MORIKUNI Keiichi
- Affiliation
- Institute of Systems and Information Engineering
- Official title
- Assistant Professor
- URL
- Research fields
Mathematical informatics Foundations of mathematics/Applied mathematics Computational science - Research keywords
Numerical Computation Numerical Analysis Numerical Linear Algebra - Research projects
Development of a Foundation for Numerical Operator Algebras and its Applications 2024-04 -- (current) Keiichi MORIKUNI Japan Society of for the Promotion of Science/Grant-in-Aid for Scientific Research (B) 18,850,000Yen Development of complex moment-based methods and mathematical risk avoidance techniques for infinite dimensional eigenvalue probl 2021-04 -- (current) Akira Imakura Japan Society of for the Promotion of Science/Grant-in-Aid for Scientific Research (B) 17,030,000Yen Robust and Efficient Numerical Methods for Matrix Problems with Singularity 2020-04 -- 2025-03 Keiichi Morikuni Japan Society of for the Promotion of Science/Grants-in-Aid for Young Scientific Research 4,290,000Yen Development of eigenvalue analysis methods using a quadrature-type eigensolver with nonlinear transformations 2018-04 -- 2021-03 Tetsuya Sakurai Japan Society of for the Promotion of Science/Grant-in-Aid for Scientific Research (B) 16,770,000Yen Convergence Analysis of Krylov Subspace Methods for Singular Systems in Finite Precision Arithmetic 2018-10 -- 2018-10 Keiichi Morikuni University of Tsukuba/Short-Term Overseas Travel Grant Program in 2018 400,000Yen 精度保証および耐障害技術に基づく周回積分型固有値解法のリスク回避 2018-07 -- 2019-03 今倉 暁 筑波大学/システム情報系若手融合研究プロジェクト 500,000Yen Contour Integral-type Eigensolvers with Perturbation-Proofness for Rectangular Matrix Pencils 2017-08 -- 2018-07 Keiichi Morikuni The Hattori Hokokai Foundation, Public Interest Incorporated Foundation/Grant-in-Aid for Engineering Research 1,000,000Yen 精度保証および耐障害技術に基づく周回積分型固有値解法のリスク回避 2017-07 -- 2018-03 Imakura, A. 筑波大学/システム情報系若手融合研究プロジェクト 500,000Yen 精度保証および耐障害技術に基づく周回積分型固有値解法のリスク回避 2016-07 -- 2017-03 Imakura, A. 筑波大学/システム情報系若手融合研究プロジェクト 300,000Yen Robust and efficient solutions of large sparse constrained eigenvalue problems 2016-04 -- 2021-03 Keiichi Morikuni Japan Society of for the Promotion of Science/Grant-in-Aid for Young Scientists (B) 4,030,000Yen more... - Career history
2015-06 -- (current) University of TsukubaDepartment of Computer Science (Division of Information Engineering), Institute of Systems and Information Engineering (Faculty of Engineering, Information and Systems)Assistant Professor 2014-04 -- 2015-05 Akademie věd České republiky (Czech Academy of Sciences) Ústav informatiky (Institute of Computer Science) Postdoktorand (Postdoctoral Fellow, Czech Academy of Sciences Program of PostDoc Support) 2013-04 -- 2014-03 National Institute of InformaticsFunding Program for World-Leading Innovative R&D on Science and Technology (FIRST) "Development of the Fastest Database Engine for the Era of Very Large Database and Experiment and Evaluation of StraProject researcher, Uno Laboratory 2008-05 -- 2013-02 National Institute of InformaticsHayami LaboratoryResearch assistant - Academic background
2008-04 -- 2013-03 The Graduate University for Advanced Studies (SOKENDAI) School of Multidisciplinary Sciences Department of Informatics (Five-year Doctoral Program) 2004-04 -- 2008-03 Kyushu University School of Design Department of Acoustic Design - Degree
