On Reformulation of Constraint Satisfaction Problems
نویسندگان
چکیده
The performance of constraint based problem solving depends crucially on the problem representation. The same problem may be easy or diicult to solve depending on the way we formulate it. In this paper, we study reformu-lations of discrete constraint satisfaction problems (CSPs). We present a technique to transform a CSP P into its Boolean form, which allows us to nd diierent reformulations of P. We identify a new class of tractable CSPs and present suucient conditions for detecting solvability and unsolvability of a CSP in linear time. Finally we introduce the notion of fault tolerance of solutions, and show how the Boolean form can be used to nd them.
منابع مشابه
Interchangeability Supports Abstraction and Reformulation for Multi-Dimensional Constraint Satisfaction
Interchangeability provides a principled approach to abstraction and reformulation of constraint satisfaction problems. Values are interchangeable if exchanging one for the other in any solution produces another solution. Abstracting a problem by simplifying the constraints can increase interchangeability. Multi-dimensional constraint satisfaction problems can provide natural opportunities for ...
متن کاملfor Multi - Dimensional Constraint Satisfaction
Interchangeability provides a principled approach to abstraction and reformulation of constraint satisfaction problems. Values are interchangeable if exchanging one for the other in any solution produces another solution. Abstracting a problem by simplifying the constraints can increase interchangeability. Multi-dimensional constraint satisfaction problems can provide natural opportunities for ...
متن کاملAutomatable High-Level Integration of Constraint Programs
We propose a reformulation algorithm as well as a set of re-formulation rules for models of constraint satisfaction problems written in our high-level constraint programming language esra, which is more expressive than opl and is compiled into opl. For the class of mapping problems, the reformulation algorithm achieves models that integrate a constraint programming formulation and an integer pr...
متن کاملGreater Efficiency for Conditional Constraint Satisfaction
A conditional constraint satisfaction problem (CCSP) extends a standard constraint satisfaction problem (CPS) with a conditionbased component that controls what variables participate in problem solutions. CCSPs adequately represent configuration and design problems in which selected subsets of variables, rather than the entire variable set, are relevant to final solutions. The only algorithm th...
متن کاملReformulating Constraint Models for Classical Planning
Constraint satisfaction techniques are commonly used for solving scheduling problems, still they are rare in AI planning. Although there are several attempts to apply constraint satisfaction for solving AI planning problems, these techniques never became predominant in planning; and they never reached the success of, for example, SATbased planners. In this paper we argue that existing constrain...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 1998