Author(s): Sahar Aljalbout, Gilles Falquet
Abstract: Annotating RDF data with contextual information such as provenance, space, temporal validity, etc. is becoming more and more crucial on the semantic web. However, defining an efficient representation and reasoning on such meta-knowledge remains challenging. This is due to the fact that the representation of statement annotations has sometimes been thought of as an RDF data problem without consideration of the logical formalism behind it. As a consequence, the underlying data structure lacks a clear formal semantics. In this paper, we study both levels: the logical formalism and the data model. First, we define a contextualized description logic. The formalism allows the representation of several contextual dimensions and considers contexts as first-class citizens, which offers an expressive formal language that supports the representation and reasoning of contextualized knowledge. Second, we present a contextual data model based on the N-ary pattern and we study the mapping of the contextual description logics constructors and axioms onto this model. Finally, we present a simple mechanism for reasoning with contextual statements. It involves the use of SWRL and SPARQL to implement inference rules that constitute a contextualized version of the OWL-2 profile rules and we show that this mechanism is technically straightforward to implement with the existing semantic web tools.
Keywords: Semantic Web; Contexts; Contextual Ontologies; Contextual reasoning; Contextual Description Logics; Contextual OWL