Learn More
We extend the framework of simple temporal problems studied originally by Dechter, Meiri and Pearl to consider constraints of the form x1 ?y1 r1 and n 1. We have implemented four progressively more eecient algorithms for the consistency checking problem for this class of temporal constraints. We have partially ordered those algorithms according to the(More)
A non-binary Constraint Satisfaction Problem (CSP) can be solved directly using extended versions of binary techniques. Alternatively, the non-binary problem can be translated into an equivalent binary one. In this case, it is generally accepted that the translated problem can be solved by applying well-established techniques for binary CSPs. In this paper(More)
The Stochastic CSP (SCSP) is a framework recently introduced by Walsh to capture combinatorial decision problems that involve uncertainty and probabilities. The SCSP extends the classical CSP by including both decision variables, that an agent can set, and stochastic variables that follow a probability distribution and can model uncertain events beyond the(More)
We make a number of contributions to the study of the Quantified Constraint Satisfaction Problem (QCSP). The QCSP is an extension of the constraint satisfaction problem that can be used to model combinatorial problems containing contingency or uncertainty. It allows for universally quantified variables that can model uncertain actions and events, such as(More)
Latest research efforts on the semi-automatic coordination of ontologies " touch " on the mapping /merging of ontologies using the whole breadth of available knowledge. Addressing this issue, this paper presents the HCONE-merge approach, which is further extended towards automating the merging process. HCONE-merge makes use of the intended informal meaning(More)
The Golomb ruler problem has been proposed as a challenging constraint satisfaction problem. We consider a large number of diierent models of this problem, both binary and non-binary. The problem can be modelled using quaternary constraints, but in practice using a set of auxiliary variables and ternary constraints gives better results. A binary encoding of(More)
In non-binary constraint satisfaction problems, the study of local consistencies that only prune values from domains has so far been largely limited to generalized arc consistency or weaker local consistency properties. This is in contrast with binary constraints where numerous such domain filtering consistencies have been proposed. In this paper we present(More)
We perform a comprehensive theoretical and empirical study of the benefits of singleton consistencies. Our theoretical results help place singleton consistencies within the hierarchy of local consistencies. To determine the practical value of these theoretical results, we measured the cost-effectiveness of pre-processing with singleton consistency(More)