carbon policies in addressing the energy problems faced by the Chinese urban residential sector. This micro-model first evaluates CO2 emissions based on available information for the residential sector, including the number of households, floor area and domestic appliance ownership. Two efficiency scenarios are then combined to form the simulation model: Chinese government policies and the low carbon plans of OECD (Organisation for Economic Co-operation and Development) countries. The simulation model estimates future emissions growth and the CO2 reduction potential of two efficiency scenarios. The results indicate that when government policies align with the efforts of residents, there is opportunity to reduce CO2 emissions in Chinese residential buildings for a relatively low price. In the frozen technology scenario, data shows that in all 31 province-level divisions, CO2 emission growth will see a 10-fold increase over the 2000 level. However, when compared with the frozen technology scenario, the reduction scenario shows reductions of 20% (warm areas) to 40% (cold areas). In the abatement scenario the reduction rates could be brought up to 50%. The model's outputs can be used to support decision-making when setting appropriate CO2 emission reduction goals. © 2013 Copyright Taylor and Francis Group, LLC.

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DEVELOPMENT OF A SUGGESTION TOOL FOR ENERGY-SAVING ACTIONS BASED ON THE ANALYSIS OF RESIDENTS’ BEHAVIORS AND ENERGY CONSUMPTION

Daisuke TOMIKOSHI, Toshiharu IKAGA, Shun KAWAKUBO and Kota FUJISAKI

AIJ Journal of Technology and Design (Architectural Institute of Japan) 19 ( 42 ) 655-660 - 660 2013.06

Research paper (scientific journal), Joint Work, Accepted, ISSN 1341-9463

It is important to promote energy-saving actions toward the reduction of CO2 emissions residential sector. Residents should understand the actual conditions of energy consumption in their home in order to make energy-saving actions more effective. Therefore, in this research, a tool
which suggests effective energy-saving actions was developed based on literature research and questionnaire survey. A workshop was conducted in Kawasaki City. Then, the residents received the information of their actual energy usage and effective energy-saving actions suggested by the aforementioned tool. As a result, 6.4% of CO2 reduction was
achieved.

LONG-TERM ESTIMATE OF CO2 BALANCE CONSIDERING FOREST-GROWTH CYCLE IN PROMOTING THE USE OF CONSTRUCTION TIMBER

Takuhei USHIRO, Toshiharu IKAGA and Kosuke MEGURO

AIJ Journal of Technology and Design (Architectural Institute of Japan) 19 ( 42 ) 649-654 - 654 2013.06

Research paper (scientific journal), Joint Work, Accepted, ISSN 1341-9463

In this study, we model the estimation of the CO2 balance throughout the life cycle of construction timber. We study about construction utilization period considering forest-growth and show the long-term estimate of the emission reduction effect. As a result, it was found that CO2 balance
become plus (absorption) using Japanese cedar and cypress in Kochi Prefecture more than 50 years as construction timber. Moreover, as a result of long-term estimate, we show emission reduction effect by increasing the construction timber volume and extending the utilization period.

SURVEY RESEARCH ON THE REGULATIONS FOR ENERGY EFFICIENCY OF RESIDENTIAL AND NON-RESIDENTIAL BUILDINGS IN THE FOREIGN COUNTRIES

Tadashi MIZUISHI, Toshiharu IKAGA, Shuzo MURAKAMI and Sin-ichi TANABE

AIJ Journal of Technology and Design (Architectural Institute of Japan) 19 ( 41 ) 225-230 - 230 2013.03

Research paper (scientific journal), Joint Work, Accepted, ISSN 13419463 18818188

Residential and commercial building sector accounts for more than 30% of final energy consumption in Japan and an increase from the past is remarkable. In order to realize a low-carbon society, further strengthening of energy saving measures is essential. Japanese government is considering a mandatory policy scheme which forces all residential and non-residential buildings to meet the energy efficiency standard by 2020. This research aims to marshal trends on regulations for energy efficiency of residential and non-residential buildings within countries which implements advanced measures, and to obtain referential knowledge for Japan’s energy efficiency measures.

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MODELING OF DIFFUSION PROCESS OF WELL INSULATED HOUSE THROUGH PRESENTING ENERGY BENEFITS AND NON-ENERGY BENEFITS

Kota FUJISAKI, Toshiharu IKAGA, Shun KAWAKUBO and Daisuke TOMIKOSHI

AIJ Journal of Technology and Design (Architectural Institute of Japan) 19 ( 41 ) 231-236 - 236 2013.03

Research paper (scientific journal), Joint Work, Accepted, ISSN 13419463 18818188

It is necessary to consider measures to promote well insulated houses toward the reduction of CO2 emissions in residential sector. However, it is difficult to determine effective measures since residents’ attitude toward introducing insulation differ from one by one. Therefore, in this study, a model for predicting the diffusion process of well insulated house was developed taking residents’ attitude toward introducing insulation into account. The model enables us to consider effective measures for promoting well insulated house. As a result of case study, presenting energy benefits and non-energy benefits was more effective than giving economic incentive in the study.

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DEVELOPMENT OF BUSINESS SCHEME FOR DECENTRALIZED ENERGY NETWORK PROJECTS BY REDISTRIBUTING NON-ENERGY BENEFITS Study on Low-carbon Communities and Cities by use of Decentralized Energy Network

水石仁, 伊香賀俊治, 村上周三, 工月良太, 山田航也

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 78 ( 684 ) 175-182 2013.02

Research paper (scientific journal), Joint Work, Accepted, ISSN 1348-0685

1. This study has carried out a cost benefits analysis for each stakeholder in an attempt to develop low-carbon communities and cities by implementing regional cogeneration systems and leasing photovoltaic systems to commercial buildings.
2. As a result, the economic benefits for energy service provider acting as an investor have been proved when non-energy benefits (NEBs) are accounted. In addition, numerous benefits to stakeholders other than investor have been proved. Also, subsidies by public sector (National, Local Government) or tax incentive program will increase the economic efficiency for energy service provider (investor).
3. Since building owners and building users will gain NEBs such as of increase in real estate value, risk reduction (contribution of business and living continuity plan (BLCP), regulatory compliance etc) and maintenance cost reduction, possibility for redistribution of NEBs to the energy service provider (investor) in the form of service charge (rent, energy expense etc) have also been considered.

ENVIRONMENTAL PERFORMANCE ASSESSMENT OF MUNICIPALITIES WITH THE “CASBEE-CITY” TOOL

Shun Kawakubo, Toshiharu Ikaga, Shuzo Murakami, Yasushi Asami

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 78 ( 683 ) 63-73 - 72 2013.01

Research paper (scientific journal), Joint Work, Accepted, ISSN 1348-0685

A comprehensive, nationwide assessment of whole municipalities in Japan was conducted using the Comprehensive Assessment System for Built Environment Efficiency (CASBEE) tool specifically designed for city level assessment (CASBEE-City). As with other tools in the CASBEE family, CASBEE-City is also based on the concept of environmental efficiency and calculates the value for built environment efficiency (BEE). In this study, BEE is calculated by using public statistical information and visually displayed on a map through a geographic information system (GIS) to understand the current situation of all municipalities in Japan under the same assessment criteria (same assessment items, thresholds and rating functions).

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A STUDY OF EFFECTIVE GLOBAL WARMING COUNTERMEASURES AND MARGINAL ABATEMENT COST FOR THE CHINESE PREFECTURAL RESIDENTIAL SECTOR

Rui Xing, Toshiharu Ikaga

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 77 ( 681 ) 899-907 - 907 2012.11

Research paper (scientific journal), Joint Work, Accepted, ISSN 1348-0685

In recent years, with improvements in living standards, energy consumption and CO2 emissions of Chinese residential sector have both increased considerably. However, we do not have a clear vision of future growth in energy consumption and lack tools for evaluating the impact of energy saving measures. This paper discusses the sustainability of Chinese residential buildings from the following 3 aspects:
1. Analyzing the future growth of energy consumption in Chinese residential buildings.
2. Evaluating the reduction potential of CO2 emissions through the implements of various energy saving measures.
3. Calculating the marginal abatement cost of proposed countermeasures and evaluating them from an economic perspective.　
As results, we found that efficiency policies could bring about 70% CO2 emissions reduction in maximum. Hence, most of the efficiency policies have positive effects on saving energy bills, thus the marginal abatement costs are able to be managed in a minus level.

DEVELOPMENT OF REGIONAL ENVIRONMENT ASSESSMENT TOOL FOR HEALTH PROMOTION AND VALIDATION OF THE EFFECTIVENESS

出口満, 伊香賀俊治, 村上周三, 白石靖幸, 星旦二, 加藤龍一, 川久保俊, 安藤真太朗

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 77 ( 681 ) 837-847 - 846 2012.11

Research paper (scientific journal), Joint Work, Accepted, ISSN 1348-0685

Population aging is accelerating in many developed countries and there are growing concerns about increasing social security costs. Given this background, as stated in the Japanese Growth Strategy, community that can sustain citizens' lifelong health and active living is required. Therefore, this study aims to develop a healthy community checklist based on citizens’ consciousness and behavior survey to recognize the condition of their community and notice the risk factor of disease. Based on the answer of the respondents, the score for a community was calculated and verified the effectiveness of this tool. As the result, the relationship between overall community score and citizens' health condition was quantified. Furthermore, the result showed a significant relationship between the community environment and the personal health, even in the case of considering personal life style.

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子どもの地域活動の参加要因と健康関連要因の構造分析 −保護者の意識・行動および地域の安全環境に着目して−

樋野公宏, 白石靖幸, 星旦二, 伊香賀俊治

日本建築学会計画系論文集 (Architectural Institute of Japan) 77 ( 679 ) 2119-2125 - 2125 2012.09

Research paper (scientific journal), Joint Work, Accepted, ISSN 1348-0685

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A FIELD SURVEY OF CLASSROOM ENVIRONMENTAL QUALITY IN TERMS OF STUDENTS’ PHYSICAL CONDITIONS AND CONCENTRATION

Yuki Yanai, Toshiharu Ikaga, Shun Kawakubo

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 77 ( 676 ) 533-539 - 539 2012.06

Research paper (scientific journal), Joint Work, Accepted, ISSN 1348-0685

In order to clarify the effect of classroom environmental quality on students’ health and learning performance, field measurements, assessments using CASBEE-School (Comprehensive Assessment System for Built Environment Efficiency for school) , and　questionnaire survey for students and their teachers were conducted in 12 elementary schools. From the results of the survey conducted in both summer and winter, a significant correlation was observed between score for Q1 (indoor environment) category of CASBEE-School and students’ satisfaction with their classroom in each school, and effectiveness of assessments by CASBEE-School was validated. However, there is still room for further improvement of assessment system in detail. In addition, a significant correlation between students’ satisfaction and both of physical conditions and concentration was observed in this study.

THE FORECASTING MODEL OF CO2 EMISSIONS UP TO 2050 FOR RESIDENTIAL SECTOR OF TAIWAN

Yushiuan CHENG, Toshiharu IKAGA, Yuki YANAI

AIJ Journal of Technology and Design (Architectural Institute of Japan) 18 ( 39 ) 633-638 - 638 2012.06

Research paper (scientific journal), Joint Work, Accepted, ISSN 1341-9463

In the past two decades, CO2 emissions in Taiwan have sharply increased, but models for forecasting the future trend are still insufficient. In this study, based on the energy consumption of residential sector from 1990 to 2010, CO2 emissions were estimated up to 2050 using the macro simulation method. The model presents the final energy consumption and CO2 emissions by category of fuels and final usages. Several scenarios were applied to examine the possibility of achieving the goal set by the government; the most effective result shows 27% reduction by 2020 and 64% reduction of CO2 emissions by 2050.

HIERARCHICAL STRUCTURE ANALYSIS OF ADULT RESIDENTS’ HEALTH BY DEVELOPING MULTIPLE INDICATORS MODEL

安藤真太朗，伊香賀俊治，白石靖幸，星　旦二，川村健一，川久保　俊，大重和恵

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 77 ( 675 ) 389-397 2012.05

Research paper (scientific journal), Joint Work, Accepted, ISSN 1348-0685

A questionnaire survey was administered to adult residents of three locales: a large city (Kitakyushu city); a small city (Obuse Town); and a rural village (Yusuhara town), in order to clarify the hierarchical structure of health related factors of housing and regional environment dependent on urban structure and scale. As a result of structural equation modeling, health related factors model in Yusuhara was shown that 35% of residents’ overall health may depend on their housing and regional environment, and it was the largest percentage of three locales. Besides, differences were found among the health related factors structure. These results indicate that design guidelines for health promotion that correspond to the urban structure and scale will be required.

DEVELOPING A LCA DATABASE OF WOOD MATERIALS

Yusuke Nambu, Toshiharu Ikaga, Hiroki Hondo, Kensuke Kobayashi, Yuko Tsunetsugu

AIJ Journal of Technology and Design (Architectural Institute of Japan) 18 ( 38 ) 269-274 - 274 2012.02

Research paper (scientific journal), Joint Work, Accepted, ISSN 1341-9463

At present, the use of eco-friendly building materials is needed in order to reduce the environmental load. From this viewpoint, a LCA database has been established by the Architectural Institute of Japan. However, the database has two problems. First, the environmental load of imported wood materials is not evaluated. Second, the environmental load of wood materials in the database is stored as an average value. The purpose of this study is developing a LCA database of wood materials that takes into account imported wood materials and contains detailed data for the forestry, manufacturing, and transport stages.

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DEVELOPMENT OF THE DATABASE FOR STOCK AND FLOW FLOOR AREA OF NON-RESIDENTIAL BUILDINGS CLASSIFIED BY BUILDING USE TYPE AND AREA

Kumi Okumura, Toshiharu Ikaga, Shun Kawakubo

AIJ Journal of Technology and Design (Architectural Institute of Japan) 18 ( 38 ) 275-278 - 280 2012.02

Research paper (scientific journal), Joint Work, Accepted, ISSN 1341-9463

Toward mitigation of climate change, the Japanese government targeted that greenhouse gas emissions will be reduced by 80% of the 1990 level by 2050. However, CO2 emissions in non-residential sector are rapidly increasing, making carbon reduction in this sector a crucial concern. It is essential to establish CO2 reduction target and agenda based on the analysis of energy consumption and the prediction of the CO2 reduction potential. However, a lack of statistical data of floor area makes it difficult to conduct an analysis and prediction. Therefore, database for floor area of non-residential buildings has been developed in this study. This database includes stock and flow data of floor area by building use type and area which have a major impact on energy consumption in nonresidential buildings. This database can provide valuable information for carrying out countermeasures in non-residential sector.

VALIDATION OF THE EFFECTIVENESS OF RESIDENTIAL ENVIRONMENT ASSESSMENT TOOL FOR HEALTH PROMOTION

Eri TAKAYANAGI, Toshiharu IKAGA, Shuzo MURAKAMI, Tsuyoshi SEIKE and Junta NAKANO

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 76 ( 670 ) 1101-1108 - 1108 2011.12

Research paper (scientific journal), Joint Work, Accepted, ISSN 1348-0685

The number of patients with heat stroke, sleep disorder and heat shock caused by poor indoor condition increased, becoming a major social issue. As the house is the base of life, the improvement of residential environment that supports resident's health is a pressing issue. This study figured out the effect of residential environment on resident’s health and developed the residential environment
assessment tool for health promotion. Then, verified the effectiveness of this tool. People recognize the level of their house and notice the risk factors of disease in their house through the evaluation result with this tool. It will be highly motivating for them to improve the residential environment for health promotion.

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Nationwide Assessment of City Performance Based on Environmental Efficiency

Shun KAWAKUBO, Toshiharu IKAGA and Shuzo MURAKAMI

International Journal of Sustainable Building Technology and Urban Development (SUSB Journal) (Sustainable Building Research Center (Korea)) 2 ( 4 ) 293-301 - 301 2011.12

Research paper (scientific journal), Joint Work, Accepted, ISSN 2093-761X

Cities must improve their quality without an increase, or ideally with a decrease, in the amount of environmental load to become more sustainable. In order to monitor city's progress towards sustainable development goals, a comprehensive Assessment System for Built Environment Efficiency (CASBEE) tool, named CASBEE-City has been developed. All cities in Japan are assessed from the following two aspects: environmental load (L) on the external environment and quality (Q), which represents
the citizens' quality of life inside the city. Built environment efficiency (BEE = Q/L) is then calculated for the comprehensive assessment of each city. A high BEE value indicates that the city has excellent environmental efficiency. The assessment results are visually displayed on the map by using a geographic information system so that citizens, local government officers, and all other stakeholders can easily understand the actual status of their city in comparison with other cities in the country. This assessment and the visualization of the results are expected to support the realization of future sustainable cities.

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Development of a prediction model of low-carbon technology adoption rate based on the detached homeowners' decision-making structure

Mitsuru Deguchi, Toshiharu Ikaga, Shun Kawakubo, Kumi Okumura

AIJ Journal of Technology and Design (Architectural Institute of Japan) 17 ( 37 ) 949-954 - 954 2011.10

Research paper (scientific journal), Joint Work, Accepted, ISSN 1341-9463

In 2009, the Japanese government published their greenhouse gas (GHG) emission reduction target to reduce GHGs by 25% by 2020 and 80% by 2050. To meet this target, formulating suitable policy has become an urgent issue. In this study, we have developed a model for predicting the low-carbon technology adoption rate based on the detached homeowners' decision-making structures. In addition, we have considered policies for meeting the reduction target. This study aims to propose policies to meet the reduction target, and to contribute to the realization of a low-carbon society.

Study on scenarios towards low carbon society in residential sector

Tomoko IWATA, Yasuo KUWASAWA, Shuzo MURAKAMI and Toshiharu IKAGA

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 76 ( 667 ) 839-846 - 846 2011.09

Research paper (scientific journal), Joint Work, Accepted, ISSN 1348-0685

The effect of CO 2 reduction in Japanese residential sector on various future scenarios for low-carbon society was estimated by the developed forecasting model considering the difference of energy consumption structure in different family types, different geographical area and different house types. Based on the results of forecasting model simulation by 2050, needed policies to achieve the Japanese CO 2 reduction goal (25% reduction at 2020 and 80% reduction at 2050 comparing to CO 2 emission at 1990) was discussed in this study. Results of forecasting simulation showed following 2 aspects. 1. Spread of low carbon technologies (LCT) into residential sector was indispensable to achieve the CO 2 reduction goal in 2050, however, the spread speed of LCT couldn't catch up with the expected speed of CO 2 reduction to reach the goal in 2020. As an additional measure, reduction of CO 2 emission factor for electricity was indispensable. 2. Spread of LCT into existing houses was indispensable to achieve CO 2 reduction goal both in 2020 and 2050, because the CO 2 reduction was not enough to achieve those goals even if the introduction of LCT was obligated to all of new buildings.

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EVALUATION OF INVESTMENT IN RESIDENTIAL THERMAL INSULATION CONSIDERING NON-ENERGY BENEFITS DELIVERED BY HEALTH

Toshiharu IKAGA, Rika EGUCHI, Shuzo MURAKAMI, Atsushi IWAMAE, Tanji HOSHI, Tadashi MIZUISHI, Shun KAWAKUBO and Kumi OKUMURA

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 76 ( 666 ) 735-740 - 740 2011.08

Research paper (scientific journal), Joint Work, Accepted, ISSN 1348-0685

It takes many years to recover the initial investment cost for installing housing insulation through savings from energy reduction (Energy Benefit: EB), since construction cost is very high in Japan. This long payback time is the major barrier to the promotion of well-insulated houses. However, it has been found that if Non-Energy Benefits (NEB) of well insulated houses, such as improvement in personal health, reduction of medical expenses and decline in absences from work are all taken into account, the time required to recover the initial investment cost would change from 29 to 16 years. Therefore recognition of NEB is expected to encourage residents to invest in residential thermal insulation. NEB of well-insulated houses is thus evaluated regarding human health in this study.

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Shintaro ANDO, Yasuyuki SHIRAISHI, Toshiharu IKAGA, and Tanji HOSHI

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 76 ( 664 ) 573-580 - 580 2011.06

Research paper (scientific journal), Joint Work, Accepted, ISSN 1348-0685

The purpose of this study is to analyze the health determinant factors of housing and regional environment in the suburb of Kitakyushu. A questionnaire survey was carried out among the middle-aged and elderly people in Yatsue district, the city of Kitakyushu, in order to clarify the respective influence of houses and regional environment, including the various sur-rounding environments, on residents' health. As for self-rated health, 80% of the respondents claimed, “I am in good health” or “I am not in bad health”, and there was no great distinction among age groups. The result can be shown that this district is healthy. Health related factors modeling showing the relations among housing, regional environments, and health was proposed, based on structural equation modeling. This model indicated that 23% of residents' health may be dependent on the influences of their houses and regional environments. This model also showed that residents' health had strong cor-relation to questionnaire items such as “indoor thermal environment” of houses, and “community activities”, “neighbor-ship” and “green space” for regional environments. Therefore, it is possible that residents' health may require appropriate maintenance through creation of good house and regional environment.

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A 2050 Forecast Research on Effective Global Warming Countermeasures of Residential Sector in China

Rui XING and Toshiharu IKAGA

Journal of Asian Architecture and Building Engineering (Architectural Institute of Japan) 10 ( 1 ) 221-225 2011.05

Research paper (scientific journal), Joint Work, Accepted

Energy consumption in the Chinese residential sector is increasing quickly. In this study, we developed a Micro-model to forecast residential CO2 emissions. The model outputs support decision making for appropriate CO2 emission reduction goals. First, for Chinese urban residential buildings, we developed a CO2 emissions forecast model for 2050 taking into account lifestyle changes and Global Warming countermeasures. Second, we used the model to estimate the CO2 reduction potential of both residential and electrical countermeasures. Compared to the business as usual (BaU) scenario, implementation of residential countermeasures achieved 38%, 24% and 23% emissions reductions for Beijing, Shanghai and Hong Kong respectively. After combining them with the implementation of electrical countermeasures the reduction rates rose to 60%. We also compared the countermeasures to see which could bring the greatest emissions reduction. For Beijing, improvement of insulation was most efficient. For Shanghai and Hong Kong, COP increase of hot water supply appears to be the most efficient countermeasure. Through this study we were able to model global warming countermeasures for the Chinese residential sector, and found that reducing CO2 emissions by 60% from BaU is an achievable goal.

Development of a comprehensive city assessment tool: CASBEE-City

Shuzo MURAKAMI, Shun KAWAKUBO, Yasushi ASAMI, Toshiharu IKAGA, Nobuhaya YAMAGUCHI and Shinichi KABURAGI

Building Research & Information (Routledge, Taylor & Francis Group (London)) 39 ( 3 ) 195-210 - 210 2011.04

Research paper (scientific journal), Joint Work, Accepted, ISSN 0961-3218

Conducting city assessments and disclosing those results to the public is important for supporting citizens’ understanding
of the actual condition of their city. Such assessment and disclosure could introduce a market mechanism that can be
expected to provide city governments with strong incentives to improve their city conditions and also recognizes that
local policy and strategy can be the most appropriate way to address specific urban and environmental problems.
The latest Comprehensive Assessment System for Built Environment Efficiency (CASBEE) tool, referred to as
CASBEE-City, is presented. Designed specifically for city assessment, it supports local governments and other
stakeholders in identifying the environmental, social and economic characteristics of their city and in quantifying the
effectiveness of their city-wide policies. CASBEE-City is based on the concept of environmental efficiency and it
provides a combined evaluation of a city embracing two aspects: the environmental load imposed by the city on the
wider environment outside its boundary, and the quality of life (environmental, social, economic) inside the city. A
city with low environmental load and high quality receives a high Built Environment Efficiency (BEE) value and is
regarded as a sustainable city within the CASBEE framework.

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都市の総合環境性能評価ツールCASBEE-都市の開発, 評価システムの理念と枠組み

村上　周三，川久保　俊，浅見　泰司，伊香賀　俊治，山口　信逸，蕪木　伸一

AIJ Journal of Technology and Design (Architectural Institute of Japan) ( 35 ) 239-242 2011.02

Research paper (scientific journal), Joint Work, Accepted

建築における木質バイオマスの有効利活用に関する研究、マテリアルフロー分析と未利用材の利活用可能性の検討

小林謙介, 中島史郎, 恒次祐子, 伊香賀俊治

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 76 ( 659 ) 91-96 2011.01

Research paper (scientific journal), Joint Work, Accepted, ISSN 1348-0685

Factor X (Eco-Efficiency) Assessment on Global Warming a Household in Japan

Taeko AOE, Ryoichi YAMAMOTO, Toshiharu IKAGA, Yasushi KONDO, Yuichi MATSUOKA and Moriki FUKUDA

Journal of the Japan Institute of Energy (Japan Institute of Energy) 89 ( 11 ) 1070-1087 - 1087 2010.11

Research paper (scientific journal), Joint Work, Accepted, ISSN 0916-8753

This paper proposes a new method for evaluating the eco-efficiency of a household based on Factor X, which was proposed by Yamamoto and colleagues in 1999. We had proposed methods for evaluating Factor X of a household which consists of a building and home appliances, and implemented empirical evaluations. However, there remained the following two issues to be considered. One is how to quantify the function of a household. The other is how to take account of the so-called synergy effects. It proposes the method for calculating the overall functions of one household using the purchasing price as a weighting coefficient. This method is the same as Laspeyres quantity index in economics fields. As a synergy effect, the insulating effect in the building, etc. are considered. The result showed that the annual greenhouse gas emission of a typical household drastically decreased by 52.2% from 1990 to 2009 while the aggregated function of the household slightly decreased by 0.2% during the same period so that Factor X was 2.1 with respect to global warming. It was thus shown quantitatively that Factor X of households in Japan presumably improved during the period although only limited assessments were implemented.

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Evaluation of marginal abatement cost of community-wide energy utilization, Study on non-energy benefits (NEB) by area-wide energy utilization (part 2)

Ryota KUZUKI, Toshiharu IKAGA, Shuzo MURAKAMI, Yoshio KATO, Tsutsumi TANAKA, Yuichi IKUTA

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 75 ( 656 ) 915-921 - 921 2010.10

Research paper (scientific journal), Joint Work, Accepted, ISSN 1348-0685

Toward low-carbon society, much higher use of renewable energy and unused energy should be promoted. For this purpose, area-wide energy utilization is expected to play an important role in commercial and residential sectors. Along with the compact city policy, area-wide energy utilization in rather wide scale such as in a community and in a city should be strategically planned and implemented. Among various carbon reduction measures, those of higher reduction potential and higher cost-benefit ratio should be prioritized. This paper describes an appropriate way of determining the priority by use of marginal abatement cost (MAC), taking the following viewpoints into consideration.; 1) Setting payback-periods based on functional lifetime of each reduction measure 2) Qualifying non-energy benefits (NEB) to be deducted from the MAC of each reduction measure A case study for a community-scale energy utilization by use of incineration waste heat is undertaken to validate the above concept.

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Practical Study on HVAC Control Technology Based on the Learning Function and Optimum Multiple Objective Processes

Haruka UEDA, Ryota DAZAI, Chosei KASEDA, Toshiharu IKAGA and Akihiro KATO

計測自動制御学会論文集 (The Society of Instrument and Control Engineers) 46 ( 8 ) 439-447 2010.08

Research paper (scientific journal), Joint Work, Accepted, ISSN 0916-8753

Demand among large office buildings for the energy-saving benefits of the HVAC (Heating,Ventilating and Air-Conditioning)System are increasing as more and more people become concerned with global environmental issues. However,immoderate measures taken in the interest of energy conservation may encroach on the thermal comfort and productivity level of office workers. Building management should satisfy both indoor thermal comfort and energy conservation while adapting to the many regulatory, social, climate, and other changes that occur during the lifespan of the building. This paper demonstrates how optimal control of the HVAC system, based on data modeling and the multi-objective optimal method,achieves an efficient equilibrium between thermal comfort and energy conservation.

