Updated on 2022/07/14

写真b

 
Koichi BETSUMIYA
 
Affiliation
Shizen Kagakukei(It is currently under consideration) Safety Science and Technology Section
Full-time staff
Graduate School of Science and Technology Research Division

Degree

  • 博士(数理学)

  • 修士(理学)

  • 理学学士

Research Interests

  • 数学

  • mathematics

Research Areas

  • Natural Science / Algebra

  • Natural Science / Algebra

Professional Memberships

  • The Mathematical Society of Japan

  • 日本数学会

Papers

  • tame 自己同型群について

    別宮 耕一

    第31回有限群論草津セミナー報告集   31   1 - 3   2020

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  • 拡張ハミング符号と正六百胞体との対応について

    別宮 耕一

    第30回有限群論草津セミナー報告集   30   37 - 42   2019

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  • Triply even code の極大性判定

    別宮 耕一

    第29回有限群論草津セミナー報告集   -   14 - 17   2018

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  • Triply even codes constructed from distance regular graphs (Research on finite groups and their representations, vertex operator algebras, and algebraic combinatorics)

    Betsumiya Koichi

    2003   66 - 73   2016.7

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  • 立方重偶符号の自己同型群に現れる単純群

    別宮耕一

    第27回有限群論草津セミナー報告集   29 - 32   2016.3

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  • Triply even codes constructed from distance regular graphs

    別宮 耕一

    京都大学数理解析研究所講究録   2003   66 - 73   2016

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  • 組合せ構造における純粋ナッシュ均衡性

    別宮耕一

    第26回有限群論草津セミナー報告集   6 - 8   2015.7

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  • On triply even codes

    BETSUMIYA Koichi

    RIMS Kokyuroku   1844   139 - 145   2013.7

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  • Triply even codes について (デザイン、符号、グラフおよびその周辺)

    別宮 耕一

    数理解析研究所講究録   1844   139 - 145   2013.7

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    CiNii Article

  • Upper bounds on cyclotomic numbers

    Koichi Betsumiya, Mitsugu Hirasaka, Takao Komatsu, Akihiro Munemasa

    Linear Algebra and its Applications   438 ( 1 )   111 - 120   2013.1

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  • Upper bounds on cyclotomic numbers

    Koichi Betsumiya, Mitsugu Hirasaka, Takao Komatsu, Akihiro Munemasa

    Linear Algebra and Its Applications   438 ( 1 )   111 - 120   2013.1

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  • Classification of doubly even self-dual codes of length 40

    別宮 耕一

    第29回代数的組合せ論シンポジウム報告集   10 - 16   2013

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  • A complete classification of doubly even self-dual codes of length 40

    Koichi BETSUMIYA, Masaaki HARADA, Akihiro MUNEMASA

    Electronic Journal of Combinatorics   19 ( 3 )   2012.10

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  • On triply even binary codes

    Koichi BETSUMIYA, Akihiro MUNEMASA

    Journal of the London Mathematical Society   86 ( 1 )   1 - 16   2012.8

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  • A complete classification of doubly even self-dual codes of length 40

    Koichi Betsumiya, Masaaki Harada, Akihiro Munemasa

    ELECTRONIC JOURNAL OF COMBINATORICS   19 ( 3 )   P18   2012.8

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    Web of Science

  • On triply even binary codes

    Koichi Betsumiya, Akihiro Munemasa

    JOURNAL OF THE LONDON MATHEMATICAL SOCIETY-SECOND SERIES   86 ( 1 )   1 - 16   2012.8

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  • A complete classification of doubly even self-dual codes of length 40

    別宮 耕一

    The Electronic Journal of Combinatorics   19   18   2012

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  • Hadamard matrices of order 32 and extremal ternary self-dual codes

    Koichi Betsumiya, Masaaki Harada, Hiroshi Kimura

    Designs, Codes and Cryptography. An International Journal   58 ( 2 )   203 - 214   2011.2

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  • Hadamard matrices of order 32 and extremal ternary self-dual codes

