KEIO RESEARCHERS INFORMATION SYSTEM

Career 【 Display / hide 】

Career 【 Display / hide 】

• 1989.04

  -

  1993.03

  Tokyo Institute of Technology, Research Assistant

• 1993.04

  -

  1994.09

  University of Electro-Communications, Lecturer

• 1994.10

  -

  1999.03

  University of Electro-Communications, Associate Professor

• 1999.04

  -

  2000.03

  University of Electro-Communications, Associate Professor (concurrent)

• 1999.04

  -

  2004.09

  Kyoto University, Associate Professor

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Academic Background 【 Display / hide 】

Academic Background 【 Display / hide 】

• 1984.03

  Tokyo Institute of Technology, Faculty of Science, Department of Information Sciences

  University, Graduated

• 1986.03

  Tokyo Institute of Technology, School of Science, Department of Infotmation Sciences

  Graduate School, Completed, Master's course

• 1989.03

  Tokyo Institute of Technology, School of Science, Department of Infotmation Sciences

  Graduate School, Completed, Doctoral course

Academic Degrees 【 Display / hide 】

Academic Degrees 【 Display / hide 】

• Doctor of Science, Tokyo Institute of Technology, Dissertation, 1989.03

  Local Deformations in Oriented Matroids

Research Areas 【 Display / hide 】

Research Areas 【 Display / hide 】

• Natural Science / Basic mathematics (General Mathematics (includes Probability Theory/Statistical Mathematics))

• Natural Science / Applied mathematics and statistics (General Mathematics (includes Probability Theory/Statistical Mathematics))

• Informatics / Mathematical informatics

Research Keywords 【 Display / hide 】

Research Keywords 【 Display / hide 】

• mathematical optimization

• combinatorial optimization

• discrete optimization

• discrete convex analysis

• Algorithms

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Books 【 Display / hide 】

Books 【 Display / hide 】

• 計算による最適化入門 (in Japanese)

  Fukuda, Komei; Tamura, Akihisa, Kyoritsu Shuppan, 2022.07

• モデリングー広い視野を求めてー (in Japanese)

  Tamura, Akihisa, Kindaikagku, 2015.03

  Scope: 137-148

• 離散凸解析とゲーム理論 (in Japanese)

  Tamura, Akihisa, Asakura Publishing, 2009.11

• 応用数理計画ハンドブック (in Japanese)

  Kubo, Mikio; Tamura, Akihisa; Matsui, Tomomi, Asakura Publishing, 2002.04

• 最適化法 (in Japanese)

  Tamura, Akihisa; Matsumura, Masakazu, Kyoritsu Shuppan, 2002.04

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Papers 【 Display / hide 】

Papers 【 Display / hide 】

• Two proofs of a structural theorem of decreasing minimization on integrally convex sets

  Murota, K. and Tamura, A.

  Japan Journa of Industirial and Applied Mathematics  2025.06

  Research paper (scientific journal), Joint Work, Accepted,  ISSN  09167005

  　View Summary

  This paper gives two different proofs to a structural theorem of decreasing minimization (lexicographic optimization) on integrally convex sets. The theorem states that the set of decreasingly minimal elements of an integrally convex set can be represented as the intersection of a unit discrete cube and a face of the convex hull of the given integrally convex set. The first proof resorts to the Fenchel-type duality theorem in discrete convex analysis and the second is more elementary using Farkas’ lemma.

  • Access to Document (DOI)

• Shapley–Folkman-type theorem for integrally convex sets

  Murota, K. and Tamura, A.

  Discrete Applied Mathematics 360   42 - 50 2025

  Research paper (scientific journal), Joint Work, Accepted,  ISSN  0166218X

  　View Summary

  The Shapley–Folkman theorem is a statement about the Minkowski sum of (non-convex) sets, expressing the closeness of the Minkowski sum to convexity in a quantitative manner. This paper establishes similar theorems for integrally convex sets, M♮-convex sets, and L♮-convex sets, which are major classes of discrete convex sets in discrete convex analysis.

