F-Logic#: Loosely Coupling F-Logic Rules and Ontologies

Abstract

In W3C's Rule Interchange Format (RIF), FLogic rules have received considerable attention as a major logical rule formalism, while combinations of rules with Description Logic (DL) ontologies in RIF, let alone with FLogic rules, are far less developed. To mend this, we first present F-Logic# knowledge bases, a framework based on the semantics of the well-investigated dl-programs, that provides a loose coupling approach to integrating F-Logic rules and DL ontologies by allowing rules to query the ontology using external atoms. We investigate the semantical properties of this framework and define a stratified fragment that allows for fast reasoning -a necessity on a Web with large amounts of data. We then shape F-Logic# as a RIF dialect, setting it firmly in a Web context and providing an expressive combination of F-Logic rules with DL ontologies in RIF. Finally, we show how to extend the F-Logic rule engine OntoBroker towards reasoning with F-Logic#, enabling as such a first commercial implementation for loosely-coupled ontologies and rules.

Semantic Independence in DL-Programs

“…[4,9,13,19,17,3], and the concept of DL-atom has been adopted and generalized by other formalisms e.g. [18,10,6].…”

Uniform Evaluation of Nonmonotonic DL-Programs

“…This approach is fostered by nonmonotonic description logic (dl-) programs [17], where this exchange is handled by a generalization of the answer set semantics of nonmonotonic logic programs [23]. Follow up work has adapted this approach to other formalisms (e.g., [51,29,20]) and considered alternative semantics (e.g. [39,52,16]).…”