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2020 Fiscal Year Annual Research Report

Research on algorithms and data structures for solving theoretically hard problems in practical time

Research Project

Project/Area Number 18H04091
Research InstitutionJapan Advanced Institute of Science and Technology

Principal Investigator

上原 隆平  北陸先端科学技術大学院大学, 先端科学技術研究科, 教授 (00256471)

Co-Investigator(Kenkyū-buntansha) 齋藤 寿樹  九州工業大学, 大学院情報工学研究院, 准教授 (00590390)
鈴木 顕  東北大学, 情報科学研究科, 准教授 (10723562)
川原 純  京都大学, 情報学研究科, 准教授 (20572473)
伊藤 健洋  東北大学, 情報科学研究科, 教授 (40431548)
山中 克久  岩手大学, 理工学部, 教授 (60508836)
吉仲 亮  東北大学, 情報科学研究科, 准教授 (80466424)
大舘 陽太  名古屋大学, 情報学研究科, 准教授 (80610196)
Project Period (FY) 2018-04-01 – 2023-03-31
Keywordsアルゴリズム / 離散構造 / 離散数学 / 計算量 / データ構造
Outline of Annual Research Achievements

本研究プロジェクトは,離散的な構造上における問題を中心に,その困難性に関する研究を行うプロジェクトであり,いくつかの方向性を持つ.まず解きたい問題を明確にし,定式化を行う.現実の問題をいかに抽象化・モデル化するかによって,問題の困難性は大きく異なって来る.次にその困難性の研究を行う.理論的に困難であれば,理論的な困難さの計算量的な根拠を示すことができる.一方,それが手に負えるとなれば,そこには具体的な解法,すなわちアルゴリズムが導かれる.こうして導かれた効率の良いアルゴリズムを実装し,実用的な速度で動作するかどうかを確認し,さらには元の現実の問題にフィードバックすることができる.
2020年度は新型コロナが急速に拡大し,当初計画していた対面での合宿形式の研究集会を十分に実施することができず,その中で研究方法も含めた模索が必要な年であった.行動が制限される中,研究者同士が柔軟に連絡を取りながら可能な範囲で共同研究を実施できた.理論的な困難性を示せた問題もあれば,効率の良いアルゴリズムを開発できた問題もある.また実際に実装して有効性を示せた問題もあった.
別紙に示す通り,2020年度は書籍3冊(研究書1冊と国際会議の会議録2冊)・査読付きのジャーナル論文18編・国際会議での発表27件を研究成果としてあげることができた.
また2020年の後半には,本研究プロジェクトのメンバーを中心として,学術変革(A)(研究課題名:社会変革の源泉となる革新的アルゴリズム基盤の創出と体系化)および学術変革(B)(研究課題名:組合せ遷移の展開に向けた計算機科学・工学・数学によるアプローチの融合)という大きな研究プロジェクトに採択され,本プロジェクトの研究の方向性をより大規模なものに発展させることができた.

Current Status of Research Progress
Current Status of Research Progress

2: Research has progressed on the whole more than it was originally planned.

Reason

2020年度は新型コロナの感染が拡大する中で,研究方法を模索しながらの共同研究となった.計画では,合宿形式の研究会を実施し,研究に関する問題意識の共有と,方向性の確認をする予定であったが,それは断念せざるを得なかった.その代わり,小規模にかつ継続的に個々のメンバーが連携をしながら研究活動を実施した.最終的には一堂に会しての大規模な合宿は一度も開催できず,状況に応じて可能な範囲で柔軟に共同研究を進めることとなった.そうした困難な状況であったにも関わらず,上記にデータを示した通り,2020年度は,本プロジェクトにおける研究成果は着実にあげることができた.しかしやや小規模なグループ単位での研究活動にとどまっているケースが多く,プロジェクト全体でのまとまった研究は持ち越しとなった.

Strategy for Future Research Activity

2021年以降は引き続き新型コロナ禍にあり,密な合宿形式の研究会は依然として実施が困難な状況が続いた.しかし,徐々にハイブリッド式の研究会にも慣れ,柔軟な運用で開催したり,個別にオンラインのツールを活用することで研究を続けた.怪我の功名として,こうした遠隔ツールを活用しての連携を深めながらの研究スタイルが確立されつつある.今後は新型コロナの状況を見ながらも,ポストコロナ,あるいはウィズコロナの研究スタイルを確立しつつ,継続して研究を進める方針である.
特にこうした社会状況を踏まえて,新たな問題意識や新たなビッグデータも蓄積しつつあるため,本プロジェクトのような,大規模な離散構造上の困難な問題への需要は高まっていると考えられる.そこで,こうした新たな問題も取り入れつつ,発展的に研究プロジェクトを進めていく方針である.

