研究者詳細 - 曽我部　知広

論文 - 曽我部　知広

分割表示 95 件中 41 - 60 件目／全件表示 >>

On decomposition of k-tridiagonal l-Toeplitz matrices and its applications 査読有り

Ohashi A., Sogabe T., Usuda T. S.

SPECIAL MATRICES 3 巻 ( 1 ) 頁： 200 - 206 2015年1月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Special Matrices

© 2015 A. Ohashis et al., licensee De Gruyter Open. We consider a k-tridiagonal ℓ-Toeplitz matrix as one of generalizations of a tridiagonal Toeplitz matrix. In the present paper, we provide a decomposition of the matrix under a certain condition. By the decomposition, the matrix is easily analyzed since one only needs to analyze the small matrix obtained from the decomposition. Using the decomposition, eigenpairs and arbitrary integer powers of the matrix are easily shown as applications.

DOI： 10.1515/spma-2015-0019

Web of Science

Scopus

On tensor product decomposition of k-tridiagonal Toeplitz matrices 査読有り

Asuka Ohashi, Tsuyoshi Sasaki Usuda, Tomohiro Sogabe, Fatih Yilmaz

International Journal of Pure and Applied Mathematics 103 巻 ( 3 ) 頁： 537 - 545 2015年

AN EXTENSION OF TWO CONJUGATE DIRECTION METHODS TO MARKOV CHAIN PROBLEMS 査読有り

Chun Wen, Ting-Zhu Huang, Tomohiro Sogabe

COMPUTING AND INFORMATICS 34 巻 ( 2 ) 頁： 495 - 516 2015年

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：SLOVAK ACAD SCIENCES INST INFORMATICS

Motivated by the recent applications of the conjugate residual method to nonsymmetric lineal systems by Sogabe, Sugihara and Zhang [An extension of the conjugate residual method to nonsymmetric linear systems. J. Comput. Appl. Math., Vol. 266, 2009, pp. 103-113], this paper describes two conjugate direction methods, BiCR and BiCG, and attempts to extend their applications to compute the stationary probability distribution for an irreducible Markov chain with the aim of finding an alternative basic solver. Numerical experiments show the feasibility of the BiCR and BiCG to some extent, with applications to several practical Markov chain problems.

Web of Science

Quasi-minimal residual variants of the COCG and COCR methods for complex symmetric linear systems in electromagnetic simulations 査読有り

IEEE Trans. Microw. Theory Techn. 62 巻頁： 2859-2867 2014年12月

A note on a fast breakdown-free algorithm for computing the determinants and the permanents of k-tridiagonal matrices 査読有り

Tomohiro Sogabe, Fatih Yilmaz

APPLIED MATHEMATICS AND COMPUTATION 249 巻頁： 98 - 102 2014年12月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：ELSEVIER SCIENCE INC

k-Tridiagonal matrices have attracted much attention in recent years, which are a generalization of tridiagonal matrices. In this note, a breakdown-free numerical algorithm of O(n) is presented for computing the determinants and the permanents of k-tridiagonal matrices. Even though the algorithm is not a symbolic algorithm, it never suffers from breakdown. Furthermore, it produces exact values when all entries of the k-tridiagonal matrices are given in integer. In addition, the algorithm can be simplified for a general symmetric Toeplitz case, and it generates the kth powers of Fibonacci, Pell, and Jacobsthal numbers for a certain symmetric Toeplitz case. (C) 2014 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.amc.2014.10.040

Web of Science

Scopus

An algorithm for solving nonsymmetric penta-diagonal Toeplitz linear systems 査読有り

Du Lei, Sogabe Tomohiro, Zhang Shao-Liang

APPLIED MATHEMATICS AND COMPUTATION 244 巻頁： 10 - 15 2014年10月

BiCR-type methods for families of shifted linear systems 査読有り

Xian-Ming Gu, Ting-Zhu Huang, Jing Meng, Tomohiro Sogabe, Hou-Biao Li, Liang Li

COMPUTERS & MATHEMATICS WITH APPLICATIONS 68 巻 ( 7 ) 頁： 746 - 758 2014年10月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：PERGAMON-ELSEVIER SCIENCE LTD

The shifted linear systems with non-Hermitian matrices often arise from the numerical solutions for time-dependent PDEs, computing the large-scale eigenvalue problems, control theory and so on. In the present paper, we develop two shifted variants of BiCR-type methods for solving such linear systems. These variants of BiCR-type methods take advantage of the shifted structure, so that the number of matrix-vector multiplications and the number of inner products are the same as a single linear system. Finally, extensive numerical examples are reported to illustrate the performance and effectiveness of the proposed methods. (C) 2014 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.camwa.2014.07.029