  • Access to Document (DOI)

• Note on Minkowski Summation and Unimodularity in Discrete Convex Analysis

  Murota, K. and Tamura, A.

  Journal of the Operations Research Society of Japan (The Operations Research Society of Japan)  67 ( 4 ) 126 - 134 2024.10

  Research paper (scientific journal), Joint Work, Accepted,  ISSN  04534514

  　View Summary

  This short note gives an elementary alternative proof for a theorem of Danilov and Koshevoy on Minkowski summation and unimodularity in discrete convex analysis. It is intended to disseminate this fundamental theorem and make its proof accessible to researchers in optimization and operations research.

  • Access to Document (DOI)

• Decomposition of an integrally convex set into a Minkowski sum of bounded and conic integrally convex sets

  Murota, K. and Tamura, A.

  Japan Journa of Industirial and Applied Mathematics 41 ( 2 ) 987 - 1011 2024.05

  Research paper (scientific journal), Joint Work, Accepted,  ISSN  09167005

  　View Summary

  Every polyhedron can be decomposed into a Minkowski sum (or vector sum) of a bounded polyhedron and a polyhedral cone. This paper establishes similar statements for some classes of discrete sets in discrete convex analysis, such as integrally convex sets, L ♮ -convex sets, and M ♮ -convex sets.

  • Access to Document (DOI)

• A fair and truthful mechanism with limited subsidy

  Goko H., Igarashi A., Kawase Y., Makino K., Sumita H., Tamura, A.., Yokoi Y., Yokoo M.

  Games and Economic Behavior 144   49 - 70 2024.03

  Research paper (scientific journal), Joint Work, Accepted,  ISSN  08998256

  　View Summary

  The notion of envy-freeness is a natural and intuitive fairness requirement in resource allocation. With indivisible goods, such fair allocations are not guaranteed to exist. Classical works have avoided this issue by introducing an additional divisible resource, i.e., money. In this paper, we aim to design a truthful allocation mechanism of indivisible goods to achieve fairness and efficiency criteria with a limited amount of subsidy. Following the work of Halpern and Shah, our central question is as follows: to what extent do we need to rely on the power of money to accomplish these objectives? We show that, when agents have matroidal valuations, there is a truthful allocation mechanism that achieves envy-freeness and utilitarian optimality by subsidizing each agent with at most 1, the maximum marginal contribution of each item for each agent. The design of the mechanism rests crucially on the underlying matroidal M-convexity of the Lorenz dominating allocations.

  • Access to Document (DOI)

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Papers, etc., Registered in KOARA 【 Display / hide 】

Papers, etc., Registered in KOARA 【 Display / hide 】

• Discrete allocation problems with hard constraints : study with the aid of discrete convex analysis

  Tamura, Akihisa

  科学研究費補助金研究成果報告書 2021

• Development of extremal graph theory for sparse graphs

  Tamura, Akihisa

  科学研究費補助金研究成果報告書 2021

Reviews, Commentaries, etc. 【 Display / hide 】

Reviews, Commentaries, etc. 【 Display / hide 】

• 離散凸解析とゲーム理論

  田村 明久

  数学セミナー (日本評論社)  53 ( 10 ) 20 - 24 2014.10

  Article, review, commentary, editorial, etc. (trade magazine, newspaper, online media), Single Work

• 安定結婚からサプライチェーンネットワークの安定性へ

  田村 明久

  オペレーションズ・リサーチ (日本オペレーションズ・リサーチ学会)  58 ( 6 ) 325 - 331 2013.06

  Article, review, commentary, editorial, etc. (scientific journal), Single Work

• １２群「電子情報通信基礎」２編「離散数学」6章「数理計画法」

  田村 明久

  知識ベース　地の森（電子媒体） (電子情報通信学会)   2009

  Article, review, commentary, editorial, etc. (trade magazine, newspaper, online media), Single Work

• Stable Marriage and Discrete Convex Analysis

  Tamura, A.

