The Fuzzy Ontology Reasoner fuzzyDL

Classical, two-valued, ontologies have been successfully applied to represent the knowledge in many domains. However, it has been pointed out that they are not suitable in domains where vague or imprecise pieces of information play an important role. To overcome this limitation, several extensions to classical ontologies based on fuzzy logic have been proposed. We believe, however, that the success of fuzzy ontologies strongly depends on the availability of effective reasoners able to deal with fuzzy ontologies. In this paper we describe fuzzyDL, an expressive fuzzy ontology reasoner with some unique features. We discuss its possibilities for fuzzy ontology representation, the supported reasoning services, the different interfaces to interact with it, some implementation details, a comparison with other fuzzy ontology reasoners, and an overview of the main applications that have used it so far.