Zhengyang Bai -- Homepage

Postdoctoral Researcher at RIKEN

Dr. Zhengyang Bai

・High Performance Artificial Intelligence Systems Research Team
・Learning Optimization Platform Development Unit, AI for Science Platform Division
RIKEN Center for Computational Science

Research interests: High Performance Computing, Artificial Intelligence and Programming Languages.

Current focus: Acceleration using Ray Tracing (RT) cores.

Work Experience

Postdoctoral Researcher @ RIKEN

Contract, May 2023 -- Present, Tokyo.

・High Performance Artificial Intelligence Systems Research Team

・Learning Optimization Platform Development Unit, AI for Science Platform Division

RIKEN Center for Computational Science

Internship Student

Intership, Mar & Aug 2021, Online.

Outsourcing Partner @ Yahoo! Japan

Part-time, Apr 2022 -- Mar 2023, Osaka.

Research Assistant @ Kyoto University

Part-time, Nov 2019 -- Mar 2023, Kyoto.

Kyoto University Graduate Division Fellow

Part-time, Dec 2021 -- Mar 2022, Kyoto.

Teaching Assistant

Part-time, Apr 2018 -- Jul 2020, Kyoto.

System Engineer @ Fujitsu Marketing Ltd.

Contract, Oct 2015 -- Mar 2016, Tokyo.

Overseas Internship Program Participant

Internship, Aug 2014 -- Nov 2014, Tokyo.

Android Engineer (intern) @ Teambition

Internship, Dec 2014 -- Feb 2015, Shanghai.

Education

Doctor of Informatics, Kyoto University

Apr 2019 -- Mar 2023, Kyoto.

Department: Department of System Science, Graduate School of Informatics

Laboratory: Supercomputing Laboratory (Nakashima & Fukazawa Lab.)

Supervisor: Prof. Keiichiro Fukazawa

Thesis: Research on Parallel Hierarchical Matrix Construction

Master of Informatics, Kyoto University

Apr 2017 -- Mar 2019, Kyoto.

Department: Department of System Science, Graduate School of Informatics

Laboratory: Supercomputing Laboratory (Nakashima & Fukazawa Lab.)

Supervisor: Prof. Hiroshi Nakashima

Thesis: Implementation of Partitioning of Hierarchical Matrices using Task Parallel Languages

Bachelor of Engineering, East China Normal University

Sep 2011 -- Jun 2015, Shanghai.

Department: Software Engineering Institute

Supervisor: Prof. Liangyu Chen

Thesis: Reverse Analysis for Java Class by ASM (in Chinese)

Publication Lists

Peer-Reviewed Papers

Tourist Attractions Recommendation by Using Enhanced Location Knowledge Graph, Jing Xu, Zhengyang Bai, Qiang Ma, IEEE Access, vol. 13, pp. 168463-168477, Sep 2025. link
Implementation of Hybrid CPU-GPU Programs in a Backtracking-based Load Balancing Framework, Jing Xu, Tasuku Hiraishi, Zhengyang Bai, Keiichiro Fukazawa, Masahiro Yasugi, Journal of Information Processing, Vol. 33(2025), pp. 494--506, Aug 2025. link
User-experience Oriented POI Recommendation with Pseudo Rating, Kun Yi, Ryu Yamagishi, Jiyi Li, Taishan Li, Zhengyang Bai, Qiang Ma, Multimedia Tools and Applications (2024), Jun 2024. link
U-KyotoTrip: A Travel Planning System for User Experience Oriented Trips, Kun Yi, Takeyuki Maekawa, Yuntao Kong, Zhengyang Bai, Xisha Jin, Qiang Ma, Information and Communication Technologies in Tourism 2024, pp. 339--352, Izumir, Turkey, Jan 2024. link
An Empirical User Study on Congestion-aware Route Recommendation, Kun Yi, Xisha Jin, Zhengyang Bai, Yuntao Kong, Qiang Ma, Information and Communication Technologies in Tourism 2024, pp. 325--338, Izumir, Turkey, Jan 2024. link
Tourist Attractions Prediction with Enhanced Location Knowledge Graph, Jing Xu, Zhengyang Bai, Qiang Ma, 2023 IEEE International Conference on High Performance Computing & Communications, Data Science & Systems, Smart City & Dependability in Sensor, Cloud & Big Data Systems & Application (HPCC/DSS/SmartCity/DependSys), pp. 972--979, Melbourne, Australia, Dec 2023. link
Construction of Hierarchical Matrix on Distributed Memory Systems using a Task Parallel Language, Zhengyang Bai, Tasuku Hiraishi, Akihiro Ida, Masaguri Yasugi, Keiichiro Fukazawa, 2022 The Tenth International Symposium on Computing and Networking Workshops (CANDARW), pp. 48--54, Himeji, Japan, Nov 2022. link
Parallelization of Matrix Partitioning in Hierarchical Matrix Construction on Distributed Memory Systems, Zhengyang Bai, Tasuku Hiraishi, Akihiro Ida, Masahiro Yasugi, Journal of Information Processing, Vol. 30, pp. 742--754, Oct 2022. link
Parallelization of Matrix Partitioning in Construction of Hierarchical Matrices using Task Parallel Languages, Zhengyang Bai, Tasuku Hiraishi, Hiroshi Nakashima, Akihiro Ida, Masahiro Yasugi, Journal of Information Processing, Vol. 27, pp. 840--851, Nov 2019. link

