DLRule: A Rule Editor plug-in for Protege

OWL is a very expressive language, but some user obviously struggle to formulate what they want to say. Now, some of these users may find it easier to write down a SWRL rule instead of an OWL axiom. Hence, we present a rule editor plug-in for Protégé that brings something different to rule and OWL integration. We part from the two usual approaches: (i) use it as is with say, Hoolet, knowing that it leads to undecidability. (ii) Or make it DL-safe, but then it restricts the semantic impact and, e.g., looses the nice “car owners are engine owners” inference. This plug-in implements a rewriting technique that rewrites certain forms of rules into DL axioms using OWL 1.1’s new features. These rules rewritten as OWL 1.1 axioms do not require DL-safety, thus allow the extra inferences, and do not cause any undecidability. In this paper, we outline the rewriting technique, present the plug-in and give some practical results.