Akira Hiraki

(平木彰)

Profile Information

Affiliation: Professor, Division of Math, Sciences, and Information Technology in Education, Osaka Kyoiku University

Degree: (BLANK)(Osaka Kyoiku University)
修士(教育学)(大阪教育大学)
(BLANK)(Osaka University)
博士(理学)(大阪大学)

Researcher number: 90294181
J-GLOBAL ID: 200901064255237256
researchmap Member ID: 6000008567

Research Interests

Research Areas

Research History

Apr, 2014

教授, 教育学部, 大阪教育大学
Apr, 2007

准教授, 教育学部, 大阪教育大学

Education

Apr, 1992 - Jul, 1995

数学, Graduate School, Division of Natural Science, Osaka University
Apr, 1990 - Mar, 1992

数学教育, Graduate School, Division of Education, Osaka Kyoiku University
Apr, 1985 - Mar, 1989

特別数学課程, Faculty of Education, Osaka Kyoiku University

Misc.

A Characterization of the Hamming Graphs and the Dual Polar Graphs by Completely Regular Subgraphs

Akira Hiraki

Graphs and Combinatorics, 28(4) 449-467, Jul, 2012
Delsarte Set Graphs with Small c(2)

S. Bang, A. Hiraki, J. H. Koolen

GRAPHS AND COMBINATORICS, 26(2) 147-162, Mar, 2010
A characterization of some distance-regular graphs by strongly closed subgraphs

Akira Hiraki

EUROPEAN JOURNAL OF COMBINATORICS, 30(4) 893-907, May, 2009
Distance-Regular Graph with c(2) > 1 and a(1)=0 < a(2)

Akira Hiraki

GRAPHS AND COMBINATORICS, 25(1) 65-79, May, 2009
Strongly Closed Subgraphs in a Distance-Regular Graph with c (2) > 1

Akira Hiraki

GRAPHS AND COMBINATORICS, 24(6) 537-550, Nov, 2008
A characterization of the Hamming graph by strongly closed subgraphs

Akira Hiraki

European Journal of Combinatorics, 29(7) 1603-1616, Oct, 2008
Delsarte clique graphs

S. Bang, A. Hiraki, J. H. Koolen

EUROPEAN JOURNAL OF COMBINATORICS, 28(2) 501-516, Feb, 2007
A characterization of the Odd graphs and the doubled Odd graphs with a few of their intersection numbers

Akira Hiraki

EUROPEAN JOURNAL OF COMBINATORICS, 28(1) 246-257, Jan, 2007
Improving diameter bounds for distance-regular graphs

European Journal of Combinatoric, 27(1) 78-89, 2006
Applications of the retracing method for distance-regular graphs

A Hiraki

EUROPEAN JOURNAL OF COMBINATORICS, 26(5) 717-727, Jul, 2005
A generalization of an inequality of Brouwer-Wilbrink

A Hiraki, J Koolen

JOURNAL OF COMBINATORIAL THEORY SERIES A, 109(1) 181-188, Jan, 2005
A note on regular near polygons

A Hiraki, J Koolen

GRAPHS AND COMBINATORICS, 20(4) 485-497, Nov, 2004
The regular near polygons of order (s,2)

Journal of Algebraic Combinatorics, 20(3) 219-235, 2004
A Higman-Haemers inequality for thick regular near polygons

20(3) 213-218, 2004
A distance-regular graph with bipartite geodetically closed subgraphs

A Hiraki

EUROPEAN JOURNAL OF COMBINATORICS, 24(4) 349-363, May, 2003
A characterization of the doubled Grassmann graphs, the doubled Odd graphs, and the Odd graphs by strongly closed subgraphs

A Hiraki

EUROPEAN JOURNAL OF COMBINATORICS, 24(2) 161-171, Feb, 2003
The number of columns (1,k-2,1) in the intersection array of a distance-regular graph

A Hiraki

GRAPHS AND COMBINATORICS, 19(3) 371-387, 2003
An improvement of the Godil bound

Annals of Combinatorics, 6 33-44, 2002 Peer-reviewed
A distance-regular graph with strongly closed subgraphs

