Takehide Soh

Takehide Soh (宋剛秀)
Associate Professor (Graduate School of Informatics, Nagoya University)
Research Interests
- Practice of Boolean Satisfiability (SAT)
- Practice of Constraint Programming (CP)
Banbara-Soh Laboratory

Combinatorial problems arise in scheduling sports matches, planning manufacturing processes, and assigning hospital shifts. Since trying every possible combination quickly becomes impractical, I study general-purpose software called solvers that can find solutions efficiently. My current focus is on constraint solvers based on constraint propagation, with the goal of making difficult real-world problems easier to solve.

News

On September 9, 2026, I will give a talk titled “Mechanisms of SAT Solvers and Applications to Constraint Solvers” at the 94th ORSJ Autumn Symposium. [Symposium] [Speakers]
At the XCSP3 Competition 2026, held in conjunction with FLoC 2026, KAT was recognized as a joint winner of the Main CSP track. [FLoC 2026 Olympiad] [Photos and diploma]

2025.12.01 Talk information

Publications and Statistics

Full list of publications are here.

Employment

2025 Aug. - present. Associate Professor, Graduate School of Informatics, Nagoya University
2022 Apr. - 2025 Jul. Associate Professor, Information Infrastructure and Digital Transformation Initiatives Headquaters, Kobe University
2019 Apr. - 2022 Mar. Associate Professor, Information Science and Technology Center, Kobe University
2017 Sep. - 2018 Sep. Visiting Researcher, Centre national de la recherche scientifique; CNRS, France
2012 Apr. - 2019 Mar. Assistant Professor, Information Science and Technology Center, Kobe University
2011 Oct. - 2012 Mar. Project Researcher, Transdisciplinary Research Integration Center (TRIC)
2010 Apr. - 2011 Sep. Research Fellow, Japan Society for the Promotion of Science (JSPS)
2008 Apr. - 2010 Sep. Research Assistant, National Institute of Informatics
2006 Apr. - 2008 Mar. work @ Information Systems Department, Suntory Limited

Education

2011 Sep. Ph.D., Dapartment of Informatics, The Graduate University for Advanced Studies (Sokendai)
2006 Mar. M.S. Engineering, Graduate School of Science and Technology, Kobe University
2004 Mar. B.S. Engineering, Department of Engineering, Kobe University
2002 Mar. Associate Degree, Nara National College of Technology

Invited Talk

2026 Sep. Mechanisms of SAT Solvers and Applications to Constraint Solvers
- The 94th ORSJ Autumn Symposium, “Expanding Mathematical Sciences,” Kyoto University. Speaker profile
2025 Dec. SAT Solvers and Constraint Solvers: Foundational Techniques and Recent Trends
- Symposium: Constraint Satisfaction, Search, Enumeration, and Optimization — Frontiers of Techniques for Finding Good “Answers”, The 134th Meeting of the Special Interest Group on Fundamental Problems in Artificial Intelligence (SIG-FPAI), Japanese Society for Artificial Intelligence, Keio University
2023 Sep. On SAT Solver and its Applications
- AT-1 Combinatorics and Information Theory, IEICE Society Conference, IEICE, Nagoya University.
2015 Dec. SAT Solver and its Application Development
- The 9th AI Tool Introduction Seminar, JSAI, National Institute of Informatics.

Award (Research)

