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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