  Encyclopedia of Algorithms (Springer)     880 - 883 2008

  Article, review, commentary, editorial, etc. (other), Single Work

• マッチングモデル

  田村 明久

  オペレーションズ・リサーチ (日本オペレーションズ・リサーチ学会)  50 ( 4 ) 247 - 250 2005.04

  Article, review, commentary, editorial, etc. (scientific journal), Single Work

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Presentations 【 Display / hide 】

Presentations 【 Display / hide 】

• A Structural Theorem of Decreasing Minimization on Integrally Convex Sets

  K. Murota*, A. Tamura

  The 13th Hungarian-Japanese Symposium on Discrete Mathematics and Its Applications (HJ2025) (Institute of Scinece Tokyo ) , 

  2025.05

  , 

  Oral presentation (general)

• 離散最適化のメカニズムデザインへの適用

  田村明久*

  FIT2024 (広島工業大学) , 

  2024.09

  , 

  Public lecture, seminar, tutorial, course, or other speech

• 私の研究ー過去，現在，未来

  田村明久

  最適化の理論とアルゴリズム:未来を担う若手研究者の集い 2024 (筑波大学) , 

  2024.05

  , 

  Oral presentation (invited, special), 日本オペレーションズ・リサーチ学会 最適化の理論とアルゴリズム部会

• ネットワーク適応型M♮凸関数の紹介

  田村明久*

  ERATO小島メカニズムデザインプロジェクトキックオフミーティング (東京大学) , 

  2024.03

  , 

  ERATO小島メカニズムデザインプロジェクト

• 離散Minkowski和とユニモジュラ行列の関係の初等的証明

  室田一雄, 田村明久*

  日本オペレーションズリサーチ学会春季研究発表会 (筑波大学) , 

  2024.03

  , 

  Oral presentation (general), 日本オペレーションズリサーチ学会

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Research Projects of Competitive Funds, etc. 【 Display / hide 】

Research Projects of Competitive Funds, etc. 【 Display / hide 】

• Creation of Incentive Design Science

  2020.04

  -

  2023.03

  Grants-in-Aid for Scientific Research, Yokoo Makoto, Grant-in-Aid for Scientific Research (A), Research grant, No Setting

  　View Summary

  In this project, four research groups, i.e., two-sided matching, auction, AI/optimization, behavioral/experimental economics, conducted research in a close collaboration. Within the project period, we have published 40 papers, performed 45 presentations (including 13 invited talks). In particular, we conducted research on following topics: constrained two-sided matching, auctions on social networks, distributed constraint optimization, max satisfiablity problems against adversary, new group decision making procedure called majority judgment. For these topics, we have obtained various research results, which are published in top international conferences and international journals.

• Establishing a Practical Theory of Market Design

  2017.04

  -

  2020.03

  Kyushu University, Yokoo Makoto, Grant-in-Aid for Scientific Research (A), Research grant, Coinvestigator(s)

  　View Summary

  In this project, we conducted theoretical researches on general market design. We published 32 articles in international journals and 33 papers from proceedings of international conferences, and 18 invited talks. We also conducted 14 international joint researches in total.
  During the project, PI and Co-PIs have received several community/conference awards, including the Commendation for Science and Technology by MEXT.

• Discrete Allocation Problems with hard constraints: Study with the aid of discrete convex analysis

  2016.04

  -

  2020.03

  MEXT,JSPS, Grant-in-Aid for Scientific Research, Tamura Akihisa, Grant-in-Aid for Scientific Research (C), Research grant, Principal investigator

  　View Summary

  The aims of this research are to deeply study discrete allocation problems with hard constraints by using discrete convex analysis, and to apply theoretical results to problems in the real world. We established five research themes and obtain theoretical results for each theme. On feedback to problems in the real world, we developed software of our two proposed algorithms which have been used to solve the allocation problem of students to departments in our affiliation.