2013-03 Doctor of Philosophy The Graduate University for Advanced Studies 2008-03 Bachelor of Design Kyushu University - Academic societies
2013 -- (current) ILAS (International Linear Algebra Society) 2012 -- (current) SIAM (Society for Industrial and Applied Mathematics) 2008 -- (current) The Japan Society for Industrial and Applied Mathematics (JSIAM) 2014 -- 2014 Information Processing Society of Japan 2008 -- 2013 Acoustical Society of Japan - Honors & Awards
2023-06 Best presentation award at the 2023 Joint Meeting of JSIAM Activity Groups ブロックLanczos型反復法の精度改善に向けた相互作用型残差スムージング (recipient: Kensuke Aihara, co-authors: Akira Imakura, Keiichi Morikuni) 2018-09 Best Poster Award at the 2018 JSIAM Annual Meeting スペクトラル特徴量スケーリングの多クラス分類問題への拡張 (recipient: Momo Matsuda, co-authors: Keiichi Morikuni, Akira Imakura, Tetsuya Sakurai) 2017-09 Best poster award at the 2017 JSIAM Annual Meeting 複素モーメントの誤差評価を用いた周回積分型精度保証付き部分固有値計算 (Contour integral-type verified partial eigenvalue computation via errors of complex moments) 2017-06 Best Presentation Award for Young Researchers at the 2016 JSIAM Annual Meeting 長方行列束の固有値問題に対する周回積分型解法 (Contour integral-type method for eigenproblems of rectangular matrix pencils) 2015-02 Inoue Research Award for Young Scientists Inner-iteration preconditioning for least squares problems 2013-07 SIAM Student Paper Prize Inner-Iteration Krylov Subspace Methods for Least Squares Problems, SIAM J. Matrix Anal. Appl., 34 (2013), pp. 1-22" 2013-03 The Graduate University for Advanced Studies Nagakura Research Incentive Award Inner-iteration preconditioning for large-scale ill-conditioned least squares problems 2013-03 The Graduate University for Advanced Studies Research Award Inner-iteration preconditioning for large-scale ill-conditioned least squares problems 2013-03 National Institute of Informatics (NII) Best Student Award - Articles
- Block cross-interactive residual smoothing for Lanczos-type solvers for linear systems with multiple right-hand sides
Aihara Kensuke; Imakura Akira; Morikuni Keiichi
SIAM Journal on Matrix Analysis and Applications, accepted, 2025 - Block cross-interactive residual smoothing for Lanczos-type solvers for linear systems with multiple right-hand sides
Aihara Kensuke; Imakura Akira; Morikuni Keiichi
arXiv/arXiv:2412.19488 [math.NA]/pp.1-24, 2024-12-30 - Recent advances in the numerical solution of matrix problems
Hayami Ken; Morikuni Keiichi; Reichel Lothar; Zheng Ning
JOURNAL OF COMPUTATIONAL AND APPLIED MATHEMATICS/430, 2023-10-01 - Error estimate for regularized optimal transport problems via Bregman divergence
Morikuni Keiichi; Sakakibara Koya; Takatsu Asuka
arXiv/arXiv:2309.11666 [math.OC]/pp.1-19, 2023-09-22 - Verified eigenvalue and eigenvector computations using complex moments and the Rayleigh-Ritz procedure for generalized Hermitian eigenvalue problems
Akira Imakura; Keiichi Morikuni; Akitoshi Takayasu
JOURNAL OF COMPUTATIONAL AND APPLIED MATHEMATICS/424, 2023-05 - Complex moment-based methods for differential eigenvalue problems
Imakura Akira; Morikuni Keiichi; Takayasu Akitoshi
NUMERICAL ALGORITHMS/92(1:SI)/pp.693-721, 2023-01 - Cross-interactive residual smoothing for global and block Lanczos-type solvers for linear systems with multiple right-hand sides
Aihara Kensuke; Imakura Akira; Morikuni Keiichi