Identification and allocation of stakeholders’ benefits, Study on non-energy benefits (NEB) by area-wide energy utilization

工月良太，伊香賀俊治，村上周三

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 75 ( 653 ) 645-652 2010.07

Research paper (scientific journal), Joint Work, Accepted, ISSN 1348-0685

上海の都市住宅におけるCO2排出量の2050年までの予測

シンレイ, 伊香賀俊治, 大城賢, 木本慶介

AIJ Journal of Technology and Design (Architectural Institute of Japan) 16 ( 34 ) 1016-1019 2010.06

Research paper (scientific journal), Joint Work, Accepted

These years residential energy consumption has been increasing sharply in China along with the high economic growth. Thus people pay much more attention to the issues of reducing the energy consumption and CO2 emission. This study chose Shanghai, a big city of China as a subject, and developed a Macro-model to forecast the CO2 emission of residential buildings up to 2050. By combining such Global warming count measures into the Macro-model it was able to forecast the CO2 emission of Shanghai’s residential buildings in several energy-efficient scenarios.

ESTIMATION OF CO2 REDUCTION POTENTIAL IN SMALL CITIES AND TOWNS CONSIDERING THE CHANGE OF SOCIAL SITUATION

Shun KAWAKUBO, Toshiharu IKAGA, Shuzo MURAKAMI

AIJ Journal of Technology and Design (Architectural Institute of Japan) 16 ( 33 ) 595-600 - 600 2010.06

Research paper (scientific journal), Joint Work, Accepted, ISSN 1341-9463

Enhancement of the governance and the cooperative structure of local governments toward the reduction of carbon output is becoming more and more important. In this study, the CO2 reduction potential of the town of Yusuhara - selected as one of the “Eco-model Cities for the Low Carbon Society” (EMC) by the Japanese cabinet office - is estimated considering the change of social situation. Such estimation supports local governments to formulate their action plans and contributes to the realization of low carbon society.

SURVEY RESEARCH ON FOREIGN URBAN ASSESSMENT TOOL AIMED AT REALIZATION OF SUSTAINABLE CITIES

Shun KAWAKUBO, Toshiharu IKAGA, Shuzo MURAKAMI

AIJ Journal of Technology and Design (Architectural Institute of Japan) 16 ( 33 ) 601-604 - 604 2010.06

Research paper (scientific journal), Joint Work, Accepted, ISSN 1341-9463

Indicators are partial reflections of reality. Those are necessary information we use to understand present conditions in cities, make our decisions, and plan future actions. Since environmental problems such as global warming and biodiversity loss are getting worse, the importance of urban/city assessment indicators as a mirror of current situation is increasing. Urban/City assessment indicators and tools are surveyed in this research, so that it can contribute to the realization of sustainable cities.

輸入木材のＬＣＡデータベースの構築

大城賢, 伊香賀俊治, 本藤祐樹

AIJ Journal of Technology and Design (Architectural Institute of Japan) 16 ( 33 ) 609-614 2010.06

Research paper (scientific journal), Joint Work, Accepted

THE TOTAL EFFECT ON PERFORMANCE AND ENERGY CONSUMPTION CAUSED BY OFFICE'S THERMAL ENVIRONMENT

Tomomi TAWADA, Toshiharu IKAGA, Shuzo MURAKAMI, Shoko UCHIDA, Haruka UEDA

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 75 ( 648 ) 213-219 - 219 2010.02

Research paper (scientific journal), Joint Work, Accepted, ISSN 1348-0685

Various researches highlight that indoor air quality affects performance of workers in offices. Although good indoor air quality improves work performance, it also increases energy consumption. In this study, we achieved a field survey in a real office in order to investigate the relationship between thermal environment, productivity, and energy consumption. In addition to the monitoring of indoor environmental quality and energy consumption, subjective experiments were conducted. In order to evaluate subjective performance, workers and students responded to questionnaires, and to evaluate objective performance, students simulated three types of office works. By calculating room temperature and worker's subjective performance, we demonstrate the correlation between room temperature and worker's performance (R2=0.22, p<0.01). Results show that the room temperature that maximizes worker's performance was 25.7°C.

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民生業務部門エネルギー消費原単位に関する各種資料の比較評価

平野勇二郎, 外岡豊, 伊香賀俊治, 亀卦川幸浩, 藤沼康実, 下田吉之

Journal of Environonmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 73 ( 633 ) 1331-1338 - 1339 2008.11

Research paper (scientific journal), Joint Work, Accepted, ISSN 1348-0685

This paper describes the results of a literature survey and comparative analysis of unit energy consumption data in the commercial sector. First, we collected 59 documents, including survey reports by administrative agencies, research papers by individual researchers, estimates based on existing surveys, and energy supply statistics. Then, we compared the data and clarified the consistency and variation. To determine the factors causing the variation, we used a dataset on completed buildings, compiled by the Japan Building Mechanical and Electrical Engineers Association.

室内空気汚染による健康被害のライフサイクル影響評価手法の開発、－室内空気汚染による健康被害に関する研究(その3)－

成田菜採, 村上周三, 伊香賀俊治, 坂部貢, 伊坪徳宏, 水石仁

Journal of Environonmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 73 ( 627 ) 695-700 2008.05

Research paper (scientific journal), Joint Work, Accepted

住宅および事務所ビルにおける温暖化対策の2050年までの予測

IKAGA Toshiharu

地球環境 (Association of International Research Initiatives for Environmental Studies) 12 ( 2 ) 191-199 2007.12

Research paper (scientific journal), Single Work, Accepted

CASBEE-まちづくりツールの概要、建築物総合環境性能評価システムの開発(その5)

村上周三，山口信逸，浅見泰司，伊香賀俊治，蕪木伸一，松隈　章，内池智広，橋本　崇

AIJ Journal of Technology and Design (Architectural Institute of Japan) ( 25 ) 191-196 2007.06

Research paper (scientific journal), Joint Work, Accepted, ISSN 1341-9463

吹付けウレタン断熱材の熱伝導率の長期経年変化に関する実験

MIZUTA Kazuhiko, MURAKAMI Shuzo, IKAGA Toshiharu and SEGUCHI

AIJ Journal of Technology and Design (Architectural Institute of Japan) 13 ( 25 ) 185-190 - 190 2007.06

Research paper (scientific journal), Joint Work, Accepted, ISSN 1341-9463

ウレタン壁内注入と窓の断熱改修効果の2020年までの予測、―住宅の断熱改修による温室効果ガス排出削減に関する研究―

IKAGA Toshiharu

Journal of Environonmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 72 ( 614 ) 99-106 - 106 2007.04

Research paper (scientific journal), Joint Work, Accepted, ISSN 1348-0685

This research describes effect of injecting rigid poly-urethane foam into walls and doubling glazing/sash as simple renovation methods for houses, according to the estimation of CO_2 emission by heating/cooling and LCCO_2 (Life Cycle CO_2). We estimated the CO_2 emission and LCCO_2 up to 2020 in Japan and obtained the following results. (l)Injecting rigid poly-urethane foam into walls where thermal insulation is little set up reduces LCCO_2 most for detached houses. (2)Renovation of openings brings more LCCO_2 reduction to houses insulated with 1993 energy saving standard in Tokyo. (3)When we choose one out of two methods above, we should take allowance for initial insulation level, house structure, and region. (4)Domestic CO_2 emission concerning thermal insulation for houses can be reduced by 13% to 19% in 2020 with the simple renovation methods.

住宅壁体モデル内へのウレタン注入による断熱改修実験とLCCO2評価

MIZUTA Kazuhiko, MURAKAMI Shuzo, IKAGA Toshiharu, KUROKI Shoichi, HAGIWARA Shinji and YOSHITOMI Kosuke

AIJ Journal of Technology and Design (Architectural Institute of Japan) 12 ( 24 ) 261-266 - 266 2006.12

Research paper (scientific journal), Joint Work, Accepted, ISSN 1341-9463

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現地調査に基づく地場産構造用集成材の環境影響評価

TSUDA Kohei, MURAKAMI Shuzo, IKAGA Toshiharu, KUMA Kengo, HONDO Hiroki and NARITA Natsumi

AIJ Journal of Technology and Design (Architectural Institute of Japan) 12 ( 24 ) 249-254 - 253 2006.12

Research paper (scientific journal), Joint Work, Accepted, ISSN 1341-9463

資源循環性評価のケーススタディ、建物の資源循環性評価手法の開発その２

SATO Masaaki, ARAI Yoshinobu, IKAGA Toshiharu, CHIKADA Toshiya, MAMIYA Hisashi and KATO Hiroshi

AIJ Journal of Technology and Design (Architectural Institute of Japan) 12 ( 24 ) 255-260 - 260 2006.12

Research paper (scientific journal), Joint Work, Accepted, ISSN 1341-9463

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集合住宅のライフサイクルにおける資源有効利用・建設廃棄物削減に関する研究

佐藤正章, 荒井良延, 伊香賀俊治, 近田智也, 間宮尚, 加藤正宏

Journal of Environonmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 71 ( 606 ) 67-74 - 73 2006.08

Research paper (scientific journal), Joint Work, Accepted, ISSN 1348-0685

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建築物総合環境性能評価システムの開発（その4） CASBEE-改修ツールの概要

佐藤正章, 村上周三, 高井啓明, 伊香賀俊治, 半澤久, 柳井崇, 遠藤純子, 吉澤伸記

AIJ Journal of Technology and Design (Architectural Institute of Japan) 12 ( 23 ) 259-264 - 264 2006.06

Research paper (scientific journal), Joint Work, Accepted, ISSN 1341-9463

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建築物総合環境性能評価システムの開発（その3）自治体版CASBEEの概要

遠藤純子, 村上周三, 伊香賀俊治, 吉澤伸記, 佐藤正章

AIJ Journal of Technology and Design (Architectural Institute of Japan) 12 ( 23 ) 237-240 - 240 2006.06

Research paper (scientific journal), Joint Work, Accepted, ISSN 1341-9463

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東京都都有施設における環境配慮型建築の環境・コスト評価システムの開発

林立也, 藤原孝行, 伊辺岳, 時田繁, 伊香賀俊治, 遠藤純子

AIJ Journal of Technology and Design (Architectural Institute of Japan) 12 ( 23 ) 253-258 - 258 2006.06

Research paper (scientific journal), Joint Work, Accepted, ISSN 1341-9463

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A Study on the CO2 Emission Reduction Effects of a Porous Residential Building Model in Hot and Humid Regions Part 2 -Reducing the Cooling Load by Component-scale Voids and the CO2 Emission Reduction Effect of the Model

Hirano T., Kato S., Murakami S., Ikaga T. and Shiraishi Y.

Building & Environment (Elsevier) 41 ( 1 ) 33-44 2006.01

Research paper (scientific journal), Joint Work, Accepted

A Study on the CO2 Emission Reduction Effects of a Porous Residential Building Model in Hot and Humid Regions Part 1 -Natural Ventilation Performance and Cooling Load Reduction Effect

Hirano T., Kato S., Murakami S., Ikaga T. and Shiraishi Y.

Building & Environment (Elsevier) 41 ( 1 ) 21-32 2006.01

Research paper (scientific journal), Joint Work, Accepted

資源循環性の評価機能を持つLCAツールの概要建物の資源循環性評価手法の開発その１

佐藤正章, 荒井良延, 伊香賀俊治, 近田智也, 間宮尚, 加藤正宏

AIJ Journal of Technology and Design (Architectural Institute of Japan) 22 ( 22 ) 341-346 - 346 2005.12

Research paper (scientific journal), Joint Work, Accepted, ISSN 1341-9463

住宅のエネルギー消費量とCO2排出量の都道府県別マクロシミュレーション手法の開発

IKAGA Toshiharu

AIJ Journal of Technology and Design (Architectural Institute of Japan) 22 ( 22 ) 263-268 - 268 2005.12

Research paper (scientific journal), Joint Work, Accepted, ISSN 1341-9463

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換気回数の変化が人間健康被害と内部・外部費用に与える影響のライフサイクルインパクト評価、－室内空気汚染による健康被害に関する研究(その2)－

成田菜採, 村上周三, 伊香賀俊治, 坂部貢, 伊坪徳宏, 水石仁

Journal of Environonmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 70 ( 595 ) 129-134 - 134 2005.09

Research paper (scientific journal), Joint Work, Accepted, ISSN 1348-0685

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室内空気汚染のライフサイクルインパクト評価手法の開発－室内空気汚染による健康被害に関する研究－

成田菜採, 村上周三, 伊香賀俊治, 坂部貢, 伊坪徳宏, 水石仁

Journal of Environonmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 70 ( 592 ) 83-88 - 88 2005.06

Research paper (scientific journal), Joint Work, Accepted, ISSN 1348-0685

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建築物総合環境性能評価システムの開発（その2） CASBEE-既存ツールの概要

IKAGA Toshiharu

AIJ Journal of Technology and Design (Architectural Institute of Japan) 13 ( 21 ) 211-216 - 430 2005.06

Research paper (scientific journal), Joint Work, Accepted, ISSN 1341-9463

A collaborative platform for sustainable building design based on model integration over the Internet

Kraines, Steven, Koyama M., Weber C., Ikaga T., Chikamoto T., Wallace D., Komiyama H.

International Journal of Environmental Technology and Management (Inderscience Enterprises Ltd.) 5 ( 2/3 ) 135-161 - 161 2005.06

Research paper (scientific journal), Joint Work, Accepted, ISSN 1466-2132

Considerable potential exists for reducing life cycle environmental impacts of buildings in Japan. While energy consumption during the operation stage of a building's lifetime is usually dominant, indirect energy use and pollutant emissions associated with production and disposal of building materials during construction and demolition are significant. For sustainable building design, interactions between the performance and dynamics of the building structure and energy systems must be considered. A collaborative platform based on the distributed object-based modeling environment, DOME, and a set of component models for sustainable building design analysis is presented. Integration examples of the component models to study particular building designs are described. Copyright © 2005 Inderscience Enterprises Ltd.

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戸建住宅の温暖化対策推進のためのCO2とコストの同時評価システムの開発

近本智行, 伊香賀俊治, 永瀬修

AIJ Journal of Technology and Design (Architectural Institute of Japan) 20 ( 20 ) 211-216 - 216 2004.12

Research paper (scientific journal), Joint Work, Accepted, ISSN 1341-9463

建築物総合環境性能評価システムの基本概念とツール群

村上周三, 岩村和夫, 坊垣和明, 坂本雄三, 野城智也, 伊香賀俊治, 遠藤純子

AIJ Journal of Technology and Design (Architectural Institute of Japan) ( 20 ) 199-204 2004.12

Research paper (scientific journal), Joint Work, Accepted

青森県県有施設における環境負荷低減手法の定量効果算定ツールの開発

林立也, 成田, 工藤, 駒井, 時田繁, 伊香賀俊治, 遠藤純子

AIJ Journal of Technology and Design (Architectural Institute of Japan) 10 ( 20 ) 205-210 - 210 2004.12

Research paper (scientific journal), Joint Work, Accepted, ISSN 1341-9463

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フロン漏洩を考慮した住宅断熱のLCCO2評価、－住宅の断熱強化による温室効果ガス削減に関する研究－

水石仁, 村上周三, 伊香賀俊治, フロン漏洩を考慮した住宅断熱のLCC, 評価

Journal of Environonmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 69 ( 579 ) 89-96 - 96 2004.05

Research paper (scientific journal), Joint Work, Accepted, ISSN 1348-0685

戸建と集合住宅のモデルを設定して、全国6気候地域区分毎に、年間暖冷房負荷シミュレーションを行い、日本の全住宅の暖冷房CO2排出量を2010年まで計算した。さらに、発泡断熱材に使用されているフロンガスの漏洩による温暖化影響と断熱強化によるCO2削減とのトレードオフ関係などを明らかにした。また、新築だけではなく既存住宅の対策の必要性を明らかにした。

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ポーラス型住棟における冷房負荷及びCO2排出量削減効果の検討－高温多湿気候下における環境負荷低減型住居に関する研究（その2）－

平野智子, 加藤信介, 村上周三, 伊香賀俊治, 白石靖幸, 上原瞳

Journal of Architectural Planning and Environonmental Engineering (Architectural Institute of Japan) 566 ( 566 ) 87-93 - 93 2003.04

Research paper (scientific journal), Joint Work, Accepted, ISSN 1348-0685

Forecast of CO2 Emissions fromConstruction and Operation of Buildings in Japan up to 2050

Toshiharu Ikaga, Shuzo Murakami, Shinsuke Kato and Yasuyuki Shiraishi

Journal of Asian Architecture and Building Engineering (Architectural Institute of Japan) 1 ( 2 ) 149-156 - 156 2002.11

Research paper (scientific journal), Joint Work, Accepted, ISSN 1347-2852

It is estimated that a third of carbon dioxide (CO2) emissions in Japan are created from construction and operation of buildings, and the construction industry is largely greatly responsible for this. Based on future population projections, a building floor area equivalent to that of Europe, the floor area of buildings already started, and an input and output analysis, a forecast of buildings-related CO2 emissions has been made up to 2050. If the current situation continues, CO2 emissions for the period 2008–2012 will rise by 15% compared to 1990 levels. On the other hand, if energy conservation measures are taken along with steps to prolong the life of buildings, reducing CO2 emissions by 30% in new construction work and by 15% in renovation work, and if the unit CO2 emission from electricity is reduced by 20% compared to 1990, CO2 emissions could be reduced by 6% over the period 2008–2012 and by 40% by 2050. We also examined the problems faced by the construction industry, making estimates classified by steps taken by the construction industry, steps taken by the power industry, and the year in which counter-measures are launched. © 2002, Architectural Institute of Japan. All rights reserved.

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ポーラス型住棟の自然換気量増加と冷房負荷削減効果の検討

白石靖幸, 村上周三, 加藤信介, 伊香賀俊治, 平野智子

Journal of Architectural Planning and Environonmental Engineering (Architectural Institute of Japan) 67 ( 558 ) 15-22 - 22 2002.08

Research paper (scientific journal), Joint Work, Accepted, ISSN 1340-4210

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ESTIMATION OF CO2 EMISSION ASSOCIATED WITH BUILDING CONSTRUCTION AND OPERATION TILL 2050 IN JAPAN ―Study on Social Life Cycle Assessment of Buildings and Cities―

IKAGA Toshiharu

Journal of Architectural Planning and Environonmental Engineering (Architectural Institute of Japan) 535 ( 535 ) 53-58 - 58 2000.09

Research paper (scientific journal), Joint Work, Accepted

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LCI Data on Electrical and Mechanical Facilities for Various Kinds of Buildings

IKAGA Toshiharu

Journal of Architectural Planning and Environonmental Engineering (Architectural Institute of Japan) 65 ( 533 ) 51-58 - 58 2000.07

Research paper (scientific journal), Joint Work, Accepted, ISSN 1340-4210

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LCI Data on Electrical and Mechanical Facilities of Office Buildings

IKAGA Toshiharu

Journal of Architectural Planning and Environonmental Engineering (Architectural Institute of Japan) 65 ( 529 ) 117-123 - 123 2000.03

Research paper (scientific journal), Joint Work, Accepted, ISSN 1340-4210

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2011年日本建築学会賞（作品）委員の見解

IKAGA Toshiharu

Journal of Architecture and Building Science (Architectural Institute of Japan) 126 ( 1621 ) 58-59 2011.08

Research paper (scientific journal), Single Work, ISSN 0003-8555

特集 Re-edit 環境学カタログ第二部　8.Technology（4）空調システムデザインから総合建築環境システムデザインの時代へ

IKAGA Toshiharu

Journal of Architecture and Building Science (Architectural Institute of Japan) 126 ( 1620 ) 23 2011.07

Research paper (scientific journal), Single Work, ISSN 0003-8555

特集建築年報2007 Ⅲ｜デザインレビュー　3｜環境建築環境性能表示の側面から

IKAGA Toshiharu

Journal of Architecture and Building Science (Architectural Institute of Japan) 122 ( 1566 ) 22 2007.09

Research paper (scientific journal), Single Work, ISSN 0003-8555

日本建築学会120年略史、地球環境問題への対応

IKAGA Toshiharu

Journal of Architecture and Building Science (Architectural Institute of Japan) 122 ( 1556 ) 94-95 2007.01

Research paper (scientific journal), Single Work

宇宙航空研究開発機構総合開発推進棟

IKAGA Toshiharu

Journal of Architecture and Building Science (Architectural Institute of Japan) 120 ( 1530 ) 60-61 2005.03

Research paper (scientific journal), Single Work, ISSN 1342-0739

設備・環境エンジニアリング、一歩先を行く研究への参画が設備・環境エンジニアの糧となる

IKAGA Toshiharu

Journal of Architecture and Building Science (Architectural Institute of Japan) 119 ( 1524 ) 40-41 2004.10

Research paper (scientific journal), Single Work, ISSN 0003-8555

Knowledge from Comprehensive Environmental Performance Labeling for Buildings

IKAGA Toshiharu

Journal of Architecture and Building Science (Architectural Institute of Japan) 118 ( 1505 ) 48-55 2003.05

Research paper (scientific journal), Single Work, ISSN 0003-8555

重要論文のレビューとリスト「環境負荷評価」

IKAGA Toshiharu

Journal of Architecture and Building Science (Architectural Institute of Japan) ( 1 ) 124-127 2003.02

Research paper (conference, symposium, etc.), Single Work, ISSN 1347-6548

日本建築学会における地球環境問題への取り組み

IKAGA Toshiharu

Journal of Architecture and Building Science (Architectural Institute of Japan) 117 ( 1487 ) 52-55 2002.02

Research paper (scientific journal), Single Work, ISSN 0003-8555

山梨県環境科学研究所

IKAGA Toshiharu

Journal of Architecture and Building Science (Architectural Institute of Japan) 116 ( 1468 ) 74-75 2001.03

Research paper (scientific journal), Joint Work, ISSN 1342-0739

「環境」で格付けされる21世紀

IKAGA Toshiharu

Journal of Architecture and Building Science (Architectural Institute of Japan) 116 ( 1465 ) 64 2001.01

Research paper (scientific journal), Single Work, ISSN 0003-8555

国際協力事業団北海道国際センター(帯広)

IKAGA Toshiharu

Journal of Architecture and Building Science (Architectural Institute of Japan) 114 ( 1435 ) 32-33 1991.03

Research paper (scientific journal), Joint Work, ISSN 0003-8555

Methodology and Case Study of Comprehensive Assessment System for Building Environmental Efficiency

IKAGA Toshiharu

空気調和・衛生工学 (The Society of Heating, Air-Conditioning and Sanitary Engineers of Japan) 78 ( 11 ) 17-24 2004.11

Research paper (scientific journal), Single Work, ISSN 0386-4081

[第39回学会賞技術賞受賞物件建築設備部門] 明治大学リバティタワーの空気調和・衛生設備

IKAGA Toshiharu

空気調和・衛生工学 (The Society of Heating, Air-Conditioning and Sanitary Engineers of Japan) 75 ( 11 ) 33-42 2001.11

Research paper (scientific journal), Joint Work, ISSN 0386-4081

[第15回振興賞技術振興賞受賞物件／東北支部] 岩手県立大学における環境親和型空調・衛生設備

IKAGA Toshiharu

空気調和・衛生工学 (The Society of Heating, Air-Conditioning and Sanitary Engineers of Japan) 75 ( 11 ) 68-72 2001.11

Research paper (scientific journal), Joint Work, ISSN 0386-4081

[第38回学会賞技術賞受賞物件建築設備部門] 山梨県環境科学研究所の環境共生型空調設備

IKAGA Toshiharu

空気調和・衛生工学 (The Society of Heating, Air-Conditioning and Sanitary Engineers of Japan) 74 ( 11 ) 47-55 2000.11

Research paper (scientific journal), Joint Work, ISSN 0386-4081

建築設備が地球環境に関わる問題の枠組み

IKAGA Toshiharu

空気調和・衛生工学 (The Society of Heating, Air-Conditioning and Sanitary Engineers of Japan) 70 ( 2 ) 3-11 1996.02

Research paper (scientific journal), Joint Work

[第8回振興賞技術振興賞受賞物件／北信越支部] 飯綱山荘の自然エネルギー複合利用環境・設備

IKAGA Toshiharu

空気調和・衛生工学 (The Society of Heating, Air-Conditioning and Sanitary Engineers of Japan) 68 ( 12 ) 94-97 1994.12

Research paper (scientific journal), Joint Work, ISSN 0386-4081

[講座]　大気環境の問題と対策(4)　CO2削減対策

IKAGA Toshiharu

空気調和・衛生工学 (The Society of Heating, Air-Conditioning and Sanitary Engineers of Japan) 68 ( 9 ) 43-49 1994.09

Research paper (scientific journal), Joint Work

[第28回学会賞技術賞受賞物件建築設備部門] 東京ドームの空気調和・衛生設備と空気膜構造維持設備

IKAGA Toshiharu

空気調和・衛生工学 (The Society of Heating, Air-Conditioning and Sanitary Engineers of Japan) 64 ( 12 ) 23-35 1990.12

Research paper (scientific journal), Joint Work, ISSN 0386-4081

[技術報告] 東京ドームの設備計画と実施 (その3)衛生設備・防災関連設備

IKAGA Toshiharu

空気調和・衛生工学 (The Society of Heating, Air-Conditioning and Sanitary Engineers of Japan) 64 ( 5 ) 59-68 1990.05

Research paper (scientific journal), Joint Work, ISSN 0386-4081

[技術報告] 東京ドームの設備計画と実施 (その2)空調設備

IKAGA Toshiharu

空気調和・衛生工学 (The Society of Heating, Air-Conditioning and Sanitary Engineers of Japan) 64 ( 4 ) 59-70 1990.04

Research paper (scientific journal), Joint Work, ISSN 0386-4081

[第27回学会賞技術賞受賞物件建築設備部門] 伊藤忠横浜港北ビルの空気調和設備

IKAGA Toshiharu

空気調和・衛生工学 (The Society of Heating, Air-Conditioning and Sanitary Engineers of Japan) 63 ( 12 ) 19-30 1989.12

Research paper (scientific journal), Joint Work, ISSN 0386-4081

建築物のライフサイクルとサステイナブルデザイン

IKAGA Toshiharu

生産研究 (東京大学生産技術研究所) 50 ( 12 ) 27-32 1998.12

Research paper (bulletin of university, research institution), Single Work

LCCM住宅評価ツールの開発

IKAGA Toshiharu

建築環境・省エネルギー情報IBEC (財団法人建築環境・省エネルギー機構) 32-6 ( 189 ) 39-44 2012.03

Research paper (scientific journal), Single Work, ISSN 0389-2638

健康の経済価値評価

IKAGA Toshiharu

コミュニケーション・レポート (財団法人住宅産業研修財団) ( 189 ) 10-19 2012.02

Research paper (other academic), Single Work

知的生産性研究最前線　経済性と評価／格付部会

IKAGA Toshiharu

建築環境・省エネルギー情報IBEC (財団法人建築環境・省エネルギー機構) 32-2 ( 185 ) 31-34 2011.07

Research paper (bulletin of university, research institution), Single Work, ISSN 0389-2638

低炭素化と健康維持増進を両立する住まいづくり

IKAGA Toshiharu

住宅金融 (独立行政法人住宅金融支援機構) ( 16 ) 61-69 2011.02

Research paper (bulletin of university, research institution), Single Work

特集：住まいと健康、快適な暮らしは、健康的な住まいから

Toshiharu IKAGA

きづき (ＯＭソーラー（株）) 23 8-16 2014.01

Research paper (scientific journal), Single Work

対談：家づくりは家族の健康のために

Toshiharu IKAGA and Akihisa IIDA

チルチンびと (株式会社風土社) ( 44 ) 46-51 2013.12

Research paper (scientific journal), Joint Work, ISSN 06150-01

Item response theory in building environment engineering: a novel approach to identifying key residential environment items

Shun Kawakubo, Tomomitsu Kamata, Shiro Arata, Shuzo Murakami, Toshiharu Ikaga, Yoshihisa Fujino, Junta Nakano, Shintaro Ando

Building and Environment (Elsevier BV) 262 111764 - 111764 2024.06

Research paper (scientific journal), Joint Work, Accepted, ISSN 0360-1323

The residential environment significantly influences residents’ health, quality of life, and well-being. Therefore, it is essential to assess the residential environment and implement improvement measures when problems are identified. In this context, the use of assessment tools such as BREEAM, LEED, and CASBEE has increased rapidly in recent years. Identifying key items with these assessment tools is crucial for prioritizing improvements to residential environment. This study introduces the novel application of item response theory (IRT) to building environment engineering data in order to identify key items from the CASBEE Residential Health Checklist. The strength of IRT lies in its ability to consider variations in scores for each item and the relative relationships between items, thereby enabling the identification of significantly influential key items. Examining Japanese residences, IRT identified 6 environmental items and 7 spatial items from a total of 44 items in the CASBEE Residential Health Checklist. Additionally, these environmental and spatial components were ranked by their explanatory power for the overall assessment of the residential environment. These findings contribute to prioritizing improvements in residential environments and provide a brief assessment method. IRT can be applied to other regions and building types, potentially enabling the identification of key items unique to each case. Thus, IRT is a versatile method with broad applicability for identifying key items in residential environment assessments.

