A Graph Based Synthesis Algorithm for Solving CSPs

Many AI tasks can be formalized as constraint satisfaction problems (CSPs), which involve finding values for variables subject to a set of constraints. While solving a CSP is an NP-complete task in general, it is believed that efficiency can be significantly improved by exploiting the characteristics of the problem. In this paper, we present a solution synthesis algorithm called ω-CDGT which is an existing algorithm named CDGT augmented with a constraint representative graph called ω-graph. We show that the worst-case complexity of the ω-CDGT algorithm is better than other related algorithms.

[1]  Wanlin Pang,et al.  Characterizing Tractable CSPs , 1998, Canadian Conference on AI.

[2]  Philippe Jégou,et al.  On the Consistency of General Constraint-Satisfaction Problems , 1993, AAAI.

[3]  Shimon Even,et al.  Graph Algorithms , 1979 .

[4]  Rina Dechter,et al.  Tree Clustering for Constraint Networks , 1989, Artif. Intell..

[5]  Alan K. Mackworth.  Consistency in Networks of Relations , 1977, Artif. Intell..

[6]  Raimund Seidel,et al.  A New Method for Solving Constraint Satisfaction Problems , 1981, IJCAI.

[7]  Marc Gyssens,et al.  Decomposing Constraint Satisfaction Problems Using Database Techniques , 1994, Artif. Intell..

[8]  Rina Dechter,et al.  Network-based heuristics for constraint satisfaction problems , 1988 .

[9]  Eugene C. Freuder.  Synthesizing constraint expressions , 1978, CACM.

[10]  J. J. McGregor.  Relational consistency algorithms and their application in finding subgraph and graph isomorphisms , 1979, Inf. Sci..

[11]  Eugene C. Freuder.  Backtrack-free and backtrack-bounded search , 1988 .

[12]  W. D. Goodwin.  A Revised Sufficient Condition for Backtrack-Free Search , 1997 .

[13]  Yangjun Chen,et al.  Improving Han and Lee's path consistency algorithm , 1991, [Proceedings] Third International Conference on Tools for Artificial Intelligence - TAI 91.

[14]  Wanlin Pang,et al.  Constraint structure in constraint satisfaction problems , 1998 .

[15]  Pang,et al.  A new synthesis algorithm for solving CSPsWanlin , 1996 .

[16]  Wanlin Pang,et al.  Consistency in General CSPs , 2000, PRICAI.

[17]  Edward P. K. Tsang,et al.  Foundations of constraint satisfaction , 1993, Computation in cognitive science.

[18]  Thomas C. Henderson,et al.  Arc and Path Consistency Revisited , 1986, Artif. Intell..

[19]  Robert M. Haralick,et al.  Increasing Tree Search Efficiency for Constraint Satisfaction Problems , 1979, Artif. Intell..

[20]  Chia-Hoang Lee,et al.  Comments on Mohr and Henderson's Path Consistency Algorithm , 1988, Artif. Intell..

[21]  Philippe Jégou,et al.  On some partial line graphs of a hypergraph and the associated matroid , 1993, Discret. Math..

[22]  Christophe Lecoutre.  Constraint Networks , 1992 .