Reasoning over Ontologies and Non-monotonic Rules

Ontology languages and non-monotonic rule languages are both well-known formalisms in knowledge representation and reasoning, each with its own distinct benefits and features which are quite orthogonal to each other. Both appear in the Semantic Web stack in distinct standards - OWL and RIF - and over the last decade a considerable research effort has been put into trying to provide a framework that combines the two. Yet, the considerable number of theoretical approaches resulted, so far, in very few practical reasoners, while realistic use-cases are scarce. In fact, there is little evidence that developing applications with combinations of ontologies and rules is actually viable. In this paper, we present a tool called NoHR that allows one to reason over ontologies and non-monotonic rules, illustrate its use in a realistic application, and provide tests of scalability of the tool, thereby showing that this research effort can be turned into practice.