Non-Peer-Reviewed Papers

Graphical Ray Casting Representation of Directed Acyclic Graph in Critical Path Detection, Zhengyang Bai, Peng Chen, Lingqi Zhang, Chen Zhuang, Tenindra Abeywickrama, Jing Xu, Du Wu, Emil Vatai, Mohamed Wahib, Research Report in High-Performance Computing (HPC), Vol. 2025-HPC-200(15), pp. 1--7, Takamatsu, Japan, Aug 2025. link
Towards Hybrid CPU-GPU Computing in a Backtracking-based Load Balancing Framework, Jing Xu, Tasuku Hiraishi, Zhengyang Bai, Keiichiro Fukazawa, Masahiro Yasugi, Bulletin of Networking, Computing, Systems, and Software, Vol. 14, No. 1, pp. 58--67, Jan 2025. link
Research on Parallel Hierarchical Matrix Construction, Zhengyang Bai, Dissertation, Kyoto University, Mar 2023. link
Recommending POIs for Tourists by User Behavior Modeling and Pseudo-Rating, Kun Yi, Ryu Yamagishi, Taishan Li, Zhengyang Bai, Qiang Ma, arXiv preprint arXiv:2110.06523, Nov 2021. link

Presentations

Graphical Representation for Directed Acyclic Graph with Ray Tracing Cores Acceleration, Zhengyang Bai, Peng Chen, Chen Zhuang, Jing Xu, Emil Vatai, Mohamed Wahib, The international Conference on High Performance Computing in Aisa-Pacific Region (HPC ASIA 2025), Poster, Hsinchu, Taiwan, Feb 2025. link
Critical Path Detecting with Ray Tracing Cores Acceleration, Zhengyang Bai, Peng Chen, Chen Zhuang, Jing Xu, Emil Vatai, Mohamed Wahib, The 7th R-CCS International Symposium, Poster, Kobe, Japan, Jan 2025. link
Leveraging Ray-casting for Task Splitting over Processing Elements, Zhengyang Bai, Mohamed Wahib, Emil Vatai, Chen Zhuang, Peng Chen, Cross-disciplinary Workshop on Computing Systems, Infrastructures, and Programming (xSIG2024), Poster, Tokushima, Japan, Aug 2024. link
Critical Path Detecting by Ray-casting with Ray-tracing Cores Acceleration, Zhengyang Bai, Mohamed Wahib, Chen Zhuang, Peng Chen, Joint Laboratory for Extreme-Scale Computing (JLESC16), Poster, Kobe, Japan, Apr 2024. link
Efficient Edge-Cloud Computing and Communication Platform, Peng Chen, Yiyu Tan, Du Wu, Zhengyang Bai, Mohamed Wahib, Yusuke Tanimura, The 6th R-CCS International Symposium, Poster, Kobe, Japan, Jan 2024. link
Leveraging Ray Casting for Task Splitting over Processing Elements, Zhengyang Bai, The 247th R-CCS Cafe, Kobe, Japan, Jul 2023. link
Parallelization of Matrix Partitioning in Hierarchical Matrix Construction Using Node-aware Work Stealing, Zhengyang Bai, Tasuku Hiraishi, Akihiro Ida, Masahiro Yasugi, the 138th Research Meeting of SIGPRO (PRO-2021-5), Information Processing Society of Japan, Tsukuba, Japan, Mar 2022. link
Task Parallel Language Tascell and its Application to Hierarchical Matrices(in Japanese), Zhengyang Bai, The 14th ICT Innovation, Poster, Kyoto, Japan, Feb 2020. link
Implementation of Partitioning of Hierarchical Matrices using Task Parallel Languages, Zhengyang Bai, Tasuku Hiraishi, Hiroshi Nakashima, Akihiro Ida, Masahiro Yasugi, The 48th International Conference on Parallel Processing (ICPP2019), Poster, Kyoto, Japan, Aug 2019. Best Poster Award link
Parallelization of Matrix Partitioning in Construction of Hierarchical Matrices using Task Parallel Languages, Zhengyang Bai, Tasuku Hiraishi, Hiroshi Nakashima, Akihiro Ida, Masahiro Yasugi, Cross-disciplinary Workshop on Computing Systems, Infrastructures, and Programming (xSIG2019), May 2019. Outstanding Research Award link
Hierarchical Matrices and its Parallelization by Dynamic Load Balancing(in Japanese), Zhengyang Bai, The 13th ICT Innovation, Kyoto, Japan, Feb 2019. link
Parallelization of Matrix Partitioning in Construction of Hierarchical Matrices using Task Parallel Languages, Zhengyang Bai, Tasuku Hiraishi, Hiroshi Nakashima, Akihiro Ida, Masahiro Yasugi, the 122th Research Meeting of SIGPRO (PRO-2018-4), Information Processing Society of Japan, Fukuyama, Japan, Feb 2019. link
Parallelization of Matrix Partitioning in Construction of Hierarchical Matrices by Cilk Plus(in Japanese), Zhengyang Bai, Tasuku Hiraishi, Akihiro Ida, Hiroshi Nakashima, Masahiro Yasugi, The 20th Programming and Programming Language Workshop (PPL2018), Poster, Yonago, Japan, Mar 2018. link