Web of Science

Scopus

A note on symmetric k-Tridiagonal matrix family and the Fibonacci numbers 査読有り

Fatih Yilmaz, Tomohiro Sogabe

International Journal of Pure and Applied Mathematics 96 巻 ( 2 ) 頁： 289 - 298 2014年

A novel algorithm for solving quasi penta-diagonal linear systems 査読有り

Ji-Teng Jia, Tomohiro Sogabe

JOURNAL OF MATHEMATICAL CHEMISTRY 51 巻 ( 3 ) 頁： 881 - 889 2013年3月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：SPRINGER

In this paper, a novel numerical algorithm for solving quasi penta-diagonal linear systems is presented. The computational costs of the algorithm is less than those of three successful algorithms given by El-Mikkawy and Rahmo (Comput Math Appl 59:1386-1396, 2010), by Lv and Le (Appl Math Comput 204:707-712, 2008), and by Jia et al. (Int J Comput Math 89:851-860, 2012). In addition, a new recursive method for inverting the quasi penta-diagonal matrices is also discussed. The implementation of the algorithm using Computer Algebra Systems (CASs) such as MATLAB and MAPLE is straightforward. Two numerical examples are given in order to demonstrate the performance and efficiency of our algorithm.

DOI： 10.1007/s10910-012-0122-7

Web of Science

Scopus

A novel algorithm and its parallelization for solving nearly penta-diagonal linear systems 査読有り

Ji-Teng Jia, Tomohiro Sogabe

INTERNATIONAL JOURNAL OF COMPUTER MATHEMATICS 90 巻 ( 2 ) 頁： 435 - 444 2013年2月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：TAYLOR & FRANCIS LTD

In the current paper, a new serial algorithm for solving nearly penta-diagonal linear systems is presented. The computational cost of the algorithm is less than or almost equal to those of recent successful algorithms [J. Jia, Q. Kong, and T. Sogabe, A fast numerical algorithm for solving nearly penta-diagonal linear systems, Int. J. Comput. Math. 89 (2012), pp. 851860; X.G. Lv and J. Le, A note on solving nearly penta-diagonal linear systems, Appl. Math. Comput. 204 (2008), pp. 707712; S.N. Neossi Nguetchue and S. Abelman, A computational algorithm for solving nearly penta-diagonal linear systems, Appl. Math. Comput. 203 (2008), pp. 629634]. Moreover, it is suitable for developing its parallel algorithms. One of the parallel algorithms is given and is shown to be promising. The implementation of the algorithms using Computer Algebra Systems such as MATLAB and MAPLE is straightforward. Two numerical examples are given in order to illustrate the validity and efficiency of our algorithms.

DOI： 10.1080/00207160.2012.725845

Web of Science

Scopus

On particular solution of ordinary differential equations with constant coefficients 査読有り

Jiteng Jia, Tomohiro Sogabe

APPLIED MATHEMATICS AND COMPUTATION 219 巻 ( 12 ) 頁： 6761 - 6767 2013年2月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：ELSEVIER SCIENCE INC

In this paper, a new method is presented for obtaining the particular solution of ordinary differential equations with constant coefficients. An explicit formula of the particular solution is derived from the use of an upper triangular Toeplitz matrix. The validity of the approach is illustrated by some examples. (C) 2013 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.amc.2012.12.080

Web of Science

Scopus

Inversion of k-tridiagonal matrices with Toeplitz structure 査読有り

Jiteng Jia, Tomohiro Sogabe, Moawwad El-Mikkawy

COMPUTERS & MATHEMATICS WITH APPLICATIONS 65 巻 ( 1 ) 頁： 116 - 125 2013年1月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：PERGAMON-ELSEVIER SCIENCE LTD

In this paper, we consider an inverse problem with the k-tridiagonal Toeplitz matrices. A theoretical result is obtained that under certain assumptions the explicit inverse of a k-tridiagonal Toeplitz matrix can be derived immediately. Two numerical examples are given to demonstrate the validity of our results. (c) 2012 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.camwa.2012.11.001