  • Research Products

    (49 results)

All 2021 2020

All Journal Article (18 results) (of which Int'l Joint Research: 10 results,  Peer Reviewed: 18 results,  Open Access: 12 results) Presentation (27 results) (of which Int'l Joint Research: 27 results) Book (3 results) Funded Workshop (1 results)

  • [Journal Article] Approximability of the independent feedback vertex set problem for bipartite graphs2021

    • Author(s)
      Tamura Yuma、Ito Takehiro、Zhou Xiao
    • Journal Title

      Theoretical Computer Science

      Volume: 849 Pages: 227~236

    • DOI

      10.1016/j.tcs.2020.10.026

    • Peer Reviewed
  • [Journal Article] Trichotomy for the reconfiguration problem of integer linear systems2021

    • Author(s)
      Kimura Kei、Suzuki Akira
    • Journal Title

      Theoretical Computer Science

      Volume: 856 Pages: 88~109

    • DOI

      10.1016/j.tcs.2020.12.025

    • Peer Reviewed
  • [Journal Article] Optimal reconfiguration of optimal ladder lotteries2021

    • Author(s)
      Yamanaka Katsuhisa、Horiyama Takashi、Wasa Kunihiro
    • Journal Title

      Theoretical Computer Science

      Volume: 859 Pages: 57~69

    • DOI

      10.1016/j.tcs.2021.01.009

    • Peer Reviewed
  • [Journal Article] Parameterized complexity of independent set reconfiguration problems2020

    • Author(s)
      Ito Takehiro、Kaminski Marcin、Ono Hirotaka、Suzuki Akira、Uehara Ryuhei、Yamanaka Katsuhisa
    • Journal Title

      Discrete Applied Mathematics

      Volume: 283 Pages: 336~345

    • DOI

      10.1016/j.dam.2020.01.022

    • Peer Reviewed / Int'l Joint Research
  • [Journal Article] Complexity of the Maximum k-Path Vertex Cover Problem2020

    • Author(s)
      MIYANO Eiji、SAITOH Toshiki、UEHARA Ryuhei、YAGITA Tsuyoshi、ZANDEN Tom C. van der
    • Journal Title

      IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences

      Volume: E103.A Pages: 1193~1201

    • DOI

      10.1587/transfun.2019DMP0014

    • Peer Reviewed / Int'l Joint Research
  • [Journal Article] Efficient Algorithm for Box Folding2020

    • Author(s)
      Mizunashi Koichi、Horiyama Takashi、Uehara Ryuhei
    • Journal Title

      Journal of Graph Algorithms and Applications

      Volume: 24 Pages: 89~103

    • DOI

      10.7155/jgaa.00520

    • Peer Reviewed / Open Access
  • [Journal Article] Rectangular Unfoldings of Polycubes2020

    • Author(s)
      L. Demaine Martin、A. Hearn Robert、Hoshido Junnosuke、Ku Jason、Uehara Ryuhei
    • Journal Title

      Journal of Information Processing

      Volume: 28 Pages: 841~845

    • DOI

      10.2197/ipsjjip.28.841

    • Peer Reviewed / Open Access / Int'l Joint Research
  • [Journal Article] Efficient Algorithm for 2 × n Map Folding with a Box-pleated Crease Pattern2020

    • Author(s)
      Jia Yiyang、Mitani Jun、Uehara Ryuhei
    • Journal Title

      Journal of Information Processing

      Volume: 28 Pages: 806~815

    • DOI

      10.2197/ipsjjip.28.806

    • Peer Reviewed / Open Access
  • [Journal Article] Valid Orderings of Layers When Simple-Folding a Map2020

    • Author(s)
      Jia Yiyang、Mitani Jun、Uehara Ryuhei
    • Journal Title

      Journal of Information Processing

      Volume: 28 Pages: 816~824

    • DOI

      10.2197/ipsjjip.28.816

    • Peer Reviewed / Open Access
  • [Journal Article] Minimum Forcing Sets for Single-vertex Crease Pattern2020

