文字列情報処理の新展開－文字列組み合わせ論と高度データ構造技術の融合－

2015 Fiscal Year Annual Research Report

• Project/Area Number: 26280003
• Research Institution: Kyushu University
• Principal Investigator: 稲永 俊介 九州大学, システム情報科学研究科(研究院, 准教授 (60448404)
• Co-Investigator(Kenkyū-buntansha): 坂内 英夫 九州大学, システム情報科学研究科(研究院, 准教授 (20323644) ; 田部井 靖生 東京工業大学, 情報理工学(系)研究科, 研究員 (20589824)
• Project Period (FY): 2014-04-01 – 2017-03-31
• Keywords: アルゴリズム / データ構造 / 文字列組み合わせ論

Outline of Annual Research Achievements

本研究課題の目的は，大規模文字列データを対象とした効率的なデータ構造とアルゴリズムの開発である．本年度は，以下に示す (A)-(C) の重要研究テーマについて，主に以下の研究成果を達成した．
(A) テキスト圧縮・圧縮テキスト処理アルゴリズム (A-1) Lempel-Ziv78型テキスト圧縮手法 (LZ Double) の開発 (A-2) 連長圧縮文字列に対する漸増的編集距離計算アルゴリズム
(B) テキスト索引構造 (B-1) 省領域動的qグラム索引構造の開発 (B-2) 部分文字列同値性保存型照合アルゴリズム
(C) 文字列の規則性・繰り返し構造発見 (C-1) αギャップ付き反復・回文の高速計算アルゴリズムの開発 (C-2) 部分文字列同値性保存型照合に対する周期性補題の拡張 (C-3) アベリアン周期の逆問題と列挙問題のための高速アルゴリズム (C-4) 異回文分解の計算困難性の解析
これらの成果は，文字列に内在する組み合わせ的性質，および高度なデータ構造技術を活用することで達成された．また，これらの結果は，査読付き国際会議および査読付き国際論文誌にて発表済みである．

Current Status of Research Progress

1: Research has progressed more than it was originally planned.

Reason

本年度は，主に【研究実績の概要】で述べた研究成果について，査読付き国際会議に10件，査読付き国際ジャーナルに6件 (採択決定分含む) の論文を発表するに至った．これらの中には，STACS 2016 (33rd International Symposium on Theoretical Aspects of Computer Science), CPM 2015 (26th Annual Symposium on Combinatorial Pattern Matching) といった，当該分野の第１線で活躍する研究者が集う国際会議，Discrete Applied Mathematics，Theoretical Computer Science，Information Processing Letters といった定評のある国際論文誌が含まれており，質・量ともに当初の計画を上回る成果を得るに至っている．

Strategy for Future Research Activity

【現在までの進捗状況】で述べたように，これまでに，当初の計画以上の研究成果が得られている．今後も，このままの体制・方針で研究開発にまい進していく予定である．

Causes of Carryover

次年度は，本研究課題の最終年度であり，より多くの研究成果が得られることが予想される．国際会議，および国内研究集会における研究成果発表のための旅費確保のため，次年度に繰り越した次第である．また，実験のための，計算機を購入する予定である．