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SEASONAL PATTERNS OF PHYSICAL ACTIVITY AND SEDENTARY BEHAVIOR AND INDOOR THERMAL ENVIRONMENT AMONG ADULTS LIVING IN SUBURBAN RESIDENTIAL AREA

Ito M., Ando S., Umishio W., Oguma Y., Saito Y., Ikaga T.

Journal of Environmental Engineering (Japan) (Journal of Environmental Engineering (Japan)) 89 ( 820 ) 340 - 350 2024.06

Research paper (scientific journal), Joint Work, Accepted, ISSN 13480685

This study examined the seasonal patterns of physical activity (PA) and sedentary behavior (SB) and the relationship between PA and SB and the indoor thermal environment in each season. 98 of 131 the participants were analyzed. 1) Daily moderate-to-vigorous PA was significantly greater in fall than in winter. 2) Adjusting the accelerometer wearing time, outdoor PA and SB were not significantly related to season, but indoor moderate-to-vigorous PA were significantly greater in fall and summer than in winter. 3) Using a kotatsu in winter was associated with longer SB and less light-intensity PA than using an air conditioner.

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Spatial and temporal indoor temperature differences at home and perceived coldness in winter: A cross-sectional analysis of the nationwide Smart Wellness Housing survey in Japan.

Wataru Umishio, Toshiharu Ikaga, Yoshihisa Fujino, Shintaro Ando, Tatsuhiko Kubo, Yukie Nakajima, Naoki Kagi, Tanji Hoshi, Masaru Suzuki, Kazuomi Kario, Takesumi Yoshimura, Hiroshi Yoshino, Shuzo Murakami

Environment international (Environment International) 186 108630 - 108630 2024.04

Research paper (scientific journal), Joint Work, Accepted, ISSN 01604120

Residents themselves are responsible for controlling their living environment, and their perception of coldness is important to protect their health. Although previous studies examined the association between perceived coldness and indoor temperature, they did not consider the spatial-temporal differences in indoor temperatures. This study, conducted in Japan, measured indoor temperatures in 1,553 houses across several rooms (living room, changing room, and bedroom) and heights (at 1 m above the floor and near the floor) over two weeks and obtained the perceived coldness from 2,793 participants during winter. Results showed substantial temperature differences between rooms (horizontal differences): 3.8 °C between living and changing rooms, and 4.1 °C between living rooms and bedrooms. The average vertical and diel (evening-morning) temperature differences in the living room were 3.1 °C and 3.0 °C, respectively. Regional analysis revealed that the Tohoku region experienced larger horizontal and diel indoor temperature differences, primarily due to its practice of intermittent and partial heating in living rooms only, in contrast to Hokkaido's approach of heating the entire house continuously. Despite Hokkaido's comprehensive heating system, it exhibited the largest vertical temperature difference of 5.1 °C in living rooms, highlighting the insufficiency of heating alone and the necessity for enhanced thermal insulation. The multivariate logistic regression analyses showed that average temperatures and vertical temperature differences were associated with perceived coldness, while horizontal and diel differences did not show a significant association, further emphasizing the importance of improved thermal insulation. Moreover, factors like individual attributes (age and gender), and lifestyle choices (meal quantity, exercise habits, alcohol consumption, and clothing amount) were significantly associated with coldness perception. Notably, older adults were less likely to perceive coldness but more vulnerable to the health impacts of low temperatures, underscoring the necessity of not solely relying on human perception for indoor temperature management to protect cold-related health problems.

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EFFECT OF MOVING TO HOUSES WITH THERMAL INSULATION PERFORMANCE ON HEALTH FOR CHILD-REARING AGE WOMEN

Ishii A., Ikaga T., Fukushima F., Tomioka Y., Mine T., Ohashi M.

Journal of Environmental Engineering (Japan) (Journal of Environmental Engineering (Japan)) 89 ( 817 ) 123 - 134 2024.03

Research paper (scientific journal), Joint Work, Accepted, ISSN 13480685

The purpose of this study was to clarify the effect of winter indoor thermal environment on the health for Child-Rearing Age Women. Follow-up surveys on Residents' health and indoor thermal environment were conducted in winter(2015-2022) before, after and 5-6years after moving to houses with thermal insulation performance. Repeated measure analysis of variance showed that increased indoor temperature reduce the symptoms such as cough and phlegm, stuffy or runny nose, stiff shoulders, back pain, cold extremities, injury, and catching a cold. It also improved subjective sleep quality and subjective health status.

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Association between indoor temperature during winter and falls at home in the past year among community-dwelling older adults: A cross-sectional analysis of the nationwide Smart Wellness Housing survey in Japan

Ito M., Ikaga T., Oguma Y., Saito Y., Fujino Y., Ando S., Murakami S.

Japanese Journal of Geriatrics (Japanese Journal of Geriatrics) 61 ( 2 ) 218 - 227 2024

Research paper (scientific journal), Joint Work, Accepted, ISSN 03009173

Aim: Some studies have reported a higher incidence of falls during winter with similar proportions of indoor and outdoor falls. We investigated the relationship between indoor temperature during winter and falls at home in the past year among community-dwelling older adults. Methods: This cross-sectional study enrolled 964 individuals of ≥65 years of age in Japan. Participants answered questions about falls (including trips) at home within the past year, and the living room temperature was measured for 2 weeks during winter. Participants were divided into those living in cold (mean temperature near the floor <12̊C), slightly cold (12-17.9℃), and warm (≥18̊C) houses. The association between indoor temperature (cold vs. slightly cold vs. warm houses) and falls at home in the past year was examined using a logistic regression analysis adjusted for potential confounding factors. Results: Valid data were obtained from 907 participants (mean age: 72.0±6.3 years), of whom 265,553, and 89 lived in cold, slightly cold, and warm houses, respectively. In the past year, falls occurred once in 325 (35.8%) participants and multiple times in 148 (16.3%) participants. In warm houses, the odds ratio of falling once and multiple times in the past year was 0.49 (p=0.032) and 0.34 (p=0.035), respectively, in comparison to cold houses. Conclusions: Living in cold houses may be associated with an increased risk of falling at home among older adults. Maintaining an appropriate indoor thermal environment during winter may reduce the risk of falling among individuals who spend most of their time at home.

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PV/T solar panel for supplying residential demands of heating/cooling and hot water with a lower environmental thermal load

Kohei Terashima, Haruki Sato, Toshiharu Ikaga

Energy and Buildings (Elsevier BV) 297 113408 - 113408 2023.10

Research paper (scientific journal), Joint Work, Last author, Accepted, ISSN 0378-7788

The practical efficiencies of existing commercial m-Si and CIS PV modules measured in reality by our group were less than 15 % because of the higher temperatures of the PV modules, and the rest of more than about 85 % of solar energy would be the exhaust heat to the environment. It was already reported in 2020 that the principle of an environmentally-friendly PV/T (Photovoltaic/Thermal) solar panel using an m-Si PV module to utilize 71.3 % solar energy for electricity and 40 °C hot water, as well as suppress heat radiation from the panel. The panel was designed to confirm the principle, i.e., it was an experimental PV/T solar panel. In this paper, a new practical environmentally-friendly PV/T solar panel is proposed for aiming the application to BIPVT (Building-integrated Photovoltaic/Thermal) systems. The new panel uses a CIS PV module, and all the functions, including a heat exchanger using flat aluminum tubes, are placed in the panel box, which is almost the same size as a simple CIS PV panel. The proposed PV/T solar panel converts 73.5 % of solar energy with 13.0 % power generation efficiency and 60.5 % heat collection efficiency at a 40 °C hot water supply in Yokohama, Japan. The efficiency is higher than the previous experimental panel. The proposed panel also can suppress heat radiation at about 50 °C even in the case of 60 °C hot water supply. The proposed PV/T solar panel can supply all residential heat demands, such as domestic hot water (DHW) and space heating or cooling, using solar heat with a lower environmental thermal load.

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Economic benefits of the effects of office environment on perceived work efficiency and presenteeism

Shiro Arata, Masaki Sugiuchi, Toshiharu Ikaga, Yasuyuki Shiraishi, Tatsuya Hayashi, Shintaro Ando, Shun Kawakubo

Building and Environment (Elsevier BV) 243 110712 - 110712 2023.08

Research paper (scientific journal), Joint Work, Accepted, ISSN 0360-1323

As hubs of intellectual activity, offices are expected to promote work efficiency and support worker health. Many studies have analyzed the relationship of the office environment with work efficiency and the health of workers. However, few studies have compared the effects of various elements of the office environment on these outcomes and their economic benefits. To address this limitation, this study investigated the impact of various environmental elements on both work efficiency and health, and analyzed the economic benefits of optimizing these elements in office spaces. The impacts of each element of the office environment on work efficiency and worker health were analyzed for 1644 workers in 29 office buildings in Tokyo, Japan. Economic benefits were estimated by comparing perceived work efficiency to an ideal office and presenteeism to the absence of health-related barriers. The results showed that the office interior and furnishings provided the largest estimated economic benefits, followed by overall building sanitation and HVAC airflow. These elements produced economic benefits associated with high perceived work efficiency. The largest estimated economic benefits associated with low presenteeism was from desk lighting, which was the fourth largest economic benefit overall. The results suggest that healthy offices require not only improvements but also the removal of negative elements. These findings are expected to contribute to the realization of comfortable, healthy offices.

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Accelerometer-assessed physical activity of elementary schoolers in Kawasaki city

Baba Akiko, Oguma Yuko, Ito Maki, Kaneko Masashi, Ikaga Toshiharu

Research in Exercise Epidemiology (Japanese Association of Exercise Epidemiology) 25 ( 1 ) 126 - 127 2023.06

Research paper (scientific journal), Joint Work, Accepted, ISSN 13475827

Accelerometer-assessed physical activity of junior high schoolers in Tokyo, Hiroshima, and Kochi

Baba Akiko, Oguma Yuko, Ito Maki, Ikaga Toshiharu

Research in Exercise Epidemiology (Japanese Association of Exercise Epidemiology) 25 ( 1 ) 128 - 129 2023.06

Research paper (scientific journal), Joint Work, Accepted, ISSN 13475827

断熱改修が成人における冬季の住宅内座位行動および身体活動に及ぼす影響　スマートウェルネス住宅調査による準実験的研究

伊藤真紀, 伊香賀俊治, 小熊祐子, 齋藤義信, 藤野善久, 安藤真太朗, 村上周三

運動疫学研究: Research in Exercise Epidemiology (日本運動疫学会) 25 ( 1 ) 50 - 63 2023.06

Research paper (scientific journal), Joint Work, Accepted, ISSN 1347-5827

目的:断熱改修が冬季の住宅内の座位行動と身体活動に及ぼす影響を検討した。方法:断熱改修に意欲的な成人を募集し,冬季2週間のベースライン調査(改修前)と,その1～4年後の同時期に追跡調査(改修後)を行った。住宅内の座位時間と低強度以上の身体活動量(light-to-vigorous physical activity;LVPA)は,加速度計と外出記録から評価した。断熱改修を行った介入群と断念した対照群に対象者を分け,住宅内の座位時間とLVPAの変化との関連を線形混合モデルで検討した。また,脱衣所室温変化量[低下(-1℃未満),変化なし(-1℃以上+1℃未満),上昇小(+1℃以上+5℃未満),上昇大(+5℃以上)]を説明変数に加えた解析も実施した。結果:1,751名(介入群1,640名,対照群111名)を解析対象とした。脱衣所室温は介入群で有意に上昇したが,群間で調査期間のずれが生じたことなどにより,対照群の室温も外気温の上昇に伴い上昇していた。多変量解析の結果,断熱改修と住宅内の座位時間・LVPAの変化に有意な関連は認められなかった。ただし,脱衣所室温変化量は有意に関連していた。室温が変化しなかった場合に比べて,5℃以上改善した場合は,座位時間が減少し,LVPAは増加したが,室温が低下した場合には,座位時間が増加し,LVPAは減少した。結論:断熱改修は住宅内の座位時間とLVPAの変化に関連していなかった。ただし,脱衣所等の室温改善は,住宅内の座位行動を抑制し,LVPAを増加させる可能性が示唆された。今後も検証が必要である。(著者抄録)

東日本大震災被災地域の高齢者における住居形態と住環境リスクに関する観察研究　the RIAS Study

鈴木るり子, 坪田恵[宇津木], 佐々木亮平, 下田陽樹, 藤野善久, 伊香賀俊治, 狩野徹, 坂田清美

日本公衆衛生雑誌 (日本公衆衛生学会) 70 ( 2 ) 99 - 111 2023.02

Research paper (scientific journal), Joint Work, Accepted, ISSN 0546-1766

目的「住まい」は人が最も長く曝露を受ける場である。厚生労働省は地域包括ケアシステムの取り組みの中で,土台としての高齢者のプライバシーと尊厳が十分に守られた住環境,すなわち騒音やカビ等の「住まい(以下「物理環境」)」,住居状況や社会的支援等の関わりの「住まい方(以下「社会環境」)」の重要性を基本的要素として掲げている。本研究は,災害公営住宅への移転も進んだ2018年度の被災高齢者を対象に,現在の住居形態と「物理環境」「社会環境」の関連を明らかにすることを目的とした。方法 2011年度に岩手県沿岸部で実施した大規模コホート研究(RIAS Study)に参加した65歳以上のうち,2018年度調査票の回答者3,856人を対象とした。現在の住居形態に関する設問から住居形態は以下の分類とした:"震災前と同じ(同所再建含)","仮設・みなし仮設","災害公営住宅","新所新築","その他"。「物理環境」については,国土交通省が行うスマートウェルネス住宅等推進調査事業における住宅健康チェックリストを用い,「社会環境」については,RIAS調査票より,独居,ソーシャルネットワーク,ソーシャルキャピタルについて評価した。"震災前と同じ(同所再建含)"と比較した他の住居形態と,「物理環境」「社会環境」の各項目の関連を,多変量ロジスティック回帰分析,重回帰分析より検討した。結果最終的な解析対象は3,856人(男性39.1%,平均年齢74.6歳)であった。住居形態と「物理環境」の関連では,震災前と同じ群と比較し,新所新築,災害公営住宅,その他の群で住まいの健康度が高く,仮設・みなし仮設群の健康度が低かった。一方,「社会環境」との関連では,震災前と同じ群と比較し,災害公営住宅群で独居者が有意に多く,災害公営住宅,新所新築群でソーシャルキャピタルが有意に低かった。また,ソーシャルネットワークでは,震災前と同じ群と比較し,災害公営住宅群で有意に低く,サポートの内訳では,災害公営住宅群では家族からのサポート,新所新築群では友人からのサポートが有意に低かった。結論高齢者においては,特に既存コミュニティの有無にかかわらず新たな土地でソーシャルキャピタルやソーシャルネットワークを築くことが難しいことが示された。地域に出るきっかけづくりを含む,長期的な高齢者支援のあり方について早急な取り組みが求められる。(著者抄録)

SMART WELLNESS HOUSING AND BLOOD PRESSURE CONTROL

Umishio, W; Ikaga, T; Kario, K

JOURNAL OF HYPERTENSION 41 E14 - E14 2023.01

Research paper (scientific journal), Joint Work, Accepted, ISSN 0263-6352

EFFECTS OF AIR CONDITIONING SYSTEM ON HEALTH SYMPTOMS AND QUALITY OF LIFE IN RESIDENTS OF HOUSES

梅本大輔, 関谷佳子, 中川浩, 上林清香, 伊香賀俊治

日本建築学会環境系論文集(Web) (Journal of Environmental Engineering (Japan)) 88 ( 806 ) 325 - 333 2023

Research paper (scientific journal), Joint Work, Last author, Corresponding author, Accepted, ISSN 1881-817X

Indoor temperature environment and air quality affect the health of residents of houses, and thus efforts are underway to improve the insulation of houses. In this study, we conducted a questionnaire survey to investigate changes in health symptoms and quality of life after moving into a house with a central air conditioner, floor heating, and room air conditioners. The results revealed that residents of houses with central air conditioning tended to have a higher rate of improvement in health symptoms and quality of life compared with other types of air conditioning.

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Validity Verification of Work Environment Subjective Assessment Tool for Improving the Efficiency and Health of Workers: Part 2-Changes in Health and Work Efficiency Before and After the Covid-19 Pandemic

森重優子, 白石靖幸, 安部祐子, 林立也, 伊香賀俊治, 藤野善久

空気調和・衛生工学会論文集 48 ( 313 ) 35 - 43 2023

Research paper (scientific journal), Joint Work, Accepted, ISSN 0385-275X

EFFECTS OF DIFFERENT OFFICE COOLING SYSTEMS ON WORKERS (PART 2): ANALYSIS OF PHYSIOLOGICAL AND PSYCHOLOGICAL PARAMETERS AND SIMULATED WORK PERFORMANCE DURING SUMMER, WITH A FOCUS ON INDIVIDUAL ATTRIBUTES

臼倉里津, 伊香賀俊治, 清水洋, 佐藤啓明, 川上梨沙, 伊藤清

日本建築学会環境系論文集(Web) (Journal of Environmental Engineering (Japan)) 88 ( 807 ) 387 - 396 2023

Research paper (scientific journal), Joint Work, Corresponding author, Accepted, ISSN 1881-817X

The working space environment has a large impact on workers. To improve workplace productivity, it is important to design the office environment. In this paper, we focused on radiant air conditioning, which is attracting increasing attention for use in offices. The purpose of this study was to determine the differences in indoor environment between radiant air conditioning and convective air conditioning and evaluate their effects on workplace productivity by conducting subject experiments. Radiant air conditioning was found to reduce differences between deep body temperature and terminal skin temperature and to improve creative work performance compared with convection air conditioning.

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EFFECT OF UNIFORM THERMAL ENVIRONMENT WITH CENTRAL AIR CONDITIONING ON RESIDENT SLEEP INDEX

梅本大輔, 関谷佳子, 中川浩, 上林清香, 河本紗弥, 伊香賀俊治

日本建築学会環境系論文集(Web) (Journal of Environmental Engineering (Japan)) 88 ( 807 ) 429 - 438 2023

Research paper (scientific journal), Joint Work, Last author, Corresponding author, Accepted, ISSN 13480685

The thermal environment of a house is a factor that affects sleep quality. Thus, for maintaining good health, it is important for houses to have an appropriate thermal environment. The influence of ventilation and air conditioning on a house's thermal environment cannot be ignored. Here, we investigated differences in ventilation and air conditioning equipment by comparing and evaluating the sleep quality of residents using individual air conditioners or central air conditioning. The results suggested that the central air conditioning group had reduced sleep latency, which might increase sleep efficiency in summer.

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住宅の温熱環境と高齢者の健康

伊香賀俊治

Applied Gerontology (Society for Applied Gerontology - Japan) 17 ( 1 ) 4 - 8 2023

Research paper (scientific journal), Joint Work, Accepted, ISSN 18826245

国土交通省は2014年度より、厚生労働省と連携して「スマートウェルネス(健康・省エネ)住宅等推進事業調査」を実施しており、著者はこの調査を行っている医学・建築学の専門家約90名で構成される委員会の幹事と調査解析小委員会の委員長を務めている。同事業調査では、断熱改修等による住まいの改善が居住者の健康に与える影響に関する2千世帯・4千人規模の全国調査(SWH全国調査)を実施し、2023年6月現在で医学系原著論文11編が刊行されている。本稿では、それらの概要と著者らによるその他の成果について紹介した。SWH全国調査では、亜熱帯の沖縄県を除く全国2190世帯の居間、寝室、脱衣所の冬季室温を測定した。その結果、WHO勧告冬期最低室温18℃以上を、在宅中の居間平均室温で満たさない住まいが9割を占めることが明らかになった。その他、断熱改修による暖かい住まいが、高血圧緩和、血圧変動緩和、心電図異常所見の予防、脂質異常症の予防、過活動膀胱の予防、睡眠の質向上、健康関連QOLの向上、座りすぎ生活の減少、につながることについて概説した。

Effect of insulation retrofitting on sedentary behavior and physical activity at home among adults in winter: a quasi-experimental study of the Nationwide Smart Wellness Housing Survey in Japan

Ito Maki, Ikaga Toshiharu, Oguma Yuko, Saito Yoshinobu, Fujino Yoshihisa, Ando Shintaro, Murakami Shuzo, the Smart Wellness Housing Survey group

Research in Exercise Epidemiology (Japanese Association of Exercise Epidemiology) advpub 2023

Research paper (scientific journal), Joint Work, Accepted, ISSN 1347-5827

Objective: We aimed to examine the effects of insulation retrofitting on sedentary behavior time (SBT) and light-to-vigorous physical activity (LVPA) at home in adults during winter.
 Methods: Adults intending to retrofit their insulation participated in a 14-day baseline survey in winter and a follow-up survey 1–4 years after retrofitting. Participants were classified into an intervention (insulation retrofitting) or a control (non-insulation retrofitting) group. SBT and LVPA changes were calculated using an accelerometer and questionnaires. A multilevel model was fitted to estimate the effects of insulation retrofitting on these changes. As a secondary analysis, the change in dressing room temperature (Td) from baseline was added as an independent variable in the model, categorized as a decrease in Td (<-1.0°C), no change in Td (-1.0°C to +0.9°C), a small increase in Td (+1.0°C to +4.9°C), and a large increase in Td (≥+5.0°C).
 Results: Of the 1751 participants, 1640 were in the intervention group. Both groups experienced an increase in Td. The intervention group experienced a slight increase in outside temperature, whereas the control group experienced a significant increase in outside temperature. Insulation retrofitting was not significantly associated with SBT and LVPA at home; however, the change in Td was significantly associated with SBT and LVPA. Compared to no change in Td, the large increase in Td was associated with a decrease in SBT and an increase in LVPA. In contrast, the decrease in Td was associated with an increase in SBT and a decrease in LVPA.
 Conclusion: Insulation retrofitting was not associated with changes in SBT and LVPA in adults during winter. However, improving room temperature, including Td, could potentially decrease SBT and increase LVPA in adults. Further research is needed to confirm the effect of insulation retrofitting on SBT and LVPA.

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Resiliency evaluation of a collective residence with an independent power outage system

Jungmin Kim, Toru Shiba, Toshiharu Ikaga, Takashi Akimoto, Shin-Ichi Tanabe

JAPAN ARCHITECTURAL REVIEW (WILEY) 6 ( 1 ) 1 - 15 2022.11

Research paper (scientific journal), Joint Work, Accepted, ISSN 2475-8876

This study aimed to verify the effectiveness of a 48-h independent power outage system, evaluate the indoor thermal environment under power outage conditions, and improve residential awareness of disasters through a power outage experience. A power outage experiment was conducted in a collective residence with a 48-h independent power system. The available power for each dwelling unit was limited based on the type of heat source, at 700 and 1200 W for cogeneration (CG) and solid oxide fuel cell (SOFC) heating, respectively. The power supply was halted when the available power limit was exceeded. During the experiment, the thermal environment, temperature, humidity, amount of power generated by the CG and SOFC, and load power of the dwelling units were analyzed. We also conducted a questionnaire survey to evaluate the indoor environment and infrastructure. The results showed that home appliances could be used because all dwelling units were supplied with sufficient power, at 700 and 1200 W. The most important appliances were electric fans, refrigerators, lighting, mobile phones, and computer chargers. Therefore, the experiment demonstrated that a comfortable evacuation living condition can be realized by using CG and SOFC during a power outage in the summer.

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[Environmental risks to housing and living arrangements among older survivors of the Great East Japan Earthquake and their relationships with housing type: The RIAS Study].

Ruriko Suzuki, Megumi Tsubota-Utsugi, Ryohei Sasaki, Haruki Shimoda, Yoshihisa Fujino, Toshiharu Ikaga, Toru Kano, Kiyomi Sakata

[Nihon koshu eisei zasshi] Japanese journal of public health (Japanese Society of Public Health) advpub ( 2 ) 99 - 111 2022.10

Research paper (scientific journal), Joint Work, Accepted, ISSN 0546-1766

Objective Over the course of their lives, people spend most of their time in the home environment. The Community-based Integrated Care System 2018 by the Ministry of Health, Labour and Welfare in Japan declared the importance of "housing" and "living arrangements" as essential elements to enable older adults to live independently and to protect their privacy and dignity in their communities. The present study aims to clarify the relationship between current housing type and "housing" and "living arrangements" among older survivors of the Great East Japan Earthquake (GEJE).Methods We used data obtained from 3,856 participants, aged 65 years or older, in the Research project for prospective Investigation of health problems Among Survivors of the GEJE (RIAS). Housing types were categorized as follows: "same housing," "temporary housing," "disaster public housing," "new housing" (in a different area), and "others." Healthy housing scores were calculated using a housing health checklist from the Nationwide Smart Wellness Housing Survey in Japan. "Living arrangements" were assessed based on residential status, social network, and social capital. To determine the risks associated with each "housing" and "living arrangement" category, we used multivariate logistic and linear regression models.Results The number of participants in each housing type was as follows: 2,531 in "same housing," 146 in "temporary housing," 234 in "disaster public housing," 844 in "new housing," and 101 in "others." Compared with those living in "same housing," those living in "disaster public housing," "new housing," and "others" had a significantly higher healthy housing score, whereas those living in "temporary housing" had a lower score. However, with regards to "living arrangements," the number of residents who were living alone was significantly higher among those in "disaster public housing," and those living in "disaster public housing" as well as "new housing" had low social capital compared with those living in "same housing." The likelihood of having a poor social network was substantially higher for those living in "disaster public housing." Sub-scale analyses indicated that "disaster public housing" was associated with less family support, whereas "new housing" was associated with less support from friends.Conclusion The present results indicate that older survivors-regardless of whether they live in the existing community-find it challenging to establish new social capital and social networks in a new location without the presence of "someone" they knew before the disaster.

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Role of housing in blood pressure control: a review of evidence from the Smart Wellness Housing survey in Japan.

Wataru Umishio, Toshiharu Ikaga, Kazuomi Kario, Yoshihisa Fujino, Masaru Suzuki, Shintaro Ando, Tanji Hoshi, Takesumi Yoshimura, Hiroshi Yoshino, Shuzo Murakami

Hypertension research : official journal of the Japanese Society of Hypertension (SPRINGERNATURE) 46 ( 1 ) 9 - 18 2022.10

Research paper (scientific journal), Joint Work, Accepted, ISSN 0916-9636

Current countermeasures for preventing hypertension emphasize only improvements to lifestyle. Recently, improving life environment has attracted attention, in parallel with publication of the WHO Housing and health guidelines. We quantitatively evaluated the relationship between housing thermal environment and blood pressure (BP) in a real-world setting. We conducted a nationwide, prospective intervention study-the Smart Wellness Housing survey-in Japan, as a non-randomized controlled trial. The intervention was the retrofitting of thermal insulation in houses. Participant recruitment was done by construction companies in all 47 prefectures of Japan. Measurements of home BP and indoor temperature at 1.0 m above the floor in the living room, changing room, and bedroom were taken for 2 weeks before and after the intervention each winter (November-March) of FY 2014-2019. As of July 2022, over 2500 households and 5000 participants were registered in the database. We found that (1) about 90% of Japanese lived in cold homes (minimum indoor temperature <18 °C), (2) indoor temperature was non-linearly associated with home BP, (3) morning systolic BP (SBP) was more sensitive than evening SBP to changes in indoor temperature, (4) SBP was influenced by indoor temperature change particularly in older participants and women, (5) unstable indoor temperature was associated with large BP variability, and (6) insulation retrofitting intervention significantly reduced home BP, especially in hypertensive patients. We proposed that the BP reduction effect of the life-environment is comparable to that achievable by lifestyle.