    • Author(s)
      Ouchi Koji、Uehara Ryuhei
    • Journal Title

      Journal of Information Processing

      Volume: 28 Pages: 800~805

    • DOI

      10.2197/ipsjjip.28.800

    • Peer Reviewed / Open Access
  • [Journal Article] Diameter of colorings under Kempe changes2020

    • Author(s)
      Bonamy Marthe、Heinrich Marc、Ito Takehiro、Kobayashi Yusuke、Mizuta Haruka、Muhlenthaler Moritz、Suzuki Akira、Wasa Kunihiro
    • Journal Title

      Theoretical Computer Science

      Volume: 838 Pages: 45~57

    • DOI

      10.1016/j.tcs.2020.05.033

    • Peer Reviewed / Open Access / Int'l Joint Research
  • [Journal Article] Complexity of the multi-service center problem2020

    • Author(s)
      Ito Takehiro、Kakimura Naonori、Kobayashi Yusuke
    • Journal Title

      Theoretical Computer Science

      Volume: 842 Pages: 18~27

    • DOI

      10.1016/j.tcs.2020.07.021

    • Peer Reviewed
  • [Journal Article] Parameterized Orientable Deletion2020

    • Author(s)
      Hanaka Tesshu、Katsikarelis Ioannis、Lampis Michael、Otachi Yota、Sikora Florian
    • Journal Title

      Algorithmica

      Volume: 82 Pages: 1909~1938

    • DOI

      10.1007/s00453-020-00679-6

    • Peer Reviewed / Open Access / Int'l Joint Research
  • [Journal Article] Independent Set Reconfiguration Parameterized by Modular-Width2020

    • Author(s)
      Belmonte Remy、Hanaka Tesshu、Lampis Michael、Ono Hirotaka、Otachi Yota
    • Journal Title

      Algorithmica

      Volume: 82 Pages: 2586~2605

    • DOI

      10.1007/s00453-020-00700-y

    • Peer Reviewed / Open Access / Int'l Joint Research
  • [Journal Article] Subgraph Isomorphism on Graph Classes that Exclude a Substructure2020

    • Author(s)
      Bodlaender Hans L.、Hanaka Tesshu、Kobayashi Yasuaki、Kobayashi Yusuke、Okamoto Yoshio、Otachi Yota、van der Zanden Tom C.
    • Journal Title

      Algorithmica

      Volume: 82 Pages: 3566~3587

    • DOI

      10.1007/s00453-020-00737-z

    • Peer Reviewed / Open Access / Int'l Joint Research
  • [Journal Article] Parameterized Complexity of Safe Set2020

    • Author(s)
      Belmonte Remy、Hanaka Tesshu、Katsikarelis Ioannis、Lampis Michael、Ono Hirotaka、Otachi Yota
    • Journal Title

      Journal of Graph Algorithms and Applications

      Volume: 24 Pages: 215~245

    • DOI

      10.7155/jgaa.00528

    • Peer Reviewed / Open Access / Int'l Joint Research
  • [Journal Article] K3 Edge Cover Problem in a Wide Sense2020

    • Author(s)
      Chiba Kyohei、Belmonte Remy、Ito Hiro、Lampis Michael、Nagao Atsuki、Otachi Yota
    • Journal Title

      Journal of Information Processing

      Volume: 28 Pages: 849~858

    • DOI

      10.2197/ipsjjip.28.849

    • Peer Reviewed / Open Access / Int'l Joint Research
  • [Journal Article] Token Sliding on Split Graphs2020

    • Author(s)
      Belmonte Remy、Kim Eun Jung、Lampis Michael、Mitsou Valia、Otachi Yota、Sikora Florian
    • Journal Title

      Theory of Computing Systems

      Volume: 65 Pages: 662~686

    • DOI

      10.1007/s00224-020-09967-8

    • Peer Reviewed / Open Access / Int'l Joint Research
  • [Presentation] Mathematical Characterizations and Computational Complexity of Anti-Slide Puzzles2021

    • Author(s)
      Ko Minamisawa, Ryuhei Uehara, Masao Hara
    • Organizer
      WALCOM 2021
    • Int'l Joint Research
  • [Presentation] Cyclic Shift Problems on Graphs2021

    • Author(s)
      Giovanni Viglietta, Ryuhei Uehara, Kwon Kham Sai
    • Organizer
      WALCOM 2021
    • Int'l Joint Research
  • [Presentation] Efficient Enumeration of Non-isomorphic Distance-Hereditary Graphs and Ptolemaic Graphs2021