    Koichi Betsumiya, Masaaki Harada, Hiroshi Kimura

    DESIGNS CODES AND CRYPTOGRAPHY   58 ( 2 )   203 - 214   2011.2

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  • Invariant ring of Clifford-Weil group, and Jacobi forms over totally real field

    別宮 耕一

    Séminaires et Congrès   21   1 - 16   2011

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  • Hadamard matrices of order 32 and extremal ternary self-dual codes

    別宮 耕一, 原田 昌晃

    Designs, Codes and Cryptography 58   203 - 214   2011

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  • Hadamard matrices of order 32 and extremal ternary self-dual codes

    別宮 耕一

    Designs, Codes and Cryptography   58   203 - 214   2011

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  • Invariant ring of Clifford-Weil group, and Jacobi forms over totally real field.

    BETSUMIYA Koichi, Choie, YoungJu

    Sémin. Congr.,   21   1 - 16   2010

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  • Invariant Ring of Clifford-Weil Group, and Jacobi Forms over Totally Real Field (共著)

    Koichi BETSUMIYA, YoungJu CHOIE

    Séminaires et Congrès   21   1 - 16   2009.12

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  • Mass Formula for Even Codes over Z4 (共著)

    Koichi Betsumiya, Rowena Alma L. Betty and Akihiro Munemasa

    Springer-Verlag Lecture Notes in Computer Science   5921   15 - 17   2009.12

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  • Mass Formula for Even Codes over ZZ(8)

    Koichi Betsumiya, Rowena Alma L. Betty, Akihiro Munemasa

    CRYPTOGRAPHY AND CODING, PROCEEDINGS   5921   65 - +   2009

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    Web of Science

  • Mass formula for even codes over Z_8、Cryptography and Coding

    別宮 耕一, 宗政 昭弘

    Springer LNCS 5921   65 - 77   2009

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  • Mass Formula for Even Codes over Z_8

    別宮 耕一, 宗政 昭弘

    Cryptography and Coding, Springer LNCS 5921   65 - 77   2009

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  • Mass formula for even codes over Z_8

    別宮 耕一, 宗政 昭弘

    Cryptography and Coding, Springer LNCS 5921   65 - 77   2009

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  • Invariant Ring of Clifford-Weil Group, and Jacobi Forms over Totally Real Field

    別宮 耕一

    Seminaires et Congres 21   1 - 16   2009

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  • Minimum Lee weights of type II codes over F2r

    Koichi BETSUMIYA

    Discrete Mathematics   308 ( 14 )   3018 - 3022   2008.7

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  • Minimum Lee weights of Type II codes over F-2r

    Koichi Betsumiya

    DISCRETE MATHEMATICS   308 ( 14 )   3018 - 3022   2008.7

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  • Minimum Lee weights of Type II code over F_2^r

    別宮 耕一

    Discrete Mathematics 308   3018 - 3022   2008

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  • Type II codes over Galois rings

    別宮耕一

    第24回代数的組合せ論シンポジウム報告集   51 - 54   2007.11

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  • アダマール行列による超立方体の分割

    別宮耕一

    第18回有限群論草津セミナー報告集   69 - 70   2006.12

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  • A special self-dual code over F4

    別宮耕一

    数理解析研究所講究録   1465   119 - 125   2006.1

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  • Ozeki polynomials and Jacobi forms (共著)

    Koichi BETSUMIYA, YoungJu CHOIE

    Ars Combinatoria   77   233 - 244   2005.10

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  • Ozeki polynomials and Jacobi forms

    K Betsumiya, Y Choie

    ARS COMBINATORIA   77   233 - 244   2005.10

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  • Codes over F4, Jacobi forms and Hilbert-Siegel modular forms over Q(√5) (共著)

    Koichi BETSUMIYA, YoungJu CHOIE

    European Journal of Combinatorics   26 ( 5 )   629 - 650   2005.7

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  • Codes over F-4, Jacobi forms and Hilbert-Siegel modular forms over Q(A root 5)

