Ryuhei UEHARA


The Convex Configurations of “Sei Shonagon Chie no Ita,” Tangram, and Other Silhouette Puzzles with Seven Pieces
Eli FOX-EPSTEIN Kazuho KATSUMATA Ryuhei UEHARA 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2016/06/01
Vol. E99-A  No. 6  pp. 1084-1089
Type of Manuscript:  Special Section PAPER (Special Section on Discrete Mathematics and Its Applications)
Category: 
Keyword: 
dissection puzzleenumerationSei Shonagon Chie no Itasilhouette puzzletangram
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Secure Sets and Defensive Alliances in Graphs: A Faster Algorithm and Improved Bounds
Kazuyuki AMANO Kyaw May OO Yota OTACHI Ryuhei UEHARA 
Publication:   IEICE TRANSACTIONS on Information and Systems
Publication Date: 2015/03/01
Vol. E98-D  No. 3  pp. 486-489
Type of Manuscript:  Special Section PAPER (Special Section on Foundations of Computer Science---New Spirits in Theory of Computation and Algorithm---)
Category: 
Keyword: 
secure setdefensive alliancefixed-parameter tractabilityhypercube
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Computational Complexity and an Integer Programming Model of Shakashaka
Erik D. DEMAINE Yoshio OKAMOTO Ryuhei UEHARA Yushi UNO 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2014/06/01
Vol. E97-A  No. 6  pp. 1213-1219
Type of Manuscript:  Special Section PAPER (Special Section on Discrete Mathematics and Its Applications)
Category: 
Keyword: 
integer programmingNP-completenesspencil-and-paper puzzleShakashaka
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Computational Complexity of Piano-Hinged Dissections
Zachary ABEL Erik D. DEMAINE Martin L. DEMAINE Takashi HORIYAMA Ryuhei UEHARA 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2014/06/01
Vol. E97-A  No. 6  pp. 1206-1212
Type of Manuscript:  Special Section PAPER (Special Section on Discrete Mathematics and Its Applications)
Category: 
Keyword: 
GeoLoophinged dissectionIvan's HingeNP-hardnesspaper folding
 Summary | Full Text:PDF(2.3MB)

Reconstruction Algorithms for Permutation Graphs and Distance-Hereditary Graphs
Masashi KIYOMI Toshiki SAITOH Ryuhei UEHARA 
Publication:   IEICE TRANSACTIONS on Information and Systems
Publication Date: 2013/03/01
Vol. E96-D  No. 3  pp. 426-432
Type of Manuscript:  Special Section PAPER (Special Section on Foundations of Computer Science — New Trends in Algorithms and Theory of Computation —)
Category: 
Keyword: 
the graph reconstruction conjecturepermutation graphspolynomial time algorithm
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Voronoi Game on a Path
Masashi KIYOMI Toshiki SAITOH Ryuhei UEHARA 
Publication:   IEICE TRANSACTIONS on Information and Systems
Publication Date: 2011/06/01
Vol. E94-D  No. 6  pp. 1185-1189
Type of Manuscript:  PAPER
Category: Fundamentals of Information Systems
Keyword: 
Discrete Voronoi gamecombinatorial game theory
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Random Generation and Enumeration of Proper Interval Graphs
Toshiki SAITOH Katsuhisa YAMANAKA Masashi KIYOMI Ryuhei UEHARA 
Publication:   IEICE TRANSACTIONS on Information and Systems
Publication Date: 2010/07/01
Vol. E93-D  No. 7  pp. 1816-1823
Type of Manuscript:  PAPER
Category: Fundamentals of Information Systems
Keyword: 
countingenumerationproper interval graphsrandom generationunit interval graphs
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FOREWORD
Ryuhei UEHARA 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2008/09/01
Vol. E91-A  No. 9  pp. 2283-2283
Type of Manuscript:  FOREWORD
Category: 
Keyword: 
 Summary | Full Text:PDF(52.6KB)

Longest Path Problems on Ptolemaic Graphs
Yoshihiro TAKAHARA Sachio TERAMOTO Ryuhei UEHARA 
Publication:   IEICE TRANSACTIONS on Information and Systems
Publication Date: 2008/02/01
Vol. E91-D  No. 2  pp. 170-177
Type of Manuscript:  Special Section PAPER (Special Section on Foundations of Computer Science)
Category: Graph Algorithms
Keyword: 
dynamic programmingHamiltonian path/cycle problemlongest path/cycle problemPtolemaic graphs
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Parallel Algorithms for Maximal Linear Forests
Ryuhei UEHARA Zhi-Zhong CHEN 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 1997/04/25
Vol. E80-A  No. 4  pp. 627-634
Type of Manuscript:  Special Section PAPER (Special Section on Discrete Mathematics and Its Applications)
Category: 
Keyword: 
parallel algorithmsrandomized parallel algorithmsgraph algorithmslinear forestsmaximal matchingsmaximal independent sets
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Generalized Hi-Q is NP-Complete
Ryuhei UEHARA Shigeki IWATA 
Publication:   IEICE TRANSACTIONS (1976-1990)
Publication Date: 1990/02/25
Vol. E73-E  No. 2  pp. 270-273
Type of Manuscript:  PAPER
Category: Algorithm and Computational Complexity
Keyword: 
 Summary | Full Text:PDF(278.5KB)