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Influence of residential performance on residents' health status (part II): Nationwide survey of environmental performance of apartment buildings and residents' health status

Shun Kawakubo, Tomomitsu Kamata, Shuzo Murakami, Toshiharu Ikaga, Tanji Hoshi, Shintaro Ando

JAPAN ARCHITECTURAL REVIEW (WILEY) 5 ( 4 ) 576 - 591 2022.10

Research paper (scientific journal), Joint Work, Accepted, ISSN 2475-8876

The residential environment clearly affects health. For example, a previous study has established relationships between specific environmental factors and the health status of residents in detached houses. However, studies focused on apartment buildings are still insufficient. Therefore, in this study, a large nationwide questionnaire survey of residents of apartments was conducted. The residential environment was subjectively evaluated using a Japanese Comprehensive Assessment System for Built Environment Efficiency (CASBEE) tool: the CASBEE Health Checklist. The results showed that residents living in apartments who score higher on the checklist tend to have a lower prevalence of various diseases, indicating that residential environment may be an important determinant of health. Furthermore, the odds ratios for residents living in apartment buildings were lower for diabetes mellitus, hypertensive diseases, heart diseases, cerebrovascular diseases, chronic lower respiratory diseases, and inflammatory polyarthropathies compared with residents living in detached houses. These findings support the general link between the residential environment and residents' health and suggest that housing typology is an important factor.

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EFFECT OF INDOOR HEATING SYSTEM AND THERMAL ENVIRONMENT ON SEDENTARY BEHAVIOR IN WINTER

MYONAI Katsuhiro, IKAGA Toshiharu, ITO Maki, KOJIMA Hiroshi

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 87 ( 799 ) 579 - 587 2022.09

Research paper (scientific journal), Joint Work, Corresponding author, Accepted, ISSN 1348-0685

Physical activity contributes to a variety of health benefits. Therefore, preventing sedentary behavior is critical for the promotion of physical activity in people of all ages. This study was to clarify the relationship between sedentary behavior and the living environment. This study surveyed residents living in houses with adequate insulation performance. In the cross-sectional survey, we examined the relationship between living environment and sedentary behavior at the daily and individual levels, using multilevel analysis. In the intervention survey, we examined the relationship between changes in the indoor thermal environment and sedentary behavior by requesting the active use of heating.

MULTIVARIATE ANALYSIS ON STUDENTS’ PHYSICAL ACTIVITY INFLUENCED BY THE ELEMENTARY SCHOOL FACILTY ENVIRONMENT

KANEKO Masashi, IKAGA Toshiharu, BABA Akiko

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 87 ( 799 ) 559 - 568 2022.09

Research paper (scientific journal), Joint Work, Corresponding author, Accepted, ISSN 1348-0685

The decline in physical fitness among elementary school students has become a social problem, and there is a need to promote physical activity in these students. The promotion of physical activity also has an impact on health and learning. In this study, we examined the effects of the elementary school facility environment on the physical activity of students, using a questionnaire survey and actual measurements of physical activity. The analysis results suggested that students at elementary schools having a good schoolyard environment walked more and that the operation of the school affects student’s school-time step counts.

INFLUENCE OF THERMAL INSULATION PERFORMANCE OF HOUSES ON PHYSIOLOGICAL RESPONSES AND REMOTE WORKING PERFORMANCE

KOMOTO Saya, IKAGA Toshiharu, MITSUKURA Yasue, YOSHIDA Satoshi, IKEDA Tomoyuki

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 87 ( 798 ) 492 - 502 2022.08

Research paper (scientific journal), Joint Work, Corresponding author, Accepted, ISSN 1348-0685

It is important to prevent hypertension, which is a risk factor for cardiovascular disease and severe COVID-19. In addition, as more people work from home, it is desirable to improve intellectual productivity at home. Therefore, in this study, we clarify the effects of the thermal insulation performance of houses on physiological responses and productivity in remote workers. We obtained the following findings. (1) When insulation performance was higher, systolic blood pressure was lower, and the skin temperature and the blood flow rate of the feet were higher; (2) As insulation performance increased, productivity increased.

HIGH RISK RESIDENTS OF COLD EXPOSURE AT WAKING AND BEDTIME: Indoor temperature measurement of 980 people in the same municipality

FUKUZUMI Yasuhiro, ANDO Shintaro, IKAGA Toshiharu, UMISHIO Wataru, NAKAGAWA Asahi, HOSHI Tanji

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 87 ( 797 ) 472 - 481 2022.07

Research paper (scientific journal), Joint Work, Accepted, ISSN 1348-0685

A field survey using actual indoor temperature measurements and questionnaires was conducted in Yusuhara, Kochi Prefecture, in November 2019. Based on the field survey, ordinal logistic regression analysis was conducted to identify common characteristics of residents living in a cold environment at waking and before bedtime. Low insulation performance, the type of heating equipment used such as electric heater and air conditioners, and personal attributes such as age, number of people in the household and length of time at home were significant risk factors for living in cold houses.

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Association between Indoor Temperature in Winter and Serum Cholesterol: A Cross-Sectional Analysis of the Smart Wellness Housing Survey in Japan.

Wataru Umishio, Toshiharu Ikaga, Kazuomi Kario, Yoshihisa Fujino, Masaru Suzuki, Tanji Hoshi, Shintaro Ando, Takesumi Yoshimura, Hiroshi Yoshino, Shuzo Murakami

Journal of atherosclerosis and thrombosis (Journal of Atherosclerosis and Thrombosis) 29 ( 12 ) 1791 - 1807 2022.05

Research paper (scientific journal), Joint Work, Corresponding author, Accepted, ISSN 13403478

AIM: Issuance of the WHO Housing and health guidelines has paralleled growing interest in the housing environment. Despite accumulating evidence of an association between outdoor temperature and serum cholesterol, indoor temperature has not been well investigated. This study examined the association between indoor temperature and serum cholesterol. METHODS: We collected valid health checkup data of 2004 participants (1333 households), measured the indoor temperature for 2 weeks in winter, and divided participants according to whether they lived in a warm (average bedroom temperature ≥ 18℃), slightly cold (12-18℃) or cold house (＜12˚C). The relationship between bedroom temperature and serum cholesterol was analyzed using multivariate logistic regression models, adjusting for demographics, lifestyle habits and the season in which the health checkup was conducted, with a random effect of climate areas in Japan. RESULTS: The sample sizes for warm, slightly cold, and cold houses were 206, 940, and 858, respectively. Compared to those in warm houses, the odds ratio of total cholesterol exceeding 220 mg/dL was 1.83 (95%CI: 1.23-2.71, p=0.003) for participants in slightly cold houses and 1.87 (95%CI: 1.25-2.80, p=0.002) in cold houses. Similarly, the odds ratio of LDL/non-HDL cholesterol exceeding the standard range was 1.49 (p=0.056)/1.67 (p=0.035) for those in slightly cold houses and 1.64 (p=0.020)/1.77 (p=0.021) in cold houses. HDL cholesterol and triglycerides were not significantly associated with bedroom temperature. CONCLUSION: Besides lifestyle modification, improving indoor thermal environment through strategies such as installing high thermal insulation and appropriate use of heating devices may contribute to better serum cholesterol condition.

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Frontotemporal EEG as potential biomarker for early MCI: a case-control study.

Yasue Mitsukura, Brian Sumali, Hideto Watanabe, Toshiharu Ikaga, Toshihiko Nishimura

BMC psychiatry (BMC) 22 ( 1 ) 289 - 289 2022.04

Research paper (scientific journal), Joint Work, Accepted

BACKGROUND: Previous studies using EEG (electroencephalography) as biomarker for dementia have attempted to research, but results have been inconsistent. Most of the studies have extremely small number of samples (average N = 15) and studies with large number of data do not have control group. We identified EEG features that may be biomarkers for dementia with 120 subjects (dementia 10, MCI 33, against control 77). METHODS: We recorded EEG from 120 patients with dementia as they stayed in relaxed state using a single-channel EEG device while conducting real-time noise reduction and compared them to healthy subjects. Differences in EEG between patients and controls, as well as differences in patients' severity, were examined using the ratio of power spectrum at each frequency. RESULTS: In comparing healthy controls and dementia patients, significant power spectrum differences were observed at 3 Hz, 4 Hz, and 10 Hz and higher frequencies. In patient group, differences in the power spectrum were observed between asymptomatic patients and healthy individuals, and between patients of each respective severity level and healthy individuals. CONCLUSIONS: A study with a larger sample size should be conducted to gauge reproducibility, but the results implied the effectiveness of EEG in clinical practice as a biomarker of MCI (mild cognitive impairment) and/or dementia.

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Quantitative Evaluation of the Contributions of Improved Housing Performances Toward Delivering Sustainable Development Goals by a Building Energy Simulation Tool

Mao Serikawa, Makoto Satoh, Wataru Umishio, Shun Kawakubo, Junta Nakano, Takashi Akimoto, Toshiharu Ikaga, Shuzo Murakami

Sustainable Cities and Society (ELSEVIER) 79 2022.04

Research paper (scientific journal), Joint Work, Accepted, ISSN 2210-6707

In 2015, the 2030 Agenda for Sustainable Development Goals (SDGs) was adopted by all United Nations Member States. The indoor environment of residences affects the health of occupants regarding SDG 3 (Good Health and Well-being). Meanwhile, a vast amount of energy is used to supply power to houses worldwide, which emit sufficient volumes of CO2 and affect climate change regarding SDG 7 (Affordable and Clean Energy) and SDG 13 (Climate Action). A key step to delivering on these SDGs is improving the thermal insulation of houses and housing equipment performance to reduce energy consumption and protect the health of the occupants by improving the indoor environment. This study presents an evaluation method for quantifying the contribution of improving housing performance toward delivering the SDGs. The proposed approach is primarily based on the results of heat load simulations. Meanwhile, blood pressure is predicted as an indicator of health by using the interior environment obtained by the simulation. A case study was performed, and the results demonstrated the effectiveness of improving the housing performance of newly constructed houses compared to heating and retrofit. The proposed method is versatile and can be adjusted for application to alternative locations, house designs, and lifestyles.

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冬季における住宅内室温と外気温の実態とその関連　SWH横断調査

星旦二, 伊香賀俊治, 海塩渉, 藤野善久, 安藤真太朗, 吉村健清

日本公衆衛生雑誌 (日本公衆衛生学会) 69 ( 4 ) 297 - 306 2022.04

Research paper (scientific journal), Joint Work, Accepted, ISSN 0546-1766

目的本研究の目的は,我が国の冬期における戸建て住宅各室の室温と外気温の実態と共にその関連性について,国土交通省の定める省エネ地域区分別に明確にすることである。方法本研究の対象者は,日本全国に居住している3,781人である。調査は2014年度冬季より,国土交通省の支援を得て全国的に実施されている,SWH(Smart Wellness Housing)事業の一環として5年間実施した。各部屋別(居間・寝室・脱衣所)に測定された冬期二週間の床上1m室温と床近傍室温,それに気象庁が測定した外気温の実態とともに,その関連について共分散構造分析を用いて解析した。これらの関連は,同時分析により全国の省エネ地域区分別に解析した。分析ソフトは,SPSS22.0とAMOS22.0を用いた。結果冬季における住居内床近傍室温は床上1m室温よりも低く,時間帯でみると床近傍ないし室温共に朝が低い温度を示した。部屋別室温較差は,居間と脱衣所間で大きかった。室温を地域別にみると,省エネ地域2の室温が最も高く,省エネ地域4の室温が最も低いことが示された。冬期の外気温は各室温よりも床近傍室温と強い関連がみられた。結論我が国の住宅床近傍室温は,床上1m室温よりも低いことと,居間と脱衣所とでは大きな温度較差がみられた。省エネ地域区分4の住宅床近傍室温と床上1m室温が最も低いことが示された。室温が外気温から影響される度合いは,省エネ地域7を除き地域番号とともに大きくなることが示された。(著者抄録)

Proposal of net-zero energy house by introducing environmentally friendly PV/T solar panels

TERASHIMA Kohei, SATO Haruki, IKAGA Toshiharu

Journal of Japan Solar Energy Society (Japan Solar Energy Society) 48 ( 2 ) 61 - 70 2022.03

Research paper (scientific journal), Joint Work, Last author, Corresponding author, Accepted, ISSN 0388-9564

Solar energy would be the most important energy resource. The highest performance solar-energy receiver recorded utilizing 74.3 % of the solar energy in total of electricity and 40 °C hot water in summer, Yokohama, Japan, has already been reported in 2020 as a photovoltaic/Thermal (PV/T) solar panel. In this paper, the system design on introducing the PV/T solar panel to be a part of energy-supply system in a household and the simulation results are reported. Using a Monte Carlo simulation method, it can generate different energy demands at every 15 minutes through a year for various family members as the simulation calculation, while the results always follow the input existing statistics information. Not only solar-energy management in a household but also the environmental thermal load is evaluated. An example of the net-zero energy house having the best combination of the environmentally friendly PV/T and PV solar panels is presented in this paper.

Descriptive epidemiology of winter indoor and outdoor temperatures and their relationships based on SWH survey

HOSHI Tanji, IKAGA Toshiharu, UMISHIO Wataru, FUJINO Yoshihisa, ANDO Shintaro, YOSHIMURA Takesumi

Nihon Koshu Eisei Zasshi(JAPANESE JOURNAL OF PUBLIC HEALTH) (Japanese Society of Public Health) advpub ( 4 ) 297 - 306 2022

Research paper (scientific journal), Joint Work, Accepted, ISSN 0546-1766

Objectives The purpose of this study was to make clear the descriptive epidemiology and the relationship between the room temperature of living room, bedroom, dressing room, and outdoor during winter, based on the climate areas in Japan.

Methods This study targeted 3,781 people, survey for 5 years from 2014, based on the Smart Wellness Housing (SWH) project, which was carried out nationwide with the support of the Ministry of Land, Infrastructure, Transport and Tourism. During winter, we recorded the outdoor temperature and living room, bedroom, and dressing room temperatures at 1 m above the floor and near the floor for two weeks. Covariance structure analyses were used to clarify the relationship between room temperature and outdoor temperature based on six climate areas in Japan. The analyses were performed using SPSS22.0 and AMOS22.0 for Windows.

Results The temperature near the floor inside the house was lower than the room temperature at 1 m above the floor, and both the room and near the floor temperature in the morning tended to be the lowest. The temperature disparity between the dressing room and living room was the largest. Based on climate areas, the room temperature in the Area 2 was the highest, while the room temperature in the Area 4 was the lowest. The outdoor temperature was more closely associated with the room temperature near the floor than the room temperature at 1 m above the floor, especially in the southern Areas, except Area 7.

Conclusion The temperature near the floor inside the house was lower than room temperature at 1 m above the floor. The temperature disparity between dressing room and living room was the largest. The room temperature and near the floor temperature were lowest in the energy-saving Area 4. The outdoor temperature was more closely associated with the room temperature near the floor than the room temperature at 1 m above the floor, especially in the southern Areas, except Area 7.

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CASBEE-オフィス健康チェックリストを用いたWEBアンケートの追跡調査結果

森重優子, 白石靖幸, 安部祐子, 林立也, 伊香賀俊治, 藤野善久

空気調和・衛生工学会大会学術講演論文集 (公益社団法人空気調和・衛生工学会) 2022.8 93 - 96 2022

Research paper (scientific journal), Joint Work, Accepted, ISSN 1880-3806

近年、地域や職場等を通じた健康増進への働きかけが注目されている。この流れより執務環境の主観評価ツールであるCASBEE-OHCの開発とそのチェックリストを用いたWEBアンケート調査が行われた。しかし現在、オフィス環境やワーカーを取り巻く環境の変化が予想される。そこで本研究では、現在の環境について新たな知見を得るため、再度調査を実施した。結果として、現在、執務者の健康には住まいの環境や家での執務環境の影響が関係していることが確認された。

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Housing quality and behavior affect brain health and anxiety in healthy Japanese adults.

Juan Cesar D Pineda, Keisuke Kokubun, Toshiharu Ikaga, Yoshinori Yamakawa

Scientific reports (NATURE PORTFOLIO) 11 ( 1 ) 11999 - 11999 2021.12

Research paper (scientific journal), Joint Work, Accepted, ISSN 2045-2322

Countless studies in animals have shown how housing environments and behaviors can significantly affect anxiety and brain health, giving valuable insight as to whether this is applicable in the human context. The relationship between housing, behavior, brain health, and mental wellbeing in humans remains poorly understood. We therefore explored the interaction of housing quality, weekend/holiday sedentary behavior, brain structure, and anxiety in healthy Japanese adults. Whole-brain structural magnetic resonance imaging (MRI) methods based on gray matter volume and fractional anisotropy were used as markers for brain health. Correlation tests were conducted, and then adjusted for multiple comparisons using the False Discovery Rate method. Housing quality and weekend/holiday sedentary behavior were associated with fractional anisotropy, but not with gray matter volume. Fractional anisotropy showed significant associations with anxiety. Lastly, both weekend/holiday sedentary behavior and housing quality were indirectly associated with anxiety through fractional anisotropy. These results add to the limited evidence surrounding the relationship among housing, behavior, and the brain. Furthermore, these results show that behavior and housing qualities can have an indirect impact on anxiety through neurobiological markers such as fractional anisotropy.

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Electrocardiogram abnormalities in residents in cold homes: a cross-sectional analysis of the nationwide Smart Wellness Housing survey in Japan

Wataru Umishio, Toshiharu Ikaga, Kazuomi Kario, Yoshihisa Fujino, Masaru Suzuki, Shintaro Ando, Tanji Hoshi, Takesumi Yoshimura, Hiroshi Yoshino, Shuzo Murakami

Environmental Health and Preventive Medicine (SPRINGER) 26 ( 1 ) 104 - 104 2021.12

Research paper (scientific journal), Joint Work, Accepted, ISSN 1342078X

Background: Excess winter mortality caused by cardiovascular disease is particularly profound in cold houses. Consistent with this, accumulating evidence indicates that low indoor temperatures at home increase blood pressure. However, it remains unclear whether low indoor temperatures affect other cardiovascular biomarkers. In its latest list of priority medical devices for management of cardiovascular diseases, the World Health Organization (WHO) included electrocardiography systems as capital medical devices. We therefore examined the association between indoor temperature and electrocardiogram findings. Methods: We collected electrocardiogram data from 1480 participants during health checkups. We also measured the indoor temperature in the living room and bedroom for 2 weeks in winter, and divided participants into those living in warm houses (average exposure temperature ≥ 18 °C), slightly cold houses (12–18 °C), and cold houses (< 12 °C) in accordance with guidelines issued by the WHO and United Kingdom. The association between indoor temperature (warm vs. slightly cold vs. cold houses) and electrocardiogram findings was analyzed using multivariate logistic regression models, with adjustment for confounders such as demographics (e.g., age, sex, body mass index, household income), lifestyle (e.g., eating habit, exercise, smoking, alcohol drinking), and region. Results: The average temperature at home was 14.7 °C, and 238, 924, and 318 participants lived in warm, slightly cold, and cold houses, respectively. Electrocardiogram abnormalities were observed in 17.6%, 25.4%, and 30.2% of participants living in warm, slightly cold, and cold houses, respectively (p = 0.003, chi-squared test). Compared to participants living in warm houses, the odds ratio of having electrocardiogram abnormalities was 1.79 (95% confidence interval: 1.14–2.81, p = 0.011) for those living in slightly cold houses and 2.18 (95% confidence interval: 1.27–3.75, p = 0.005) for those living in cold houses. Conclusions: In addition to blood pressure, living in cold houses may have adverse effects on electrocardiogram. Conversely, keeping the indoor thermal environment within an appropriate range through a combination of living in highly thermal insulated houses and appropriate use of heating devices may contribute to good cardiovascular health. Trial registration: The trial was retrospectively registered on 27 Dec 2017 to the University hospital Medical Information Network Clinical Trials Registry (UMIN-CTR, https://www.umin.ac.jp/ctr/, registration identifier number UMIN000030601).

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Impact of indoor temperature instability on diurnal and day-by-day variability of home blood pressure in winter: a nationwide Smart Wellness Housing survey in Japan

Wataru Umishio, Toshiharu Ikaga, Kazuomi Kario, Yoshihisa Fujino, Masaru Suzuki, Shintaro Ando, Tanji Hoshi, Takesumi Yoshimura, Hiroshi Yoshino, Shuzo Murakami

Hypertension Research (Springer Science and Business Media LLC) 44 ( 11 ) 1406 - 1416 2021.11

Research paper (scientific journal), Joint Work, Accepted, ISSN 09169636

<title>Abstract</title>Home blood pressure (HBP) variability is an important factor for cardiovascular events. While several studies have examined the effects of individual attributes and lifestyle factors on reducing HBP variability, the effects of living environment remain unknown. We hypothesized that a stable home thermal environment contributes to reducing HBP variability. We conducted an epidemiological survey on HBP and indoor temperature in 3785 participants (2162 households) planning to have their houses retrofitted with insulation. HBP was measured twice in the morning and evening for 2 weeks in winter. Indoor temperature was recorded with each HBP observation. We calculated the morning-evening (ME) difference as an index of diurnal variability and the standard deviation (SD), coefficient of variation (CV), average real variability (ARV) and variability independent of the mean (VIM) as indices of day-by-day variability. The association between BP variability and temperature instability was analyzed using multiple linear regression models. The mean ME difference in indoor/outdoor temperature (a decrease in temperature overnight) was 3.2/1.5 °C, and the mean SD of indoor/outdoor temperature was 1.6/2.5 °C. Linear regression analyses showed that the ME difference in indoor temperature was closely correlated with the ME difference in systolic BP (0.85 mmHg/°C, <italic>p</italic> < 0.001). The SD of indoor temperature was also associated with the SD of systolic BP (0.61 mmHg/°C, <italic>p</italic> < 0.001). The CV, ARV, and VIM showed similar trends as the SD of BP. In contrast, outdoor temperature instability was not associated with either diurnal or day-by-day HBP variability. Therefore, residents should keep the indoor temperature stable to reduce BP variability.

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特集健康的な住まいが欲しい!-暮らしやすくて,寿命も延びる健康長寿に資する住まいと住まい方

伊香賀俊治

公衆衛生 (株式会社医学書院) 85 ( 7 ) 443 - 449 2021.07

Research paper (scientific journal), Joint Work, Accepted, ISSN 03685187

Prospective cohort study of bedroom heating and risk of common cold in children.

Ishimaru T, Mine Y, Odgerel CO, Miyake F, Kubo T, Ikaga T, Fujino Y

Pediatrics international : official journal of the Japan Pediatric Society (Wiley) 64 ( 1 ) e14755 2021.04

Research paper (scientific journal), Joint Work, Accepted, ISSN 1328-8067

BACKGROUND: In countries with mild winter climates and inadequate heating, the relationship between housing conditions and health outcomes in winter have not been well studied. The purpose of present study was to evaluate the relationship between heater type and temperature factors in the bedroom and incidence of the common cold among children in Japan. METHODS: In this prospective cohort study, we distributed baseline questionnaires and temperature loggers in December 2019 and administered follow-up questionnaires in March 2020. We recruited children under age 15 years. We performed Poisson regression analysis and logistic regression analysis. RESULTS: Of 297 participants, air conditioners were the most prevalent (n=105, 35%), followed by gas or kerosene heaters (n=50, 17%) and floor heaters (n=31, 10%). Air-conditioners were associated with higher incidence of all events related to the common cold, especially having a fever (adjusted incidence rate ratio (aIRR)=1.84, 95% confidence interval (CI): 1.41-2.40). Contrary, gas or kerosene and floor heaters showed a lower incidence rate of some events related to the common cold, such as school or nursery school absence (aIRR=0.55, 95% CI: 0.37-0.82 and aIRR=0.39, 95% CI: 0.23-0.67, respectively). Whereas bedroom temperature did not show a positive association, children who always felt cold showed a higher incidence of some events related to the common cold. CONCLUSIONS: Our findings imply that the heating approach and modal thermal comfort, such as location of heating appliances, humidity, airflow, and radiant heat, may be more important for the onset of common cold in children than bedroom temperature itself.

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成人における冬季の住宅内の暖房使用と座位行動および身体活動　スマートウェルネス住宅調査による横断研究

伊藤真紀, 伊香賀俊治, 小熊祐子, 齋藤義信, 藤野善久, 安藤真太朗, 村上周三, スマートウェルネス住宅調査グループ

運動疫学研究: Research in Exercise Epidemiology (日本運動疫学会) 23 ( 1 ) 45 - 56 2021.03

Research paper (scientific journal), Joint Work, Accepted, ISSN 1347-5827

目的:成人を対象に,冬季の暖房使用と住宅内の座位行動および身体活動の関連を検討すること。方法:本研究は横断研究である。調査は沖縄県を除く46都道府県の工務店等を通して募集した断熱改修工事予定のある住宅に居住する20歳以上の成人を対象に2014年度から2017年度までの冬季(11月〜4月)に実施し,3,874名から同意を得た。加速度計は連続14日間の装着を依頼した。行動日誌から覚醒在宅時間帯を特定し,住宅内の座位行動と身体活動を評価した。コタツおよび脱衣所暖房使用の有無と住宅内の座位行動,身体活動との関連は目的変数を対数変換したうえで,日レベル(室温,オフセット項として覚醒在宅時加速度計装着時間等),個人レベル(年齢,BM等),世帯レベル(世帯年収,同居人数等)で調整した線形混合モデル(ランダム切片モデル)を男女別に実施した。非標準化偏回帰係数は指数変換し,目的変数への関連の程度を算出した。結果:有効データは3,482名であった。多変量解析の結果,コタツを使用しない場合は住宅内の座位行動時間が約2%短く[男性:exp(B)=0.98,p=0.022,女性:exp(B)=0.98,p=0.020],その中断回数は約10%多く[男性:exp(B)=1.10,p=0.001,女性:exp(B)=1.11,p<0.001],身体活動も5〜7%多かった[男性:exp(B)=1.07,p=0.005,女性:exp(B)=1.05,p=0.012]。脱衣所を暖房する場合も同様の関連が確認された。結論:コタツを使用しない人,脱衣所を暖房する人は,住宅内の座位行動時間が短く,かつ頻繁に中断し,身体活動量も多かった。局所暖房を使用せず,非居室でも暖房を行い家を暖かく保つことは,住宅内の座位行動を抑制し身体活動を促進する可能性がある。(著者抄録)

ASSOCIATION BETWEEN FEELING COLD IN THE BEDROOM AND THE INCIDENCE OF UPPER RESPIRATORY INFECTION SYMPTOMS

Odgerel Chimed-Ochir, Yoshihisa Fujino, Yuko Mine, Toshiharu Ikaga, Tomohiro Ishimaru, Tatsuhiko Kubo

SOUTHEAST ASIAN JOURNAL OF TROPICAL MEDICINE AND PUBLIC HEALTH (SOUTHEAST ASIAN MINISTERS EDUC ORGANIZATION) 52 ( 1 ) 86 - 95 2021.02

Research paper (scientific journal), Joint Work, Accepted, ISSN 01251562

A cold ambient temperature in the house may be associated with risk of respiratory infection. In this study, we aimed to determine if there is a significant association between a perception of a cold bedroom and the presence of upper respiratory infection symptoms in order to inform efforts to reduce the incidence of upper respiratory infections in the study population. For this study, subjects were purposely selected from employees and their spouses of a single company in Kyushu, Japan. The study was conducted from December 2018 to March 2019. Each subject was asked to complete a self-administered questionnaire and which best classified how they felt at bedtime: never, sometimes or always. Each subject was also asked whether they had upper respiratory tract infection symptoms, whether they took over-the-counter medication or saw a physician for their symptoms. Between-group differences were examined for significance using the Chi square test. Logistic regression analysis was used to evaluate the potential association between the level of perceived coldness and the likelihood of having an upper respiratory tract infection and its consequences. A total of 1196 subjects were included in the study, 64% male (826 employees (89% male) and 370 spouses (8% male)). The mean age of study subjects was 44 (+/- 12) years. Of the total subjects, 44%, 44% and 12% never/rarely felt cold at bedtime, sometimes felt cold at bedtime and often/always felt cold at bedtime, respectively. Of the total subjects, 52% had upper respiratory tract infection symptoms. When compared with subjects who never/rarely felt cold, subjects who always/often felt cold had significantly greater odds of having upper respiratory tract infection symptoms (adjusted odds ratio (adjusted OR) = 2.56; 95% confidence interval (CI): 1.33-4.91; p = 0.005), having taken over-the-counter drugs for upper respiratory tract infection symptoms (adjusted OR = 1.90; 95% CI: 1.95-2.91; p = 0.003), having taken sick leave for an upper respiratory tract infection (adjusted OR = 3.54; 95% CI: 1.63-7.69; p = 0.001) and having visited a doctor for upper respiratory tract infection symptoms (adjusted OR = 3.22; 95% CI: 1.18-8.80; p = 0.022). In our study population, feeling cold in the bedroom at nighttime was significantly associated with having upper respiratory tract infection symptoms, visiting a doctor and taking sick leave. A change in the room temperature at nighttime should be considered for those who feel cold at nighttime. Further studies are needed to determine if changing the temperature of the bedroom so the person does not feel cold at nighttime will result in fewer episodes of upper respiratory tract infections or not.