SIAM Journal on Matrix Analysis and Applications/43(3)/pp.1308-1330, 2022-06 - Complex moment-based methods for differential eigenvalue problems
Imakura Akira; Morikuni Keiichi; Takayasu Akitoshi
arXiv/arXiv:2205.00971 [math.NA]/pp.1-25, 2022-05 - GMRES methods for tomographic reconstruction with an unmatched back projector
Hansen Per Christian; Hayami Ken; Morikuni Keiichi
Journal of Computational and Applied Mathematics/413, 2022-04 - A stabilized GMRES method for singular and severely ill-conditioned systems of linear equations
Liao Zeyu; Hayami Ken; Morikuni Keiichi; Yin Jun-Feng
Japan Journal of Industrial and Applied Mathematics/39(2)/pp.717-751, 2022-03 - Verified eigenvalue and eigenvector computations using complex moments and the Rayleigh-Ritz procedure for generalized Hermitian eigenvalue problems
Imakura Akira; Morikuni Keiichi; Takayasu Akitoshi
arXiv/arXiv:2110.01822 [math.NA]/pp.1-18, 2021-10 - GMRES Methods for Tomographic Reconstruction with an Unmatched Back Projector
Hansen Per Christian; Hayami Ken; Morikuni Keiichi
arXiv/arXiv:2110.01481 [math.NA]/pp.1-25, 2021-10 - Analysis of the stabilized GMRES method
Ken Hayami; Zeyu Liao; Keiichi Morikuni; Jun-Feng Yin
Proceedings of the 2021 JSIAM Annual Meeting/pp.390-391, 2021-09 - Projection method for eigenproblems of linear nonsquare matrix pencils
Morikuni Keiichi
Proceedings of the 2021 JSIAM Annual Meeting/pp.384-385, 2021-09 - Projection method for eigenvalue problems of linear nonsquare matrix pencils
Morikuni Keiichi
SIAM Journal on Matrix Analysis and Applications/42(3)/pp.1381-1400, 2021-09 - Cross-interactive residual smoothing for global and block Lanczos-type solvers for linear systems with multiple right-hand sides
Aihara K.; Imakura A.; Morikuni K.
arXiv/arXiv:2106.00284 [math.NA]/pp.1-20, 2021-06 - Kaczmarz-type inner-iteration preconditioned flexible GMRES methods for consistent linear systems
Du Yi-Shu; Hayami Ken; Zheng Ning; Morikuni Keiichi; Yin ...
SIAM Journal on Scientific Computing/43(5)/pp.S345-366, 2021-06 - Online spectral classification for long-term spike sorting
Sakamoto Kotaro; Morikuni Keiichi; Sakurai Tetsuya; Matsu...
Proceedings of the 2021 5th International Conference on Medical and Health Informatics/pp.89-97, 2021-05 - Multiclass spectral feature scaling method for dimensionality reduction
Matsuda M.; Morikuni Keiichi; Imakura A.; Ye X.; Sakurai T.
Intelligent Data Analysis/24(6)/pp.1273-1287, 2020-12 - Projection method for interior eigenproblems of linear nonsquare matrix pencils
Morikuni K.
arXiv/arXiv:2007.01183v3 [math.NA]/pp.1-20, 2020-11 - A Stabilized GMRES Method for Solving Underdetermined Least Squares Problems
Liao Z.; Hayami K.; Morikuni K.; Yin J.-F.
arXiv/arXiv:2007.10853/pp.1-20, 2020-07 - Projection method for partial eigenproblems of linear matrix pencils
Morikuni K.
arXiv/arXiv:2007.01183 [math.NA]/pp.1-18, 2020-07 - Kaczmarz-type inner-iteration preconditioned flexible GMRES methods for consistent linear systems
Du Y.-S.; Hayami K.; Zheng N.; Morikuni K.; Yin J.-F.
NII Technical Report/NII-2020-003E/pp.1-14, 2020-06 - Kaczmarz-type inner-iteration preconditioned flexible GMRES methods for consistent linear systems
Du Y.-S.; Hayami K.; Zheng N.; Morikuni K.; Ying J.-F.
arXiv/arXiv:2006.10818/pp.1-17, 2020-06 - A Stabilized GMRES Method for Solving Underdetermined Least Squares Problems
Liao Z.; Hayami K.; Morikuni K.; Yin J.-F.