• Establishing Theory of Resource Allocation Mechanism Design for Sustainable Development

  2012.05

  -

  2017.03

  Kyushu University, Yokoo Makoto, KOJIMA Fuhito, OBARA Ichiro, Grant-in-Aid for Scientific Research (S), Research grant, Coinvestigator(s)

  　View Summary

  How to allocate precious resources becomes critical due to various pressing social issues, including energy, environmental, and aging population issues. The goal of this project is developing the theory of resource allocation mechanism design, which aims to make desirable decisions considering economic, social, and environmental needs when multiple agents exist, by synthesizing/extending technologies from computer science and micro economics. More specifically, we developed design, analytic, and representation technologies for resource allocation. In particular, we made notable contributions on mechanism design for constrained two-sided matching, equilibrium analysis for repeated games in noisy environments, and concise and efficient representations for coalitional games. The summary of publications of this project is as follows: refereed international conferences 87, international journals 74, domestic journals 11, research monographs 8, textbooks 4, invited talks 40.

• Deep Studies on Allocation Problems with Discrete Structures

  2012.04

  -

  2015.03

  MEXT,JSPS, Grant-in-Aid for Scientific Research, Tamura Akihisa, Fleiner Tamas, Grant-in-Aid for Scientific Research (B), Research grant, Principal investigator

  　View Summary

  Discrete allocation problems (i.e., allocation of students to departments, allocation of residents to hospitals) are important practical problems. The aim of the project is to generalize the stable matching model by using discrete structures such as graphs and discrete convex analysis, and to analyze developed models.
  We develop a new mechanism for a discrete allocation problem with distributional constraints, and propose and analyze new generalizations of the stable matching model to directed networks, and so on. These results are summarized as six papers published in academic journals, two submitted papers, and two papers during preparations.

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Awards 【 Display / hide 】

Awards 【 Display / hide 】

• Achievement Award, The Operations Research Society of Japan

  Akihisa Tamura, 2024.03, The Operations Research Society of Japan

  Type of Award： Honored in official journal of a scientific society, scientific journal

• Case Study Award, The Operations Research Society of Japan

  Takashi Akahori, Yosuke Sekiguchi, Akihisa Tamura, 2018.09, The Operations Research Society of Japan, The Students/Departments Allocation Problem with Group Constraints — An Application of Discrete Convex Analysis

  Type of Award： Honored in official journal of a scientific society, scientific journal

  　View Description

  TORSJ Vol. 60 (2017) に掲載された当該論文が2017年発行のJORSJ/TORSJの中で最も優れた事例研究論文と認められたため．

• Research Award, The Operations Research Society of Japan

  Akiyoshi Shioura, Akihisa Tamura, 2016.09, The Operations Research Society of Japan, Gross Substitutes Condition and Discrete Concavity for Multi-Unit Valuations: A survey

  Type of Award： Honored in official journal of a scientific society, scientific journal

  　View Description

  JORSJ Vol. 58 No. 1 (2015) に掲載された当該論文が2015年発行のJORSJ/TORSJの中で最も優れた論文と認められたため．

• Best Paper of the Year, The Operations Research Society of Japan

  Akihisa Tamura, 1998.05, The Operations Research Society of Japan, The Generalized Stable Set Problem for Perfect Bidirected Graphs

  Type of Award： Honored in official journal of a scientific society, scientific journal

Courses Taught 【 Display / hide 】

Courses Taught 【 Display / hide 】

• TOPICS IN LIFE INSURANCE MATHEMATICS

  2025

• MATHEMATICS 2B

  2025

• MATHEMATICS 2A

  2025

• MATHEMATICAL OPTIMIZATION

  2025

• INTRODUCTION TO LIFE INSURANCE

  2025

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Courses Previously Taught 【 Display / hide 】

Courses Previously Taught 【 Display / hide 】

• MATHEMATICS 2A

  Keio University

  2018.04

  -

  2019.03

  , 

  Spring Semester, Undergraduate (specialized), Lecture, Within own ｆaculty, 1h, 96people

