圧縮文字列上の高速パターン列挙に関する基盤技術開発

2013 Fiscal Year Annual Research Report

• Project/Area Number: 12J06417
• Research Institution: Kyushu University
• Principal Investigator: 井 智弘 九州大学, 大学院・システム情報科学研究院, 特別研究員(PD)
• Keywords: 圧縮文字列処理 / 文字列中の規則性発見

Research Abstract

本年度は, 本研究テーマの一つの集大成として, 圧縮された文字列データから規則性をもった部分文字列を高速に計算・列挙する手法を開発した. 繰り返し構造や回文構造といった文字列の規則性の発見は文字列処理の基礎であり, また, ゲノムデータの解析などに応用出来る. 圧縮文字列処理では展開文字列長に比例する計算資源を用いないことを目標としており, そのため圧縮文字列を全て展開せずに処理しなければいけないという難しさがあるが, 解の列挙においてはさらに出力の仕方も問題になる. 単純に出力すると出力サイズに比例する時間を避ける事ができず, 今回の出力である繰り返し構造や回文構造の数は展開文字列長に比例するためである. 本手法では, 圧縮された文字列を展開する事無く処理を行い, かつ, 出力の圧縮表現を計算することでこの問題を回避した. これにより, ゲノムデータなどの大規模文字列データも, それが良く圧縮されているならば省領域かつ高速に規則性を発見することが出来る. この結果は38th International Symposium on Mathematical Foundations of Computer Science (MFCS2013)に採択され発表を行った.
また, 圧縮された文字列上の組み合わせ的性質を探る研究として圧縮文字列とLyndon文字列との関連性を探った. Lyndon文字列およびそれを基にしたLyndon分解は代数学と深く関連しており古くから知られているが, 近年はアルゴリズムへの応用も注目されている. 申請者らは24th Annual Symposium on Combinatorial Pattern Matching (CPM2013)と20th Symposium on String Processing and Information Retrieval (SPIRE 2013)において圧縮文字列からLyndon分解を効率的に求めるアルゴリズムを開発した. その過程において, Lyndon分解の項数が文法圧縮サイズの下界になっているという興味深い知見を得ている.

Strategy for Future Research Activity

(抄録なし)