2026 Aug. XCSP26 Main CSP joint winner🥇
2023 July. 10-year Test-of-Time Award, International Conference on Logic Programming (ICLP) 2023
2023 Aug. XCSP23 Main CSP Solver 2nd place🥈
2022 Aug. XCSP22 Main CSP Solver 2nd place🥈
2019 Aug. XCSP19 Main CSP Solver 2nd place🥈
2019 Aug. JSSST 7th Best Review Paper Award (2018)
2019 Aug. JSAI Annual Conference Award 2019 (33rd)
2018 Sep. Specially Selected Paper --- Journal of Information Processing, IPSJ
2018 Aug. XCSP18 Sequential CSP Solver 1st place🥇, Parallel CSP Solver 1st place🥇
2017 Mar. PPL 2017 Presentation Award
2015 Sep. 2015 Best Research Paper Award --- Japan Society for Software Science and Technology
2015 Aug. The 1st place at algorithm design contest of DA symposium 2015
2014 Nov. The 31st Annual Conference of JSSST, Takahashi Encouragement Award (2014)
2014 Aug. The 1st place at algorithm design contest of DA symposium 2014 / SWEST16
2010 Apr. The SOKENDAI President's Award.
2009 Sep. The 2009 JSAI Convention Award.

Award (Education)

2021 Oct. Kobe University Best Teacher Award for General Education, AY2021 Spring, Information Fundamentals (primary instructor)

Language

Japanese (Native), English (TOEIC 905)

Grant, Competitive Research Funds (as Principal Investigator)

2023/04 - 2027/03
- (PI) Speeding-up SAT-based Constraint Optimization Solvers
- JSPS Grants-in-Aid for Scientific Research (C), No. 23K11047
2023/04 - 2024/03
- (PI) Research on SAT-based Methods for Combinatorial Reconfiguration Problems
- 2023 NII Collaborative Research Grants
2020/04 - 2023/03
- (PI) Acceleration of SAT-based CSP Solvers using MDD Research Project
- JSPS Grants-in-Aid for Scientific Research (C), No. 20K11748
2019/04 - 2020/03
- (PI) Research and Development of a New SAT-based Parallel CSP Solver using Multiple Constraint Modelings and SAT Encodings
- 2019 NII Collaborative Research Grants
2019/08 - 2021/07
- (PI) Computing Attractors in Asynchronous Automata Networks using SAT Technology
- JSPS Bilateral Programs (Joint Research Projects) Joint Research Projects with FRANCE (MEAE-MESRI) ``SAKURA Program''
2016/04 - 2019/03
- (PI) High Performance SAT-based Constraint Programming System using Hybrid Encoding
- JSPS Grants-in-Aid for Young Scientists (B), No. 16K16036
2013/04 - 2016/03
- (PI) Research and Development of Constraint Programming Systems for Pathway Analysis
- JSPS Grants-in-Aid for Young Scientists (B), No. 25730042
2014/04 - 2015/03
- (PI) Research on High-performance Educational Timetabling Systems using SAT Technology
- 2014 NII Collaborative Research Grants
2013/04 - 2014/03
- (PI) Research on High-performance and Hi-level Constraint ASP Solvers Using Incremental Solving
- 2013 NII Collaborative Research Grants
2011/11 - 2012/03
- (PI) Knowledge Discovery on Global Regulation Networks Based on Inference with Causal Relations
- The 2nd Transdisciplinary Seeds Research
2010/04 - 2012/03
- (PI) Solving Constraint Satisfaction Problem via SAT Encoding and its Application to Systems Biology
- JSPS Research grant (Grant-in-Aid for JSPS Fellows) for Doctoral Course Students (DC2)

Grant, Competitive Research Funds (KAKENHI, as Co-Investigator)

