We introduce tree-width for first order formulae φ, fotw(φ). We show that computing fotw is fixed-parameter tractable with parameter fotw. Moreover, we show that on classes of formulae of bounded fotw, model checking is fixed parameter tractable, with parameter the length of the formula. This is done by translating a formula φ with fotw(φ) < k into a formula of the k-variable fragment L of firs...

The computational tasks of model-based diagnosis and planning in embedded systems can be framed as soft-constraint optimization problems with planning costs or state transition probabilities as preferences. Running constraint optimization in embedded systems requires to reduce complexity, which can be achieved by combining dynamic programming message-passing algorithms with message approximatio...

An optimal solution for a large number of constraint satisfaction problems can be found using the technique of substitution and elimination of variables analogous to the technique that is used to solve systems of equations. A decision function f(A)=max(A) is used to determine which variables to eliminate. The algorithm can be expressed in six lines and is remarkable in both its simplicity and i...

The considerable expressive power and exibility gained by combining constraint programming with logic programming is not without cost. Implementations of constraint logic programming (CLP) languages must include expensive constraint solving algorithms tailored to speciic domains, such as trees, Booleans, or real numbers. The performance of many current CLP compilers and interpreters does not en...

Linear constraint solving in constraint logic programming requires in cremental checks of the satis ability of a system of equations and inequali ties Experience has shown that Gauss Jordan elimination and the simplex method are e cient enough to be of practical value in the implementation of CLP languages based on linear arithmetic constraints However these algorithms must be modi ed to accomm...

Aim at the potential that the time efficiency of the technology of Cycle elimination for invocation graph-based context-sensitive pointer analysis can be improved. Through using wave and deep propagation method, which is the state-of-the-art techniques of Inclusion Based Pointer Analysis on-line optimization Technology, to optimize the technology of cycle elimination for invocation graph-based ...

In this paper we give a new algorithm for quanti-er elimination in the rst order theory of real closed elds that improves the complexity of the best known algorithm for this problem till now. Unlike previously known algorithms 3, 25, 20] the combinatorial part of the complexity of this new algorithm is independent of the number of free variables. Moreover, under the assumption that each polynom...