Learn More
Due to the growing popularity of Description Logics-based knowledge representation systems, predominantly in the context of Semantic Web applications, there is a rising demand for tools offering non-standard reasoning services. One particularly interesting form of reasoning, both from the user as well as the ontology engineering perspective, is abduction.(More)
Establishing a generic approach to representing and querying temporal data in the context of Description Logics (DLs) is an important, and still open challenge. The difficulty lies in that a proposed approach should reconcile a number of valuable contributions coming from diverse, yet relevant research lines, such as temporal databases and query answering(More)
Description Logics (DLs) provide a clear and broadly accepted paradigm for modeling and reasoning about terminological knowledge. However, it has been often noted, that although DLs are well-suited for representing a single, global viewpoint on an application domain, they offer no formal grounding for dealing with knowledge pertaining to multiple(More)
We introduce an extension of Description Logics (DLs) for representing and reasoning about contextualized knowledge. Our formalism is inspired by McCarthy's theory of formalizing contexts and based on two-dimensional semantics, with one dimension representing a usual object domain and the other a domain of contexts. Additionally, it is equipped with a(More)
In many domains concept definitions undergo change on a relatively frequent basis. Especially in law, such changes can have far reaching consequences. Existing ontology versioning techniques often do not consider that old and new definitions may need to co-exist side by side in a knowledge base, or they require non-standard language extensions. In this(More)
The formal definition of abduction asks what needs to be added to a knowledge base to enable an observation to be entailed. TBox abduction in description logics (DLs) asks what TBox axioms need to be added to a DL knowledge base to allow a TBox axiom to be entailed. We describe a sound and complete algorithm, based on the standard DL tableau, that takes a(More)