I am an assistant professor at Faculty of Engineering, Tokyo University of Agriculture and Technology.
7th Building, Room 506, 2-24-16 Nakacho, Koganei, Tokyo 184-8588, Japan.
Email: mizutani [at] go.tuat.ac.jpmizutani [at] math.keio.ac.jp ,ryuhei_mizutani [at] mist.i.u-tokyo.ac.jp
Research Interests
Combinatorial Optimization, Discrete Structures, Matroid Theory, Graph Theory, Game Theory.
C.V.
- Apr. 2026–present: Assistant Professor, Faculty of Engineering, Tokyo University of Agriculture and Technology.
- Apr. 2025–Mar. 2026: Project Researcher, Faculty of Science and Technology, Keio University.
- Mar. 2025: Ph.D. (Information Science and Technology), Department of Mathematical Informatics, Graduate School of Information Science and Technology, The University of Tokyo.
- Mar. 2022: M.S. (Information Science and Technology), Department of Mathematical Informatics, Graduate School of Information Science and Technology, The University of Tokyo.
- Mar. 2020: B.E., Department of Mathematical Engineering and Information Physics, School of Engineering, The University of Tokyo.
Refereed Journals and Conferences
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Ryuhei Mizutani, Yuki Yoshida.
Weakly Polynomial-Time Algorithms to Minimize 2/3-Submodular Functions.
Mathematical Programming Series B, 216:1–2 (2026), pp. 709–756. Journal
Proceedings of the 25th Conference on Integer Programming and Combinatorial Optimization (IPCO 2024), pp. 323–336. Conference (Previous title: Polynomial Algorithms to Minimize 2/3-Submodular Functions) -
Ryoga Mahara, Ryuhei Mizutani, Taihei Oki, Tomohiko Yokoyama.
Position Fair Mechanisms Allocating Indivisible Goods.
Proceedings of the 40th Annual AAAI Conference on Artificial Intelligence (AAAI 2026), pp. 17137–17144. Conference arXiv -
Ryuhei Mizutani.
Supermodular Extension of Vizing’s Edge-Coloring Theorem.
SIAM Journal on Discrete Mathematics, 39:4 (2025), pp. 2275–2295. Journal arXiv -
Dániel Garamvölgyi, Ryuhei Mizutani, Taihei Oki, Tamás Schwarcz, Yutaro Yamaguchi.
Towards the Proximity Conjecture on Group-Labeled Matroids.
Proceedings of the 52nd EATCS International Colloquium on Automata, Languages, and Programming (ICALP 2025), pp. 85:1–85:17. Conference arXiv -
Florian Hörsch, András Imolay, Ryuhei Mizutani, Taihei Oki, Tamás Schwarcz.
Problems on Group-Labeled Matroid Bases.
Proceedings of the 51st EATCS International Colloquium on Automata, Languages, and Programming (ICALP 2024), pp. 86:1–86:20. Conference arXiv -
Hiroshi Hirai, Ryuhei Mizutani.
Minimum 0-Extension Problems on Directed Metrics.
Discrete Optimization, 40 (2021), 25 pages. Journal arXiv
Proceedings of the 45th International Symposium on Mathematical Foundations of Computer Science (MFCS 2020), pp. 46:1–46:13. Conference
Preprints
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Satoru Fujishige, Ryuhei Mizutani.
A Note on Ordinal Submodularity.
arXiv preprints, arXiv:2602.16203, 2026. arXiv -
Ryuhei Mizutani.
Minimizing Submodular Functions over Hierarchical Families.
arXiv preprints, arXiv:2601.14805, 2026. arXiv -
Ryuhei Mizutani.
An Approximation Algorithm for Monotone Submodular Cost Allocation.
arXiv preprints, arXiv:2511.00470, 2025. arXiv -
Ryuhei Mizutani.
A Polynomial Algorithm for Minimizing \( k \)-Distant Submodular Functions.
arXiv preprints, arXiv:2407.05127, 2024. arXiv
International Talks
- Ryuhei Mizutani.
A Polynomial Algorithm for Minimizing \( k \)-Distant Submodular Functions.
The 13th Hungarian-Japanese Symposium on Discrete Mathematics and Its Applications, Tokyo, Japan, May 2025. - Ryuhei Mizutani, Yuki Yoshida.
Polynomial Algorithms to Minimize 2/3-Submodular Functions.
The 25th Conference on Integer Programming and Combinatorial Optimization (IPCO 2024), Wrocław, Poland, July 2024. - Ryuhei Mizutani.
Supermodular Extension of Vizing’s Edge-Coloring Theorem.
SIAM Conference on Optimization (OP23), Seattle, U.S., June 2023. - Ryuhei Mizutani.
Supermodular Extension of Vizing’s Edge-Coloring Theorem.
The 12th Japanese-Hungarian Symposium on Discrete Mathematics and Its Applications, Budapest, Hungary, March 2023. - Hiroshi Hirai and Ryuhei Mizutani.
Minimum 0-Extension Problems on Directed Metrics.
Mathematical Foundations of Computer Science (MFCS 2020), Prague, Czech Republic, August 2020.