NII Technical Report/NII-2020-001E/pp.1-20, 2020-03 - more...
- Block cross-interactive residual smoothing for Lanczos-type solvers for linear systems with multiple right-hand sides
- Books
- 第3章 最小二乗問題の数値解法, 3.2 反復法
保國 惠一
数値線形代数の数理とHPC/共立出版/pp.141-158, 2018-08 - Inner-iteration Preconditioning for Least Squares Problems, Ph.D. Thesis
保國 惠一
2013
- 第3章 最小二乗問題の数値解法, 3.2 反復法
- Conference, etc.
- Verified numerical computation using complex moments for eigenvalue problems of differential operators and its applications to Mathieu and Schrödinger equations
Akira Imakura; Keiichi Morikuni; Akitoshi Takayasu
JSIAM Annual Meeting 2025, Tokyo, Japan, Book of Abstracts 1A-5-3/2025-09-02--2025-09-02 - Block cross-interactive residual smoothing for block Lanczos-type iterative solvers
Aihara Kensuke; Imakura Akira; Morikuni Keiichi
The 26th Conference of the International Linear Algebra Society, Kaohsiung, Taiwan/2025-06-26--2025-06-26 - Block cross-interactive residual smoothing for Lanczos-type solvers for linear systems with multiple right-hand sides
Kensuke Aihara; Akira Imakura; Keiichi Morikuni
Householder Symposium XXII, Ithaca, United States/2025-06-10--2025-06-10 - 周回積分に基づく精度保証付きRayleigh-Ritz型固有値解法の並列実装
瀬戸 翔太; 今倉 暁; 保國 惠一; 高安 亮紀
日本応用数理学会 第21回研究部会連合発表会, 岡山/2025-03-06--2025-03-06 - Analysis for the residual gap of block Lanczos-type solvers and its improvement by cross-interactive residual smoothing
Aihara Kensuke; Imakura Akira; Morikuni Keiichi
Fundamental Forum, Chengdu, China/2025-02-24--2025-02-24 - Verified computation using complex moments for Mathieu and Schrödinger eigenvalue problems
Akira Imakura; Keiichi Morikuni; Akitoshi Takayasu
Nagoya International Workshop on Numerical Analysis 2024, Nagoya, Japan/2024-10-11--2024-10-11 - 正則化最適輸送問題におけるスケーリングの影響
榊原 航也; 高津 飛鳥; 保國 惠一
日本応用数理学会2024年度年会, 京都/2024-09-16--2024-09-16 - GMRES Methods for Tomographic Reconstruction with an Unmatched Back Projector
Hayami Ken; Hansen Per Christian; Morikuni Keiichi
Finland-Japan Workshop in Industrial and Applied Mathematics,/2024-08-26--2024-08-26 - 周回積分に基づく精度保証付き固有値解法の並列実装
瀬戸 翔太; 今倉 暁; 保國 惠一; 高安 亮紀
2024年並列／分散／協調処理に関するサマー・ワークショップ（SWoPP 2024）/2024-08-09--2024-08-09 - Cross-interactive residual smoothing for reducing the residual gap of block Lanczos-type iterative methods
Aihara Kensuke; Imakura Akira; Morikuni Keiichi
The 17th SIAM East Asian Section Conference (EASIAM2024), Macao, China/2024-06-30--2024-06-30 - AB- and BA-GMRES Methods for X-Ray CT with an Unmatched Back Projector
Hansen Per Christian; Hayami Ken; Morikuni Keiichi
Big Data Inverse Problems, Edinburgh, Scotland/2024-05-20--2024-05-20 - GMRES Methods for Tomographic Reconstruction with an Unmatched Back Projector
保國 惠一
2024 TWSIAM Annual Meting, Taichung, Taiwan/2024-05-18--2024-05-18 - 相互作用型残差スムージングにおける近似解ノルムの影響について
相原 研輔; 今倉 暁; 保國 惠一