Protein intake in inhabitants with regular exercise is associated with sleep quality: Results of the Shika study.

Fumihiko Suzuki, Emi Morita, Sakae Miyagi, Hiromasa Tsujiguchi, Akinori Hara, Thao Thi Thu Nguyen, Yukari Shimizu, Koichiro Hayashi, Keita Suzuki, Takayuki Kannon, Atsushi Tajima, Sumire Matsumoto, Asuka Ishihara, Daisuke Hori, Shotaro Doki, Yuichi Oi, Shinichiro Sasahara, Makoto Satoh, Ichiyo Matsuzaki, Masashi Yanagisawa, Toshiharu Ikaga, Hiroyuki Nakamura

PloS one (PUBLIC LIBRARY SCIENCE) 16 ( 2 February ) e0247926 2021.02

Research paper (scientific journal), Joint Work, Accepted, ISSN 1932-6203

STUDY OBJECTIVES: Although associations between sleep quality and environmental factors and nutrient intake have been reported, interactions between these factors have not been elucidated in detail. Therefore, this cross-sectional study examined the effects of regular exercise and nutrient intake on sleep quality using the Pittsburgh Sleep Quality Index (PSQI), which is the most frequently used index for sleep evaluation. METHODS: The participants included 378 individuals aged 40 years or older living in Shika Town, Ishikawa Prefecture. Of these individuals, 185 met the inclusion criteria. The participants completed a self-administered questionnaire assessing lifestyle habits and frequency and duration of exercise, the PSQI, and the brief-type self-administered diet history questionnaire (BDHQ) on nutrient intake. RESULTS: A two-way analysis of covariance on regular exercise and PSQI scores indicated that protein intake (17.13% of energy) was significantly higher in the regular exercise and PSQI ≤10 groups than in the non-regular exercise or PSQI ≥11 groups (p = 0.002). In a multiple logistic regression analysis with PSQI scores (≤10 and ≥11), protein intake was a significant independent variable in any of the models adjusted for confounding factors such as age, sex, body mass index, current smoker, and current drinker (OR: 1.357, 95% CI: 1.081, 1.704, p = 0.009) in the regular exercise group but not in the non-regular exercise group.Conclusions We identified a positive relationship between sleep quality and protein intake in the regular exercise group. These findings suggest that regular exercise at least twice a week for 30 minutes or longer combined with high protein intake contributes to good sleep quality.

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Heating use and sedentary behavior and physical activity at home among adults in winter: a cross-sectional analysis of the Nationwide Smart Wellness Housing Survey in Japan

Ito Maki, Ikaga Toshiharu, Oguma Yuko, Saito Yoshinobu, Fujino Yoshihisa, Ando Shintaro, Murakami Shuzo, the Smart Wellness Housing survey group

Research in Exercise Epidemiology (Japanese Association of Exercise Epidemiology) 23 ( 1 ) 45 - 56 2021

Research paper (scientific journal), Joint Work, Accepted, ISSN 1347-5827

Objective: This study examined the association between use of heating and sedentary behavior (SB) and physical activity (PA) at home among Japanese adults in winter. Methods: This cross-sectional study was conducted from November to April from 2014 to 2017. Participants (N=3,874) who intended to conduct insulation retrofitting were recruited by construction companies from 46 prefectures excluding Okinawa Prefecture and wore an accelerometer on their waist for 2 weeks. The association between heating use and log-transformed SB and PA at home was analyzed using a sex-stratified multilevel model (random-intercept model) with 3 levels; day-level variables (e.g., indoor temperature and log-transformed accelerometer wear time as an offset), nested within individual-level (e.g., age and body mass index), and nested within household-level (e.g., household income, number of housemates). The degree of association with the dependent variable was given by exponential transforming the unstandardized regression coefficient. Results: Data from 3,482 participants were analyzed. In the multilevel model, not using a kotatsu was associated with about 2% shorter SB time [men: exp(B)=0.98, p=0.022; women: exp(B)=0.98, p=0.020], an about 10% greater number of breaks in SB time [men: exp(B)=1.10, p=0.001; women: exp(B)=1.11, p<0.001], and 5-7% greater PA [men: exp(B)=1.07, p=0.005; women: exp(B)=1.05, p=0.012] than using a kotatsu. Heating the changing room was also related to shorter SB time, a greater number of breaks in SB time and greater PA in men and women. Conclusions: Not using a kotatsu and heating the changing room were associated with shorter SB and greater PA at home. Warming by heating the entire home, rather than partially heating just the living room, may decrease SB and increase PA in winter.

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STUDY ON DIFFERENT OFFICE COOLING SYSTEMS ON WORKERS BY SUBJECT EXPERIMENT (PART 1): EFFECTS OF INDOOR ENVIRONMENT DIFFERENCE DUE TO OFFICE COOLING SYSTEMS ON SKIN TEMPERATURE, PSYCHOLOGICAL QUANTITY, AND WORKPLACE PRODUCTIVITY

YANASE Tomoki, IKAGA Toshiharu, SATOU Noriaki, SHIMIZU Hiroshi, ITO Sei, KAWAKAMI Risa

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 86 ( 781 ) 205 - 214 2021

Research paper (scientific journal), Joint Work, Accepted, ISSN 1348-0685

Increasing the workplace productivity of workers has great economic value and is essential for achieving a sustainable society and economic progress. One way to increase workplace productivity is to improve the work environment, which is important because of its strong influence on workers. The work environment can be improved by using air conditioning to change the thermal environment. In Japan, radiant air-conditioning has received attention as a means to realize energy-saving buildings. However, the difference between the effects of radiant air-conditioning vs. convective air-conditioning on the human body is not clear. Therefore, in this study, we examined these effects on the physiology, psychology, and workplace productivity of workers. In February 2019, we conducted a 5-day experiment with 24 university students (12 males, 12 females). Rooms simulating office conditions were equipped with either a radiant or convection unified air-conditioning system (unified SET*, 27.2°C). In the rooms, the students simulated work such as typing, performing calculations, and creating mind maps between 9:00 and 17:00, changing rooms each day. Physiological measurements such as skin temperature were taken to evaluate stress levels, and a questionnaire was completed by the students to determine perceived comfort. Workplace productivity was evaluated based on the results of the simulated work and questionnaires. The following findings were obtained by this experiment. 1. The skin temperature difference between hands and face (hand-face) was significantly greater in convection air conditioning than in radiant air conditioning for both male and female. It was confirmed that the decrease in the skin surface temperature of the hand with respect to the face had a correlation with psychological quantities such as a decrease in thermal environment satisfaction, a decrease in air flow comfort, and an increase in subjective symptoms. 2. Thermal environment satisfaction was significantly improved in male during convection air conditioning and in female during radiant air conditioning. 3. Thermal environment satisfaction had the strongest correlation with airflow velocity. Focusing on the correlation between thermal environment satisfaction and air velocity during convection air conditioning, positive correlations were found for male and negative correlations for female, confirming different trends for male and female. 4. Focusing on airflow speed and airflow comfort, male tended to improve airflow comfort slightly when airflow speed was high, whereas female showed a marked decrease in airflow comfort when airflow speed was high. The preference for airflow was different between male and female. 5. The more comfortable the air flow was, the less fatigue was felt. 6. For female, comparing radiant air conditioning with convection air conditioning, convection air conditioning increased the rate of "yawning" subjective symptoms by 17.6% and "sleeping" by 8.3%. Other complaints regarding fatigue were also increasing, and it is considered that the unpleasant airflow led to drowsiness and fatigue. 7. Regarding work performance, we performed a multi-level logistic regression analysis with fatigue as an explanatory variable. The ratio of work scores "individual deviation value of 50 or more" is 2.0 to 2.9 times significantly higher when not feeling fatigued than when feeling fatigued in calculation, typing, mind map and all simulated work.

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Effect of housing condition on quality of life

Odgerel Chimed‐Ochir, Toshiharu Ikaga, Shintaro Ando, Tomohiro Ishimaru, Tatsuhiko Kubo, Shuzo Murakami, Yoshihisa Fujino

Indoor Air (Wiley) 31 ( 4 ) 1029 - 1037 2021

Research paper (scientific journal), Joint Work, Accepted, ISSN 09056947

This study examined the housing effect on quality of life among Japanese people. In the current cross-sectional study, we analyzed the 1-year of data (November 2015-March 2016) with 2533 participants. We used the Short Form-8 questionnaire, an 8-item instrument that measures general aspects of health-related QOL. Comprehensive Assessment System for Built Environment Efficiency housing checklist which was developed by Ministry of Land, Infrastructure, Transport and Tourism was used to assess the housing aspects. This checklist has six health elements including thermal comfort, acoustic environment, lighting environment, hygiene, safety, and security for 8 distinctive rooms/places of home. Multilevel analysis was done to identify the relationship between the perceived level of housing problem and PCS and MCS by clustering by sex. Compared to those who always felt unsafe at home due to interior design problem, participants who never felt unsafe showed an average of 10.51 (95% CI = 7.69-13.34, p < 0.0001) and 5.78 (95% CI = 2.90-8.65, p < 0.0001) higher physical and mental component score (better quality of life), respectively. Those who never had thermal, acoustic, lighting, hygiene, and security problems of housing also exhibited significantly better quality of life compared to participants who felt these problems.

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A Prospective Cohort Study of Bedroom Warming With a Heating System and Its Association With Common Infectious Diseases in Children During Winter in Japan

Fuyu Miyake, Chimed-Ochir Odgerel, Yuko Mine, Tatsuhiko Kubo, Toshiharu Ikaga, Yoshihisa Fujino

Journal of Epidemiology (Japan Epidemiological Association) 31 ( 3 ) 165 - 171 2021

Research paper (scientific journal), Joint Work, Accepted, ISSN 09175040

BACKGROUND: Customarily, bedrooms in Japan are left unheated. Although several studies have reported that the use of a heating system has positive outcomes on respiratory infection and asthma, the preventive effect of heating systems against infectious diseases in children is not well known. METHODS: We conducted a cohort study using two questionnaire surveys, one before the winter season in November, 2018 and the second after winter in March, 2019. Participants were 155 children who did not use a heating system in the bedroom and 156 children who did. RESULTS: Having a heated bedroom with a heating system was associated with decreased odds for the frequency of cold (≥3 times) (adjust odds ratio [AOR] 0.35; 95% confidence interval [CI], 0.19-0.65), duration of fever (≥3 days) (AOR 0.38; 95% CI, 0.22-0.66), duration of medicine for a cold (≥3 days) (AOR 0.91; 95% CI, 0.87-0.95), hospital visit due to cold (≥3 days) (AOR 0.54; 95% CI, 0.31-0.94), absence from school or nursery (≥3 days) (AOR 0.43; 95% CI, 0.27-0.70), influenza infection (AOR 0.43; 95% CI, 0.26-0.71), and gastroenteritis (AOR 0.39; 95% CI, 0.21-0.72). Influenza vaccination reduced the odds of influenza infection (AOR 0.36; 95% CI, 0.22-0.59) and absence from school or nursery (≥3 days) (AOR 0.62; 95% CI, 0.39-0.99). CONCLUSION: This study implies that the heating of bedrooms may have a preventive effect against infections among children. Broader dissemination of this knowledge in Japan will require cultural change through public health awareness.

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Perception of feeling cold in the bedroom and sleep quality.

Odgerel Chimed-Ochir, Shintaro Ando, Shuzo Murakami, Tatsuhiko Kubo, Tomohiro Ishimaru, Yoshihisa Fujino, Toshiharu Ikaga

Nagoya journal of medical science (NAGOYA UNIV, SCH MED) 83 ( 4 ) 705 - 714 2021

Research paper (scientific journal), Joint Work, Accepted, ISSN 00277622

Sleep disorders are drawing the attention of both medical and public health concern worldwide. In Japan, research suggests that one fifth of adults do not receive appropriate sleep and 40% of adults sleep less than 6 hours a day, and sleep rates are decreasing further year by year. Many studies show that cold indoor environments negatively affect sleep comfort and quality. Whereas these studies have focused on the effects of low bedroom temperature, few studies have focused on the effect of perception of coldness. Indoor temperature is typically much lower in Japan than in other countries. Therefore, the current study aimed to identify the effect of perception of bedroom coldness on sleep quality among Japanese adults. After controlling for covariates of age, presence of current disease and pain, smoking and consumption of alcohol (Model 1), participants who sometimes, often or always felt cold in the bedroom exhibited 0.57 (95% CI=0.32-0.83, p=<.0001), 1.08 (95% CI=0.82-1.35, p<.0001) or 2.25 (95% CI=1.83-2.67, p<.0001) higher PSQI scores compared to the group which didn't feel cold in bedroom. Our findings suggest keeping the bedroom thermal environment above a minimum limit as recommended by the World Health Organization or other organization during colder, winter nights when feeling cold during sleep. Additional deficiencies in the housing infrastructure, air quality issues due to the use of a heater, and micro bed environment need to be holistically addressed. Sleep quality can be improved by certain level via providing thermally comfortable sleeping environment.

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HIERARCHICAL STRUCTURE ANALYSIS FOR RISK FACTORS OF NEEDING LONG-TERM CARE IN THE LIVING ENVIRONMENT AS MEDIATED BY SOCIAL CAPITAL

MIYAZAKI Emiri, ANDO Shintaro, IKAGA Toshiharu

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 86 ( 782 ) 399 - 408 2021

Research paper (scientific journal), Accepted, ISSN 13480685

In Japan, healthcare and nursing care expenses for the elderly are increasing year by year, and extending healthy life expectancy is therefore desirable. Social capital (SC) is a measure of the degree of social interaction and has been gaining attention as a health-related Previous studies have shown that few people have poor subjective health in areas with good SC scores. Thus, a living environment that fosters SC might facilitate the improvement and maintenance of health status. The purpose of this study was to clarify the effects of living environment, such as facilities and community outreach efforts, on nursing care risk as mediated by SC. A questionnaire survey was carried out for 3 weeks from September to October 2018.Participants were adults in three elementary school districts in Niihama City, Ehime Prefecture, Japan Survey contents included SC, neighborhood environment, residential environment, and health status. A total of 7,220 questionnaires were distributed, and 2,693 were correctly completed (valid response rate = 37.3%) The number of samples used for analysis was 2,053.Of respondents over 65 years of age, 26.8% were at high risk of needing long-term care. Mann-Whitney U test was performed to verify the impact of SC on risk of needing long-term care. Logistic regression analysis was performed using participant attributes such as sex and household composition as moderator effects. The aim was to clarify the effects of living environment such as facilities and community outreach on the risk of needing long-term care via SC.The analysis model considered factors including age, sex, educational attainment, and length of residence in the area.The odds ratio (OR) of requiring long-term care for low SC compared with high SC was 1.91 (p <0.01). Next, I examined the relationship between SC and the living environment based on the "Facilities" and "Activity participation," or "Communication" items of living environment. The OR of SC for neighborhood environment factors ranged from 1.3 to 2.4 (p <0.05), and the OR of SC for housing environment factors ranged from 1.3 to 3.0 (p <0.05).Finally, path analysis was performed. An index for the housing and neighborhood environments was determined as the total score of the items that showed the relationships between SC and the housing and neighborhood environments, as analyzed previously. The determination coefficient for the risk of needing long-term care was 0.19.In summary, the facilities of the living environment affected SC directly or via the community items and finally affected the risk of needing long-term care. A study limitation is that the results were based solely on data that covered one target area. In the future, we plan to conduct questionnaire surveys in other regions using statistical data and to analyze responses considering regional characteristics.

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Intervention study of the effect of insulation retrofitting on home blood pressure in winter: a nationwide Smart Wellness Housing survey.

Wataru Umishio, Toshiharu Ikaga, Kazuomi Kario, Yoshihisa Fujino, Tanji Hoshi, Shintaro Ando, Masaru Suzuki, Takesumi Yoshimura, Hiroshi Yoshino, Shuzo Murakami

Journal of hypertension (Ovid Technologies (Wolters Kluwer Health)) 38 ( 12 ) 2510 - 2518 2020.12

Research paper (scientific journal), Joint Work, Accepted, ISSN 0263-6352

OBJECTIVE: The WHO's Housing and health guidelines (2018) listed 'low indoor temperatures and insulation' as one of five priority areas, and indicated insulation retrofitting to help mitigate the effect of low indoor temperatures on health. However, there is still not enough evidence for the effect of insulation retrofitting based on an objective index. METHODS: We conducted a nonrandomized controlled trial comparing home blood pressure (HBP) between insulation retrofitting (942 households and 1578 participants) and noninsulation retrofitting groups (67 households and 107 participants). HBP and indoor temperature were measured for 2 weeks before and after the intervention in winter. To examine the influence of insulation retrofitting on HBP, we used multiple linear regression analysis. RESULTS: The analyses showed that indoor temperature in the morning rose by 1.4°C after insulation retrofitting, despite a slight decrease in outdoor temperature by 0.2°C. Insulation retrofitting significantly reduced morning home SBP (HSBP) by 3.1 mmHg [95% confidence interval (95% CI): 1.5-4.6], morning home DBP (HDBP) by 2.1 mmHg (95% CI: 1.1-3.2), evening HSBP by 1.8 mmHg (95% CI: 0.2-3.4) and evening HDBP by 1.5 mmHg (95% CI: 0.4-2.6). In addition, there was a dose-response relationship between indoor temperature and HBP, indicating the effectiveness of a significant improvement in the indoor thermal environment. Furthermore, there was heterogeneity in the effect of insulation retrofitting on morning HSBP in hypertensive patients compared with normotensive occupants (-7.7 versus -2.2 mmHg, P for interaction = 0.043). CONCLUSION: Insulation retrofitting significantly reduced HBP and was more beneficial for reducing the morning HSBP of hypertensive patients.

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Disparities of indoor temperature in winter: A cross-sectional analysis of the Nationwide Smart Wellness Housing Survey in Japan.

Wataru Umishio, Toshiharu Ikaga, Yoshihisa Fujino, Shintaro Ando, Tatsuhiko Kubo, Yukie Nakajima, Tanji Hoshi, Masaru Suzuki, Kazuomi Kario, Takesumi Yoshimura, Hiroshi Yoshino, Shuzo Murakami

Indoor air (Wiley) 30 ( 6 ) 1317 - 1328 2020.11

Research paper (scientific journal), Joint Work, Accepted, ISSN 09056947

The WHO Housing and health guidelines recommend a minimum indoor temperature of 18°C to prevent cold-related diseases. In Japan, indoor temperatures appear lower than in Euro-American countries because of low insulation standards and use of partial intermittent heating. This study investigated the actual status of indoor temperatures in Japan and the common characteristics of residents who live in cold homes. We conducted a nationwide real-world survey on indoor temperature for 2 weeks in winter. Cross-sectional analyses involving 2190 houses showed that average living room, changing room, and bedroom temperatures were 16.8°C, 13.0°C, and 12.8°C, respectively. Comparison of average living room temperature between prefectures revealed a maximum difference of 6.7°C (Hokkaido: 19.8°C, Kagawa: 13.1°C). Compared to the high-income group, the odds ratio for living room temperature falling below 18°C was 1.38 (95% CI: 1.04-1.84) and 2.07 (95% CI: 1.28-3.33) for the middle- and low-income groups. The odds ratio was 1.96 (95% CI: 1.19-3.22) for single-person households, compared to households living with housemates. Furthermore, lower room temperature was correlated with local heating device use and a larger amount of clothes. These results will be useful in the development of prevention strategies for residents who live in cold homes.

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Impact of Cold Indoor Temperatures on Overactive Bladder: A Nationwide Epidemiological Study in Japan

Ishimaru T, Ando S, Umishio W, Kubo T, Murakami S, Fujino Y, Ikaga T

Urology (Urology) 145 60 - 65 2020.11

Research paper (scientific journal), Joint Work, ISSN 00904295

© 2020 Elsevier Inc. OBJECTIVE: To assess the relationship between overactive bladder (OAB) and indoor temperatures in the living room and bedroom. METHODS: Questionnaire data and indoor temperature measurements were obtained from a baseline survey collected during the winter months from November 2014 to March 2019. We performed multiple logistic regression to assess the relationships between OAB and indoor temperatures in the living room and bedroom. RESULTS: The prevalence of overactive bladder was 16.4% among 4782 participants living in 2453 dwellings. The odds of having OAB were higher for participants whose average living room temperature at bedtime was lower than 12°C than for those whose average bedtime living room temperature was at least 18°C (adjusted odds ratio = 1.44, 95% confidence interval: 1.03-2.00). No association was observed between bedroom temperature and OAB. CONCLUSION: These results suggest that thermal comfort in the living room—but not in the bedroom—may improve OAB symptoms. Additionally, using sufficient bedding may prevent cold bedrooms from having a negative impact in terms of OAB. Future studies should focus on housing interventions and education regarding lifestyle modification in patients with OAB.

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ECO-EFFICIENCY ASSESSMENT BY INDUSTRY FOR JAPANESE MUNICIPALITIES NATIONWIDE BASED ON GROSS REGIONAL PRODUCT AND ENVIRONMENTAL DAMAGE

YAMASAKI Junya, IKAGA Toshiharu, ITSUBO Norihiro

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 85 ( 776 ) 745 - 755 2020.10

Research paper (scientific journal), Joint Work, ISSN 13480685

In the environmental accounting of local governments in Japan, it is considered important to introduce the concept of eco-efficiency into the assessment of each industry and administrative division. Therefore, in this study, eco-efficiency assessment by industry was conducted uniformly for all Japanese municipalities based on two indicators: economic value and environmental load. For these, the respective indicators were gross regional product (GRP) and amount of environmental damage, as defined in a previous study. That study quantified annual environmental loads in Japanese municipalities within the framework of the endpoint-type life cycle impact assessment method "LIME2 (Life-Cycle Impact Assessment Method Based on Endpoint Modeling 2)". In this method, assessment results are calculated in monetary units called the "Eco-index Yen" (unit: Japanese yen) and environmental loads of several impact categories are integrated, such as "global warming" and "land use, " based on environmental conditions and knowledge unique to Japan. Another indicator, eco-efficiency, was defined as a division of monetary units (GRP divided by amount of environmental damage), as calculated for wide regions and individual municipalities in Japan in order to discuss their situation from the perspective of economics and the environment. Based on reliable, verifiable, and comparable statistical information, each index value was calculated for all industries throughout Japan in 2015: GRP was 2.28 million yen/capita, environmental damage was 32.6 thousand yen/capita, and eco-efficiency was 69.8. The assessment results of all municipalities were placed on a map to visualize the regionality of eco-efficiency, which revealed industry trends nationwide. For example, the eco-efficiency of "manufacturing" showed a trend that reflected the major local products in each area. The eco-efficiency value tended to be higher in areas that had active automobile and electronic component industries because these products produced relatively large benefits compared with their environmental loads. Next, the study focused on 21 large municipalities, including government-designated cities, located in representative urban areas in Japan. The results showed that the eco-efficiency of many industries in most of the 21 municipalities exceeded the national average. This suggests that the eco-efficiency of each industry tends to be higher in more densely populated cities in Japan. This hypothesis is potentially important for discussing "centralization of city functions" from the perspective of industry structure. Verification of this hypothesis will be investigated in the future. Taken together, these results indicate that it has become possible to quantify the real situation of each industry throughout Japan for both individual municipalities and regions. No studies to date have quantified the eco-efficiency of each industry in all Japanese municipalities monetarily and uniformly—this study is the first to provide an example from each industry throughout Japan in the field of environmental science.

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Comprehensive fungal community analysis of house dust using next-generation sequencing

Izawa K, Kubosaki A, Kobayashi N, Akiyama Y, Yamazaki A, Hashimoto K, Konuma R, Kamata Y, Hara-Kudo Y, Hasegawa K, Ikaga T, Watanabe M

International Journal of Environmental Research and Public Health (International Journal of Environmental Research and Public Health) 17 ( 16 ) 1 - 11 2020.08

Research paper (scientific journal), Joint Work, ISSN 16617827

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. Fungal community analyses in homes have been attracting attention because fungi are now generally considered to be allergens. Currently, these analyses are generally conducted using the culture method, although fungal communities in households often contain species that are difficult to culture. In contrast, next-generation sequencing (NGS) represents a comprehensive, labor-and time-saving approach that can facilitate species identification. However, the reliability of the NGS method has not been compared to that of the culture method. In this study, in an attempt to demonstrate the reliability of this application, we used the NGS method to target the internal transcribed spacer 1 (ITS1) in the fungal genome, conducted fungal community analyses for 18 house-dust samples and analyzed fungal community structures. The NGS method positively correlated with the culture method regarding the relative abundance of Aspergillus, Penicillium, Cladosporium and yeasts, which represent the major fungal components found in houses. Furthermore, several genera, such as Malassezia, could be sensitively detected. Our results imply that the reliability of the NGS method is comparable to that of the culture method and indicates that easily available databases may require modifications, including the removal of registrations that have not been sufficiently classified at the genus level.

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Development of an environmentally friendly PV/T solar panel

Terashima K, Sato H, Ikaga T

Solar Energy (Solar Energy) 199 510 - 520 2020.03

Research paper (scientific journal), Joint Work, ISSN 0038092X

© 2020 The Authors A possibility of developing an environmental-friendly photovoltaic/thermal (PV/T) solar panel, which can shut high temperature radiation within a panel box, was experimentally confirmed. The panel has a decompression-boiling heat collector, which can absorb heat from the PV module and can keep the air and the cover glass inside the panel box at lower temperature by using lower boiling temperature of working fluid under vacuum condition. The panel also has an emboss-processed cover glass, which can totally reflect the high temperature heat radiation from the PV module within the panel box. The experimental results using a single PV/T system showed that it could keep the heat radiation temperature from the PV/T solar panel surface around 45 °C even in summer; it provided the hot water at least 60 °C by controlling the flow-rate; and it produced 71.3% of solar energy in total as electricity and 40 °C heat, in summer, Yokohama, Japan. Highly efficient utilization of solar energy with small environmental heat-load would be possible by using the proposed PV/T system.

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DEVELOPMENT OF WORK ENVIRONMENT SUBJECTIVE ASSESSMENT TOOL FOR IMPROVEMENT OF WORKERS' WORK EFFICIENCY AND HEALTH PROMOTION

ABE Yuko, SHIRAISHI Yasuyuki, HAYASHI Tatsuya, IKAGA Toshiharu, ANDO Shintaro

AIJ Journal of Technology and Design (Architectural Institute of Japan) 26 ( 62 ) 191 - 196 2020.02

Research paper (scientific journal), Joint Work, ISSN 13419463

In recent years, not only the residence but also the effort of health promotion by improving the social environment including the working and the regional environment has attracted attention. This paper introduces a subjective assessment tool of the work environment, referred to as "CASBEE- Office Health Checklist". This tool is an assessment tool for workers themselves to evaluate satisfaction for office environment where workers spend a lot of time. By using this tool, people are aware of factors that affect health and intellectual productivity, and it is expected that they can conduct health management strategically, which leads to environmental improvement.

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Annual Nationwide Environmental Impact Assessment of Japanese Municipalities by Type of Business within the Endpoint-type LCIA Method "lIME2"

Yamasaki J, Ikaga T, Itsubo N

IOP Conference Series: Earth and Environmental Science (IOP Conference Series: Earth and Environmental Science) 410 ( 1 ) 012067 - 012067 2020.01

Research paper (scientific journal), Joint Work, ISSN 17551307

© 2020 Published under licence by IOP Publishing Ltd. This study attempts a comprehensive environmental impact assessment, within the context of annual operations by type of business in each division of Japanese municipality, based on the LCIA (Life Cycle Impact Assessment) method. LIME2 (Life-Cycle Impact Assessment Method Based on Endpoint Modeling 2) is an example of an endpoint-type LCIA method developed in Japan. Annual environmental impacts of municipalities nationwide are assessed by LIME2 from the perspective of environmental damage, indexed to the Japanese yen. Here, this index is referred to as the "Eco-index Yen". The availability of necessary inventory data in each category is surveyed from statistical information published by governments. From the assessment results based on these conditions, the annual damage amount of all Japanese municipalities taken together is 4.63 trillion yen. The assessment result of each municipality is converted into indicators per capita and per GRP (Gross Regional Product). These results are displayed on a map of Japan to visualize regional characteristics nationwide by type of business, across different types of industries, including the residential and transportation sectors. As described in this study, these results provide a first step toward constructing a new methodology for comprehensive environmental impact assessment of administrative units.

