Toru FUJIWARA


Efficient Usage of Cover Free Families in Broadcast Encryption
Maki YOSHIDA Toru FUJIWARA 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2016/06/01
Vol. E99-A  No. 6  pp. 1216-1221
Type of Manuscript:  PAPER
Category: Cryptography and Information Security
Keyword: 
cover free familyefficiencybroadcast encryptionupper bound
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Determinacy and Subsumption of Single-Valued Bottom-Up Tree Transducers
Kenji HASHIMOTO Ryuta SAWADA Yasunori ISHIHARA Hiroyuki SEKI Toru FUJIWARA 
Publication:   IEICE TRANSACTIONS on Information and Systems
Publication Date: 2016/03/01
Vol. E99-D  No. 3  pp. 575-587
Type of Manuscript:  Special Section PAPER (Special Section on Foundations of Computer Science---Developments of the Theory of Algorithms and Computation---)
Category: 
Keyword: 
determinacysubsumptiontree transducer
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On the Impossibility of d-Multiplicative Non-perfect Secret Sharing
Maki YOSHIDA Toru FUJIWARA 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2015/02/01
Vol. E98-A  No. 2  pp. 767-770
Type of Manuscript:  LETTER
Category: Cryptography and Information Security
Keyword: 
secret sharingmultiplicativenon-perfectimpossibility
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Individual Restoration of Tampered Pixels for Statistical Fragile Watermarking
Maki YOSHIDA Kazuya OHKITA Toru FUJIWARA 
Publication:   IEICE TRANSACTIONS on Information and Systems
Publication Date: 2015/01/01
Vol. E98-D  No. 1  pp. 58-64
Type of Manuscript:  Special Section PAPER (Special Section on Enriched Multimedia)
Category: 
Keyword: 
watermarkingfragiletamperingdetectionrestorationmaximum length sequence code
 Summary | Full Text:PDF(3.4MB)

Decidability of the Security against Inference Attacks Using a Functional Dependency on XML Databases
Kenji HASHIMOTO Hiroto KAWAI Yasunori ISHIHARA Toru FUJIWARA 
Publication:   IEICE TRANSACTIONS on Information and Systems
Publication Date: 2012/05/01
Vol. E95-D  No. 5  pp. 1365-1374
Type of Manuscript:  Special Section PAPER (Special Section on Formal Approach)
Category: Database Security
Keyword: 
XML databaseinference attacksecurityverificationfunctional dependency
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A Recursive Method for Vector Generation in Non-increasing Order of Its Likelihood for All Binary Vectors and Its Application for Linear Block Code Decodings
Takuya KUSAKA Ryuhei YOKOYAMA Toru FUJIWARA 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2012/04/01
Vol. E95-A  No. 4  pp. 801-810
Type of Manuscript:  PAPER
Category: Coding Theory
Keyword: 
binary vectorrecursive algorithmMLDsoft-decisionenumeration
 Summary | Full Text:PDF(1010.6KB)

FOREWORD
Toru FUJIWARA 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2011/01/01
Vol. E94-A  No. 1  pp. 1-2
Type of Manuscript:  FOREWORD
Category: 
Keyword: 
 Summary | Full Text:PDF(145KB)

Toward Digital Watermarking for Cryptographic Data
Maki YOSHIDA Toru FUJIWARA 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2011/01/01
Vol. E94-A  No. 1  pp. 270-272
Type of Manuscript:  Special Section LETTER (Special Section on Cryptography and Information Security)
Category: 
Keyword: 
digital watermarkingcryptographic datadetectionvisibletrapdoor for removing
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The Vector Decomposition Problem
Maki YOSHIDA Shigeo MITSUNARI Toru FUJIWARA 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2010/01/01
Vol. E93-A  No. 1  pp. 188-193
Type of Manuscript:  Special Section PAPER (Special Section on Cryptography and Information Security)
Category: Mathematics
Keyword: 
computational problemvector decomposition problemcomputational Diffie-Hellman problemelliptic curvepairing
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Verification of the Security against Inference Attacks on XML Databases
Kenji HASHIMOTO Kimihide SAKANO Fumikazu TAKASUKA Yasunori ISHIHARA Toru FUJIWARA 
Publication:   IEICE TRANSACTIONS on Information and Systems
Publication Date: 2009/05/01
Vol. E92-D  No. 5  pp. 1022-1032
Type of Manuscript:  Special Section PAPER (Special Section on Formal Approach)
Category: Security
Keyword: 
XML databaseinference attacksecurityverification
 Summary | Full Text:PDF(814.8KB)