日本応用数理学会 第20回研究部会連合発表会, 長岡/2024-03-05--2024-03-05 - 最適輸送問題のBregmanダイバージェンスによる正則化の誤差評価
榊原 航也; 高津 飛鳥; 保國 惠一
2023年度応用数学合同研究集会, 京都/2023-12-14--2023-12-14 - 有限集合間の最適輸送のBregmanダイバージェンスによる正則化
榊原 航也; 高津 飛鳥; 保國 惠一
日本数学会 2023年度秋季総合分科会, 仙台/2023-09-22--2023-09-22 - Cross-interactive residual smoothing for block Lanczos-type methods for solving linear systems with multiple right-hand sides
Kensuke Aihara; Akira Imakura; Keiichi Morikuni
Minisymposium on the Stability of Numerical Linear Algebra Algorithms, 10th International Congress on Industrial and Applied Mathematics/2023-08-24--2023-08-24 - A projection method for singular eigenvalue problems of linear matrix pencils
Morikuni Keiichi; Imakura Akira
Minisymposium on the Stability of Numerical Linear Algebra Algorithms, 10th International Congress on Industrial and Applied Mathematics (ICIAM23), Tokyo, Japan/2023-08-23--2023-08-23 - GMRES methods for tomographic reconstruction with an unmatched back projector
Ken Hayami; Per Christian Hansen; Keiichi Morikuni
Minisymposium on the Recent Developments on the Numerical Solution of Least Squares Problems, 10th International Congress on Industrial and Applied Mathematics, Tokyo, Japan/2023-08-21--2023-08-21 - 微分作用素の固有値に対する複素モーメントを用いた精度保証付き数値計算
今倉 暁; 保國 惠一; 高安 亮紀
2023年並列／分散／協調処理に関するサマー・ワークショップ（SWoPP 2023）, 第35回「行列・固有値問題の解法とその応用」研究部会 単独研究会, 函館/2023-08-03--2023-08-03 - 自己共役な微分作用素の固有値に対する周回積分型精度保証付き数値解法
今倉 暁; 保國 惠一; 高安 亮紀
第49回数値解析シンポジウム, 岩手/2023-07-13--2023-07-13 - CGS系統のブロッククリロフ部分空間法の枠組み
今倉 暁; 相原 研輔; 保國 惠一
第49回数値解析シンポジウム, 岩手/2023-07-12--2023-07-12 - GMRES Methods for Tomographic Reconstruction with an Unmatched Back Projector
Hayami Ken; Hansen Per Christian; Morikuni Keiichi
The Ninth China-Russia Conference on Numerical Algebra with Applications (CRCNAA 2023), Nanton, China/2023-07-11--2023-07-11 - 無限次元固有値問題に対する複素モーメント型解法とその性能評価
今倉暁; 保國惠一; 高安 亮紀
日本応用数理学会「行列・固有値問題の解法とその応用」研究部会 第34回研究会/2022-12-06--2022-12-06 - 一般化エルミート固有値問題に対するRayleigh-Ritz版の周回積分型精度保証付き部分固有対計算
今倉暁; 保國惠一; 高安 亮紀
日本応用数理学会2022年度年会/2022-09-10--2022-09-10 - ブロックLanczos型反復法の精度改善に向けた相互作用型残差スムージング
相原 研輔; 今倉 暁; 保國 惠一
日本応用数理学会 第19回研究部会連合発表会, 岡山（ハイブリッド）/2023-03-08--2023-03-10 - more...
- Verified numerical computation using complex moments for eigenvalue problems of differential operators and its applications to Mathieu and Schrödinger equations
- Works
- MATLAB codes for a projection method for eigenvalue problems of linear nonsquare matrix pencils
Morikuni Keiichi - NIILP: Linear Program Solver
Cui Y.; Morikuni K.; Tsuchiya T.; Hayami K. - Implementation of AB-GMRES preconditioned by NE-SOR inner iterations
Morikuni K.; Hayami K. - Implementation of BA-GMRES preconditioned by NR-SOR inner iterations
Morikuni K.; Hayami K. - Splspc: Sparse Least Squares Preconditioned methods
Hayami K.; Morikuni K.; Cui X.; Yin J.-Y.; Ito T.; Goepfe...
