Shuji ISOBE


Autoreducibility and Completeness for Partial Multivalued Functions
Shuji ISOBE Eisuke KOIZUMI 
Publication:   
Publication Date: 2017/03/01
Vol. E100-D  No. 3  pp. 422-427
Type of Manuscript:  Special Section PAPER (Special Section on Foundations of Computer Science — New Trends in Theoretical Computer Science —)
Category: 
Keyword: 
partial multivalued functionautoreductionmany-one-like reduction
 Summary | Full Text:PDF(198.8KB)

A Strengthened Security Notion for Password-Protected Secret Sharing Schemes
Shingo HASEGAWA Shuji ISOBE Jun-ya IWAZAKI Eisuke KOIZUMI Hiroki SHIZUYA 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2015/01/01
Vol. E98-A  No. 1  pp. 203-212
Type of Manuscript:  Special Section PAPER (Special Section on Cryptography and Information Security)
Category: Foundation
Keyword: 
password-protected secret sharingtwin ElGamal encryptionsimulation-sound non-interactive zero-knowledge
 Summary | Full Text:PDF(837.2KB)

A Lossy Identification Scheme Using the Subgroup Decision Assumption
Shingo HASEGAWA Shuji ISOBE 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2014/06/01
Vol. E97-A  No. 6  pp. 1296-1306
Type of Manuscript:  Special Section PAPER (Special Section on Discrete Mathematics and Its Applications)
Category: 
Keyword: 
lossy identification schemesthe Fiat-Shamir heuristicthe subgroup decision assumptionthe DCR assumption
 Summary | Full Text:PDF(356.5KB)

On the Complexity of Computing Discrete Logarithms over Algebraic Tori
Shuji ISOBE Eisuke KOIZUMI Yuji NISHIGAKI Hiroki SHIZUYA 
Publication:   IEICE TRANSACTIONS on Information and Systems
Publication Date: 2014/03/01
Vol. E97-D  No. 3  pp. 442-447
Type of Manuscript:  Special Section PAPER (Special Section on Foundations of Computer Science —New Trends in Theory of Computation and Algorithm—)
Category: Fundamentals of Information Systems
Keyword: 
algebraic toriorder certified discrete logarithmTuring reduction
 Summary | Full Text:PDF(381.4KB)

The RSA Group Is Adaptive Pseudo-Free under the RSA Assumption
Masayuki FUKUMITSU Shingo HASEGAWA Shuji ISOBE Hiroki SHIZUYA 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2014/01/01
Vol. E97-A  No. 1  pp. 200-214
Type of Manuscript:  Special Section PAPER (Special Section on Cryptography and Information Security)
Category: Public Key Based Cryptography
Keyword: 
pseudo-freenessadaptive pseudo-free groupsRSA assumption
 Summary | Full Text:PDF(606.3KB)

On the Length-Decreasing Self-Reducibility and the Many-One-Like Reducibilities for Partial Multivalued Functions
Ji-Won HUH Shuji ISOBE Eisuke KOIZUMI Hiroki SHIZUYA 
Publication:   IEICE TRANSACTIONS on Information and Systems
Publication Date: 2013/03/01
Vol. E96-D  No. 3  pp. 465-471
Type of Manuscript:  Special Section PAPER (Special Section on Foundations of Computer Science — New Trends in Algorithms and Theory of Computation —)
Category: 
Keyword: 
partial multivalued functionlength-decreasing self-reductionmany-one-like reduction
 Summary | Full Text:PDF(265.1KB)

NPMV-Complete Functions That Compute Discrete Logarithms and Integer Factorization
Shingo HASEGAWA Shuji ISOBE Hiroki SHIZUYA 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2008/01/01
Vol. E91-A  No. 1  pp. 342-344
Type of Manuscript:  Special Section LETTER (Special Section on Cryptography and Information Security)
Category: 
Keyword: 
NPMVNPMV-completediscrete logarithminteger factoring
 Summary | Full Text:PDF(78.6KB)

Making Cryptographic Primitives Harder
Shingo HASEGAWA Hiroyuki HATANAKA Shuji ISOBE Eisuke KOIZUMI Hiroki SHIZUYA 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2008/01/01
Vol. E91-A  No. 1  pp. 330-337
Type of Manuscript:  Special Section PAPER (Special Section on Cryptography and Information Security)
Category: Cryptanalysis
Keyword: 
liftingsmultivalued functionsdiscrete logarithmgraph isomorphism
 Summary | Full Text:PDF(308.7KB)

Toward Separating Integer Factoring from Discrete Logarithm mod p
Shuji ISOBE Wataru KUMAGAI Masahiro MAMBO Hiroki SHIZUYA 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2007/01/01
Vol. E90-A  No. 1  pp. 48-53
Type of Manuscript:  Special Section PAPER (Special Section on Cryptography and Information Security)
Category: Foundations
Keyword: 
preimage functionsrange injection reductionthe Heath-Brown conjectureinteger factoringcertified discrete logarithm
 Summary | Full Text:PDF(328.2KB)

On the Polynomial Time Computability of Abstract Ray-Tracing Problems
Shuji ISOBE Tetsuo KURIYAMA Masahiro MAMBO Hiroki SHIZUYA 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2005/05/01
Vol. E88-A  No. 5  pp. 1209-1213
Type of Manuscript:  Special Section PAPER (Special Section on Discrete Mathematics and Its Applications)
Category: 
Keyword: 
ray-tracing problemabstract ray-tracing problem (ARTP)PSPACE-hard/completescene
 Summary | Full Text:PDF(176.6KB)

Cost Total Colorings of Trees
Shuji ISOBE Xiao ZHOU Takao NISHIZEKI 
Publication:   IEICE TRANSACTIONS on Information and Systems
Publication Date: 2004/02/01
Vol. E87-D  No. 2  pp. 337-342
Type of Manuscript:  Special Section PAPER (Special Section on Foundations of Computer Science)
Category: 
Keyword: 
cost total coloringdynamic programmingmatchingtotal coloringtree
 Summary | Full Text:PDF(245.6KB)

Linear Algorithm for Finding List Edge-Colorings of Series-Parallel Graphs
Tomoya FUJINO Shuji ISOBE Xiao ZHOU Takao NISHIZEKI 
Publication:   IEICE TRANSACTIONS on Information and Systems
Publication Date: 2003/02/01
Vol. E86-D  No. 2  pp. 186-190
Type of Manuscript:  Special Section PAPER (Special Issue on Selected Papers from LA Symposium)
Category: Graph Algorithms
Keyword: 
algorithmlist edge-coloringseries-parallel graph
 Summary | Full Text:PDF(241.7KB)