Toshiya ITOH


On Aggregating Two Metrics with Relaxed Triangle Inequalities by the Weighted Harmonic Mean
Toshiya ITOH Yoshinori TAKEI 
Publication:   
Publication Date: 2018/09/01
Vol. E101-A  No. 9  pp. 1404-1411
Type of Manuscript:  Special Section PAPER (Special Section on Discrete Mathematics and Its Applications)
Category: 
Keyword: 
aggregation of metricsrelaxed triangle inequalityset similarityJaccard-Tanimoto distance
 Summary | Full Text:PDF(881.4KB)

Improved Constructions for Query-Efficient Locally Decodable Codes of Subexponential Length
Toshiya ITOH Yasuhiro SUZUKI 
Publication:   IEICE TRANSACTIONS on Information and Systems
Publication Date: 2010/02/01
Vol. E93-D  No. 2  pp. 263-270
Type of Manuscript:  Special Section PAPER (Special Section on Foundations of Computer Science)
Category: 
Keyword: 
locally decodable codesS-matching vectors, S-decoding polynomialsperfectly smooth decodersprivate information retrieval
 Summary | Full Text:PDF(273.4KB)

Approximation Algorithms for the Highway Problem under the Coupon Model
Ryoso HAMANE Toshiya ITOH Kouhei TOMITA 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2009/08/01
Vol. E92-A  No. 8  pp. 1779-1786
Type of Manuscript:  Special Section PAPER (Special Section on Discrete Mathematics and Its Applications)
Category: Theory
Keyword: 
line highway problemcycle highway problemmulti-valuationssingle-valuation
 Summary | Full Text:PDF(429.5KB)

Approximation Preserving Reductions among Item Pricing Problems
Ryoso HAMANE Toshiya ITOH Kouhei TOMITA 
Publication:   IEICE TRANSACTIONS on Information and Systems
Publication Date: 2009/02/01
Vol. E92-D  No. 2  pp. 149-157
Type of Manuscript:  Special Section PAPER (Special Section on Foundations of Computer Science)
Category: 
Keyword: 
item pricing problemapproximation preserving reductionsprice modelsselfloops
 Summary | Full Text:PDF(489.2KB)

Improved Approximation Algorithms for Item Pricing with Bounded Degree and Valuation
Ryoso HAMANE Toshiya ITOH 
Publication:   IEICE TRANSACTIONS on Information and Systems
Publication Date: 2008/02/01
Vol. E91-D  No. 2  pp. 187-199
Type of Manuscript:  Special Section PAPER (Special Section on Foundations of Computer Science)
Category: Approximation Algorithms
Keyword: 
item pricingapproximation algorithmpseudodegreevaluation ratio
 Summary | Full Text:PDF(302.1KB)

Competitive Analysis of Multi-Queue Preemptive QoS Algorithms for General Priorities
Toshiya ITOH Noriyuki TAKAHASHI 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2006/05/01
Vol. E89-A  No. 5  pp. 1186-1197
Type of Manuscript:  Special Section PAPER (Special Section on Discrete Mathematics and Its Applications)
Category: 
Keyword: 
quality of service (QoS)multi-queue switchesmulti-prioritypreemptioncompetitive ratio
 Summary | Full Text:PDF(314.2KB)

Improved Lower Bounds for Competitive Ratio of Multi-Queue Switches in QoS Networks
Toshiya ITOH Takanobu NAGUMO 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2005/05/01
Vol. E88-A  No. 5  pp. 1155-1165
Type of Manuscript:  Special Section PAPER (Special Section on Discrete Mathematics and Its Applications)
Category: 
Keyword: 
quality of service (QoS)multi-queue switchmulti-priority modelcompetitive ratio
 Summary | Full Text:PDF(215.6KB)

Constructing Families of ε-Approximate k-Wise Independent Permutations
Toshiya ITOH Yoshinori TAKEI Jun TARUI 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2004/05/01
Vol. E87-A  No. 5  pp. 993-1003
Type of Manuscript:  Special Section PAPER (Special Section on Discrete Mathematics and Its Applications)
Category: 
Keyword: 
k-wise independenceε-approximatepermutation familiesprobabilistic methodslinear algebra methods
 Summary | Full Text:PDF(268.6KB)

A Note on the Relationships among Certified Discrete Log Cryptosystems
Eikoh CHIDA Toshiya ITOH Hiroki SHIZUYA 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2003/05/01
Vol. E86-A  No. 5  pp. 1198-1202
Type of Manuscript:  Special Section PAPER (Special Section on Discrete Mathematics and Its Applications)
Category: 
Keyword: 
certified discrete logarithm problemorderprimitive rootprobabilistic reducibilitydeterministic reducibility
 Summary | Full Text:PDF(222KB)