    K Betsumiya, Y Choie

    EUROPEAN JOURNAL OF COMBINATORICS   26 ( 5 )   629 - 650   2005.7

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  • Jacobi forms over totally real fields and type II codes over Galois rings GR(2m,f) (共著)

    Koichi BETSUMIYA, YoungJu CHOIE

    European Journal of Combinatorics   25 ( 4 )   475 - 486   2004.5

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  • Jacobi forms over totally real fields and type II codes over Galois rings GR(2(m), f)

    K Betsumiya, Y Choie

    EUROPEAN JOURNAL OF COMBINATORICS   25 ( 4 )   475 - 486   2004.5

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  • Optimal self-dual codes over F2×F2 with respect to the Hamming weight (共著)

    Koichi BETSUMIYA, Masaaki HARADA

    IEEE Transactions on Information Theory   50 ( 2 )   356 - 358   2004.2

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  • Optimal Self-Dual Codes Over double struct F sign2 × double struct F sign2 With Respect to the Hamming Weight

    Koichi Betsumiya, Masaaki Harada

    IEEE Transactions on Information Theory   50 ( 2 )   356 - 410   2004.2

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  • Optimal self-dual codes over F-2 x F-2 with respect to the hamming weight

    K Betsumiya, M Harada

    IEEE TRANSACTIONS ON INFORMATION THEORY   50 ( 2 )   356 - 358   2004.2

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  • Type II codes over F2m+uF2m (共著)

    Koichi BETSUMIYA, San LING, Fidel R. NEMENZO

    Discrete Mathematics   275 ( 1-3 )   43 - 65   2004.1

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  • Type II codes over F-2(m)+ uF(2)(m)

    K Betsumiya, S Ling, FR Nemenzo

    DISCRETE MATHEMATICS   275 ( 1-3 )   43 - 65   2004.1

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  • Formally self-dual codes related to Type II codes (共著)

    Koichi BETSUMIYA, Masaaki HARADA

    Applicable Algebra in Engineering, Communication and Computing   14 ( 2 )   81 - 88   2003.8

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  • Formally self-dual codes related to Type II codes

    K Betsumiya, M Harada

    APPLICABLE ALGEBRA IN ENGINEERING COMMUNICATION AND COMPUTING   14 ( 2 )   81 - 88   2003.8

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  • Extremal self-dual codes over F2×F2 (共著)

    Koichi BETSUMIYA, T. Aaron GULLIVER, Masaaki HARADA

    Designs, Codes and Cryptography   28 ( 2 )   171 - 186   2003.3

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  • Extremal self-dual codes over F-2 x F-2

    K Betsumiya, TA Gulliver, M Harada

    DESIGNS CODES AND CRYPTOGRAPHY   28 ( 2 )   171 - 186   2003.3

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  • On self-dual codes over some prime fields (共著)

    Koichi Betsumiya, Stelios Georgiou, T. Aaron Gulliver, Masaaki, Harada, Christos Koukouvinos

    Discrete Mathematics   262 ( 1-3 )   37 - 58   2003.2

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  • On self-dual codes over some prime fields

    K Betsumiya, S Georgiou, TA Gullivere, M Harada, C Koukouvinos

    DISCRETE MATHEMATICS   262 ( 1-3 )   37 - 58   2003.2

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  • Type II codes over F2r (共著)

    Koichi BETSUMIYA, Masaaki HARADA, Akihiro MUNEMASA

    Springer-Verlag Lecture Notes in Computer Science   227   102 - 111   2001.11

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  • On Type II codes over F4 (共著)

    Koichi BETSUMIYA, T. Aaron GULLIVER, Masaaki HARADA, Akihiro MUNEMASA

    IEEE Transactions on Information Theory   47 ( 6 )   2242 - 2248   2001.9

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  • On type II codes over F-4

    K Betsumiya, TA Gulliver, M Harada, A Munemasa

    IEEE TRANSACTIONS ON INFORMATION THEORY   47 ( 6 )   2242 - 2248   2001.9

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  • Classification of formally self-dual even codes of lengths up to 16 (共著)