• MATHEMATICS 2B

  Keio University

  2018.04

  -

  2019.03

  , 

  Autumn Semester, Undergraduate (specialized), Lecture, Within own ｆaculty, 1h, 138people

• COMPUTER SCIENCE & LABORATORY

  Keio University

  2018.04

  -

  2019.03

  , 

  Autumn Semester, Undergraduate (specialized), Lecture, Within own ｆaculty, 1h, 59people

• MATHEMATICAL PROGRAMMING

  Keio University

  2018.04

  -

  2019.03

  , 

  Autumn Semester, Undergraduate (specialized), Lecture, Within own ｆaculty, 1h, 42people

• BACHELOR'S THESIS

  Keio University

  2018.04

  -

  2019.03

  , 

  Full academic year, Undergraduate (specialized), Within own ｆaculty, 2h, 4people

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Social Activities 【 Display / hide 】

Social Activities 【 Display / hide 】

• 慶應義塾大学保険フォーラム「アクチュアリーとデータ解析〔II〕極端な事象(主に地震)と保険」

  慶應義塾大学　OLIS-プルデンシャル・ジブラルタ生命保険寄附講座,  (慶應義塾大学日吉キャンパス)

  , 

  2018.03

  　View Summary

  生命保険に関する事柄を一般向けに広く紹介することを目的とした寄附講座開催のフォーラム．

• 慶應義塾大学保険フォーラム「アクチュアリーとデータ解析〔I〕新たな時代の予感」

  慶應義塾大学　OLIS-プルデンシャル・ジブラルタ生命保険寄附講座,  (慶應義塾大学日吉キャンパス)

  , 

  2017.03

  　View Summary

  生命保険に関する事柄を一般向けに広く紹介することを目的とした寄附講座開催のフォーラム．

• 慶應義塾大学保険フォーラム「保険と予測」

  慶應義塾大学　OLIS-プルデンシャル・ジブラルタ生命保険寄附講座,  (慶應義塾大学日吉キャンパス)

  , 

  2016.01

  　View Summary

  生命保険に関する事柄を一般向けに広く紹介することを目的とした寄附講座開催のフォーラム．

• 慶應義塾大学保険フォーラム「ダブル・メジャーの時代〜チャールズ・アイブスに学ぶ保険ビジネスと音楽〜」

  慶應義塾大学　OLIS-プルデンシャル・ジブラルタ生命保険寄附講座,  (慶應義塾大学日吉キャンパス)

  , 

  2015.01

  　View Summary

  生命保険に関する事柄を一般向けに広く紹介することを目的とした寄附講座開催のフォーラム．

• 慶應義塾大学保険フォーラム「就活 金融の世界を垣間見る」

  慶應義塾大学　OLIS-プルデンシャル・ジブラルタ生命保険寄附講座,  (慶應義塾大学日吉キャンパス)

  , 

  2013.12

  　View Summary

  生命保険に関する事柄を一般向けに広く紹介することを目的とした寄附講座開催のフォーラム．

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Memberships in Academic Societies 【 Display / hide 】

Memberships in Academic Societies 【 Display / hide 】

• The Operations Research Society of Japan, 

  1985

  -

  Present

• Mathematical Optimization Society, 

  2010

  -

  Present

• The Japan Society for Industrial and Applied Mathematics, 

  1996

  -

  Present

• Information Processing Society of Japan, 

  2004

  -

  2019.03

• Mathematical Programming Society, 

  1990

  -

  2010

Committee Experiences 【 Display / hide 】

Committee Experiences 【 Display / hide 】

• 2003.03

  -

  Present

  Fellow, The Operations Research Society of Japan

• 2019.01

  -

  Present

  Editor, Japan Journal of Industrial and Applied Mathematics

• 2015.05

  -

  Present

  Associate Editor, Journal of Mechansim and Institution Design

• 2024.04

  -

  2026.04

  Member of Delogation, The Operations Research Society of Japan

• 2021.04

  -

  2023.04

  副会長, 日本オペレーションズ・リサーチ学会

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