Min-Wise Independence vs. 3-Wise Independence
Toshiya ITOH 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2002/05/01
Vol. E85-A  No. 5  pp. 957-966
Type of Manuscript:  Special Section PAPER (Special Section on Discrete Mathematics and Its Applications)
Category: 
Keyword: 
min-wise independencepairwise independence3-wise independencesearch engine
 Summary | Full Text:PDF(242.2KB)

On Lower Bounds for the Communication Complexity of Private Information Retrieval
Toshiya ITOH 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2001/01/01
Vol. E84-A  No. 1  pp. 157-164
Type of Manuscript:  Special Section PAPER (Special Section on Cryptography and Information Security)
Category: 
Keyword: 
private information retrievalcommunication complexitylinear typemultilinear typeaffine type
 Summary | Full Text:PDF(230.3KB)

Constructing an Optimal Family of Min-Wise Independent Permutations
Yoshinori TAKEI Toshiya ITOH Takahiro SHINOZAKI 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2000/04/25
Vol. E83-A  No. 4  pp. 747-755
Type of Manuscript:  PAPER
Category: Algorithms and Data Structures
Keyword: 
min-wise independencepermutationsoptimal boundp-samplability
 Summary | Full Text:PDF(490.1KB)

A General Construction of Min-Wise Independent Permutations
Yoshinori TAKEI Toshiya ITOH 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2000/04/25
Vol. E83-A  No. 4  pp. 646-655
Type of Manuscript:  Special Section PAPER (Special Section on Discrete Mathematics and Its Applications)
Category: 
Keyword: 
min-wise independencepermutationsgeneral construction
 Summary | Full Text:PDF(420.8KB)

Approximating the Maximum Weight of Linear Codes is APX-Complete
Toshiya ITOH 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2000/04/25
Vol. E83-A  No. 4  pp. 606-613
Type of Manuscript:  Special Section PAPER (Special Section on Discrete Mathematics and Its Applications)
Category: 
Keyword: 
approximation algorithmsAPX-completemaximum weightlinear codes
 Summary | Full Text:PDF(332.8KB)

Efficient Private Information Retrieval
Toshiya ITOH 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 1999/01/25
Vol. E82-A  No. 1  pp. 11-20
Type of Manuscript:  Special Section PAPER (Special Section on Cryptography and Information Security)
Category: 
Keyword: 
information retrievalprivacycommunication complexitytime complexitycovering codes
 Summary | Full Text:PDF(215.3KB)

On the Power of Self-Testers and Self-Correctors
Hiroyoshi MORI Toshiya ITOH 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 1997/01/25
Vol. E80-A  No. 1  pp. 98-106
Type of Manuscript:  Special Section PAPER (Special Section on Cryptography and Information Security)
Category: 
Keyword: 
checkersself-testersself-correctorsoneway permutationsself-tester/corrector pairs
 Summary | Full Text:PDF(681.9KB)

On the Oracle Entropy and the Average Case Oracle Measure of Knowledge Complexity
Toshiya ITOH 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 1997/01/25
Vol. E80-A  No. 1  pp. 90-97
Type of Manuscript:  Special Section PAPER (Special Section on Cryptography and Information Security)
Category: 
Keyword: 
statistical KCperfect KCoracle entropy measureaverage case oracle measure
 Summary | Full Text:PDF(612.7KB)

Checkers for Adaptive Programs
Toshiya ITOH Masahiro TAKEI 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 1995/01/25
Vol. E78-A  No. 1  pp. 42-50
Type of Manuscript:  Special Section PAPER (Special Section on Cryptography and Information Security)
Category: 
Keyword: 
program checkersfunction-restricted interactive proofsadaptive programscompetitive interactive proofsmultiple prover interactive proofs
 Summary | Full Text:PDF(790KB)

Alternative Necessary and Sufficient Conditions for Collision Intractable Hashing
Toshiya ITOH Kei HAYASHI 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 1995/01/25
Vol. E78-A  No. 1  pp. 19-26
Type of Manuscript:  Special Section PAPER (Special Section on Cryptography and Information Security)
Category: 
Keyword: 
claw-free pair permutationscollision intractable hash functionspseudo-permutationsdistinction intractability
 Summary | Full Text:PDF(683.5KB)

On the Knowledge Complexity of Arthur-Merlin Games
Toshiya ITOH Tatsuhiko KAKIMOTO 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 1994/01/25
Vol. E77-A  No. 1  pp. 56-64
Type of Manuscript:  Special Section PAPER (Special Section on Cryptography and Information Security)
Category: 
Keyword: 
interactive proof systemsknowledge complexityhintstrict oracleround complexity
 Summary | Full Text:PDF(863.6KB)

On the Knowledge Tightness of Zero-Knowledge Proofs
Toshiya ITOH Atsushi KAWAKUBO 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 1994/01/25
Vol. E77-A  No. 1  pp. 47-55
Type of Manuscript:  Special Section PAPER (Special Section on Cryptography and Information Security)
Category: 
Keyword: 
zero-knowledge proofsknowledge tightnessresettable simulationround complexity
 Summary | Full Text:PDF(802.3KB)