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ANNUAL ENVIRONMENTAL IMPACT ASSESSMENT OF ADMINISTRATIVE DIVISIONS IN 42 COUNTRIES WITHIN THE FRAMEWORK OF GLOBAL-SCALE LCIA METHOD "LIME3"

YAMASAKI Junya, IKAGA Toshiharu, ITSUBO Norihiro

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 85 ( 767 ) 67 - 77 2020

Research paper (scientific journal), Joint Work, Accepted, ISSN 13480685

A global standard method for measuring environmental loads in administrative divisions has not been officially established for environmental accounting at the local government level. As a consequence, environmental accounting has not been adopted by local governments as widely as private companies around the world. Life cycle impact assessment (LCIA) is one aspect of research in the field of life-cycle assessment, whereby environmental loads throughout the life cycle of products and services are measured in a quantitative way. Research in which environmental loads are determined according to geographical location has become more and more important. This study therefore focused on administrative divisions in 42 countries, most of which are OECD members, and attempted to quantify the annual environmental loads emitted within each division in the year 2015, using the global-scale LCIA method. For this, this study leveraged the assessment theory Life-Cycle Impact Assessment Method Based on Endpoint Modeling 3 (LIME3). This method is able to calculate assessment results in monetary units while integrating the environmental loads of several impact categories, such as climate change and land use, based on environmental conditions and environmental science. Using statistical information that was reliable, verifiable, and comparable, this study calculated environmental loads in administrative divisions in 42 countries. The total environmental damage amount for the 42 countries was calculated to be 5.22 trillion USD. The top five amounts were land use (1.76 trillion USD), water consumption (1.36 trillion USD), forest resource consumption (0.70 trillion USD), climate change (0.52 trillion USD), and fossil fuel consumption (0.50 trillion USD). When the damage amounts were divided by the area or population of each division, the average amount per unit area for all Territorial level 2 (TL2) regions was calculated to be 67,300 USD/km2 (area-weighted average), and the average of amount per capita was calculated 1,250 USD/capita (population-weighted average). These damage amounts per unit area and per capita were placed on a world map according to impact category to visualize the regionality of environmental loads worldwide. The amount per unit area for most categories showed a trend similar to population distribution around the world, and the values for land use also showed a trend indicative of local agricultural activity in some countries. In particular, the amount per capita for climate change as well as the total of all categories showed a contrasting trend to the amount per unit area, and the value tended to be relatively lower in densely populated areas around the world. The variation coefficient for the damage amounts per unit area and per capita was calculated for each region in order to statistically capture the disparities of environmental loads according to impact category. The disparities of environmental loads that were deeply related to housing, such as climate change and waste, tended to be narrow among TL2 regions worldwide. From these results, this study revealed environmental impacts around the world from the perspective of several categories, thus providing information useful for making decisions about international environmental policies.

PERCEIVED INDOOR TEMPERATURE AND CHANGE IN NURSING CARE LEVEL IN COMMUNITY-DWELLING ELDERLY:A field survey on the effect of winter indoor thermal environment on care requirements: Part 3

ONO Mari, IKAGA Toshiharu, NAKAJIMA Yukie, HOSHI Tanji

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 85 ( 769 ) 197 - 204 2020

Research paper (scientific journal), Joint Work, ISSN 13480685

The number of people needing nursing care more than doubled from 2000 to 2014, and medical expenses tend to increase yearly, in part because of the high demand for in-home care. Because elderly spend most of their time at home, the indoor thermal environment of their houses is important. The objective of this study was to investigate the relationship between perceived indoor temperature and the change in required care level among the elderly. Participants were 126 community-dwelling elderly aged 65 years or older using rehabilitation facilities in Osaka, Kochi, and Yamanashi Prefectures in Japan. A standardised questionnaire survey and indoor temperature measurements were conducted in winter to assess housing characteristics. Nursing care records from rehabilitation facilities were collected by photographing them with a camera. Spearman's rank test was conducted to assess the correlations between perceived indoor temperature, as indicated in responses to the questionnaire survey, and room temperatures measured in the living room, bedroom, and dressing room of participants. The total score from the CASBEE health checklist had the highest correlation coefficient. Participants were divided into a cold group and a warm group according to their total scores of perceived indoor temperature. The average perceived room temperature in the living room, bedroom, and dressing room was significantly lower in the cold group than in the warm group. When we compared the nursing care level in the latest survey with that from one year earlier, we found no change in most participants. The chi-square test was used to analyse the relation between perceived indoor temperature and change in required care level. We found that participants in the cold group were more likely to need a higher nursing care level than those in the warm group, at the 1% level of significance (p<0.01) Multiple logistic regression analysis was conducted by using change in care level as an objective variable. Perceived indoor temperature was significant at the 5% level of significance, and the adjusted odds ratio was 2.84 (95% CI: 1.16−6.98, p<0.05). This can be interpreted as meaning that the likelihood of the change in nursing care level from "same or lower" to "higher" was 2.84 times greater when the perceived indoor temperature changed from "warm" to "cold", indicating a high risk in the cold group that their level of nursing care would increase. The results suggest that maintaining a warm room temperature in winter helps to prevent an increase in the required nursing care level in community-dwelling elderly.

A NEW PROPOSAL FOR ENVIRONMENTAL ACCOUNTING OF JAPANESE MUNICIPALITY WITH THE FRAMEWORK OF ENDPOINT-TYPE LCIA METHOD "LIME2":Calculation of Environmental Conservation Effects in Yokohama City from 2000 to 2015

YAMASAKI Junya, IKAGA Toshiharu, ITSUBO Norihiro

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 85 ( 769 ) 225 - 235 2020

Research paper (scientific journal), Joint Work, ISSN 13480685

In recent years, Japanese businesses have been increasingly adopting the practice of environmental accounting, which is the reporting of the firm's environmental impacts in monetary terms. However, whereas private companies can make use of the Environmental Accounting Guidelines 2005 published by the Ministry of the Environment, no official environmental accounting guidelines have been provided by the government of Japan for public agencies, such as local governments. Thus, this study focused on Japanese municipalities, and proposed a unified methodology based on the endpoint-type LCIA method LIME2 (Life-Cycle Impact Assessment Method Based on Endpoint Modeling 2) for calculating the effects of environmental conservation, which is one item used by administrative divisions in Japan for environmental accounting. In a previous study, we conducted an annual environmental impact assessment of Japanese municipalities nationwide within the framework of LIME2. This study integrates the knowledge gained from that study with the basic tenets of the Environmental Accounting Guidelines 2005, and furthermore contributes unique ideas on interpreting the assessment results. The Environmental Accounting Guidelines 2005 state that the effects of environmental conservation should be calculated by subtracting the environmental load of base period from the environmental load of the current period. Accordingly, in this study the environmental conservation effect of a given administrative division was determined by taking the difference in the environmental impact assessment results of that municipality between two different years. In addition, two principles were proposed for assessing the location of environmental loads related to administrative divisions: territorial occurrence and territorial benefit. This study furthermore proposed that environmental loads from all Japanese municipalities expressed in monetary terms in accordance with LIME2 shall be called the "damage amount on environmental assets," and that local governments should take responsibility for reducing their damage amounts evenly. The assessment indicators for calculating environmental load were tentatively selected based on the inventories provided by LIME2 as well as the availability of statistical information at the municipal level. When the methodology was applied to the city of Yokohama, the total damage amounts for the years 2000, 2005, 2010, and 2015 were calculated as 96.1, 99.6, 97.6, and 97.2 billion yen, respectively, with the total environmental conservation effect over 15 years calculated as -1.07 billion yen. Because some LIME2 assessment categories are related to certain Sustainable Development Goals (SDGs) set by the United Nations—including Goal 3 (Good Health and Well-Being), Goal 9 (Industry, Innovation and Infrastructure), Goal 12 (Responsible Consumption and Production), Goal 13 (Climate Action), and Goal 15 (Life On Land)—this study attempted to apply the assessment results of Yokohama to the framework of the SDGs. The results showed that the damage amounts related to Goals 9 and 15 decreased by 4.51 and 0.862 billion yen, respectively, and the damage amounts related to Goals 3, 12, and 13 increased by 5.58, 0.889, and 8.75 billion yen, respectively, over 15 years. These results indicate that the actual environmental loads of certain administrative divisions in Japan can be expressed in monetary terms, thereby providing primary knowledge necessary for developing standardized environmental accounting guidelines for Japanese municipalities.

ANNUAL NATIONWIDE ENVIRONMENTAL IMPACT ASSESSMENT OF JAPANESE MUNICIPALITIES WITHIN THE FRAMEWORK OF ENDPOINT-TYPE LCIA METHOD "LIME2" (PART 2): VISUALIZATION OF TEMPORAL CHANGES

YAMASAKI Junya, IKAGA Toshiharu, ITSUBO Norihiro

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 85 ( 77 ) 523 - 533 2020

Research paper (scientific journal), Joint Work, ISSN 13480685

In Japan, a unified system for measuring environmental loads in administrative areas has not been officially established. In a previous study, the authors focused on Japanese minimum administrative divisions (municipalities) and quantified the annual environmental loads attributable to each division in the year 2015 using the LCIA method. For this, the study leveraged the assessment theory of the Life-Cycle Impact Assessment Method Based on Endpoint Modeling 2 (LIME2). This method is able to calculate assessment results in monetary units via the so-called "Eco-index Yen" (unit: Japanese yen) while integrating the environmental loads of several impact categories, such as "Climate change" and "Land use". Based on this, the present study sought to conduct the same assessment for each year from 2000 to 2015, and visualize the temporal changes in environmental loads within all Japanese municipalities by impact categories and by type of business. Using statistical information that was reliable, verifiable, and comparable, the total environmental damage amount for the whole of Japan was calculated to be 8.40, 8.47, 7.50, and 7.41 trillion yen in 2000, 2005, 2010, and 2015, respectively. This indicates that damage amounts were generally on a downward trend throughout the 16-year period. Focusing on impact categories, the damage amounts for five categories, "Photochemical ozone, " "Resources consumption, " "Acidification, " "Atmosphere pollution, " and "Waste (domestic), " decreased every five-year period. Focusing on the type of business, the damage amounts for "Primary Industries (Agriculture, etc.)" and "Secondary Industries (Manufacturing, etc.)" decreased every five-year period, and the damage amount for "Tertiary Industries (Service industry, etc.)" began to decline in 2005. This suggests that damage amounts reflect the effects of environmental policies and the activities of industries over time around the country. Next, the temporal changes in damage amounts were placed on a map of Japan to visualize patterns across municipalities. In overall terms, declining damage was discerned across many municipalities between 2005 and 2010. This tendency was particularly pronounced in the "Climate change" and "Atmosphere pollution" impact categories and the "Construction" and "Manufacturing" industries. This likely reflects not only local environmental policy interventions, but also the global financial crisis that began in 2008. From these results, it became possible to visualize the change over time in environmental loads based on social factors related to each period in Japan. This study provides information that can be used for making decisions about environmental policies, as well as primary knowledge needed to develop standardized environmental accounting guidelines for Japanese municipalities.

Verification of Work Environment Subjective Assessment Tool for Improving Work Efficiency and Health Promotion

ABE Yuko, SHIRAISHI Yasuyuki, HAYASHI Tatsuya, IKAGA Toshiharu, ANDO Shintaro, FUJINO Yoshihisa

Transactions of the Society of Heating,Air-conditioning and Sanitary Engineers of Japan (The Society of Heating, Air-Conditioning & Sanitary Engineers of Japan) 45 ( 278 ) 27 - 35 2020

Research paper (scientific journal), Joint Work, Accepted, ISSN 0385-275X

In recent years, along with the residence, the efforts toward health promotion by improving the social environments, including the working and regional environments, have attracted considerable attention. Owing to the significant amount of time spend by office workers in the workplace, the ideal modification of their working environment and work habits could potentially improve their intellectual productivity and physical health. However, to the best of our knowledge, the optimal environmental improvements have not yet been identified. Therefore, we developed CASBEE-OHC, an objective workplace evaluation tool. To verify the effectiveness of the revised CASBEE-OHC, we conducted a WEB questionnaire regarding the health and psychological status of workers in addition to their general environment. First, the relationship between the degree of dysfunction in labor and the environments (working environment, residence, and community) in which the office workers stay was analyzed. Next, the influence of the confounding factors were examined via multiple regression analysis on the subjective work efficiency and logistic regression analysis on the degree of dysfunction in labor. The following results were obtained; 1) The correlation analysis results stated that the degree of dysfunction in labor and work efficiency of workers are influenced by both the work environment and their general environment, such as residences and communities. Additionally, the health status was found to be signficantly affected by the residential environments. Furthermore, a high CASBEE-OHC score (better office environment) indicated a lower WFun score (i.e., the degree of dysfunction in labor), thereby implying higher subjective work efficiency. 2) Based on multiple regression analysis, it was confirmed that the working environment and age of workers, influenced the work efficiency. The results of logistic regression analysis suggested that the risk of high degree of labor impairment increased when the surrounding environment, including the office space, was bad. Furthermore, regarding the WFun and Pittsburgh scores, the AOR comparison between models suggested that the residential environments mildly affect labor dysfunction, while the office environments have a significant impact at higher altitudes. Thus, the importance of the maintenance of other surrounding environments was demonstrated.

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Verification of Work Environment Subjective Assessment Tool for Improving Work Efficiency and Health Promotion

ABE Yuko, SHIRAISHI Yasuyuki, HAYASHI Tatsuya, IKAGA Toshiharu, ANDO Shintaro, FUJINO Yoshihisa

Transactions of the Society of Heating,Air-conditioning and Sanitary Engineers of Japan (The Society of Heating, Air-Conditioning & Sanitary Engineers of Japan) 45 ( 278 ) 27 - 35 2020

Research paper (scientific journal), Accepted, ISSN 0385-275X

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Heatstroke management during the COVID-19 epidemic: recommendations from the experts in Japan

Yokobori Shoji, Kanda Jun, Okada Yohei, Okano Yuichi, Kaneko Hitoshi, Kobayashi Tatsuho, Kondo Yutaka, Shimazaki Junya, Takauji Shuhei, Hayashida Kei, Hifumi Toru, Fujita Motoki, Moriya Takashi, Yagi Masaharu, Yamaguchi Junko, Oda Yasutaka, Shiraishi Shinichiro, Wakasugi Masahiro, Shimizu Keiki, Miyake Yasufumi, Yokota Hiroyuki, Yaguchi Arino, Shimazu Takeshi, Asami Masahiro, Hamaguchi Jun, Ishihara Tadashi, Kawagishi Toshiomi, Igarashi Yutaka, Hirano Yohei, Nakae Ryuta, Arakawa Yuki, Miyamoto S

ACUTE MEDICINE & SURGERY (WILEY) 7 ( 1 ) 2020

Research paper (scientific journal), Joint Work, Accepted, ISSN 2052-8817

Fever and hyperthermia are the main symptoms of coronavirus disease (COVID-19) and heatstroke, and it is difficult to distinguish them. There is a need to discuss safe prevention and medical treatment for heatstroke. In view of the above issues, the Japanese Association for Acute Medicine "Committee on heatstroke and hypothermia" established a "Working group on heatstroke medical care given the COVID-19 epidemic" jointly with the Japanese Society for Emergency Medicine that focuses on emergency medical personnel, including paramedics and nurses, the Japanese Association for Infectious Diseases, an academic society of infectious disease, and the Japanese Respiratory Society, an academic organization on respiratory diseases. The precautions for prevention of heatstroke this summer during the coronavirus epidemic was summarized in "Proposals on heatstroke prevention based on the COVID-19 epidemic" as follows and was issued on 1 June, 2020. Based on the above, we have determined that guidance in clinical practice is necessary not only from the viewpoint of heatstroke prevention, but also medical treatment. As such, we have created this guidance in the form of supplementary recommendations.

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Cross-Sectional Analysis of the Relationship Between Home Blood Pressure and Indoor Temperature in Winter: A Nationwide Smart Wellness Housing Survey in Japan.

Wataru Umishio, Toshiharu Ikaga, Kazuomi Kario, Yoshihisa Fujino, Tanji Hoshi, Shintaro Ando, Masaru Suzuki, Takesumi Yoshimura, Hiroshi Yoshino, Shuzo Murakami

Hypertension (Dallas, Tex. : 1979) (Hypertension (Dallas, Tex. : 1979)) 74 ( 4 ) 756 - 766 2019.10

Research paper (scientific journal), Joint Work, ISSN 0194911X

Mortality due to cardiovascular disease rises sharply in winter. Known as excess winter mortality, this phenomenon is partially explained by cold exposure-induced high blood pressure. Home blood pressure, especially in the morning, is closely associated with cardiovascular disease risk. We conducted the first large nationwide survey on home blood pressure and indoor temperature in 3775 participants (2095 households) who intended to conduct insulation retrofitting and were recruited by construction companies. Home blood pressure was measured twice in the morning and evening for 2 weeks. The relationship between home blood pressure and indoor temperature in winter was analyzed using a multilevel model with 3 levels: repeatedly measured day-level variables (eg, indoor ambient temperature and quality of sleep), nested within individual-level (eg, age and sex), and nested within household level. Cross-sectional analyses involving about 2900 participants (1840 households) showed that systolic blood pressure in the morning had significantly higher sensitivity to changes in indoor temperature (8.2 mm Hg increase/10°C decrease) than that in the evening (6.5 mm Hg increase/10°C decrease) in participants aged 57 years (mean age in this survey). We also found a nonlinear relationship between morning systolic blood pressure and indoor temperature, suggesting that the effect of indoor temperature on blood pressure varied depending on room temperature range. Interaction terms between age/women and indoor temperature were significant, indicating that systolic blood pressure in older residents and women was vulnerable to indoor temperature change. We expect that these results will be useful in determining optimum home temperature recommendations for men and women of each age group. Clinical Trial Registration- URL: http://www.umin.ac.jp/ctr/index.htm. Unique identifier: UMIN000030601.

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Analysis of the Influence of Lung Function Decline on Brain Function using Brain Healthcare Quotient

Watanabe H, Fukunaga K, Ikaga T, Mitsukura Y

IECON Proceedings (Industrial Electronics Conference) (IECON Proceedings (Industrial Electronics Conference)) 2019-October 5353 - 5357 2019.10

Research paper (scientific journal), Joint Work, ISSN 9781728148786

© 2019 IEEE. In this paper, we used Brain Healthcare Quotient (BHQ) to analyze the influence of lung function on brain function. A large-scale survey was conducted for the purpose. In the measurement survey, magnetic resonance images were acquired, and BHQ was calculated and used as brain function. As lung function, we measured forced vital capacity (FVC) and calculated forced expiratory volume 1.0 sec (FEV1.0%). As a result of analysis, it became clear that the decrease in FEV1.0% affects GM BHQ and that the decrease in lung function also affects brain function by using BHQ.

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Eco-efficiency assessment of Japanese municipalities based on environmental impacts and gross regional product

Yamasaki J, Ikaga T, Itsubo N

Sustainability (Switzerland) (Sustainability (Switzerland)) 11 ( 15 ) 4045 - 4045 2019.08

Research paper (scientific journal), Joint Work, ISSN 20711050

© 2019 by the authors. Governments at different levels need to appreciate the environmental impacts of socioeconomic activities within their boundaries. They also need to decide relevant environmental policies after carefully examining future pathways based on the relationship between the environment and the economy. This study focuses on Japanese basic administrative divisions (i.e., municipalities) and attempts to quantify the annual environmental efficiency of processes and socioeconomic activities within each of these divisions using life-cycle impact assessment (LCIA) concepts. A key element of the LCIA is the integration of different environmental loads across various impact categories, such as global warming, air pollution, and land use, and their representation through a simple indicator. First, we conduct annual environmental impact assessments for all Japanese municipalities based on reliable, verifiable, and comparable statistical information. Next, we estimate the environmental efficiency of socioeconomic activities within each division by dividing the gross regional product (GRP) with the environmental damage amounts calculated through LIME2, an LCIA-based tool tailored for Japan. Assessment results for each municipality are visualized on maps of Japan in order to highlight the spatial distribution of the values for each indicator. The findings of this study can aid local, regional, and national governments in Japan to inform environmental policy design and decision-making at different spatial levels.

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Relationship between perceived indoor temperature and self-reported risk for frailty among community-dwelling older people

Nakajima Y, Schmidt S, Fänge A, Ono M, Ikaga T

International Journal of Environmental Research and Public Health (International Journal of Environmental Research and Public Health) 16 ( 4 ) 613 - 613 2019.02

Research paper (scientific journal), Joint Work, ISSN 16617827

© 2019 by the authors. Licensee MDPI, Basel, Switzerland. This study investigated the relationship between perceived indoor temperature in winter and frailty among community-dwelling older people. This cross-sectional study included 342 people 65 years and older in Japan. Participants answered questions about demographics, frailty, housing, and perceived indoor temperature in winter. Participants were grouped based on perceived indoor temperature (Cold or Warm) and economic satisfaction (Unsatisfied or Satisfied). Differences in the frailty index between perceived indoor temperature groups and economic satisfaction groups were tested by using ANCOVA and MANCOVA. An interaction effect showed that people in the Cold Group and unsatisfied with their economic status had significantly higher frailty index scores (F(1, 336) = 5.95, p = 0.015). Furthermore, the frailty index subscale of fall risk was the specific indicator of frailty that accounted for this significant relationship. While previous research has shown the risks related to cold indoor temperature in homes, interestingly among those who reported cold homes, only those who were not satisfied with their economic situation reported being at increased risk for frailty. This highlights the potential importance of preventing fuel poverty to prevent frailty.

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Are cold extremities an issue in women’s health? Eepidemiological evaluation of cold extremities among Japanese women

Tsuboi S, Mine T, Tomioka Y, Sshiraishi S, Fukushima F, Ikaga T

International Journal of Women's Health (International Journal of Women's Health) 11 31 - 39 2019

Research paper (scientific journal), Joint Work, ISSN 1179-1411

© 2019 Tsuboi et al. Background: Unlike traditional East Asian medicine, the necessity of health care services for cold extremities is yet to be acknowledged in Western medicine. In this study, we aimed to conduct an epidemiological evaluation of this unremarkable symptom among women in Japan. Materials and methods: A cross-sectional study was conducted from February 2016 to April 2017, and data of 238 women throughout Japan were analyzed. Questionnaires were used to examine participants’ demographics, health-related behaviors, health status, and frequency of subjective symptoms over the past 1 year. The association between cold extremities and other subjective symptoms was examined by the multiple logistic regression analysis. Results: The prevalences of mild and severe cold extremities were 49.6% and 35.3%, respectively. Temperature and utilization of health care services were not significantly different by the severity of cold extremities. The accompanying symptoms that were significantly associated with the cold extremities were shoulder stiffness, fatigue, low back pain, headache, nasal congestion, itching, injury, and difficulty hearing. After multiple logistic regression analysis, low back pain (OR: 4.91) and difficulty hearing (OR: 4.84) kept the significance. Factors related to cold extremities including mental quality of life, sleep quality, and habitual drinking were significantly associated with other accompanying symptoms. Conclusion: Women with cold extremities have various accompanying symptoms and health-risk behaviors. Symptomatic treatment for cold extremities may not be sufficient, and comprehensive care would be required.

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Incidence and characteristics of bath-related accidents

Suzuki M, Shimbo T, Ikaga T, Hori S

Internal Medicine (Internal Medicine) 58 ( 1 ) 53 - 62 2019

Research paper (scientific journal), Joint Work, ISSN 09182918

© 2019 The Japanese Society of Internal Medicine. Objective Bath-related sudden cardiac arrests frequently occur in Japan. This study aimed to describe the actual incidence and characteristics of bath-related accidents, including non-fatal events, and to establish the etiology of bath-related sudden cardiac arrest. Methods This prospective cross-sectional observational study was conducted in Tokyo Metropolis and Saga and Yamagata Prefectures between October 2012 and March 2013. Emergency personnel enrolled events in this study when they recognized that activation of the emergency medical system was related to bathing. Surveillance cards were delivered and collected from the emergency personnel and attending physicians. Results In total, 4,593 events were enrolled (1,528 cardiac arrests, 935 survivors in need of help, 1,553 patients with acute illnesses, and 577 patients with injuries) in this study. In the group of survivors in need of help and with acute illness, consciousness disturbance and lethargy without any organic disease were recognized as the main symptoms. Acute coronary syndrome and stroke were infrequently diagnosed. Of the survivors, 30% had a body temperature above 38°C. Their consciousness level significantly correlated with their body temperature. Emergency personnel reported that 79% of sudden cardiac arrests were from victims whose faces were submerged in the tub water, while 18% of survivors had their faces submerged in the tub water. Conclusion This study revealed that accidents, including non-lethal events, frequently occur. The key symptoms were consciousness disturbance and lethargy characterized as a functional disorder and accompanied by an elevated body temperature. Those findings suggest that heat illness during hot water immersion causes drowning.

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ANNUAL NATIONWIDE ENVIRONMENTAL IMPACT ASSESSMENT OF JAPANESE MUNICIPALITIES WITHIN THE FRAMEWORK OF ENDPOINT-TYPE LCIA METHOD "LIME2"

YAMASAKI Junya, IKAGA Toshiharu, ITSUBO Norihiro

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 84 ( 764 ) 955 - 965 2019

Research paper (scientific journal), Joint Work, Accepted, ISSN 13480685

In Japan, a unified system to measure environmental loads in administrative areas has not been officially established for environmental accounting at the local government level. As a consequence, environmental accounting has not been adopted by local governments as widely as private companies. Life cycle impact assessment (LCIA) is one aspect of research in the field of life-cycle assessment, whereby environmental loads throughout the life cycle of products and services are measured in a quantitative way. Research in which environmental loads are determined according to geographic location has become more and more important. This study therefore focused on Japanese minimum administrative divisions (municipalities) and attempted to quantify the annual environmental loads emitted within each division in the year 2015 using the LCIA method. For this, this study leveraged the assessment theory Life-Cycle Impact Assessment Method Based on Endpoint Modeling 2 (LIME2). This method is able to calculate assessment results in monetary units called the "Eco-index Yen" (unit: Japanese yen) while integrating the environmental loads of several impact categories, such as "Global warming" and "Land use", based on environmental conditions and knowledge unique to Japan. Using statistical information that was reliable, verifiable, and comparable, the environmental damage amount for the whole of Japan was calculated to be 8.53 trillion yen. The top five amounts were "Global warming" (2.82 trillion yen), "Land use" (2.33 trillion yen), "Waste (domestic)" (1.24 trillion yen), "Biological toxicity" (0.63 trillion yen), and "Atmospheric pollution" (0.61 trillion yen). When the damage amounts were divided by the population of each municipality, the average amount per capita for all Japanese municipalities was calculated to be 67,100 yen per capita (population-weighted average). These damage amounts per capita were placed on a map of Japan according to type of impact category and type of business to visualize the regionality of environmental loads nationwide. The values for "Global warming" and "Land use" tended to be lower in the central parts of large urban areas, and the values for "Global warming" and "Atmospheric pollution" tended to be higher in areas where industries are concentrated. The values for "Primary industries" (which include agriculture) as well as "Manufacturing" were particularly indicative of local industrial activity. Tendencies related to population distribution and industrial activity were easy to see from the map. Next, standard deviation and variation coefficient for the damage amounts per capita were calculated for each region in order to statistically capture the disparities of environmental loads according to impact category and type of business. The disparities of environmental loads that were deeply related to housing, such as "Waste (domestic)" and "Land use", tended to be narrow among municipalities whereas disparities for "Manufacturing" were particularly wide because manufacturers are concentrated in certain parts of the country. From these results, this study revealed Japanese environmental impacts from the perspective of several categories, thus providing information useful for making decisions about environmental policies.