Flexible Timed-Release Encryption
Maki YOSHIDA Toru FUJIWARA 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2009/01/01
Vol. E92-A  No. 1  pp. 222-225
Type of Manuscript:  Special Section LETTER (Special Section on Cryptography and Information Security)
Category: 
Keyword: 
timed-release encryptiontime-server based approachglobal useflexibility
 Summary | Full Text:PDF(223.3KB)

Local Weight Distribution of the (256, 93) Third-Order Binary Reed-Muller Code
Kenji YASUNAGA Toru FUJIWARA Tadao KASAMI 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2007/03/01
Vol. E90-A  No. 3  pp. 698-701
Type of Manuscript:  LETTER
Category: Coding Theory
Keyword: 
local weight distributionminimal codewordReed-Muller codebinary shift
 Summary | Full Text:PDF(86KB)

A New Scheme to Realize the Optimum Watermark Detection for the Additive Embedding Scheme with the Spatial Domain
Takaaki FUJITA Maki YOSHIDA Toru FUJIWARA 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2007/01/01
Vol. E90-A  No. 1  pp. 216-225
Type of Manuscript:  Special Section PAPER (Special Section on Cryptography and Information Security)
Category: Application
Keyword: 
digital watermarkingadditive embedding schemeoptimum detectionNeyman-Pearson criterion
 Summary | Full Text:PDF(459KB)

A Private and Consistent Data Retrieval Scheme with Log-Squared Communication
Satoshi NAKAYAMA Maki YOSHIDA Shingo OKAMURA Toru FUJIWARA 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2007/01/01
Vol. E90-A  No. 1  pp. 204-215
Type of Manuscript:  Special Section PAPER (Special Section on Cryptography and Information Security)
Category: Application
Keyword: 
data retrievalprivacy of a usersecrecy of the databaseconsistency of answerscommunication complexity
 Summary | Full Text:PDF(412.2KB)

Security against Inference Attacks on Negative Information in Object-Oriented Databases
Yasunori ISHIHARA Shuichiro AKO Toru FUJIWARA 
Publication:   IEICE TRANSACTIONS on Information and Systems
Publication Date: 2005/12/01
Vol. E88-D  No. 12  pp. 2767-2776
Type of Manuscript:  PAPER
Category: Database
Keyword: 
object-oriented databaseauthorizationinference attacknegative information
 Summary | Full Text:PDF(411.9KB)

Unlinkable Delivery System for Interactive Dramas
Shingo OKAMURA Yoshiyuki KONISHI Maki YOSHIDA Toru FUJIWARA 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2005/01/01
Vol. E88-A  No. 1  pp. 262-269
Type of Manuscript:  Special Section PAPER (Special Section on Cryptography and Information Security)
Category: Application
Keyword: 
interactive dramadelivery controlprotection of privacypartially blind signature scheme
 Summary | Full Text:PDF(194.8KB)

Sufficient Conditions for Update Operations on Object-Oriented Databases to Preserve the Security against Inference Attacks
Yasunori ISHIHARA Kengo MORI Toru FUJIWARA 
Publication:   IEICE TRANSACTIONS on Information and Systems
Publication Date: 2003/10/01
Vol. E86-D  No. 10  pp. 2187-2197
Type of Manuscript:  PAPER
Category: Databases
Keyword: 
object-oriented databaseauthorizationinference attacksecurityincremental checking
 Summary | Full Text:PDF(337.6KB)

Analysis and Optimization of Kumar-Rajagopalan-Sahai Coding Constructions for Blacklisting Problem
Maki YOSHIDA Toru FUJIWARA 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2001/09/01
Vol. E84-A  No. 9  pp. 2338-2345
Type of Manuscript:  PAPER
Category: Information Security
Keyword: 
data securitybroadcast distribution systemcover-free familymaximum distance separable code
 Summary | Full Text:PDF(236.5KB)

Weight Distributions of the Coset Leaders of Some Reed-Muller Codes and BCH Codes
Masaya MAEDA Toru FUJIWARA 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2001/03/01
Vol. E84-A  No. 3  pp. 851-859
Type of Manuscript:  PAPER
Category: Coding Theory
Keyword: 
binary linear block codecosetcoset leaderweight distributionReed-Muller and BCH codes
 Summary | Full Text:PDF(365.5KB)