    Koichi BETSUMIYA, Masaaki HARADA

    Designs, Codes and Cryptography   23 ( 3 )   235 - 332   2001.8

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  • Binary optimal odd formally self-dual codes

    K Betsumiya, M Harada

    DESIGNS CODES AND CRYPTOGRAPHY   23 ( 1 )   11 - 21   2001.5

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  • Binary optimal odd formally self-dual codes (共著)

    Koichi BETSUMIYA, Masaaki HARADA

    Designs, Codes and Cryptography   23 ( 1 )   11 - 21   2001.3

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  • Classification of formally self-dual even codes of lengths up to 16

    K Betsumiya, M Harada

    DESIGNS CODES AND CRYPTOGRAPHY   23 ( 3 )   325 - 332   2001

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  • Type II Codes over F2r.

    Koichi Betsumiya, Masaaki Harada, Akihiro Munemasa

    Applied Algebra, Algebraic Algorithms and Error-Correcting Codes, 14th International Symposium, AAECC-14, Melbourne, Australia November 26-30, 2001, Proceedings   102 - 111   2001

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  • On type II codes over F-4

    K Betsumiya, TA Gulliver, M Harada, A Munemasa

    2000 IEEE INTERNATIONAL SYMPOSIUM ON INFORMATION THEORY, PROCEEDINGS   47 ( 6 )   141 - 141   2000

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  • Binary optimal linear rate 1/2 codes (共著)

    Koichi BETSUMIYA, Masaaki HARADA

    Springer-Verlag Lecture Notes in Computer Science   1719   462 - 471   1999.11

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  • On binary extremal formally self-dual even codes (共著)

    Koichi BETSUMIYA, T. Aaron GULLIVER, Masaaki HARADA

    Kyushu Journal of Mathematics   53 ( 2 )   421 - 430   1999.9

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  • On binary extremal formally self-dual even codes

    Koichi Betsumiya, T. Aaron Gulliver, Masaaki Harada

    Kyushu Journal of Mathematics   53 ( 2 )   421 - 430   1999

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  • Binary optimal linear rate 1/2 codes

    K Betsumiya, TA Gulliver, M Harada

    APPLIED ALGEBRA, ALGEBRAIC ALGORITHMS AND ERROR-CORRECTING CODES, PROCEEDINGS   1719   462 - 471   1999

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Books

  • The Mathematics behind Cryptography

    ( Role: Joint author)

    Hirosaki University Press  2020.9 

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    Language:Japanese Book type:Textbook, survey, introduction

Review Papers

  • Triply even codes constructed from distance regular graphs (Research on finite groups and their representations, vertex operator algebras, and algebraic combinatorics)

    Betsumiya Koichi

    RIMS Kokyuroku   ( 2003 )   66 - 73   2016.7

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    Language:Japanese   Publishing type:Rapid communication, short report, research note, etc. (scientific journal)   Publisher:Kyoto University   Kind of work:Single Work  

    CiNii Article

  • Triply even codesについて (デザイン、符号、グラフおよびその周辺 : RIMS共同研究報告集)

    別宮 耕一

    数理解析研究所講究録   ( 1844 )   139 - 145   2013.7

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    Language:Japanese   Publishing type:Rapid communication, short report, research note, etc. (scientific journal)   Publisher:京都大学   Kind of work:Single Work  

    CiNii Article

  • Classification of Type II code over GF(4) of some small lengths (Codes, lattices, vertex operator algebras and finite groups)

    Betsumiya Koichi

    RIMS Kokyuroku   ( 1228 )   43 - 50   2001.9

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    Language:English   Publishing type:Rapid communication, short report, research note, etc. (scientific journal)   Publisher:Kyoto University   Kind of work:Single Work  

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Social Activities

  • オープンキャンパス

    2009.09

  • 理工学部サイエンステクノフェア

    2009.08

  • 第6回弘前大学FDワークショップ

    2009.06