2026/04 - 2030/03
- (Co-I) Realizing a Parallel Distributed Foundation Supporting Determinism and Incrementality of SAT-based Constraint Solvers
- JSPS Grants-in-Aid for Scientific Research (B), No. 26K02983, PI: Hidetomo Nabeshima
2025/04 - 2028/03
- (Co-I) General-purpose Methods for Combinatorial Reconfiguration Problems based on Answer Set Programming and Extensions to Transition Optimization
- JSPS Grants-in-Aid for Scientific Research (B), No. 25K03097, PI: Mutsunori Banbara
2024/04 - 2028/03
- (Co-I) Theory of Combinatorial Reconfiguration Focusing on the Shape of Solution Spaces: Refining Complexity Analysis and New Solver Techniques
- JSPS Grants-in-Aid for Scientific Research (A), No. 24H00686, PI: Takehiro Ito
2022/04 - 2025/03
- (Co-I) Research and Development of New SAT Solving Technologies for Constraint Satisfaction Problems
- JSPS Grants-in-Aid for Scientific Research (C), No. 22K11973, PI: Naoyuki Tamura
2021/04 - 2024/03
- (Co-I) Research and Development on SAT-based Integration of Systematic and Stochastic Search
- JSPS Grants-in-Aid for Scientific Research (C), No. 21K11828, PI: Mutsunori Banbara
2020/10 - 2023/03
- (Co-I) Expanding Combinatorial Reconfiguration through Engineering Approaches: From Power Distribution Switching toward General-purpose Solvers
- JSPS Grant-in-Aid for Transformative Research Areas (B), No. 20H05794, PI: Jun Kawahara
2018/04 - 2021/03
- (Co-I) Research and Development of Multi-objective Optimization Solvers based on Advanced Knowledge Representation and Reasoning Technologies
- JSPS Grants-in-Aid for Scientific Research (C), No. 18K11242, PI: Mutsunori Banbara
2016/04 - 2019/03
- (Co-I) Research and Development of a New Constraint Programming System based on SAT
- JSPS Grants-in-Aid for Scientific Research (B), No. 16H02803, PI: Naoyuki Tamura
2015/04 - 2018/03
- (Co-I) Research and Development on Constraint Answer Set Programming using SAT Encoding
- JSPS Grants-in-Aid for Scientific Research (C), No. 15K00099, PI: Mutsunori Banbara
2012/04 - 2015/03
- (Co-I) Realization of High-performance and Flexible Constraint Programming Systems using Propositional Inference Technologies
- JSPS Grants-in-Aid for Scientific Research (B), No. 24300007, PI: Naoyuki Tamura

Teaching Experience

Information Fundamentals (Kobe University, Undergraduate)
Language Engineering (Kobe University, Undergraduate)
Software Engineering (Kobe University, Undergraduate)
Programming Language Theory and Practice: First Half of Exercises (Kobe University, Undergraduate)
Advanced Topics in Programming Languages (Kobe University, Graduate School)
Special Topics in Software Science 2 (Kobe University, Graduate School)
Knowledge Representation and Processing (University of Potsdam, Germany, Undergraduate/Graduate)
- Date and Time: Lecture on July 11, 2014, from 12:15 to 13:15
- Title: Incremental SAT-based Method with Native Boolean Cardinality Handling for the Hamiltonian Cycle Problem
Introduction to the Scala Programming Language (University of Altois, France, Graduate School)

Professional/Academic Service (International)

International Joint Conferences on Artificial Intelligence (IJCAI)
- PC member: 2017, 2020, 2021, 2022, 2023, 2024
Annual AAAI Conference on Artificial Intelligence (AAAI)
- PC member: 2022
International Conference on Theory and Applications of Satisfiability Testing (SAT)
- PC member: 2016, 2018, 2019, 2021, 2022
International Symposium on Combinatorial Search (SoCS)
- PC member: 2021, 2022, 2023, 2024
International Workshop of Pragmatics of SAT (PoS)
- PC member: 2015, 2017, 2019
Doctoral Consortium of International Conference on Logic Programming
- PC member: 2014, 2015, 2016, 2017

Professional/Academic Service (Domestic)

2019 Apr. - present: Editorial Board Member, Japan Society for Software Science and Technology (JSSST)
2019 Apr. - 2023 Mar.
- Steering Committee Member, IPSJ Special Interest Group on Programming
- Editorial Board Member, IPSJ Transactions on Programming
Workshop on Programming and Programming Languages (PPL)
- Program Committee Member: 2015, 2017, 2022
JSAI Annual Conference Organized Sessions
- Theory, Implementation, and Applications of SAT Technology
  - Organizer: 2013, 2014, 2015, 2016
- AI and Constraint Programming
  - Organizer: 2021, 2022, 2023, 2024