Web of Science

Scopus

An interior eigenvalue problem from electronic structure calculations 査読有り

Lee Dongjin, Miyata Takafumi, Sogabe Tomohiro, Hoshi Takeo, Zhang Shao-Liang

JAPAN JOURNAL OF INDUSTRIAL AND APPLIED MATHEMATICS 30 巻 ( 3 ) 頁： 625 - 633 2013年

An Efficient Variant of the Restarted Shifted GMRES Method for Solving Shifted Linear Systems 査読有り

Imakura,Akira, Tomohiro,Sogabe, Shao-Liang,Zhang

Journal of Mathematical Research with Applications 33 巻 ( 2 ) 頁： 127 - 141 2013年

記述言語：英語掲載種別：研究論文（学術雑誌）

We investigate the restart of the Restarted Shifted GMRES method for solving shifted linear systems. Recently the variant of the GMRES($m$) method with the {\it unfixed update} has been proposed to improve the convergence of the GMRES($m$) method for solving linear systems, and shown to have an efficient convergence property. In this paper, by applying the unfixed update to the Restarted Shifted GMRES method, we propose a variant of the Restarted Shifted GMRES method. We show a potentiality for efficient convergence within the variant by some numerical results.

Solution of generalized shifted linear systems with complex symmetric matrices 査読有り

Sogabe Tomohiro, Hoshi Takeo, Zhang Shao-Liang, Fujiwara Takeo

JOURNAL OF COMPUTATIONAL PHYSICS 231 巻 ( 17 ) 頁： 5669 - 5684 2012年7月

An order-N electronic structure theory with generalized eigenvalue equations and its application to a ten-million-atom system 査読有り

Hoshi T., Yamamoto S., Fujiwara T., Sogabe T., Zhang S-L

JOURNAL OF PHYSICS-CONDENSED MATTER 24 巻 ( 16 ) 2012年4月

A new algorithm for solving nearly penta-diagonal Toeplitz linear systems 査読有り

Jiteng Jia, Qiongxiang Kong, Tomohiro Sogabe

COMPUTERS & MATHEMATICS WITH APPLICATIONS 63 巻 ( 7 ) 頁： 1238 - 1243 2012年4月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：PERGAMON-ELSEVIER SCIENCE LTD

A new numerical algorithm for solving nearly penta-diagonal Toeplitz linear systems is presented. The algorithm is suited for implementation using Computer Algebra Systems (CASs) such as MATLAB, MACSYMA and MAPLE. Numerical examples are given in order to illustrate the efficiency of our algorithm. (C) 2011 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.camwa.2011.12.044

Web of Science

Scopus

An Efficient Variant of the GMRES(m) Method Based on the Error Equations 査読有り

Imakura Akira, Sogabe Tomohiro, Zhang Shao-Liang

EAST ASIAN JOURNAL ON APPLIED MATHEMATICS 2 巻 ( 1 ) 頁： 19 - 32 2012年2月

デフレーション型とLook-Back型のリスタートを併用したGMRES(m)法の収束特性査読有り

今倉暁, 楊済栄, 曽我部知広, 張紹良

日本応用数理学会論文誌 22 巻 ( 3 ) 頁： 117-141 2012年

記述言語：英語掲載種別：研究論文（学術雑誌）

非対称線形方程式のためのGMRES(m)法に対する改良法として,デフレーション型とLook-Back型のリスタートに着目する.本論文では,残差多項式に基づく解析を通し,両リスタート技法が異なる数理的背景に基づきGMRES(m)法の収束性を改善することを示す.またその事実に基づき,両リスタート技法を併用するGMRES(m)法の改良法を提案し,数値実験からその収束特性を検証する.

DOI： 10.11540/jsiamt.22.3_117

非対称線形方程式のためのLook-Back GMRES(m)法査読有り

今倉暁, 曽我部知広, 張紹良

日本応用数理学会論文誌 22 巻 ( 1 ) 頁： 1-21 2012年

記述言語：英語掲載種別：研究論文（学術雑誌）

近年我々は,非対称線形方程式に対するGMRES(m)法のリスタート時の初期近似解の設定法に着目し,誤差方程式の観点からGMRES(m)法の拡張法を提案した.本論文では,拡張したGMRES(m)法の残差多項式に対する解析を通し,GMRES(m)法の残差多項式を逐次再構築する"Look-Back戦略"に基づくLook-Back GMRES(m)法を提案する.また,Look-Back GMRES(m)法の有効性を数値実験から検証する.

DOI： 10.11540/jsiamt.22.1_1

　前のページ - 次のページ　

<曽我部 知広>

論文 - 曽我部 知広

<曽我部　知広>

論文 - 曽我部　知広