Constraints over ontologies

Abstract

This paper presents a new constraint domain, where variables can be assigned values that are organised in a tree hierarchy. The introduction of this new constraint domain is motivated by applications for the configuration of product and services, for instance, in the context of e-commerce. The paper proposes a small constraint language, based on comparisons and the use of monotonic functions. An approximation of domains as convex sets is detailed and propagation rules for achieving bound-consistency on the constraints are reviewed. This new constraint domain is general, and the author hopes that it will be a useful tool not only for solving configuration problems but also for promoting constraint technology in new application domains related to content classification or the semantic web. © Springer-Verlag 2003.