Filling the Gap between OWL 2 QL and QuOnto: ROWLKit

Ontologies are nowadays one of the most prominent formalisms used in the area of Semantic Web for knowledge representation. Several efforts have been made by the W3C in order to define OWL (Web Ontology Language) and by developers in order to develop reasoners able to deal with ontologies defined by means of OWL. Unfortunately, the goals of the working groups for standard languages definition rarely meet the ones of reasoners developers and viceversa. In this paper we present ROWLKit, a query answering system for ontologies compliant with OWL 2 QL, a profile of OWL 2 that is inspired by DL-LiteR, one of the language of the DL-Lite family. In particular we show how to extend QuOnto, a pre-existing reasoner for DL-LiteR in order to implement the features of OWL 2 QL not natively supported by QuOnto thus bridging the gap between the standard language and the system implementation. We show the efficacy of our approach presenting experimental results based on the University Ontology Benchmark.