A Subscriber-Excluding and Traitor-Tracing Broadcast Distribution System
Maki YOSHIDA Toru FUJIWARA 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2001/01/01
Vol. E84-A  No. 1  pp. 247-255
Type of Manuscript:  Special Section PAPER (Special Section on Cryptography and Information Security)
Category: 
Keyword: 
broadcast distribution systemsubscriber-excludingpirate decodertraitor tracingElGamal cryptosystem
 Summary | Full Text:PDF(250.5KB)

The Optimal Sectionalized Trellises for the Generalized Version of Viterbi Algorithm of Linear Block Codes and Its Application to Reed-Muller Codes
Yuansheng TANG Toru FUJIWARA Tadao KASAMI 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2000/11/25
Vol. E83-A  No. 11  pp. 2329-2340
Type of Manuscript:  PAPER
Category: Coding Theory
Keyword: 
linear block codesectionalizationminimal sectionalized trellisgeneralized Viterbi algorithmcomputational complexity
 Summary | Full Text:PDF(508.3KB)

MAP and LogMAP Decoding Algorithms for Linear Block Codes Using a Code Structure
Yuichi KAJI Ryujiro SHIBUYA Toru FUJIWARA Tadao KASAMI Shu LIN 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2000/10/25
Vol. E83-A  No. 10  pp. 1884-1890
Type of Manuscript:  Special Section PAPER (Special Section on Information Theory and Its Applications)
Category: Coding Theory
Keyword: 
MAP decodingBCJR algorithmturbo codestrellis diagramlinear block codes
 Summary | Full Text:PDF(556.9KB)

Sufficient Conditions for Ruling-Out Useless Iterative Steps in a Class of Iterative Decoding Algorithms
Tadao KASAMI Yuansheng TANG Takuya KOUMOTO Toru FUJIWARA 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 1999/10/25
Vol. E82-A  No. 10  pp. 2061-2073
Type of Manuscript:  Special Section PAPER (Special Section on Information Theory and Its Applications)
Category: Coding Theory
Keyword: 
soft-decisioniterative decodingbinary block codesruling-out conditionsearly termination conditions
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A Method for Obtaining the Optimum Sectionalization of the RMLD Algorithm for Non-Linear Rectangular Codes
Yasuhiro MATSUMOTO Toru FUJIWARA 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 1999/10/25
Vol. E82-A  No. 10  pp. 2052-2060
Type of Manuscript:  Special Section PAPER (Special Section on Information Theory and Its Applications)
Category: Coding Theory
Keyword: 
maximum likelihood decodingrecursive maximum likelihood decodingrectangular codeoptimum sectionalizationdynamic programming approach
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A Recursive Maximum Likelihood Decoding Algorithm for Some Transitive Invariant Binary Block Codes
Tadao KASAMI Hitoshi TOKUSHIGE Toru FUJIWARA Hiroshi YAMAMOTO Shu LIN 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 1998/09/25
Vol. E81-A  No. 9  pp. 1916-1924
Type of Manuscript:  PAPER
Category: Information Theory and Coding Theory
Keyword: 
recursive maximum likelihood decodingtransitive invariant codesReed-Muller codesextended BCH codes
 Summary | Full Text:PDF(790.4KB)

Low Weight Subtrellises for Binary Linear Block Codes and Their Applications
Tadao KASAMI Takuya KOUMOTO Toru FUJIWARA Hiroshi YAMAMOTO Yoshihisa DESAKI Shu LIN 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 1997/11/25
Vol. E80-A  No. 11  pp. 2095-2103
Type of Manuscript:  Special Section PAPER (Special Section on Information Theory and Its Applications)
Category: Coding Theory
Keyword: 
subtrellis diagramlow weightbinary linear coderecursive decoding algorithmsubtrellis search
 Summary | Full Text:PDF(751.6KB)

An lmproved Method for Formal Security Verification of Cryptographic Protocols
Hajime WATANABE Toru FUJIWARA Tadao KASAMI 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 1996/07/25
Vol. E79-A  No. 7  pp. 1089-1096
Type of Manuscript:  PAPER
Category: Information Security
Keyword: 
authenticationcomputer securitycryptographic protocolprotocol verification
 Summary | Full Text:PDF(689.3KB)

