Authors:
Amina Sambo-Magaji
;
Inés Arana
and
Hatem Ahriz
Affiliation:
Robert Gordon University, United Kingdom
Keyword(s):
Distributed Problems Solving, Local Search, Distributed Constraint Satisfaction, Heuristics.
Related
Ontology
Subjects/Areas/Topics:
Agents
;
Artificial Intelligence
;
Constraint Satisfaction
;
Distributed Problem Solving
;
Symbolic Systems
Abstract:
Distributed Constraint Satisfaction Problems (DisCSPs) solving techniques solve problems which are distributed over a number of agents.The distribution of the problem is required due to privacy, security or cost issues and, therefore centralised problem solving is inappropriate. Distributed local search is a framework that solves large combinatorial and optimization problems. For large problems it is often faster than distributed
systematic search methods. However, local search techniques are unable to detect unsolvability and have the propensity of getting stuck at local optima. Several strategies such as weights on constraints, penalties on values and probability have been used to escape local optima. In this paper, we present an approach for escaping local optima called Dynamic Agent Prioritisation and Penalties (DynAPP) which combines penalties on
variable values and dynamic variable prioritisation for the resolution of distributed constraint satisfaction problems. Empirical eval
uation with instances of random, meeting scheduling and graph colouring problems have shown that this approach solved more problems in less time at the phase transition when compared with some state of the art algorithms. Further evaluation of the DynAPP approach on iteration-bounded optimisation problems showed that DynAPP is competitive.
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