Keiya Sakabe’s Homepage

Last updated: Nov. 5, 2024
[日本語]

Keiya Sakabe

Master’s Student at Mathematical Informatics 3rd Laboratory, Graduate School of Information Science and Technology, The University of Tokyo, Japan

Supervisor: Takayasu Matsuo

Email: ksakabe (at) g.ecc.u-tokyo.ac.jp

Education

• Apr. 2023 – Now: Master’s Student, Graduate School of Information Science and Technology, The University of Tokyo, Japan

• Mar. 2023: Bachelor of Engineering. Department of Mathematical Engineering and Information Physics, The University of Tokyo, Japan

• Mar. 2018: Graduated from Kaiyo Academy, Japan

Thesis

Bachelor’s Thesis: 非有界な凸関数に対する最急降下法と行列スケーリングへの応用 (Gradient Descent for Unbounded Convex Functions and Its Application to Matrix Scaling)
Supervised by Hiroshi Hirai
In Japanese

Publications

• Finding Hall blockers by matrix scaling.
  Koyo Hayashi, Hiroshi Hirai, Keiya Sakabe.
  [arXiv]
  Mathematics of Operations Research, to appear.

• Gradient descent for unbounded convex functions on Hadamard manifolds and its applications to scaling problems.
  Hiroshi Hirai, Keiya Sakabe.
  [arXiv]
  Proceedings of the 2024 IEEE 65th Annual Symposium on Foundations of Computer Science (FOCS 2024), pp. 2387–2402.

Talks in English

• Gradient descent for unbounded convex functions on Hadamard manifolds and its applications to scaling problems.
  Oct. 2024: 65th IEEE Symposium on Foundations of Computer Science (FOCS) 2024, Chicago, IL, USA

• Steepest descent algorithm for unbounded convex functions.
  Dec. 2024: Quantum Information Colloquium, Bochum, Germany

Teaching Assistant

• Oct. 2023 – Mar. 2024: 数学1D (Mathematics 1-D), The University of Tokyo
  Instructor: Motohiko Ezawa

• Apr. 2023 – Sep. 2024: 数理情報工学実験第二 (Mathematical Informatics Engineering Laboratory 2), The University of Tokyo
  Instructor: Shun Sato

Awards

• 優秀発表賞 (Good Presentation Award). 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, RAOTA, May. 2024, Tsukuba, Japan

• 優秀発表賞 (Good Presentation Award). 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 2023, RAOTA, May. 2023, Tsukuba, Japan

• 工学部長賞 (Dean’s Award). Mar. 2023, Faculty of Engineering, The University of Tokyo, Japan

Competitions

• The 29th International Olympiad in Informatics: Silver Medal. Aug. 2017, Tehran, Iran
• The 49th International Chemistry Olympiad: Gold Medal. Jul. 2017, Nakhon Pathom, Thailand
• The 10th International Earth Science Olympiad: Gold Medal. Aug. 2016, Mie, Japan
• The 48th International Chemistry Olympiad: Gold Medal. Jul. 2016, Tbilisi, Georgia

Others

• Internship at Preferred Networks, Inc., Jul. 2023 – Sep. 2023. [Tech Blog in Japanese]

• Volunteering at science camps for high school students. [2019] [2021] [2023]