Reducing the Search Space of Resource Constrained DCOPs

  • Toshihiro Matsui
  • Marius Silaghi
  • Katsutoshi Hirayama
  • Makoto Yokoo
  • Boi Faltings
  • Hiroshi Matsuo
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6876)


Distributed constraint optimization problems (DCOPs) have been studied as a basic framework of multi-agent cooperation. The Resource Constrained DCOP (RCDCOP) is a special DCOP framework that contains n-ary hard constraints for shared resources. In RCDCOPs, for a value of a variable, a certain amount of the resource is consumed. Upper limits on the total use of resources are defined by n-ary resource constraints. To solve RCDCOPs, exact algorithms based on pseudo-trees employ virtual variables whose values represent use of the resources. Although, virtual variables allow for solving the problems without increasing the depth of the pseudo-tree, they exponentially increase the size of search spaces. Here, we reduce the search space of RCDCOPs solved by a dynamic programming method. Several boundaries of resource use are exploitable to reduce the size of the tables. To employ the boundaries, additional pre-processing and further filtering are applied. As a result, infeasible solutions are removed from the tables. Moreover, multiple elements of the tables are aggregated into fewer elements. By these modifications, redundancy of the search space is removed. One of our techniques reduces the size of the messages by an order of magnitude.


Search Space Resource Constraint Optimal Cost Infeasible Solution Optimal Assignment 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2011

Authors and Affiliations

  • Toshihiro Matsui
    • 1
  • Marius Silaghi
    • 2
  • Katsutoshi Hirayama
    • 3
  • Makoto Yokoo
    • 4
  • Boi Faltings
    • 5
  • Hiroshi Matsuo
    • 1
  1. 1.Nagoya Institute of TechnologyNagoyaJapan
  2. 2.Florida Institute of TechnologyMelbourneUnited States of America
  3. 3.Kobe UniversityKobeJapan
  4. 4.Kyushu UniversityFukuokaJapan
  5. 5.Swiss Federal Institute of Technology, Lausanne (EPFL)LausanneSwitzerland

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