A Hiraki

JOURNAL OF ALGEBRAIC COMBINATORICS, 14(2) 127-131, Sep, 2001
Retracing argument for distance-regular graphs

A Hiraki

JOURNAL OF COMBINATORIAL THEORY SERIES B, 79(2) 211-220, Jul, 2000
Distance-regular graphs of valency 6 and a(1)=1

A Hiraki, K Nomura, H Suzuki

JOURNAL OF ALGEBRAIC COMBINATORICS, 11(2) 101-134, Mar, 2000
Geodecically closed subgraphs in a distance-regular graph

Kyushu Journal of Mathematics, 54 155--164, 2000 Peer-reviewed
An application of a construction theory of strongly closed subgraphs in a distance-regular graph

A Hiraki

EUROPEAN JOURNAL OF COMBINATORICS, 20(4) 271-278, May, 1999
On the non existance of certain distance-regular graphs

Kyushu Journal of Mathematics, 53 1--15, 1999 Peer-reviewed
Distance-regular graphs of the height h

Akira Hiraki

Graphs and Combinatorics, 15(4) 417-428, 1999
Strongly Closed Subgraphs in a Regular Thick Near Polygon

Akira Hiraki

European Journal of Combinatorics, 20(8) 789-796, 1999
Distance-regular subgraphs in a distance-regular graph, VI

A Hiraki

EUROPEAN JOURNAL OF COMBINATORICS, 19(8) 953-965, Nov, 1998
Distance-regular subgraphs in a distance-regular graph, V

A Hiraki

EUROPEAN JOURNAL OF COMBINATORICS, 19(2) 141-150, Feb, 1998
An Improvement of the Ivanov bound

Annals of Combinatiorics, 2 131-135, 1998
Distance-regular graphs with b_d-i=c_i and antipodal double covers

Journal of algebraic Combinatorics, 8 127-138, 1998 Peer-reviewed
On distance-regular graphs with c₄ = 1 and a₁ ≠ a₂

Kyushu Journal of Mathematics, 52 265--277, 1998
Distance-regular graphs with b_d-i=c_i and antipodal double covers

Journal of algebraic Combinatorics, 8 127-138, 1998
Distance-regular graphs with b(2)=1 and antipodal covers

M Araya, A Hiraki, A Jurisic

EUROPEAN JOURNAL OF COMBINATORICS, 18(3) 243-248, Apr, 1997
Distance-regular subgraphs in a distance-regular graph, III

European Journal of Combinatorics, 17 629-636, 1996
Distance-regular graphs with b_t=1 and antipodal double-covers

Journal of Combinatorics Ser. B, 67 278-248, 1996
A constant bound on the number of columns (1, k - 2, 1) in the intersection array of a distance-regular graph

Akira Hiraki

Graphs and Combinatorics, 12(1) 23-37, 1996
Distance-regular subgraphs in a distance-regular graph, III

Akira Hiraki

European Journal of Combinatorics, 17(7) 629-636, 1996
On distance-regular graphs with ki =kj, II

Akira Hiraki, Hiroshi Suzuki, Masayuki Wajima

Graphs and Combinatorics, 11(4) 305-317, Dec, 1995
Distance-regular subgrayphs in a distance-regular graph II

European Journal of Combinatorics, 16 603-615, 1995
Distance-regular subgrayphs in a distance-regular graph I

European Journal of Combinatorics, 16 589-602, 1995 Peer-reviewed
Circuit chasing technigue for a distance-regular graph with c_2r+1

Kyushu Journal of Mathmatics, 49 197-219, 1995
An improvement of the Boshior-Namura Bound

Journal of Combinatorics Ser(B), 61 1-4, 1994 Peer-reviewed
A CIRCUIT CHASING TECHNIQUE IN A DISTANCE-REGULAR GRAPH WITH TRIANGLES

A HIRAKI

EUROPEAN JOURNAL OF COMBINATORICS, 14(5) 413-420, Sep, 1993
On distance-regular graphs with b₁=c_d-1

Mathmatica Japonica, 37 751-756, 1992 Peer-reviewed

Professional Memberships

日本数学会

Research Projects

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