Expenditure Plan for Carryover Budget

上記の通り，主に旅費と計算機の購入に使用する予定である．

Research Products

• [Int'l Joint Research] TU Dortmund/Kiel University(Germany)
  • Country Name: Germany
  • Counterpart Institution: TU Dortmund/Kiel University
• [Int'l Joint Research] University of Warsaw(Poland)
  • Country Name: Poland
  • Counterpart Institution: University of Warsaw
• [Int'l Joint Research] University of Helsinki/University of Tampere(Finland)
  • Country Name: Finland
  • Counterpart Institution: University of Helsinki/University of Tampere
• [Int'l Joint Research] University of Sheffield/King's College London(英国)
  • Country Name: UNITED KINGDOM
  • Counterpart Institution: University of Sheffield/King's College London
• [Int'l Joint Research] University of Rouen(France)
  • Country Name: France
  • Counterpart Institution: University of Rouen
• [Journal Article] Faster Lyndon factorization algorithms for SLP and LZ78 compressed text (2016)
  • Author(s): Tomohiro I, Yuto Nakashima, Shunsuke Inenaga, Hideo Bannai, and Masayuki Takeda
  • Journal Title: Theoretical Computer Science Volume: 656(B) Pages: 215-224
  • DOI: 10.1016/j.tcs.2016.03.005
  • Peer Reviewed
• [Journal Article] Generalized pattern matching and periodicity under substring consistent equivalence relations (2016)
  • Author(s): Yoshiaki Matsuoka, Takahiro Aoki, Shunsuke Inenaga, Hideo Bannai, and Masayuki Takeda
  • Journal Title: Theoretical Computer Science Volume: 656(B) Pages: 225-233
  • DOI: 10.1016/j.tcs.2016.02.017
  • Peer Reviewed
• [Journal Article] Closed Factorization (2016)
  • Author(s): Golnaz Badkobeh, Hideo Bannai, Keisuke Goto, Tomohiro I, Costas S. Iliopoulos, Shunsuke Inenaga, Simon J. Puglisi, and Shiho Sugimoto
  • Journal Title: Discrete Applied Mathematics Volume: 212 Pages: 23-29
  • DOI: 10.1016/j.dam.2016.04.009
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Compacting a dynamic edit distance table by RLE compression (2016)
  • Author(s): Heikki Hyyro; and Shunsuke Inenaga
  • Journal Title: Proc. the 42nd International Conference on Current Trends in Theory and Practice of Computer Science (SOFSEM 2016) Volume: LNCS 9587 Pages: 302-313
  • DOI: 10.1007/978-3-662-49192-8_25
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Efficiently Finding All Maximal α-gapped Repeats (2016)
  • Author(s): Pawel Gawrychowski, Tomohiro I, Shunsuke Inenaga, Dominik Koeppl, and Florin Manea
  • Journal Title: Proc. the 33rd Symposium on Theoretical Aspects of Computer Science (STACS 2016) Volume: - Pages: 39:1-39:14
  • DOI: 10.4230/LIPIcs.STACS.2016.39
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Compressed automata for dictionary matching (2015)
  • Author(s): Tomohiro I, Takaaki Nishimoto, Shunsuke Inenaga, Hideo Bannai, and Masayuki Takeda
  • Journal Title: Theoretical Computer Science Volume: 578 Pages: 30-41
  • DOI: 10.1016/j.tcs.2015.01.019
  • Peer Reviewed
• [Journal Article] Constructing LZ78 Tries and Position Heaps in Linear Time for Large Alphabets (2015)
  • Author(s): Yuto Nakashima, Tomohiro I, Shunsuke Inenaga, Hideo Bannai and Masayuki Takeda
  • Journal Title: Information Processing Letters Volume: 115(9) Pages: 655-659
  • DOI: 10.1016/j.ipl.2015.04.002
  • Peer Reviewed
• [Journal Article] Dynamic Edit Distance Table under a General Weighted Cost Function (2015)
  • Author(s): Heikki Hyyro, Kazuyuki Narisawa, and Shunsuke Inenaga