The Weight Distributions of Cosets of the Second-Order Reed-Muller Code of Length 128 in the Third-Order Reed-Muller Code of Length 128
Tadao KASAMI Toru FUJIWARA Yoshihisa DESAKI 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 1996/04/25
Vol. E79-A  No. 4  pp. 600-608
Type of Manuscript:  PAPER
Category: Information Theory and Coding Theory
Keyword: 
linear block codesReed-Muller codescoset and weight distribution
 Summary | Full Text:PDF(632.2KB)

Average Complexity Evaluation of an MLD Algorithm Using the Trellis Structure for a Linear Block Code
Hidehisa NAGANO Toru FUJIWARA Tadao KASAMI 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 1995/09/25
Vol. E78-A  No. 9  pp. 1209-1214
Type of Manuscript:  Special Section LETTER (Special Section on Information Theory and Its Applications)
Category: 
Keyword: 
maximum likelihood decodinglinear block codeBCH codeReed-Muller codeL-section minimal trellis diagram
 Summary | Full Text:PDF(451KB)

A Method for Computing the Weight Distribution of a Block Code by Using Its Trellis Diagram
Yoshihisa DESAKI Toru FUJIWARA Tadao KASAMI 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 1994/08/25
Vol. E77-A  No. 8  pp. 1230-1237
Type of Manuscript:  Special Section PAPER (Special Section on Information Theory and Its Applications)
Category: 
Keyword: 
block codesweight distributiontrellis diagramBCH codes
 Summary | Full Text:PDF(693.2KB)

On Branch Labels of Parallel Components of the L-Section Minimal Trellis Diagrams for Binary Linear Block Codes
Tadao KASAMI Toru FUJIWARA Yoshihisa DESAKI Shu LIN 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 1994/06/25
Vol. E77-A  No. 6  pp. 1058-1068
Type of Manuscript:  PAPER
Category: Information Theory and Coding Theory
Keyword: 
linear block codestrellis diagramparallel structure and Reed-Muller codes
 Summary | Full Text:PDF(867KB)

On Structural Complexity of the L-Section Minimal Trellis Diagrams for Binary Linear Block Codes
Tadao KASAMI Toyoo TAKATA Toru FUJIWARA Shu LIN 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 1993/09/25
Vol. E76-A  No. 9  pp. 1411-1421
Type of Manuscript:  Special Section PAPER (Special Section on Information Theory and Its Applications)
Category: 
Keyword: 
linear codeblock codetrellis diagramReed-Muller code
 Summary | Full Text:PDF(819.9KB)

A System for Deciding the Security of Cryptographic Protocols
Hajime WATANABE Toru FUJIWARA Tadao KASAMI 
Publication:   IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 1993/01/25
Vol. E76-A  No. 1  pp. 96-103
Type of Manuscript:  Special Section PAPER (Special Section on Cryptography and Information Security)
Category: 
Keyword: 
computer securitycryptographic protocolprotocol verification
 Summary | Full Text:PDF(630.8KB)

Comparison of Aliasing Probability for Multiple MISRs and M-Stage MISRs with m Inputs
Kazuhiko IWASAKI Shou-Ping FENG Toru FUJIWARA Tadao KASAMI 
Publication:   IEICE TRANSACTIONS on Information and Systems
Publication Date: 1992/11/25
Vol. E75-D  No. 6  pp. 835-841
Type of Manuscript:  Special Section PAPER (Special Issue on Pacific Rim International Symposium on Fault Tolerant Systems)
Category: 
Keyword: 
BISTaliasing probabilitymultiple MISRM-stage MISR with m imputsbinary symmetric channel
 Summary | Full Text:PDF(578.4KB)

Cross-Over Component Code Construction for Multi-Level Block Modulation Codes
Tadao KASAMI Toyoo TAKATA Toru FUJIWARA Shu LIN 
Publication:   IEICE TRANSACTIONS (1976-1990)
Publication Date: 1990/10/25
Vol. E73-E  No. 10  pp. 1657-1665
Type of Manuscript:  Special Section PAPER (Special Issue on Communication Theory and Its Applications)
Category: Modulation and Demodulation
Keyword: 
 Summary | Full Text:PDF(734.8KB)