2 Search Results for "Inoue, Masashi"


Document
Self-Stabilizing Weakly Byzantine Perpetual Gathering of Mobile Agents

Authors: Jion Hirose, Ryota Eguchi, and Yuichi Sudo

Published in: LIPIcs, Volume 330, 4th Symposium on Algorithmic Foundations of Dynamic Networks (SAND 2025)


Abstract
We study the Byzantine gathering problem involving k mobile agents with unique identifiers (IDs), f of which are Byzantine. These agents start the execution of a common algorithm from (possibly different) nodes in an n-node network, potentially starting at different times. Once started, the agents operate in synchronous rounds. We focus on weakly Byzantine environments, where Byzantine agents can behave arbitrarily but cannot falsify their IDs. The goal is for all non-Byzantine agents to eventually terminate at a single node simultaneously. In this paper, we first prove two impossibility results: (1) for any number of non-Byzantine agents, no algorithm can solve this problem without global knowledge of the network size or the number of agents, and (2) no self-stabilizing algorithm exists if k ≤ 2f even with n, k, f, and the length Λ_g of the largest ID among IDs of non-Byzantine agents, where the self-stabilizing algorithm enables agents to gather starting from arbitrary (inconsistent) initial states. Next, based on these results, we introduce a perpetual gathering problem and propose a self-stabilizing algorithm for this problem. This problem requires that all non-Byzantine agents always be co-located from a certain time onwards. If the agents know Λ_g and upper bounds N, K, F on n, k, f, the proposed algorithm works in O(K⋅ F⋅ Λ_g⋅ X(N)) rounds, where X(n) is the time required to visit all nodes in a n-nodes network. Our results indicate that while no algorithm can solve the original self-stabilizing gathering problem for any k and f even with exact global knowledge of the network size and the number of agents, the self-stabilizing perpetual gathering problem can always be solved with just upper bounds on this knowledge.

Cite as

Jion Hirose, Ryota Eguchi, and Yuichi Sudo. Self-Stabilizing Weakly Byzantine Perpetual Gathering of Mobile Agents. In 4th Symposium on Algorithmic Foundations of Dynamic Networks (SAND 2025). Leibniz International Proceedings in Informatics (LIPIcs), Volume 330, pp. 13:1-13:18, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2025)


Copy BibTex To Clipboard

@InProceedings{hirose_et_al:LIPIcs.SAND.2025.13,
  author =	{Hirose, Jion and Eguchi, Ryota and Sudo, Yuichi},
  title =	{{Self-Stabilizing Weakly Byzantine Perpetual Gathering of Mobile Agents}},
  booktitle =	{4th Symposium on Algorithmic Foundations of Dynamic Networks (SAND 2025)},
  pages =	{13:1--13:18},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-368-3},
  ISSN =	{1868-8969},
  year =	{2025},
  volume =	{330},
  editor =	{Meeks, Kitty and Scheideler, Christian},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.SAND.2025.13},
  URN =		{urn:nbn:de:0030-drops-230662},
  doi =		{10.4230/LIPIcs.SAND.2025.13},
  annote =	{Keywords: Distributed algorithms, Byzantine environments, Gathering}
}
Document
Difficulties in Image Retrieval

Authors: Masashi Inoue

Published in: Dagstuhl Seminar Proceedings, Volume 8251, Contextual and Social Media Understanding and Usage (2009)


Abstract
The semantic gap is often regarded as a major problem in the field of image retrieval research. In this paper, I will show that there are other important topics that should be addressed for improving the image retrieval utility. Among them, the exploitation of limited information and motivating the use of images are considered to be central to the development of image retrieval.

Cite as

Masashi Inoue. Difficulties in Image Retrieval. In Contextual and Social Media Understanding and Usage. Dagstuhl Seminar Proceedings, Volume 8251, pp. 1-2, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2009)


Copy BibTex To Clipboard

@InProceedings{inoue:DagSemProc.08251.4,
  author =	{Inoue, Masashi},
  title =	{{Difficulties in Image Retrieval}},
  booktitle =	{Contextual and Social Media Understanding and Usage},
  pages =	{1--2},
  series =	{Dagstuhl Seminar Proceedings (DagSemProc)},
  ISSN =	{1862-4405},
  year =	{2009},
  volume =	{8251},
  editor =	{Susanne Boll and Mohan S. Kankanhalli and Gopal Pingali and Svetha Venkatesh},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/DagSemProc.08251.4},
  URN =		{urn:nbn:de:0030-drops-20199},
  doi =		{10.4230/DagSemProc.08251.4},
  annote =	{Keywords: Image retrieval, utility, user, scarcity, insufficiency}
}
  • Refine by Type
  • 2 Document/PDF
  • 1 Document/HTML

  • Refine by Publication Year
  • 1 2025
  • 1 2009

  • Refine by Author
  • 1 Eguchi, Ryota
  • 1 Hirose, Jion
  • 1 Inoue, Masashi
  • 1 Sudo, Yuichi

  • Refine by Series/Journal
  • 1 LIPIcs
  • 1 DagSemProc

  • Refine by Classification
  • 1 Theory of computation → Distributed algorithms

  • Refine by Keyword
  • 1 Byzantine environments
  • 1 Distributed algorithms
  • 1 Gathering
  • 1 Image retrieval
  • 1 insufficiency
  • Show More...

Any Issues?
X

Feedback on the Current Page

CAPTCHA

Thanks for your feedback!

Feedback submitted to Dagstuhl Publishing

Could not send message

Please try again later or send an E-mail