  • Journal Title: Journal of Discrete Algorithms Volume: 34 Pages: 2-17
  • DOI: 10.1016/j.jda.2015.05.007
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Semi-dynamic compact index for short patterns and succinct van Emde Boas tree (2015)
  • Author(s): Yoshiaki Matsuoka, Tomohiro I, Shunsuke Inenaga, Hideo Bannai, and Masayuki Takeda
  • Journal Title: Proc. the 26th Annual Symposium on Combinatorial Pattern Matching (CPM 2015) Volume: LNCS 9133 Pages: 355-366
  • DOI: 10.1007/978-3-319-19929-0_30
  • Peer Reviewed
• [Journal Article] LZD Factorization: Simple and Practical Online Grammar Compression with Variable-to-Fixed Encoding (2015)
  • Author(s): Keisuke Goto, Hideo Bannai, Shunsuke Inenaga, and Masayuki Takeda
  • Journal Title: Proc. the 26th Annual Symposium on Combinatorial Pattern Matching (CPM 2015) Volume: LNCS 9133 Pages: 219-230
  • DOI: /10.1007/978-3-319-19929-0_19
  • Peer Reviewed
• [Journal Article] Diverse Palindromic Factorization is NP-Complete (2015)
  • Author(s): Hideo Bannai, Travis Gagie, Shunsuke Inenaga, Juha Kakkainen, Dominik Kempa, Marcin Piatkowski, Simon J. Puglisi, Shiho Sugimoto
  • Journal Title: Proc. the 19th International Conference on Developments in Language Theory (DLT 2015) Volume: LNCS 9168 Pages: 85-96
  • DOI: 10.1007/978-3-319-21500-6_6
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Computing Left-Right Maximal Generic Words (2015)
  • Author(s): Takaaki Nishimoto, Yuto Nakashima, Shunsuke Inenaga, Hideo Bannai and Masayuki Takeda
  • Journal Title: Proc. Prague Stringology Conference 2015 (PSC 2015) Volume: - Pages: 5-16
  • Peer Reviewed / Open Access
• [Journal Article] Efficient Algorithms for Longest Closed Factor Array (2015)
  • Author(s): Hideo Bannai, Shunsuke Inenaga, Tomasz Kociumaka, Arnaud Lefebvre, Jakub Radoszewski, Wojciech Rytter, Shiho Sugimoto and Tomasz Walen
  • Journal Title: Proc. the 22nd Symposium on String Processing and Information Retrieval (SPIRE 2015) Volume: LNCS 9309 Pages: 95-102
  • DOI: 10.1007/978-3-319-23826-5_10
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] A faster algorithm for computing maximal α-gapped repeats in a string (2015)
  • Author(s): Yuka Tanimura, Yuta Fujishige, Tomohiro I, Shunsuke Inenaga, Hideo Bannai and Masayuki Takeda
  • Journal Title: Proc. the 22nd Symposium on String Processing and Information Retrieval (SPIRE 2015) Volume: LNCS 9309 Pages: 124-136
  • DOI: 10.1007/978-3-319-23826-5_13
  • Peer Reviewed
• [Journal Article] Inferring Strings from Full Abelian Periods (2015)
  • Author(s): Makoto Nishida, Tomohiro I, Shunsuke Inenaga, Hideo Bannai and Masayuki Takeda
  • Journal Title: Proc. the 26th International Symposium on Algorithms and Computation (ISAAC 2015) Volume: LNCS 9472 Pages: 768-779
  • DOI: 10.1007/978-3-662-48971-0_64
  • Peer Reviewed / Int'l Joint Research
• [Presentation] Efficiently Finding All Maximal α-gapped Repeats (2016)
  • Author(s): Pawel Gawrychowski, Tomohiro I, Shunsuke Inenaga, Dominik Koeppl, and Florin Manea
  • Organizer: 33rd Symposium on Theoretical Aspects of Computer Science (STACS 2016)
  • Place of Presentation: Orleans, France
  • Year and Date: 2016-02-17 – 2016-02-20
  • Int'l Joint Research
• [Presentation] Compacting a dynamic edit distance table by RLE compression (2016)
  • Author(s): Heikki Hyyro and Shunsuke Inenaga
  • Organizer: 42nd International Conference on Current Trends in Theory and Practice of Computer Science (SOFSEM 2016)