MULTIVARIATE ANALYSIS OF PERCEIVED INDOOR TEMPERATURE AND AGE AT NEED FOR LONG-TERM CARE INSURANCE:A field survey on the effect of winter indoor thermal environment on care requirements: Part 2

NAKAJIMA Yukie, IKAGA Toshiharu, ONO Mari, HOSHI Tanji, ANDO Shintaro

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 84 ( 763 ) 795 - 803 2019

Research paper (scientific journal), Joint Work, ISSN 13480685

Given the rapid ageing of the Japanese population, it is important to identify strategies to minimise the gap between healthy life expectancy and average life span. Cold-related injuries and symptoms have recently attracted attention, and studies on the relationship between blood pressure, falls, physical performance, and the thermal environment of housing have been reported. Based on previous studies, we hypothesised that people living in cold homes will receive certification for long-term care insurance earlier in life, indicating a shorter healthy life expectancy. This retrospective study involved 205 community-dwelling older adults living in Japan. Participants completed a self-report questionnaire about personal characteristics, housing, and perceived indoor temperature in their home during winter. Participants were divided into a Cold group and a Warm group based on perceived indoor temperature. Mean and minimum living room and bedroom temperatures differed between the Cold group and Warm group. On the other hand, mean, maximum, and minimum temperatures in the dressing room all differed significantly between the Cold group and the Warm group. Air conditioners were the only heating system that contributed to warmer indoor temperature. Maximum temperature was higher but minimum temperature was lower in houses with fan heaters, which may run intermittently and with short running time. Houses in which kotatsu systems or electric blankets were used tended to have colder indoor temperatures in the living room and bedroom. The Kaplan-Meier method was used to analyse the relationship between age at certification for needing long-term care insurance and perceived indoor temperature. Mean age at certification was 77.8 years in the Cold group and 80.6 years in the Warm group (p<0.01, generalised Wilcoxon test). Multivariate analysis by ANCOVA revealed a significant main effect of perceived indoor temperature, with the Cold group having a younger age at certification for needing long-term care (F(1, 197)=9.27, p<0.01). Estimated marginal means indicated that healthy life expectancy was 2.9 years shorter in the Cold group than in the Warm group even after adjusting for participant characteristics. When the relationship between measured indoor temperature and age at certification was tested, people living in houses with low indoor temperature (<14 °C) or high indoor temperature (≥18 °C) had a higher age at long-term care certification. People with low indoor temperature might spend longer time outside and use heating systems for shorter time. Since we could not grasp or control times going-out or using heating system, we conclude that relationship between measured indoor temperature and age at certification can support the previous result though, close investigations of indoor thermal environment in where older people lives are still needed. Our findings suggest that maintaining an appropriate indoor thermal environment could help prevent the need for long-term care.

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Quantitative improvement in workplace performance through biophilic design: A pilot experiment case study

Ayuso Sanchez J, Ikaga T, Vega Sanchez S

Energy and Buildings (Energy and Buildings) 177 316 - 328 2018.10

Research paper (scientific journal), Joint Work, ISSN 03787788

© 2018 Elsevier B.V. Numerous studies endorsed by the scientific community affirm that biophilic design in the workplace improves productivity and user well-being. However, it is necessary to go a step further and objectify the design criteria serving as an operator for productivity and well-being in design practice. In response to the challenges of how to measure the improvement of productivity and well-being through biophilic architecture design, the main contribution of this article is the development of a tool that allows to measure the predicted feature that improve productivity and well-being, based on a scientific method, which is tested by conducting a pilot experiment. A scheduled pilot experiment, as a small-scale version done in preparation for a major study, has been conducted to test a tool that quantifies the impact of biophilic design features on performance and well-being, to evaluate the influence of variables such as greenery and daylight on improving workplace performance, and look at biophilic design knowledge in greater depth. The role of natural indoor environments - understood as spaces within buildings provided with elements of nature - has received relatively little attention, compared to the number of studies evaluating occupant impact related to other characteristics of indoor environments derived from mechanical and electrical systems such as thermal factors, noise and vibration, ergonomics and office design. The present study is one of the first studies evaluating and measuring the combination of greenery and daylight into a biophilic design proposal. The results highlight an improvement in well-being, performance, creativity and health by introducing daylight and greenery into workplace design such as biophilic design features. The tool developed and tested in this pilot experiment opens a way to improve measured workplace performance to a much greater extent in contrast to the existing practice.

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Sustainability assessment of cities: SDGs and GHG emissions

Shun Kawakubo, Shuzo Murakami, Toshiharu Ikaga, Yasushi Asami

Building Research & Information (Informa UK Limited) 46 ( 5 ) 528 - 539 2018.07

Research paper (scientific journal), Joint Work, ISSN 09613218

The United Nations' (UN) sustainable development goals (SDGs), the core of the 2030 Agenda for Sustainable Development and the UN Paris Agreement, were adopted in 2015. Involvement of not only national governments but also all other stakeholders including local governments is important to promote sustainable development and to achieve the goals. The question arises, therefore, of what methods should be used to best implement and assess sustainability issues at a local level. In this light, a new version of Comprehensive Assessment System for Built Environment Efficiency (CASBEE), CASBEE for Cities, is introduced for assessing the sustainability of cities and communities around the world based on SDG indicators and greenhouse gas (GHG) emissions. The tool allows users to understand the sustainability of cities and communities based on quality (Q) and environmental load (L) perspectives. The sustainability assessments show that cities in developed countries tend to have good grades for Q, but bad grades for L, while cities in developing countries tend to have the opposite trend. This will assist cities and communities in both developed and developing countries to understand urgent problems and to identify effective solutions for sustainable development.

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EVALUATION OF RELATIONSHIP BETWEEN RESIDENCE RESILIENCY AND RESIDENTS' AWARENESS OF DISASTER PREVENTION

SATO Ryota, IKAGA Toshiharu, MURAKAMI Shuzo, SEIKE Tsuyoshi, OTSUKA Kaichi

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 83 ( 749 ) 615 - 623 2018.07

Research paper (scientific journal), Joint Work, ISSN 13480685

The severe damage caused by the Great East Japan Earthquake in 2011 highlighted the shortcomings in disaster reduction. Therefore, the concept of resilience has drawn much attention to reduce damage and to achieve restoration of services in addition to preventing damage; thus, new policy guidelines in various fields have been published.  To improve residence resiliency, it is important not only to prepare for physical needs, but to understand the risks during disasters, to take appropriate action, and to make homes safe to avoid injuries and accidents in everyday life. However, the actual extent to which residents have made these preparations is not properly understood. Factors affecting residence resiliency is unclear, and it is necessary to clarify this and to consider measures to promote resident preparation.  In this research, we conducted a questionnaire survey on residents’ disaster preparation and awareness to evaluate residence resiliency and analyze the factors affecting residence resiliency. The questionnaire survey results show that the higher the household income and the higher the age of the resident, the higher the residence resiliency. Residents living in areas affected by the Great East Japan Earthquake showed a relatively high resilience. In addition, factor analysis was conducted, and we extracted elements describing residence resiliency. Eight factors were extracted from questionnaires on resilience, and the factors were classified as “Risk understand 1”, “Risk understand 2”, “Life continuity”, “Action plan”, “Links with region”, “Equipment preparation”, “Daily safety”, and “Information”. Evaluating the resilience for each factor indicated that the “Links with region” and “Equipment preparation” factors are inadequate, and that information is provided according to these factors.  We analyzed the relationship between residents' awareness and residence resiliency by structural equation modeling. The results showed that concerns about primary damage and mutual help awareness affect disaster prevention awareness, and that disaster prevention awareness affects residence resiliency. Therefore, to improve residence resiliency, activities to improve mutual help awareness should be promoted and residents should be encouraged to recognize the risk of disaster and the possibility of damage. However, in the model we created, disaster prevention awareness only accounts for 26% of residence resiliency, and the effect of household income and age is large. Therefore, measures for promoting preparation among those with low income and among young people are important.

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Influence of residential performance on residents’ health status: Nationwide survey of environmental performance of detached houses and residents’ health status

Shun Kawakubo, Toshiharu Ikaga, Shuzo Murakami, Tanji Hoshi, Shintaro Ando

International Journal of Japan Architectural Review for Engineering and Design (JAR) (Wiley) 1 ( 2 ) 271 - 279 2018.01

Research paper (scientific journal), Joint Work, Accepted, ISSN 2475-8876

Previous studies have revealed the relationships between specific residential environmental factors and residents' health status. However, no study has considered the comprehensive health risk due to the overall residential environment. Therefore, a large-scale nationwide questionnaire survey was conducted using the CASBEE Health Checklist to examine the residential environment of detached houses and residents' health status. This analysis indicated that the overall residential environment is likely an important determinant of health and was associated with disease prevalence among residents.

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Effect of Office and Housing Environment on Mental and Physical Health and Workplace Productivity (part1) Statistical analysis based on questionnaire survey

四方路慶樹, 伊香賀俊治, 藤野善久, 平岡雅哉, 佐藤正章, 鈴木雄介, 権藤尚, 海塩渉, 関紅美花

Techinical Papers of Annual Meeting the Society of Heating,Air-conditioning and Sanitary Engineers of Japan (The Society of Heating,Air-Conditioning and Sanitary Engineers of Japan) 2018 ( 0 ) 185 - 188 2018

Research paper (scientific journal), Joint Work, Accepted, ISSN 1880-3806

執務者が長い時間を過ごす執務環境が心身の健康に影響を及ぼす可能性が既往研究により報告されているが、執務者の生活に大きく関わっている住環境や、メンテナンス・企業経営等の管理方法を考慮した包括的な検証は不十分である。そこで、執務環境と住環境が心身の健康と知的生産性に与える影響の包括的な検証を目的とした実態調査を実施した。結果として、良質な執務環境と住環境が心身の健康改善と知的生産性向上に寄与する可能性が示された。

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AN EXAMPLE OF CLUSTER ENERGY MANAGEMENT SYSTEM IN AGING SOCIETY

Terashima Kohei, Akada Hiroyasu, Kobayashi Yuriko, Sato Haruki, Ikaga Toshiharu

グランド再生可能エネルギー国際会議論文集 (特定非営利活動法人再生可能エネルギー協議会) 1 ( 0 ) 2018

Research paper (scientific journal), Joint Work, Accepted

Under the Paris Agreement, Japan promises reducing 26 % from greenhouse gas emissions in 2013 by 2030. We have proposed a concept of Cluster Energy Management System, CEMS, which can design a highly saving-energy network based on demand simulation of communities consisting various different residents. As an example of CEMS designing a good thermal and electricity demand-balance among a network of residential houses, commercial and nursing facilities is introduced. The network can use almost whole exhaust heat from distributed power plant such as fuel cell with solar power and thermal utilization. We can simulated saving about 40 % in prime-energy consumption and about 45 % reduction of CO2 emission by designing an example case of the CEMS, which combines fuel cells and electric vehicles in a community, where 200 families including elderly people are living. We concluded that it would be possible to reduce primary energy consumption and CO2 emission by nearly a half amount or more by introducing the CEMS.

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Relationship between indoor temperature in winter and Brain Healthcare Quotient

Matsumoto M., Ikaga T., Yamakawa Y., Uchida Y., Murakami S., Ando S., Mitsukura Y., Hayashi Y.

15th Conference of the International Society of Indoor Air Quality and Climate, INDOOR AIR 2018 (15th Conference of the International Society of Indoor Air Quality and Climate, INDOOR AIR 2018) 2018

Research paper (scientific journal), Accepted, ISSN 9781713826514

In Japan, where the population is aging, it is necessary to maintain mental and physical health over the long term in order to solve social problems such as increasing medical expenses. It has been suggested that exposure to cold adversely affects brain health. Thus, we hypothesized that the brain health of residents in cold houses would be worse than that of residents in warm houses. In the winter season from 2016 to 2017, we measured indoor temperature, conducted brain health tests using MRI examination, and administered questionnaire surveys for 59 residents of a town in northern Japan. The results of multiple regression analysis show that residents who had a cold living room had lower indexes representing the quality of cranial nerve fibers than residents who had a warm living room in winter.

AN EXAMPLE OF CLUSTER ENERGY MANAGEMENT SYSTEM IN AGING SOCIETY

Terashima Kohei, Akada Hiroyasu, Kobayashi Yuriko, Sato Haruki, Ikaga Toshiharu

グランド再生可能エネルギー国際会議論文集 (特定非営利活動法人再生可能エネルギー協議会) 1 2018

Research paper (scientific journal), Joint Work, Accepted

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Influence of environmental humidity on oral dryness among nursing home residents in Japan

Yukie Nakajima, Toshiharu Ikaga, Shintaro Ando, Tanji Hoshi

15th Conference of the International Society of Indoor Air Quality and Climate, INDOOR AIR 2018 (15th Conference of the International Society of Indoor Air Quality and Climate, INDOOR AIR 2018) 2018

Research paper (scientific journal), Joint Work, Accepted

Maintaining good quality of life among elderly residents of nursing homes is becoming more important as their numbers increase with the ageing of society. Dry mouth, or xerostomia, is one condition that must be prevented, as it can lead to various serious diseases. However, older people are susceptible to dry mouth due to reduced lip closing force. In this study, a field survey of the indoor environment of nursing homes and oral dryness among nursing home residents was conducted in winter 2015. Twenty-seven facilities were classified as dry or moist based on measured indoor humidity. Ordered logistic regression analysis showed that the likelihood of dry mouth was significantly lower among patients residing in the moist group compared with the dry group.

Relationship between Bath-related Deaths and Low Air Temperature.

Masaru Suzuki, Toshiharu Ikaga, Shingo Hori

Internal medicine (Tokyo, Japan) (JAPAN SOC INTERNAL MEDICINE) 56 ( 23 ) 3173 - 3177 2017.12

Research paper (scientific journal), Joint Work, Accepted, ISSN 0918-2918

Objective Bath-related sudden cardiac arrests occur frequently in Japan. Although previous studies have reported that most fatal events occurr in winter, the reason why such events exhibit a seasonal variation has not been elucidated. In this study, we hypothesized that the occurrence of bath-related deaths was correlated with a low air temperature. Methods This prospective cross-sectional observational study was conducted in the Tokyo Metropolitan area between October 2012 and March 2013. Data were collected for all cases involving the activation of the emergency medical system because of an accident or acute illness related to bathing that occurred in Tokyo during the study period. In particular, elderly (≥65 years) cardiac arrest victims who had been found in a bathtub filled with water were enrolled. The relationship between the daily number of cardiac arrest events and the lowest daily air temperature in Tokyo was studied using a nonlinear regression model. Results A total of 3,624 bath-related events were registered in this study. Among these events, 1,081 deaths of elderly individuals who had been found in a bathtub filled with water were recorded. A close correlation was observed between the daily number of events and the lowest daily air temperature. This correlation was described by the following equation: y=8.38e-0.07x, where y was the daily number of cardiac arrests and x was the lowest daily air temperature. Conclusion A low air temperature was closely correlated with the occurrence of bath-related cardiac arrest.

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Life Cycle Assessment for Commercial Buildings

SATO Masaaki, IKAGA Toshiharu

Journal of Life Cycle Assessment, Japan (The Institute of Life Cycle Assessment, Japan) 13 ( 2 ) 111 - 117 2017

Research paper (scientific journal), Joint Work, Accepted, ISSN 18802761

Current Situation of LCA for Buildings used by National / Local Governments and Private Companies, and Development for Health Impact Assessment

IKAGA Toshiharu

Journal of Life Cycle Assessment, Japan (The Institute of Life Cycle Assessment, Japan) 13 ( 2 ) 104 - 110 2017

Research paper (scientific journal), Joint Work, Accepted, ISSN 18802761

This article introduces the current situation of LCA for buildings. The research and development on LCA method of buildings started in 1990 as an activity of the Architectural Institute of Japan, and it became LCA guideline of buildings. By using of this guideline, the cost effectiveness evaluation tool to mitigate climate change was developed and applied by national and local government, and widely used by many private companies. As well as simplified LCA method was developed and introduced into the comprehensive assessment system for built environment efficiency named “CASBEE: Comprehensive Assessment System for Built Environment Efficiency” for all kind of buildings such as detached houses and large-scale commercial buildings. Furthermore, the human health impact assessment methods associated with indoor environment including indoor air pollution are conducted.

全国二次医療圏を対象とした傷病別入院患者割合と都市・住環境因子の比較

鈴木健太郎, 伊香賀俊治, 村上周三, 川久保俊

環境工学I (Architectural Institute of Japan) ( 2016 ) 1195 - 1196 2016.08

Research paper (scientific journal), Joint Work, Accepted

A STUDY ON ECONOMIC IMPACT OF ENVIRONMENTAL EFFICIENCY AND INTELLECTUAL PRODUCTIVITY CONTRIBUTION ON RENTS

ITO Masato, MURAKAMI Shuzo, IKAGA Toshiharu, HAYASHI Tatsuya, TAKAI Hiroaki, MATSUNAGA Koichi

AIJ Journal of Technology and Design (Architectural Institute of Japan) 22 ( 52 ) 1053 - 1056 2016

Research paper (scientific journal), Joint Work, Accepted, ISSN 18818188 13419463

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EVENT HISTORY ANALYSIS OF INDOOR THERMAL ENVIRONMENT AND CARE PREVENTION OF RESIDENTS:A field survey on the effect of winter indoor thermal environment on care requirements

HAYASHI Yukie, IKAGA Toshiharu, HOSHI Tanji, ANDO Shintaro

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 81 ( 729 ) 901 - 908 2016

Research paper (scientific journal), Joint Work, Accepted, ISSN 1881817X 13480685

As ageing of the population progresses, long-term care becomes a more pressing health issue. In Japan, the gap between healthy life expectancy and average life span is expected to grow; therefore, it is necessary to extend healthy life expectancy while minimising the need for long-term care. The effect of indoor air temperature on the health of the elderly has recently attracted attention. Thus, in this study, we clarify the relationship between the indoor thermal environment and the care requirements of the elderly.  This research was conducted as a field study comprising actual measurements of indoor thermal environment, questionnaire surveys, and data collection from face sheets in 2014. The study area was Senri New Town, Osaka Prefecture, Japan. Participants were elderly residents (65-91 years) who were using a day service facility. The indoor air temperature 1.1 m above the floor was measured over approximately 2 weeks in the living room, bedroom, corridor, and dressing room at 5-min intervals. Relative humidity was also measured in the living room and bedroom concurrently. Questionnaire surveys regarding personal factors and housing were distributed. Data about health conditions and diseases requiring care were also collected. Data about care level, date of care certification, and care certification period were collected from long-term care insurance cards.  Regarding the frequency of feeling cold in each of the rooms, participants who answered “1) Frequently” and “2) Sometimes” were assigned to the high-frequency group, whereas those who answered “3) Seldom” and “4) Never” were assigned to the low-frequency group. Mean living room and dressing room temperatures were significantly lower in the high-frequency group than in the low-frequency group (p < 0.01). Mean room temperatures were also compared between houses with different insulation performance. The mean room temperatures in the corridors and dressing rooms were lowest for “Pre-1980 standards” households, and highest for “Over 1992 standards”.  The results describe the differences in room temperature between the frequency of feeling cold in dressing rooms, which is affected by low insulation performance, and verifies the association between indoor thermal environment and long-term care through subjective evaluation. The Kaplan-Meier (KM) method was used to analyse the speed of certification for the participants' long-term care needs. The age at which half of the group was certificated was 76 years in the high-frequency group and 80 years in the low-frequency group (p < 0.05). The chi-square test showed that there were no significant differences in personal factors between the two groups, confirming that the result in KM method could be explained by the difference in the thermal environment in the dressing rooms.  Our results suggest that it is necessary to maintain an appropriate indoor thermal environment to prevent the need for long-term care, especially the indoor thermal environment in rooms other than the living room, such as the dressing room. The results of this study are expected to promote improvements in the indoor thermal environment, thereby contributing to care prevention among frail elderly people.

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COMPARISON OF HOME BLOOD PRESSURE BEFORE-AND-AFTER MOVING TO HIGH THERMAL INSULATION PERFORMANCE HOUSES:A field survey on the effect of indoor thermal environment on blood pressure in winter (Part III)

UMISHIO Wataru, IKAGA Toshiharu, ANDO Shintaro, OTSUKA Kuniaki

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 81 ( 722 ) 357 - 366 2016

Research paper (scientific journal), Joint Work, Accepted, ISSN 1881817X 13480685

A cardiac disease is the second most common cause of death and a cerebrovascular disease is the fourth, a major cause of which is hypertension. Hypertension is an asymptomatic disease, which is called “silent killer”, affecting one-third of the population. Therefore, it is essential not only “high risk approaches” which are measures for hypertensive individuals such as treatment with an antihypertensive drug but also “population approaches” which are measures to reduce blood pressure (BP) of entire nation toward prevention of Hypertension.  Against this background, the effects of the indoor thermal environment on BP have attracted attention because it affects asymptomatic individuals. Now some studies on the relationship between BP and indoor thermal environment are accumulated. But most of the studies are cross-sectional studies, so there is a real need for follow-up studies and actual proof of causal correlation between BP and indoor thermal environment. This study aimed to demonstrate antihypertensive effects by moving to high thermal insulation performance houses.  Follow-up studies on home BP and indoor temperature was conducted before and after moving in winter 2014 and 2015. Home BP was measured by participants twice daily: before getting into bed in the evening and after getting out of bed in the morning for two weeks. Indoor temperature at 1.1 m above the floor was measured in the living room, bedroom, bathroom, and dressing room at 10-min intervals. During the survey periods, participants recorded the wake time and bedtime each day in a diary. Questionnaire surveys on personal factors and housing were also carried out. Besides, questionnaire surveys on housing were distributed to building contractor to get a reliable answer.  Thermal insulation performance of houses before moving was either “pre-1980 standards” or “1980 standards.” While thermal insulation performance of houses after moving satisfied “1999 standards”: heat loss coefficient (Q value) of houses after moving was 1.9 W/m2K, corresponding gap area (C value) was 0.4 cm2/m2 on average. Average daily outdoor temperature of before moving survey periods (5.7 °C) was nearly equal to average daily outdoor temperature of after moving survey periods (5.1 °C). The living room temperature gap between before and after moving was the largest at a wake-up time. At 6 o'clock, living room temperature after moving was higher by 2.0 °C than living room temperature before moving. In addition, the lowest temperature had increased and the highest temperature had decreased in each room. So, stabilizing effects of indoor temperature by moving were recognized.  Systolic BP (SBP) decreased by 1.5 mmHg per 1 °C increase in indoor air temperature and standard deviation (SD) of SBP improved by 2.3 mmHg per 1 °C improvement in SD of indoor air temperature in a group over 125 mmHg. Therefore, stabilization of indoor temperature has stabilizing effects on BP. However, there were several participants whose houses got colder and more unstable after moving. To examine factors related to indoor temperature changes, a comparison of indoor temperature between before and after moving by patterns of moving was carried out. As a result, moving from a single-family house to a single-family house and from a wooden house to a wooden house became warmer and improved SD of indoor temperature. On the other hand, moving from a condominium to a single-family house and from a reinforced concrete house to a wooden house became colder. Moreover, not heating a room after moving caused a sharp decrease in indoor temperature. So, it is not satisfied only by moving to high thermal insulation performance houses but paying attention to house form and structure and adequately heating a room to improve BP value and stability of BP.

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特集熱中症すまいと熱中症

伊香賀俊治

公衆衛生 (株式会社医学書院) 79 ( 6 ) 397 - 400 2015.06

Research paper (scientific journal), Joint Work, Accepted, ISSN 03685187

Influence of residential environment on residents’ health promotion

Shun Kawakubo, Toshiharu Ikaga, Shuzo Murakami, Tanji Hoshi, Shintaro Ando

Healthy Buildings Europe 2015, HB 2015 - Conference Proceedings (Healthy Buildings Europe 2015, HB 2015 - Conference Proceedings) 2015-May 2015

Research paper (scientific journal), Joint Work, Accepted

Housing plays a critical role in human life, and the establishment of a residential environment that promotes the health of its residents is a pressing issue. Numerous studies on housing have been previously conducted in this social context; however, only a few have considered the comprehensive health risk due to the overall residential environment. In the present study, therefore, a large-scale nationwide self-rated questionnaire survey was conducted to examine the residential environment of detached houses and its impact on residents’ health status. A tool used in the Comprehensive Assessment System for Built Environment Efficiency (CASBEE), namely, the CASBEE Health Checklist, was distributed to various detached houses throughout Japan to assess the overall residential environment. The CASBEE Health Checklist covers residential environmental elements concerning thermal environment, acoustic environment, light environment, hygiene, safety, and security. Respondents were also asked about their current health status and that of family members. The questionnaire results were cross-tabulated, and odds ratios and significance probabilities (Fisher's exact test) were calculated. Results showed that the overall residential environment was likely an important determinant of health and was associated with prevalence of certain chronic diseases among residents. Odds ratios tended to be less than 1.0 in all cases, indicating that low disease prevalence was associated with a good residential environment.

Study on business scheme of a community-level decentralized and self-reliant energy network

Kuzuki, R., Murakami, S., Ikaga, T., Yamada, K., Kawayoke, T., Ikuta, Y., Komiyama, T.

Journal of Environmental Engineering (Japan) (Journal of Environmental Engineering (Japan)) 80 ( 708 ) 169 - 176 2015

Research paper (scientific journal), Joint Work, Accepted, ISSN 1881-817X

Community-level decentralized and self-reliant energy network is expected to contribute to create a sustainable community as well as its self-vitalization and energy resiliency. But implementation of this system requires consensus among variety of stakeholders and long payback period, which are major hurdles. This study proposes the following concept and methods; (1)PPP business scheme consisting of two types of actors; "community-level energy network infrastructure operating company" and "on-site energy production and service providers". (2)Proper re-allocation of cost and co-benefits among stakeholders by taking advantage of opportunities of adjusting tariffs, taxes, subsidies for the purpose of equalizing each stakeholder's B/C.

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夏季・冬季の室内温熱環境が睡眠に及ぼす影響のマルチレベル分析

大橋知佳, 伊香賀俊治, 伊藤真紀, 海塩渉

Techinical Papers of Annual Meeting the Society of Heating,Air-conditioning and Sanitary Engineers of Japan (The Society of Heating,Air-Conditioning&Sanitary Engineers of Japan) 2015.6 ( 0 ) 253 - 256 2015

Research paper (scientific journal), Joint Work, Accepted, ISSN 18803806

睡眠の問題は重大な健康被害をもたらす。近年、室内温熱環境と睡眠の関係に注目が集まりつつあるが、季節を通して調査を行った例は少なく、その検証は不十分である。そこで本研究では、夏季・冬季の室内温熱環境が睡眠に及ぼす影響を明らかにすることを目的として、2014年の夏季と冬季に実態調査を行った。マルチレベル分析の結果、夏季は寝室の室温1℃上昇に伴い0.2%睡眠効率が低下し、冬季は室温1℃低下に伴い0.8%睡眠効率が低下することが示された。

The effects of light and visual environment in office support spaces on fatigue, sleepiness, and workplace productivity through the autonomic nervous system

Ogawa, S. and Ikaga, T. and Ichihara, M. and Harimoto, K.

Healthy Buildings Europe 2015, HB 2015 - Conference Proceedings (Healthy Buildings Europe 2015, HB 2015 - Conference Proceedings) 2015-May 2015

Research paper (scientific journal), Joint Work, Accepted

Improvements in workplace productivity bring significant benefits to companies, and so previous research has focused on how the indoor office environment affects workplace productivity. Recently, the effect of support spaces, such as “refresh corners”, on workplace productivity has been investigated. Light and the visual environment also affect the fatigue and sleepiness of workers through the autonomic nervous system. Hence, support spaces could improve workplace productivity by alleviating fatigue and sleepiness. In this study, we conducted a human subject experiment in the autumn of 2013. The working efficiency of participants was measured during simulated work while they used a support space with different light and visual environments. In addition, the participants wore a heart rate monitor to measure their autonomic nervous state and they answered a questionnaire on fatigue and sleepiness before and after support space use. An open support space activated the parasympathetic nervous system and reduced fatigue. Moreover, having blinds open to allow daylight in also activated the sympathetic nervous system and decreased sleepiness. Lower levels of sleepiness before work improved working efficiency for idea generation. These results suggest that using open support spaces with daylight reduces fatigue and sleepiness, and increases workplace productivity.