Research Products

• [Journal Article] Faster Sparse Suffix Sorting (2014)
  • Author(s): Tomohiro I, Juha Kärkainen and Dominik Kempa
  • Journal Title: In Proc. the 31st Symposium on Theoretical Aspects of Computer Science (STACS 2014) Pages: 386-396
  • Peer Reviewed
• [Journal Article] Faster Compact On-Line Lempel-Ziv Factorization (2014)
  • Author(s): Jun-ichi Yamamoto, Tomohiro I, Hideo Bannai, Shunsuke Inenaga and Masayuki Takeda
  • Journal Title: In Proc. the 31st Symposium on Theoretical Aspects of Computer Science (STACS 2014) Pages: 675-686
  • Peer Reviewed
• [Journal Article] Computing palindromic factorizations and palindromic covers on-line (2014)
  • Author(s): Tomohiro I, Shiho Sugimoto, Shunsuke Inenaga, Hideo Bannai and Masayuki Takeda
  • Journal Title: In proc. the 25th Annual Symposium on Combinatorial Pattern Matching (CPM 2014) Volume: (To appear)
  • Peer Reviewed
• [Journal Article] Palindrome pattern matching (2013)
  • Author(s): Tomohiro I, Shunsuke Inenaga and Masayuki Takeda
  • Journal Title: Theoretical Computer Science Volume: 483 Pages: 162-170
  • Peer Reviewed
• [Journal Article] Inferring Strings from Suffix Trees and Links on a Binary Alphabet (2013)
  • Author(s): Tomohiro I, Shunsuke Inenaga, Hideo Bannai and Masayuki Takeda
  • Journal Title: Discrete Applied Mathematics Volume: 163(3) Pages: 316-325
  • Peer Reviewed
• [Journal Article] Efficient Lyndon factorization of grammar compressed text (2013)
  • Author(s): Tomohiro I, Yuto Nakashima, Shunsuke Inenaga, Hideo Bannai and Masayuki Takeda
  • Journal Title: In Proc. the 24th Annual Symposium on Combinatorial Pattern Matching (CPM 2013) Volume: LNCS 7922 Pages: 153-164
  • Peer Reviewed
• [Journal Article] Compressed Automata for Dictionary Matching (2013)
  • Author(s): Tomohiro I, Takaaki Nishimoto, Shunsuke Inenaga, Hideo Bannai and Masayuki Takeda
  • Journal Title: In Proc. the 18th International Conference on Implementation and Application of Automata (CIAA 2013) Volume: LNCS 7982 Pages: 319-330
  • Peer Reviewed
• [Journal Article] Detecting regularities on grammar-compressed strings (2013)
  • Author(s): Tomohiro I, Wataru Matsubara, Kouji Shimohira, Shunsuke Inenaga, Hideo Bannai, Masayuki Takeda, Kazuyuki Narisawa and Ayumi Shinohara
  • Journal Title: In Proc. the 38th International Symposium on Mathematical Foundations of Computer Science (MFCS 2013) Volume: LNCS 8087 Pages: 571-582
  • Peer Reviewed
• [Journal Article] Computing Reversed Lempel-Ziv Factorization Online (2013)
  • Author(s): Shiho Sugimoto, Tomohiro I, Shunsuke Inenaga, Hideo Bannai and Masayuki Takeda
  • Journal Title: In Proc. The Prague Stringology Conference (PSC 2013) Pages: 107-118
  • Peer Reviewed
• [Journal Article] Faster Lyndon factorization algorithms for SLP and 1278 compressed text (2013)
  • Author(s): Tomohiro I, Yuto Nakashima, Shunsuke Inenaga, Hideo Bannai and Masayuki Takeda
  • Journal Title: In Proc. the 20th Symposium on String Processing and Information Retrieval (SPIRE 2013) Volume: LNCS 8214 Pages: 174-185
  • Peer Reviewed
• [Presentation] Faster Compact On-Line Lempel-Ziv Factorization (2014)
  • Author(s): Jun-ichi Yamamoto, Tomiro I, Hideo Bannai, Shunsuke Inenaga and Masayuki Takeda
  • Organizer: the 31st Symposium on Theoretical Aspects of Computer Science (STACS 2014)
  • Place of Presentation: Lyon, France
  • Year and Date: 2014-03-08
• [Presentation] Faster Sparse Suffix Sorting (2014)
  • Author(s): Tomohiro I, Juha Kärkkäinen and Dominik Kempa
  • Organizer: the 31st Symposium on Theoretical Aspects of Computer Science (STACS 2014)
  • Place of Presentation: Lyon, France
  • Year and Date: 2014-03-06
• [Presentation] 回文による文字列の分解と被覆 (2014)
  • Author(s): 杉本志穂, 井智弘, 稲永俊介, 坂内英夫, 竹田正幸
  • Organizer: 冬のLAシンポジウム2013
  • Place of Presentation: 日本, 京都
  • Year and Date: 2014-01-30
• [Presentation] LZ78圧縮されたテキストに対するLyndon分解アルゴリズ (2014)
  • Author(s): 井智弘, 中島祐人, 稲永俊介, 坂内英夫, 竹田正幸
  • Organizer: 冬のLAシンポジウム2013
  • Place of Presentation: 日本, 京都
  • Year and Date: 2014-01-30
• [Presentation] 省スペースオンラインLZ分解 (2014)
  • Author(s): 山本淳一, 井智弘, 坂内英夫, 稲永俊介, 竹田正幸
  • Organizer: 冬のLAシンポジウム2013
  • Place of Presentation: 日本, 京都
  • Year and Date: 2014-01-29
• [Presentation] Faster Compact On-Line Lempel-Ziv Factorization (2013)
  • Author(s): Tomohiro I
  • Organizer: the 8th Workshop on Compression, Text, and Algorithms (WCTA 2013)
  • Place of Presentation: Jerusalem, Israel
  • Year and Date: 2013-10-10
• [Presentation] Faster Lyndon factorization algorithms for SLP and LZ78 compressed text (2013)
  • Author(s): Tomohiro I, Yuto Nakashima, Shunsuke Inenaga, Hideo Bannai and Masayuki Takeda
  • Organizer: the 20th Symposium on String Processing and Information Retrieval (SPIRE 2013)
  • Place of Presentation: Jerusalem, Israel
  • Year and Date: 2013-10-08
• [Presentation] Computing Reversed Lempel-Ziv Factorization Online (2013)
  • Author(s): Shiho Sugimoto, Tomohiro I, Shunsuke Inenaga, Hideo Bannai and Masayuki Takeda
  • Organizer: the Prague Stringology Conference (PSC 2013)
  • Place of Presentation: Prague, Czech
  • Year and Date: 2013-09-03
• [Presentation] Detecting regularities on grammar-compressed strings (2013)
  • Author(s): Tomohiro I, Wataru Matsubara, Kouji Shimohira, Shunsuke Inenaga, Hideo Bannai, Masayuki Takeda, Kazuyuki Narisawa and Ayumi Shinohara
  • Organizer: the 38th International Symposium on Mathematic al Foundations of Computer Science (MFCS 2013)
  • Place of Presentation: Klosterneuburg, Austria
  • Year and Date: 2013-08-27
• [Presentation] Lyndon分解の逆問題 (2013)
  • Author(s): 中島祐人, 岡部駿志, 井智弘, 稲永俊介, 坂内英夫, 竹田正幸
  • Organizer: 夏のLAシンポジウム2013
  • Place of Presentation: 日本, 福岡
  • Year and Date: 2013-07-17
• [Presentation] Compressed Automata for Dictionary Matching (2013)
  • Author(s): Tomohiro I, Takaaki Nishimoto, Shunsuke Inenaga, Hideo Bannai and Masayuki Takeda
  • Organizer: the 18th International Conference on Implementa tion and Application of Automata (CIAA 2013)
  • Place of Presentation: Halifax, Nova Scotia, Canada
  • Year and Date: 2013-07-16
• [Presentation] Efficient Lyndon factorization of grammar compressed text (2013)
  • Author(s): Tomohiro I, Yuto Nakashima, Shunsuke Inenaga, Hideo Bannai and Masayuki Takeda
  • Organizer: the 24th Annual Symposium on Combinatorial Pattern Matchine (CPM 2013)
  • Place of Presentation: Bad Herrenalb, Germany
  • Year and Date: 2013-06-19