    • Author(s)
      Kazuaki Yamazaki, Mengze Qian, Ryuhei Uehara
    • Organizer
      WALCOM 2021
    • Int'l Joint Research
  • [Presentation] Fixed-Treewidth-Efficient Algorithms for Edge-Deletion to Interval Graph Classes2021

    • Author(s)
      Toshiki Saitoh, Ryo Yoshinaka, Hans L. Bodlaender
    • Organizer
      WALCOM 2021
    • Int'l Joint Research
  • [Presentation] Efficient Folding Algorithms for Regular Polyhedra2020

    • Author(s)
      Tonan Kamata, Akira Kadoguchi, Takashi Horiyama, Ryuhei Uehara
    • Organizer
      CCCG 2020
    • Int'l Joint Research
  • [Presentation] Gathering on a Circle with Limited Visibility by Anonymous Oblivious Robots2020

    • Author(s)
      Giuseppe Antonio Di Luna, Ryuhei Uehara, Giovanni Viglietta, Yukiko Yamauchi
    • Organizer
      DISC 2020
    • Int'l Joint Research
  • [Presentation] Reconfiguration of Spanning Trees with Many or Few Leaves2020

    • Author(s)
      Nicolas Bousquet, Takehiro Ito, Yusuke Kobayashi, Haruka Mizuta, Paul Ouvrard, Akira Suzuki, Kunihiro Wasa
    • Organizer
      ESA 2020
    • Int'l Joint Research
  • [Presentation] Minimization and Parameterized Variants of Vertex Partition Problems on Graphs2020

    • Author(s)
      Yuma Tamura, Takehiro Ito, Xiao Zhou
    • Organizer
      ISAAC 2020
    • Int'l Joint Research
  • [Presentation] Fixed-Parameter Algorithms for Graph Constraint Logic2020

    • Author(s)
      Tatsuhiko Hatanaka, Felix Hommelsheim, Takehiro Ito, Yusuke Kobayashi, Moritz Muhlenthaler, Akira Suzuki
    • Organizer
      IPEC 2020
    • Int'l Joint Research
  • [Presentation] Hedonic Seat Arrangement Problems2020

    • Author(s)
      Hans L. Bodlaender, Tesshu Hanaka, Lars Jaffke, Hirotaka Ono, Yota Otachi, Tom C. van der Zanden
    • Organizer
      AAMAS 2020
    • Int'l Joint Research
  • [Presentation] A Survey on Spanning Tree Congestion2020

    • Author(s)
      Yota Otachi
    • Organizer
      Treewidth, Kernels, and Algorithms 2020
    • Int'l Joint Research
  • [Presentation] Grundy Distinguishes Treewidth from Pathwidth2020

    • Author(s)
      Remy Belmonte, Eun Jung Kim, Michael Lampis, Valia Mitsou, Yota Otachi
    • Organizer
      ESA 2020
    • Int'l Joint Research
  • [Presentation] Sublinear-Space Lexicographic Depth-First Search for Bounded Treewidth Graphs and Planar Graphs2020

    • Author(s)
      Taisuke Izumi, Yota Otachi
    • Organizer
      ICALP 2020
    • Int'l Joint Research
  • [Presentation] Parameterized Complexity of (A,l)-Path Packing2020

    • Author(s)
      Remy Belmonte, Tesshu Hanaka, Masaaki Kanzaki, Masashi Kiyomi, Yasuaki Kobayashi, Yusuke Kobayashi, Michael Lampis, Hirotaka Ono, Yota Otachi
    • Organizer
      IWOCA 2020
    • Int'l Joint Research
  • [Presentation] Parameterized Complexity of Graph Burning2020

    • Author(s)
      Yasuaki Kobayashi, Yota Otachi
    • Organizer
      IPEC 2020
    • Int'l Joint Research
  • [Presentation] Linear-Time Recognition of Double-Threshold Graphs2020

    • Author(s)
      Yusuke Kobayashi, Yoshio Okamoto, Yota Otachi, Yushi Uno
    • Organizer
      WG 2020
    • Int'l Joint Research
  • [Presentation] Enumerating All Subgraphs Under Given Constraints Using Zero-Suppressed Sentential Decision Diagrams2020