Research Funds

National Grants

Grants-in-Aid for Scientific Research (KAKENHI): Grant-in-Aid for Early-Career Scientists (WAKATE)
Japan Society for the Promotion of Science, Principal Investigator, Apr 2024 -- Mar 2026.
Project Name: Leveraging Ray Casting for Task Splitting over Processing Elements
Grant Number: 24K20782
SPRING: Support for Pioneering Research Initiated by the Next Generation
Japan Science and Technology Agency, Principal Investigator, Dec 2021 -- Mar 2022.
Project Name: Data Locality-Aware Dynamic Load Balancing and Its Application to Large-Scale Parallelization of Hierarchical Matrix Computations. (in Japanese)
Grant Number: JPMJSP2110

Institute Funding

RIKEN Insentive Research Projects
RIKEN, Principal Investigator, Apr 2026 -- Mar 2027.
Project Name: Graphical Ray Casting Representation for Bayesian Networks Inference
RIKEN Collaboration Seed Fund
RIKEN, Collaborator, Apr 2026 -- Mar 2027.
Project Name: High-Performance Tensor Learning: Efficient Decomposition via Hardware-Algorithm Co-Design
Daxia Undergraduate Research Fund
East China Normal University, Member, Dec 2013 -- Nov 2014.
Project Name: Android Software for Chinese Foreign Exchange Market and Feasibility Analysis of Its Arbitrage Opportunities. (in Chinese)

Academic Activities

Conference Committee Experience

Program Committee Member, International Workshop on GPU Computing and AI (GCA), 2025 -- 2026.
Technical Program Committee Member, IEEE International Symposium on Parallel and Distributed Computing (ISPDC), 2026.
Session Chair, The SupercomputingAsia (SCA) / The International Conference on High Performance Computing in Asia-Pacific Region (HPCAsia), 2026.
Poster Chair, R-CCS International Symposium, 2024.
Sub-reviewer, International Conference on Database and Expert Systems Applications (DEXA), 2023.

Peer Review Service

Transactions on Mathematical Software, 2026.
Journal of Electronic Imaging, 2026.
Expert Systems With Applications, 2026.
The Journal of Supercomputing, 2025.
IEICE Transactions on Information and Systems, 2025.
Journal of Geovisualization and Spatial Analysis, 2025.

Other Activities

Team Leader, ACM SIGSPATIAL Cup 2025, May -- Sep 2025.
Coach, 2024 APAC HPC-AI Competition, Jun -- Nov 2024.
Staff, RIKEN Open Day, Nov 2023.
Student Staff, The 48th International Conference on Parallel Processing (ICPP2019), Aug 2019.
Student, International HPC Summer School (IHPCSS) 2019, Jul 2019.
Student, The 3rd RIKEN R-CCS HPC Youth Workshop, Feb 2019.
Student Staff, The 20th Programming and Programming Language Workshop (PPL2018), Mar 2018.

Details

Address: Nihobashi 1-chome Mitsui Building, 15th floor, 1-4-1 Nihonbashi, Chuo-ku, Tokyo 103-0027, Japan.

Email: zhengyang.bai@riken.jp

Tel: +81-50-3495-0238

Skills

C C++ OpenMP MPI OptiX CUDA Tascell Cilk Plus Fortran OpenACC linux git Python Jupyter R VBA SQL Java Javascript Matlab Visual Basic