Fact finding survey on the regional environment and the physical activity and exercise habits of Japanese children

Satoko Omi, Toshiharu Ikaga, Kimihiro Hino, Shintaro Ando, Takako Amemiya

Healthy Buildings Europe 2015, HB 2015 - Conference Proceedings (Healthy Buildings Europe 2015, HB 2015 - Conference Proceedings) 2015-May 2015

Research paper (scientific journal), Joint Work, Accepted

With the recent reduction in physical activity seen in Japanese children, reduced ability to exercise and increasing prevalence of overweight and obesity have become serious health concerns. Therefore, governmental agencies have promoted the improvement of the regional environment to encourage physical activity in children. This study shows, using a questionnaire survey and actual measurement of physical activity of children and parents, that the frequency at which children use community centers and gyms and participate in community activities affects frequency of exercise. The number of daily steps in children who did not receive sufficient daily exercise (<10,000 steps/day) increased by about 3,000 steps/day when they participated in community activities.

A PROPOSAL AND PRACTICE OF “CITY ECOX”, A ZEH PROTOTYPE OF CITY APARTMENTS, IN ENEMANE HOUSE 2014

ISHIWATA Maya, TOMIYAMA Souki, YONEZAWA Seiya, KITAGATA Hiroshi, KITA Nanae, SANUKI Masashi, KOBAYASHI Miko, TAKEMURA Yuki, MAE Masayuki, SEIKE Tsuyoshi, YOSHIDA Motoki, MINAMI Yusuke, CHIKADA Toshiya

AIJ Journal of Technology and Design (Architectural Institute of Japan) 21 ( 47 ) 387 - 392 2015

Research paper (scientific journal), Joint Work, Accepted, ISSN 1341-9463

ENEMANEHOUSE2014, a contest in which 5 universities design, construct, and measure Zero-Energy-Houses (ZEH), was held as a part of a project by Agency for Natural Resources and Energy. The University of Tokyo established a consortium with various enterprises and proposed a ZEH prototype of city apartment called “CITY-ECOX”. CITY-ECOX has flexible spatial structure and technologies that can be customized according to the climate of a construction site and lifestyles of house owners. A real size CITY-ECOX was built in Tokyo, January 2014, and its environmental performance was measured. This paper shows design of CITY-ECOX and result of its operation.

Experimental study on sleep quality affected by non-stationary thermal environmental control in summer

本多英里, 伊香賀俊治, 岡島慶治, 海塩渉

Research paper (scientific journal), Joint Work, Accepted, ISSN 18803806

睡眠の質低下を引き起こす要因の一つとしては、夏季の蒸し暑さが挙げられ、冷房を使用した適切な暑さ緩和対策が求められている。既報においては、冷房の連続運転が睡眠に与える影響を検証し、入眠時および睡眠中の後半に適切な温熱環境が異なる可能性及びタイマー運転の検証の必要性を示唆した。そこで本研究では、非定常温熱環境制御が睡眠の質に与える影響を明確にするため、被験者実験を実施し、非定常温熱環境制御が睡眠の質向上に寄与する可能性を示した。

COST-BENEFITS ANALYSIS OF NON-ENERGY BENEFITS (NEB) FOR EACH STAKEHOLDERS AND CONSIDERATION FOR REDISTRIBUTION OF NEB:Study on low-carbon communities and cities by use of decentralized energy network

MIZUISHI Tadashi, IKAGA Toshiharu, MURAKAMI Shuzo, KUZUKI Ryota, YAMADA Koya

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 78 ( 684 ) 175 - 181 2013

Research paper (scientific journal), Joint Work, Accepted, ISSN 13480685 1881817X

1. This study has carried out a cost benefits analysis for each stakeholder in an attempt to develop low-carbon communities and cities by implementing regional cogeneration systems and leasing photovoltaic systems to commercial buildings. 2. As a result, the economic benefits for energy service provider acting as an investor have been proved when non-energy benefits (NEBs) are accounted. In addition, numerous benefits to stakeholders other than investor have been proved. Also, subsidies by public sector (National, Local Government) will increase the economic efficiency for energy service provider (investor). 3. Since building owners and building users will gain NEBs such as of increase in real estate value, risk reduction (contribution of business and living continuity plan (BLCP), regulatory compliance etc) and maintenance cost reduction, possibility for redistribution of NEBs to the energy service provider (investor) in the form of service charge (rent, energy expense etc) have also been considered.

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Hierarchical structure analysis of adult residents' health by developing multiple indicators model: A Comparative study among locales of health related factors structure of housing and regional environment

Shintaro Ando, Toshiharu Ikaga, Yasuyuki Shiraishi, Tanji Hoshi, Kenichi Kawamura, Shun Kawakubo, Kazue Oshige

Journal of Environmental Engineering (Journal of Environmental Engineering) 77 ( 675 ) 389 - 397 2012.05

Research paper (scientific journal), Joint Work, Accepted, ISSN 1348-0685

A questionnaire survey was administered to adult residents of three locales: a large city (Kitakyushu city)
a small city (ObuseTown)
and a rural village (Yusuhara town), in order to clarify the hierarchical structure of health related factors of housing and regional environment dependent on urban structure and scale. As a result of structural equation modeling, health related factorsmodel in Yusuhara was shown that 35% of residents' overall health may depend on their housing and regional environment, and it was the largest percentage of three locales. Besides, differences were found among the health related factors structure. These results indicate that design guidelines for health promotion that correspond to the urban structure and scale will be required.

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Outline of the approach to low carbonisation by strengthening CASBEE for new construction (2010 edition)

Masaaki Sato, Shuzo Murakami, Toshiharu Ikaga, Takashi Yanai, Tatsuya Hayashi, Junko Endo

International Journal of Sustainable Building Technology and Urban Development (Informa UK Limited) 3 ( 1 ) 15 - 20 2012.03

Research paper (scientific journal), Joint Work, Accepted, ISSN 2093-761X

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FACTORS OF CHILDREN'S PARTICIPATION IN COMMUNITY ACTIVITIES AND STRUCTURAL RELATIONSHIP TO THEIR HEALTH: Focusing on parents' attitude and participation and community safety

HINO Kimihiro, SHIRAISHI Yasuyuki, HOSHI Tanji, IKAGA Toshiharu

Journal of Architecture and Planning (Transactions of AIJ) (Architectural Institute of Japan) 77 ( 679 ) 2119 - 2125 2012

Research paper (scientific journal), Joint Work, Accepted, ISSN 1340-4210

Urbanization and change of lifestyle deprive children of their chance to participate in community activities. This paper analyses the structural relationship of factors of children's participation and their health factors focusing on community safety and parents' attitude toward community activities. A questionnaire was conducted to elementary and junior high school students and their parents in Kume Area, Matsuyama City where residents are earnest over various activities for community safety. In conclusion, it is suggested that children's participation has significant relationship with their physical and mental health and that they feel sense of community if they feel safe in the community.

Elucidating health determinant factors of housing and regional environment by conducting follow-up survey

Shintaro Ando, Toshiharu Ikaga, Yasuyuki Shiraishi, Tanji Hoshi, Shun Kawakubo

10th International Conference on Healthy Buildings 2012 (10th International Conference on Healthy Buildings 2012) 3 2587 - 2592 2012

Research paper (scientific journal), Joint Work, Accepted

Improvement of living environment quality of life (QOL) is increasingly attracting attention as a factor in disease prevention. We administered questionnaires to adult residents of a suburb of Kitakyushu City, Japan, in October 2009 and October 2011, with the aim of evaluating chronological changes in resident health and changes in the housing and regional environment over those two years. Cause-and-effect relations were considered through structural equation modeling (SEM) using a cross-lagged effects model and a synchronous effects model. Analysis of the results indicates that the housing and regional environment affects resident health. The present study quantified living environment value according to reported resident satisfaction. In addition, further studies with an increased sample size may be beneficial. Topics for future research include evaluation using objective indicators to strictly elucidate the causal relationship between resident health and living environment.

Housing and community for health promotion

MURAKAMI Shuzo

Japanese Journal of Health Education and Promotion (JAPANESE SOCIETY OF HEALTH EDUCATION AND PROMOTION) 20 ( 4 ) 313 - 322 2012

Research paper (scientific journal), Joint Work, Accepted, ISSN 13402560

A Forecast of Effective Global Warming Countermeasures for the Residential Sector in China for the year 2050

Rui Xing, Toshiharu Ikaga

JOURNAL OF ASIAN ARCHITECTURE AND BUILDING ENGINEERING (ARCHITECTURAL INST JAPAN) 10 ( 1 ) 221 - 225 2011.05

Research paper (scientific journal), Joint Work, Accepted, ISSN 1346-7581

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4041 放射冷暖房による温熱環境が満足度と作業効率に与える影響の調査(環境工学)

木村昌人, 伊香賀俊治, 平山禎久, 小林達也, 佐藤啓明

日本建築学会関東支部研究報告集 (Architectural Institute of Japan) ( 81 ) 161 - 164 2011.03

Research paper (scientific journal), Joint Work, Accepted

DEVELOPMENT OF COMPREHENSIVE ASSESSMENT TOOL FOR THE BUILT ENVIRONMENT OF CITIES: CASBEE-City

Shuzo MURAKAMI, Shun KAWAKUBO, Yasushi ASAMI, Toshiharu IKAGA, Nobuhaya YAMAGUCHI, Shinichi KABURAGI

AIJ Journal of Technology and Design (Architectural Institute of Japan) 17 ( 35 ) 239 - 244 2011.02

Research paper (scientific journal), Joint Work, Accepted, ISSN 1341-9463

This paper introduces a comprehensive assessment tool of the built environment of cities, referred to as "CASBEE-City". The tool supports local governments and other stakeholders in identifying environmental, social and economic characteristics of their cities and to quantify the effectiveness of city-led policies. As for the other CASBEE tools, CASBEE-City also implements the concept of environmental efficiency and allows evaluation of a city from two aspects simultaneously: the aspect of decreasing negative environmental load emitted outside the city, and that of improving environmental quality and activities inside the city. It is expected to contribute to the realization of sustainable cities.

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Analytic study on woody material flows in view of carbon reduction: Discussing utilization of building-related woody waste & forest wood residues as biomass

Kobayashi, K. and Nakajima, S. and Tsunetsugu, Y. and Ikaga, T.

Journal of Environmental Engineering (Journal of Environmental Engineering) 76 ( 659 ) 91 - 96 2011

Research paper (scientific journal), Joint Work, Accepted, ISSN 13480685 1881817X

Using material flowcharts on wood and carbon, the study was made as follows: 1) With flowcharts developed on building-related woody waste and forest, wood residues, the current status was analyzed. 2) Through field survey, regional supply-demand imbalance was revealed as a major obstacle to of wood residue utilization 3) Subsequently, carbon flow analyses resulted in different carbon evaluations depending on whether fixed carbon was considered or not. but either case showed utilization of wood residues has substantial effects on fixed-carbon increase. 4) The study concludes that utilization of wood residues can help bring about a lower carbon society.

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A 2050 CO <inf>2</inf> emissions forecast model of urban residential buildings in Shanghai

Xing, R. and Ikaga, T. and Oshiro, K. and Kimoto, K.

AIJ Journal of Technology and Design (AIJ Journal of Technology and Design) 16 ( 34 ) 1061 - 1064 2010

Research paper (scientific journal), Joint Work, Accepted, ISSN 13419463 18818188

These years residential energy consumption has been increasing sharply in China along with the high economic growth. Thus people pay much more attention to the issues of reducing the energy consumption and CO 2 emission. This study chose Shanghai, a big city of China as a subject, and developed a Macro-model to forecast the CO 2 emission of residential buildings up to 2050. By combining such Global warming count measures into the Macro-model it was able to forecast the CO 2 emission of Shanghai's residential buildings in several energy-efficient scenarios.

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Developing a LCA database of imported wood materials

Oshiro, K. and Ikaga, T. and Hondo, H.

AIJ Journal of Technology and Design (AIJ Journal of Technology and Design) 16 ( 33 ) 609 - 614 2010

Research paper (scientific journal), Joint Work, Accepted, ISSN 13419463 18818188

Wood is well-recognized as a renewable resource that can contribute to the reduction of environmental load and it has long been used as a material in the building sector. The LCA database for buildings (established by the Architectural Institute of Japan) has been developed and utilized to evaluate the reduction of environmental load through the use of wood materials. However, this method does not evaluate the environmental load incurred through the production and transportation of imported wood materials, although wood materials are imported into Japan in large volumes. Therefore, this study aims to develop a database which includes the environmental load of imported wood materials from several countries and regions.

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Overview of energy consumption and GHG mitigation technologies in the building sector of Japan

Shuzo Murakami, Mark D. Levine, Hiroshi Yoshino, Takashi Inoue, Toshiharu Ikaga, Yoshiyuki Shimoda, Shuichi Miura, Tomoki Sera, Masahiro Nishio, Yasuhiro Sakamoto, Wataru Fujisaki

Energy Efficiency (Energy Efficiency) 2 ( 2 ) 179 - 194 2009.01

Research paper (scientific journal), Joint Work, Accepted, ISSN 1570646X 15706478

This paper outlines the energy consumption and greenhouse gas emission trends in the residential and commercial sectors in Japan. The results showed that the increase in residential energy consumption in Japan is mainly caused by the widespread use of heating equipment, hot water supply apparatus, and other household electrical appliances. On the other hand, it was indicated that the increase in commercial energy use is mainly due to the increase of the floor area of buildings, particularly hotels, hospitals, and department stores. The paper also describes political measures to promote energy conservation, including the building energy conservation standard, Comprehensive Assessment System for Building Environmental Efficiency, top runner programs, financial incentives, and the dissemination of the Cool Biz concept. Finally, the projections of CO2 emissions until 2050 are presented. © Springer Science+Business Media B.V. 2009.

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Designing a system to apply an assessment method of buildings for all lifecycle stages based on the concept of eco-efficiency

Endo J., Murakami S., Ikaga T.

ASTM Special Technical Publication (ASTM Special Technical Publication) 1503 STP 63 - 73 2009

Research paper (scientific journal), Joint Work, Accepted, ISSN 9780803145078

CASBEE (Comprehensive Assessment System for Building Environmental Efficiency) is an environmental labeling method for buildings, based on assessment of the environmental performance of buildings. In CASBEE, BEE (Building Environmental Efficiency) was developed as a new indicator for assessment following the concept of eco-efficiency. With the increasing BEE value, the total environmental performance of buildings is labeled from the highest performance. The framework of basic and extended CASBEE tools as a structured assessment system is called the "CASBEE family." CASBEE consists of a set of four basic assessment tools; namely, "CASBEE for Pre-design" (CASBEE-PD), "CASBEE for New Construction" (CASBEE-NC), "CASBEE for Existing Building" (CASBEE-EB), and "CASBEE for Renovation" (CASBEE-RN). These correspond to the individual stages of the building's lifecycle. There are also needs for detailed assessment targeting specific environmental aspects. "CASBEE-HI," as an extended tool, assesses efforts made in buildings to alleviate the heat island effect. A new tool called "CASBEE for Urban Development" (CASBEE-UD) is developed for assessment of a group of buildings. Some local authorities introduced CASBEE into their building administration as assessment methods for their sustainable building reporting systems. This requires building owners to submit a planning document assessing the environmental performance of their buildings to the authorities. In April 2004, the city of Nagoya introduced "CASBEE Nagoya." Introduction of CASBEE followed in the city of Osaka, Yokohama, Kyoto, and other municipals. These local systems require some modification in CASBEE to reflect their local characteristics, such as climate and prioritized policies. Copyright © 2008 by ASTM International.

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Study on sleeping environment using human physiological model

Takayanagi, E. and Ikaga, T. and Omori, T. and Kato, A.

9th International Conference and Exhibition - Healthy Buildings 2009, HB 2009 (9th International Conference and Exhibition - Healthy Buildings 2009, HB 2009) 2009

Research paper (scientific journal), Joint Work, Accepted

Heat island phenomenon has significantly become worse in Tokyo metropolitan area in recent years. This leads to a drastic increase of patients with sleep disorder. The sleeping environments are much affected by the building performance and the ways occupants live in their houses. Interaction of human physiology and the thermal environment throughout the sleeping time makes it difficult to evaluate the sleeping environments. In this paper, we analyzed a sleeping environment by means of coupled simulations of the heat and airflow network model and Computational Fluid Dynamics (CFD) incorporated with thermoregulation model. Results showed that the use of air conditioner being operated to adapt to human metabolism can be effective to lower the core temperature and lead to a good sleep.

Environmental performance evaluation of vernacular architectures through CASBEE

Shindo, K. and Ikaga, T. and Murakami, S. and Deguchi, K.

9th International Conference and Exhibition - Healthy Buildings 2009, HB 2009 (9th International Conference and Exhibition - Healthy Buildings 2009, HB 2009) 2009

Research paper (scientific journal), Joint Work, Accepted

Vernacular architectures exhibit high environmental performance. In this study, we evaluate the environmental performance of vernacular architectures quantitatively and comprehensively through CASBEE in order to promote sustainable buildings. On the basis of this intention, we analyzed the indoor environment of vernacular architectures from the perspective of environmental engineering by taking on-site measurements and using CFD numerical analysis. In this study, we focused our attention on Water Housing in Malaysia. The result of evaluating the environmental performance through CASBEE was that Water Housing exhibited a high environmental performance when both the environmental load and quality were included. Water Housing is more comfortable than a local house above the land and it offers effective evaporative cooling as a result of using water and provides proper ventilation. The assessment introduced here demonstrates both the environmental performance of vernacular architectures from multiple perspectives and the efficiency of CASBEE as an environmental performance visualization tool.

Intelligent optimal control of thermal comfort using response surface method

Kato, A. and Ikaga, T. and Murakami, S. and Tsutsui, H. and Ueda, H.

9th International Conference and Exhibition - Healthy Buildings 2009, HB 2009 (9th International Conference and Exhibition - Healthy Buildings 2009, HB 2009) 2009

Research paper (scientific journal), Joint Work, Accepted

Optimal control of HVAC system is required because of its considerable influence on workplace-productivity, health and global environment. In this study, we developed an optimal HVAC control system using Response Surface Method by Spline, which calculates optimal control conditions on the basis of cause-and-effect model of thermal comfort, outdoor environment and control parameters created by building's operational data. Experimental study was conducted to verify the effectiveness of developed method by applying it on optimization problem of thermal comfort in several zones. We concluded that our method is practicable and efficient to achieve multi-objective optimization control on HVAC system.

A comparative analysis of the unit energy consumption in the commercial sector

Hirano, Y. and Tonooka, Y. and Ikaga, T.

Journal of Environmental Engineering (Journal of Environmental Engineering) 73 ( 633 ) 1331 - 1339 2008

Research paper (scientific journal), Joint Work, Accepted, ISSN 13480685 1881817X

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Development of life cycle impact assessment methods for the health damege by indoor air pollution: Study on health damage causes by indoor air pollution

Narita, N. and Murakami, S. and Ikaga, T. and Sakabe, K. and Itsubo, N.

Journal of Environmental Engineering (Journal of Environmental Engineering) 73 ( 627 ) 695 - 700 2008

Research paper (scientific journal), Joint Work, Accepted, ISSN 13480685 1881817X

There are so many chemical substances around us today. On the other hand, new houses are significantly air tight by standards of energy saving policy and it is very difficult to exchange between indoor air and fresh outdoor air. As a result, indoor air quality becomes worse, and health concerns have been an increasing social problem. The studies for these problems have been developed in the several fields, such as Building Environmental Engineering, Medical Science and in other areas so on. However, to solve this problem fundamentally, the comprehensive and quantitative assessments from the generation of chemical substances to onset of symptoms are needed. In this study, the health damages by indoor air pollutants are evaluated comprehensively following the environmental assessment tool, LIME (Life-cycle Impact assessment Method based on Endpoint modeling) developed by Advanced Industrial Science and Technology. Theoretically it is very difficult to evaluate sick-building syndromes, because these symptoms are extremely variable from person to person, and there has been no research in the world in these areas. Therefore, the data offered by a special hospital for sick-building syndromes are used with medical specialists in this study. A new assessment tools for indoor air pollutants is developed for the first time.

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Current Situation of Combined LCA and LCC Method of Buildings Used by National/ Local Governments and Private Companies

IKAGA Toshiharu

Journal of Life Cycle Assessment, Japan (The Institute of Life Cycle Assessment, Japan) 4 ( 1 ) 19 - 26 2008

Research paper (scientific journal), Joint Work, Accepted, ISSN 18802761

The research on LCA method of buildings started in 1990 as an activity of the Architectural Institute of Japan, and it became LCA guideline of buildings. By using of this guideline, the cost effectiveness evaluation tool to mitigate climate change was developed and applied by the public building department, the Ministry of Land, Infrastructure and Transport as a operation tool for Green government design guideline in 1998. A similar evaluation tool that suits each climate of various regions was developed and applied by local governments and private companies. As well as LCA, the comprehensive assessment system for building environmental efficiency named “CASBEE” was developed supported by the Ministry of Land, Infrastructure and Transport. Since 2004, more than 1300 buildings have been assessed and ranked by national government, local governments and private companies using CASBEE tool, and in 2007, CASBEE was revised to contain simplified LCA method limited to LCCO2 calculation for all kind of buildings such as detached houses and large-scale commercial buildings. This paper describes current situation on these projects of which the author has taken charge.

OUTLINE OF CASBEE FOR URBAN DEVELOPMENT (CASBEE-UD) CASBEE; Comprehensive assessment system for building environmental efficiency Part 5

Shuzo MURAKAMI, Nobuhaya YAMAGUCHI, Yasushi ASAMI, Toshiharu IKAGA, Shinichi KABURAGI, Akira MATSUKUMA, Tomohiro UCHIIKE, Takashi HASHIMOTO

AIJ Journal of Technology and Design (Architectural Institute of Japan) 13 ( 25 ) 191 - 196 2007.06

Research paper (scientific journal), Joint Work, Accepted, ISSN 1341-9463

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Report on the Third Joint Workshop of ILCAJ and JLCA: LCA of Urban and Infrastructure System

IKAGA Toshiharu, MATSUMOTO Toru

Journal of Life Cycle Assessment, Japan (The Institute of Life Cycle Assessment, Japan) 3 ( 3 ) 187 - 191 2007

Research paper (scientific journal), Joint Work, Accepted, ISSN 18802761

A study on a porous residential building model in hot and humid regions part 2 - reducing the cooling load by component-scale voids and the CO2 emission reduction effect of the building model

T Hirano, S Kato, S Murakami, T Ikaga, Y Shiraishi, H Uehara

BUILDING AND ENVIRONMENT (PERGAMON-ELSEVIER SCIENCE LTD) 41 ( 1 ) 33 - 44 2006.01

Research paper (scientific journal), Joint Work, Accepted, ISSN 0360-1323

The purpose of this paper is to show the effectiveness of porous residential buildings in hot and humid regions in the light of cooling load and CO2 emission reductions. Thermal and Airflow Network analysis and LCA analysis are used for these simulations. Two scales of voids, namely building-scale voids and component-scale voids are considered. In the previous paper (Hirano et at. Building and Environment, forthcoming), it was revealed that building-scale voids are substantially effective in terms of reducing the cooling load. This paper firstly focuses on the cooling load reduction effects of component-scale voids, then moves on to the CO2 emission reduction effects of both component- and building-scale voids. Additionally, other environmentally friendly techniques are examined in order to assess the feasibility of the Architectural Institute of Japan (AIJ) charter, which sets the target that new buildings should extend their service life up to 100 years as well as reduce Life-Cycle CO2 (LCCO2) emission by 30%. (c) 2005 Elsevier Ltd. All rights reserved.

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A study on a porous residential building model in hot and humid regions: Part 1 - the natural ventilation performance and the cooling load reduction effect of the building model

T Hirano, S Kato, S Murakami, T Ikaga, Y Shiraishi

BUILDING AND ENVIRONMENT (PERGAMON-ELSEVIER SCIENCE LTD) 41 ( 1 ) 21 - 32 2006.01

Research paper (scientific journal), Joint Work, Accepted, ISSN 0360-1323

This study targets environmental load reduction in hot and humid regions. It reveals the effects that porous residential buildings have on the natural ventilation performance and, consequently, the cooling load reduction. Two residential building models, namely a model with a void ratio of 0% and a model with a void ratio of 50%, are evaluated using computational fluid dynamics (CFD) analysis and thermal and airflow network analysis. The analysis on components of the heat load indicates that improvements in the natural ventilation performance would significantly reduce the cooling load. (c) 2005 Elsevier Ltd. All rights reserved.

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Report on the First Joint Workshop of ILCAJ and JLCA

IKAGA Toshiharu, AOE Taeko

Journal of Life Cycle Assessment, Japan (The Institute of Life Cycle Assessment, Japan) 2 ( 2 ) 195 - 198 2006

Research paper (scientific journal), Joint Work, Accepted, ISSN 18802761

Evaluation on Electrical System of Building Based on Comprehensive Assessment System for Building Environmental Efficiency

伊香賀俊治

The Journal of the Institute of Electrical Installation Engineers of Japan (The Institute of Electrical Installation Engineers of Japan) 26 ( 12 ) 883 - 886 2006

Research paper (scientific journal), Joint Work, Accepted, ISSN 09100350

LCCO_2 ASSESSMENT ON THERMAL INSULATION OF RESIDENTIAL BUILDINGS INCLUDING FLUOROCARBON LEAKAGE : Study on reduction of greenhouse gas from houses by thermal insulation

MIZUISHI Tadashi, MURAKAMI Shuzo, IKAGA Toshiharu

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 69 ( 579 ) 89 - 96 2004

Research paper (scientific journal), Joint Work, Accepted, ISSN 13480685

The first purpose of this study is to simulate the emission of life cycle greenhouse gas (GHG) including fluorocarbon leakage from thermal insulation of houses and comprehensively evaluate both the reduction of C0_2 emission by heating and cooling and the rise of GHG emission by fluorocarbon leakage. The results of the simulation are as follows; 1) Life cycle CO_2 emission by heating and cooling of 1999 standard is reduced by 50% than that of 1980 standard. 2) However, GHG emission including fluorocarbon leakage rises in some cases. The second purpose of this study is to forecast GHG emission by heating and cooling, manufacture of building materials and fluorocarbon leakage from all houses in Japan up to 2012. The results are as follows; 3) If the current situation continues, CO_2 emission by heating and cooling for the period 2008-2012 will rise by 9.9% compared to 1990 levels. 4) If thermal insulation of new housing is improved as rapidly as possible by 2010, it will rise by 9.1%, but however, GHG emission including fluorocarbon leakage will rise by 18.7%. 5) On the other hand, if measures for fluorocarbon leakage are taken, it could be reduced by 0.6%. 6) In addition to these measures, if thermal insulation of existing residential buildings is implemented, it could be reduced by 3.1%.

STUDY ON NON-ENERGY BENEFITS (NEB) BY AREA-WIDE ENERGY UTILIZATION

Ryota KUZUKI, Toshiharu IKAGA, Shuzo MURAKAMI

Journal of Environmental Engineering (Transactions of AIJ) (Architectural Institute of Japan) 75 ( 653 ) 645 - 652 2002.07

Research paper (scientific journal), Joint Work, Accepted, ISSN 1348-0685

In the building field, for the purpose of further energy saving and lower carbon intensity, area-wide energy utilization is expected to play an important role in Japan. But such projects require agreement among stakeholders belonging to the area, which is one of the major hurdles of the realization. This paper describes the promotion measures to motivate agreement among stakeholders as below; 1. Indicating the further improvement of the cost-benefit ratio (B/C) to be shared among stakeholders in consideration of a variety of non-energy benefit (NEB) 2. Identifying B/C for each stakeholder in consideration of the revert of each cost and benefit belonging to some specific stakeholders 3. Expression of the risk caused by the uncertainty of cost and benefit estimation in the early planning phases of projects, and seeking proper allocation of cost and benefit, depending on the difference of the risk preference among stakeholders The effectiveness of the concept above is verified through a case study based on an actual project.

Access to Document (DOI)

PROPOSAL TO PROMOTE SUSTAINABLE BUILDINGS

Sub Committee on Sustainable Buildings

AIJ journal of technology and design (Architectural Institute of Japan) 116 ( 1474 ) 163 - 168 2001.07

Research paper (scientific journal), Joint Work, Accepted, ISSN 1341-9463

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