    • Author(s)
      Yu Nakahata, Masaaki Nishino, Jun Kawahara, Shin-ichi Minato
    • Organizer
      SEA 2020
    • Int'l Joint Research
  • [Presentation] Decremental Optimization of Dominating Sets Under the Reconfiguration Framework2020

    • Author(s)
      Alexandre Blanche, Haruka Mizuta, Paul Ouvrard, Akira Suzuki
    • Organizer
      IWOCA 2020
    • Int'l Joint Research
  • [Presentation] DAWGs for Parameterized Matching: Online Construction and Related Indexing Structures2020

    • Author(s)
      Katsuhito Nakashima, Noriki Fujisato, Diptarama Hendrian, Yuto Nakashima, Ryo Yoshinaka, Shunsuke Inenaga, Hideo Bannai, Ayumi Shinohara, Masayuki Takeda
    • Organizer
      CPM 2020
    • Int'l Joint Research
  • [Presentation] Grammar Compression with Probabilistic Context-Free Grammar2020

    • Author(s)
      Hiroaki Naganuma, Diptarama Hendrian, Ryo Yoshinaka, Ayumi Shinohara, Naoki Kobayashi
    • Organizer
      DCC 2020
    • Int'l Joint Research
  • [Presentation] AOBA: An Online Benchmark Tool for Algorithms in Stringology2020

    • Author(s)
      Ryu Wakimoto, Satoshi Kobayashi, Yuki Igarashi, Davaajav Jargalsaikhan, Diptarama Hendrian, Ryo Yoshinaka, Ayumi Shinohara
    • Organizer
      SOFSEM 2020
    • Int'l Joint Research
  • [Presentation] An Extension of Linear-size Suffix Tries for Parameterized Strings2020

    • Author(s)
      Katsuhito Nakashima, Diptarama Hendrian, Ryo Yoshinaka, Ayumi Shinohara
    • Organizer
      SOFSEM 2020
    • Int'l Joint Research
  • [Presentation] Parallel Duel-and-Sweep Algorithm for the Order-Preserving Pattern Matching2020

    • Author(s)
      Davaajav Jargalsaikhan, Diptarama Hendrian, Ryo Yoshinaka, Ayumi Shinohara
    • Organizer
      SOFSEM 2020
    • Int'l Joint Research
  • [Presentation] Computing Covers Under Substring Consistent Equivalence Relations2020

    • Author(s)
      Natsumi Kikuchi, Diptarama Hendrian, Ryo Yoshinaka, Ayumi Shinohara
    • Organizer
      SPIRE 2020
    • Int'l Joint Research
  • [Presentation] Fast and Linear-Time String Matching Algorithms Based on the Distances of q-Gram Occurrences2020

    • Author(s)
      Satoshi Kobayashi, Diptarama Hendrian, Ryo Yoshinaka, Ayumi Shinohara
    • Organizer
      SEA 2020
    • Int'l Joint Research
  • [Presentation] A Polynomial Delay Algorithm for Enumerating 2-Edge-Connected Induced Subgraphs2020

    • Author(s)
      Yusuke Sano, Katsuhisa Yamanaka, Takashi Hirayama
    • Organizer
      FAW 2020
    • Int'l Joint Research
  • [Presentation] Floorplans with Walls2020

    • Author(s)
      Katsuhisa Yamanaka, Shin-Ichi Nakano
    • Organizer
      TAMC 2020
    • Int'l Joint Research
  • [Book] Proceedings of the 15th International Conference and Workshops2021

    • Author(s)
      Ryuhei Uehara, Seok-Hee Hong, Subhas C. Nandy
    • Total Pages
      345
    • Publisher
      Springer
    • ISBN
      978-3-030-68210-1
  • [Book] Introduction to Computational Origami - The World of New Computational Geometry2020

    • Author(s)
      Ryuhei Uehara
    • Total Pages
      217
    • Publisher
      Springer
    • ISBN
      978-981-15-4469-9
  • [Book] Proceedings of the 10th International Conference on Fun with Algorithms2020

    • Author(s)
      Martin Farach-Colton, Giuseppe Prencipe, Ryuhei Uehara
    • Total Pages
      416
    • Publisher
      Schloss Dagstuhl
    • ISBN
      978-3-95977-145-0
  • [Funded Workshop] The 15th International Conference and Workshops on Algorithms and Computing (WALCOM 2021)2021

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Published: 2022-12-28  

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