  • Place of Presentation: Harrachov, Czech Republic
  • Year and Date: 2016-01-23 – 2016-01-28
  • Int'l Joint Research
• [Presentation] Inferring Strings from Full Abelian Periods (2015)
  • Author(s): Makoto Nishida, Tomohiro I, Shunsuke Inenaga, Hideo Bannai and Masayuki Takeda
  • Organizer: 26th International Symposium on Algorithms and Computation (ISAAC 2015)
  • Place of Presentation: Nagoya, Japan
  • Year and Date: 2015-12-09 – 2015-12-11
  • Int'l Joint Research
• [Presentation] Efficient Algorithms for Longest Closed Factor Array (2015)
  • Author(s): Hideo Bannai, Shunsuke Inenaga, Tomasz Kociumaka, Arnaud Lefebvre, Jakub Radoszewski, Wojciech Rytter, Shiho Sugimoto and Tomasz Walen
  • Organizer: 22nd Symposium on String Processing and Information Retrieval (SPIRE 2015)
  • Place of Presentation: London, UK
  • Year and Date: 2015-09-01 – 2015-09-04
  • Int'l Joint Research
• [Presentation] A faster algorithm for computing maximal α-gapped repeats in a string (2015)
  • Author(s): Yuka Tanimura, Yuta Fujishige, Tomohiro I, Shunsuke Inenaga, Hideo Bannai and Masayuki Takeda
  • Organizer: 22nd Symposium on String Processing and Information Retrieval (SPIRE 2015)
  • Place of Presentation: London, UK
  • Year and Date: 2015-09-01 – 2015-09-04
  • Int'l Joint Research
• [Presentation] Computing Left-Right Maximal Generic Words (2015)
  • Author(s): Takaaki Nishimoto, Yuto Nakashima, Shunsuke Inenaga, Hideo Bannai and Masayuki Takeda
  • Organizer: Prague Stringology Conference 2015 (PSC 2015)
  • Place of Presentation: Prague, Czech Republic
  • Year and Date: 2015-08-24 – 2015-08-26
  • Int'l Joint Research
• [Presentation] A Faster Longest Common Extension Algorithm on Compressed Strings and its Applications (2015)
  • Author(s): Shunsuke Inenaga
  • Organizer: Prague Stringology Conference 2015 (PSC 2015)
  • Place of Presentation: Prague, Czech Republic
  • Year and Date: 2015-08-24 – 2015-08-26
  • Int'l Joint Research / Invited
• [Presentation] Diverse Palindromic Factorization is NP-Complete (2015)
  • Author(s): Hideo Bannai, Travis Gagie, Shunsuke Inenaga, Juha Kärkkäinen, Dominik Kempa, Marcin Piatkowski, Simon J. Puglisi, Shiho Sugimoto
  • Organizer: 19th International Conference on Developments in Language Theory (DLT 2015)
  • Place of Presentation: Liverpool, UK
  • Year and Date: 2015-07-27 – 2015-07-30
  • Int'l Joint Research
• [Presentation] Semi-dynamic compact index for short patterns and succinct van Emde Boas tree (2015)
  • Author(s): Yoshiaki Matsuoka, Tomohiro I, Shunsuke Inenaga, Hideo Bannai, and Masayuki Takeda
  • Organizer: 26th Annual Symposium on Combinatorial Pattern Matching (CPM 2015)
  • Place of Presentation: Ischia, Italy
  • Year and Date: 2015-06-29 – 2015-07-01
  • Int'l Joint Research
• [Presentation] LZD Factorization: Simple and Practical Online Grammar Compression with Variable-to-Fixed Encoding (2015)
  • Author(s): Keisuke Goto, Hideo Bannai, Shunsuke Inenaga, and Masayuki Takeda
  • Organizer: 26th Annual Symposium on Combinatorial Pattern Matching (CPM 2015)
  • Place of Presentation: Ischia, Italy
  • Year and Date: 2015-06-29 – 2015-07-01
  • Int'l Joint Research
• [Remarks] Publication List of Shunsuke Inenaga
  • URL: https://str.i.kyushu-u.ac.jp/~inenaga/publications.html
• [Remarks] 研究者情報（九州大学）
  • URL: http://hyoka.ofc.kyushu-u.ac.jp/search/details/K003385/