Doctor of Engineering, 東北大学

Theory of informatics, algorithm, automata, information retrieval, parallel algorithm

Information security, Information Security

1985, Tohoku University, Graduate School, Division of Engineering

1980, Shinshu University, Faculty of Engineering

Substring Searchable Symmetric Encryption Based on an Improved DAWG
Hiroaki Yamamoto, Ryosuke Oda, Yoshihiro Wachi, Hiroshi Fujiwara
IEICE Transaction on Fundamentals, Vol.E105-A(No.12), 1578-1590, Dec. 2022, Refereed, Not invited
Lead

The Huffuman Tree Problem with Upper Bounded Linear Functions
Hiroshi Fujiwara, Yuichi Shirai, Hiroaki Yamamoto
IEICE Trans. on Inf. & Syst., Vol.E105-D(No.05), 474-480, Mar. 2022, Refereed

Asymptotic Approximation Ratios for Certain Classes of Online Bin Packing Algorithms
Hiroshi Fujiwara, Yuta Wanikawa, Hiroaki Yamamoto
IEICE Trans. on Inf. & Syst., Vol.E104-D(No.03), 362-369, Mar. 2021, Refereed

A New Finite Automaton Construction using a Prefix and a Suffix of Regular Expressions
Hiroaki Yamamoto, Hiroshi Fujiwara
IEICE Trans. on Inf. & Syst., E104-D(3), 2021, Refereed, Not invited
Lead, Corresponding

Space-Efficient and Secure Substring Searchable Symmetric Encryption Using an Improved DAWG
Hiroaki Yamamoto, Yoshihiro Wachi, Hiroshi Fujiwara
ProveSec2019, LNCS　11821, 130-148, Oct. 2019, Refereed

A faster algorithm for finding shortest substring matches of a regular expression
Hiroaki Yamamoto
Information Processing Letters, 143, 56-60, Dec. 2018, Refereed

Band-restricted diagonally dominant matrices: Computational complexity and application
Norikazu Takahashi, Daiki Hirata, Shuji Jimbo, Hiroaki Yamamoto
Journal of Computer and System Sciences, 101, 100-111, Nov. 2018, Refereed

Practical and Secure Searchable Symmetric Encryption with a Small Index
Ryuji Miyoshi, Hiroaki Yamamoto, Hiroshi Fujiwara, and Takashi Miyazaki
NordSec2017, LNCS 10674, 53-69, Nov. 2017, Refereed

Teaching Materials Using AR and VR for Learning the Usage of Oscilloscope
Takashi Miyazaki, Yusuke Ohira, Hiroaki Yamamoto, and Masaaki Nishi
Proc. of AVR 2017, LNCS 10325, 43-52, Jul. 2017, Refereed

Secure Automata-based Substring Search Scheme on Encrypted Data
Yamamoto,H.
Lecture Notes in Computer Science, IWSEC2016, LNCS 9836, 111-131, Sep. 2016, Refereed

A New Finite Automaton Construction for Regular Expressions
Hiroaki Yamamoto
Proc. of 6th Workshop on Non-Classical Models on Automata and Applications (NCMA 2014), NCMA 2014, pp.249-264, 2014, Refereed

Regular Expression Matching Algorithms using Dual Position Automata
Yamamoto, H.
JCMCC, (71), 103-125, 2009, Refereed

Bit-parallel Tree Pattern Matching Algorithms for Unordered Labeled Trees
Yamamoto, H.; Takenouchi, D.
Lecture Notes in Computer Science, (5664), 554-565, 2009, Refereed

Bit-Parallel Algorithms for Translating Regular Expressions into NFAs
Yamamoto, H.; Miyazaki, T.; Okamoto, M.
IEICE Trans. on Inf.&Syst., E90-D(2), 418-427, 2007

A new translation from semi-extended regular expressions into NFAs and its application to an approximate matching problem
Yamamoto, H
ALGORITHMS AND COMPUTATION, PROCEEDINGS, LNCS 2906, 158-167, 2003, Refereed

A fast bit-parallel algorithm for matching extended regular expressions
Yamamoto, H; Miyazaki, T
COMPUTING AND COMBINATORICS, PROCEEDINGS, 2697, 222-231, 2003, Refereed

A New Recognition Algorithm for Extended Regular Expressions
Yamamoto, H
ISAAC 2001, LNCS 2223, 257-267, 2001, Refereed

An Automata-based Recognition Algorithm for Semi-extended Regular Expressions
Yamamoto,　H.
MFCS 2000, LNCS 1893, 699-708, 2000, Refereed

On the Power of Input-Synchronized Alternating Finite Automata
Yamamoto, H
COMPUTING AND COMBINATORICS, PROCEEDINGS, 1858, 457-466, 2000, Refereed

An improved method to extract quasi-random sequences from generalized semi-random sources
Yamamoto, H; Kasuga, H
IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES, E82A(3), 512-519, 1999, Refereed

Optimal broadcasting in almost trees and partial k-trees
Dessmark, A; Lingas, A; Olsson, H; Yamamoto, H
STACS 98 - 15TH ANNUAL SYMPOSIUM ON THEORETICAL ASPECTS OF COMPUTER SCIENCE, LNCS 1373, 432-443, 1998, Refereed

On the power of alternation on reversal-bounded alternating Turing machines with a restriction
Yamamoto, H
Theoretical Computer Science, 180(1-2), 139-154, 1997, Refereed

On the power of reversals over the input tape of off-line Turing machines
Yamamoto, H
IEICE TRANSACTIONS ON INFORMATION AND SYSTEMS, E79D(11), 1495-1502, 1996, Refereed

Efficient Verifiable Dynamic Searchable Symmetric Encryption with a Tree-based Index
Kyohei Ozawa, Ryuji Miyoshi, Hiroaki Yamamoto
IWSEC2021, Sep. 2021

EATCS

pattern matching algorithm and its application

Secure and efficient searchable symmetric encryption