- MATLAB codes for a projection method for eigenvalue problems of linear nonsquare matrix pencils
- Teaching
2025-05 -- 2025-08 Linear Algebra A University of Tsukuba. 2025-10 -- 2025-12 Computational Algorithm and Simulation University of Tsukuba. 2025-04 -- 2025-08 Cross-Disciplinary Seminar in Computer Science University of Tsukuba. 2025-04 -- 2025-08 Research in Computer Science Is University of Tsukuba. 2025-04 -- 2025-08 Research in Computer Science IIs University of Tsukuba. 2025-10 -- 2026-02 Research in Computer Science IIf University of Tsukuba. 2025-10 -- 2026-02 Research in Computer Science II University of Tsukuba. 2025-04 -- 2025-08 Research in Computer Science II University of Tsukuba. 2025-10 -- 2026-02 Research in Computer Science If University of Tsukuba. 2025-10 -- 2026-02 Research in Computer Science I University of Tsukuba. more... - Other educational activities
2019-04 -- (current) クラス担任 筑波大学 2021-04 -- 2023-03 情報科学特別演習, 情報特別演習I, 情報特別演習II世話人（ソフトウェアサイエンス主専攻） 筑波大学 2018-04 -- 2020-03 情報科学概論II ソフトウェアサイエンス主専攻 世話人 筑波大学 2018-04 -- 2019-03 情報科学概論I ソフトウェアサイエンス主専攻 世話人 筑波大学 2017-04 -- 2019-03 Facilitator, CS Seminar, Department of Computer Science University of Tsukuba - Professional activities
2024-01 -- (current) Japan Journal of Industrial and Applied Mathematics Editor 2018-04 -- (current) The Japan Society for Industrial and Applied Mathematics Committee Member, Activity Group on Algorithms for Matrix / Eigenvalue Problems and their Applications 2021-04 -- 2025-03 The Japan Society for Industrial and Applied Mathematics Editorial Board of Transactions of the Japan Society for Industrial and Applied Mathematics/Editor 2022-04 -- 2023-03 The Japan Society for Industrial and Applied Mathematics Representative Member 2021-04 -- 2023-03 The Japan Society for Industrial and Applied Mathematics Chair, Activity Group on Algorithms for Matrix / Eigenvalue Problems and their Applications 2021-11 -- 2021-11 Workshop on Continuous Optimization and Related Topics Organizer 2021-03 -- 2021-03 Second Workshop on Numerical Algebra, Algorithms, and Analysis Organizing Committee 2018-06 -- 2018-06 Numerical Analysis Symposium 2018 Executive Committee Member 2018-04 -- 2024-03 The Japan Society for Industrial and Applied Mathematics Secretary, Activity Group on Algorithms for Matrix / Eigenvalue Problems and their Applications 2018-04 -- 2022-03 The Japan Society for Industrial and Applied Mathematics Editor, JSIAM Letters more... - University Management
2025-04 -- (current) 教学マネジメント委員会 委員 2024-04 -- (current) Academic Computing & Communications Center 業務支援 2024-04 -- (current) 情報理工学位プログラム 学務・学生委員会 委員 2024-04 -- (current) 情報科学類 計算機運用委員会 委員 2019-04 -- (current) ヒューマニクス学位プログラム 学生支援委員会 委員 2015-06 -- (current) ヒューマンバイオロジー学位プログラム 教務委員会 委員 2023-04 -- 2025-03 情報理工学位プログラム ダイバーシティ・アクセシビリティ担当 2023-04 -- 2025-03 情報工学域 計算機運用委員会 委員 2023-04 -- 2025-03 情報科学類 広報企画委員会 委員 2022-04 -- 2024-03 スポーツ・デー運営委員会 委員 more...
(Last updated: 2025-09-03)