Demonstrating Possession without Revealing Factors
Hiroki SHIZUYA Kenji KOYAMA Toshiya ITOH 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 1994/01/25
Vol. E77-A  No. 1  pp. 39-46
Type of Manuscript:  Special Section PAPER (Special Section on Cryptography and Information Security)
Category: 
Keyword: 
zero-knowledge prooffactoringdiscrete logarithm
 Summary | Full Text:PDF(610KB)

Subliminal Channels for Transferring Signatures: Yet Another Cryptographic Primitive
Kouichi SAKURAI Toshiya ITOH 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 1994/01/25
Vol. E77-A  No. 1  pp. 31-38
Type of Manuscript:  Special Section PAPER (Special Section on Cryptography and Information Security)
Category: 
Keyword: 
subliminal channelsdigital signaturesFiat-Shamir scheme
 Summary | Full Text:PDF(766.5KB)

A Note on AM Languages Outside NP co-NP
Hiroki SHIZUYA Toshiya ITOH 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 1994/01/25
Vol. E77-A  No. 1  pp. 65-71
Type of Manuscript:  Special Section PAPER (Special Section on Cryptography and Information Security)
Category: 
Keyword: 
Arthur-Merlin gamegraph isomorphismgraph heterogeneity
 Summary | Full Text:PDF(587KB)

Constant Round Perfect ZKIP of Computational Ability
Toshiya ITOH Kouichi SAKURAI 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 1993/07/25
Vol. E76-A  No. 7  pp. 1225-1233
Type of Manuscript:  PAPER
Category: Information Security and Cryptography
Keyword: 
zero-knowledge interactive proof systemscomputational abilitypossession of knowledge
 Summary | Full Text:PDF(776.6KB)

On the Complexity of Composite Numbers
Toshiya ITOH Kenji HORIKAWA 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 1993/01/25
Vol. E76-A  No. 1  pp. 23-30
Type of Manuscript:  Special Section PAPER (Special Section on Cryptography and Information Security)
Category: 
Keyword: 
zero-knowledge interactive proof systemlanguage membershipcomposite numbers
 Summary | Full Text:PDF(739.6KB)

On the Complexity of Constant Round ZKIP of Possession of Knowledge
Toshiya ITOH Kouichi SAKURAI 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 1993/01/25
Vol. E76-A  No. 1  pp. 31-39
Type of Manuscript:  Special Section PAPER (Special Section on Cryptography and Information Security)
Category: 
Keyword: 
zero-knowledge interactive proof systempossession of knowledgeprobabilistic polynomial time algorithm
 Summary | Full Text:PDF(862.1KB)

Practical Consequences of the Discrepancy between Zero-Knowledge Protocols and Their Parallel Execution
Kouichi SAKURAI Toshiya ITOH 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 1993/01/25
Vol. E76-A  No. 1  pp. 14-22
Type of Manuscript:  Special Section PAPER (Special Section on Cryptography and Information Security)
Category: 
Keyword: 
zero-knowledge interactive proof systemthe Fiat-Shamir schemeno-transferable information
 Summary | Full Text:PDF(769.9KB)

On the Complexity of Hyperelliptic Discrete Logarithm Problem
Hiroki SHIZUYA Toshiya ITOH Kouichi SAKURAI 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 1991/08/25
Vol. E74-A  No. 8  pp. 2129-2135
Type of Manuscript:  Special Section PAPER (Special Issue on Cryptography and Information Security)
Category: 
Keyword: 
 Summary | Full Text:PDF(533.8KB)

Language Membership versus Possession of Knowledge in Constant Round ZKIP
Kouichi SAKURAI Toshiya ITOH 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 1991/08/25
Vol. E74-A  No. 8  pp. 2118-2123
Type of Manuscript:  Special Section PAPER (Special Issue on Cryptography and Information Security)
Category: 
Keyword: 
 Summary | Full Text:PDF(459.9KB)

A Group-Theoretic Interface to Random Self-Reducibility
Hiroki SHIZUYA Toshiya ITOH 
Publication:   IEICE TRANSACTIONS (1976-1990)
Publication Date: 1990/07/25
Vol. E73-E  No. 7  pp. 1087-1091
Type of Manuscript:  Special Section PAPER (Special Issue on Cryptography and Information Security)
Category: Authentication Techniques
Keyword: 
 Summary | Full Text:PDF(476.7KB)

An Attacking Method for Multiplicative Knapsack Type Public Key Cryptosystem Based on Finite Field
Kaoru KUROSAWA Toshiya ITOH Hiroo SHIGETA Shigeo TSUJII 
Publication:   IEICE TRANSACTIONS (1976-1990)
Publication Date: 1987/01/25
Vol. E70-E  No. 1  pp. 37-41
Type of Manuscript:  PAPER
Category: Information and Communication Theory
Keyword: 
 Summary | Full Text:PDF(327.7KB)