Two essential tasks in managing description logic knowledge bases are eliminating problematic axioms and incorporating newly formed ones. Such elimination and incorporation are formalised as the operations of contraction and revision in belief change. In this paper, we deal with contraction and revision for the DL-Lite family through a model-theoretic approach. Standard description logic semant...

We analyse DL-Lite logics with role inclusions and present a complete classification of the trade-off between their expressiveness and computational complexity. In particular, we show that in logics with role inclusions the data complexity of instance checking becomes P-hard in the presence of functionality constraints, and coNP-hard if arbitrary number restrictions are allowed, even with a ver...

Reasoning capability is of crucial importance to many applications developed for the Semantic Web. Description Logics provide sound and complete reasoning algorithms that can effectively handle the DL fragment of the Web Ontology Language (OWL). However, existing DL reasoners were implemented long before OWL came into existence and lack some features that are essential for Semantic Web applicat...

In several application domains, the need arises of modeling and reasoning about meta-concepts and meta-properties. This is the case, for example, with information system interoperability, where a description of the data schema (or, the ontology) of one system should co-exist with the specification of the application domain described by the data schema itself. In logic, higher-order constructs a...

We introduce a mechanism called lifting to share predicates between the two components of a dl-program, integrating them in a tighter way. Using lifting, one can reason about the predicates being shared both via the description logic knowledge base and via Datalogstyle rules, and the deductions one makes are automatically reflected globally on both components. This is a capability not directly ...