Fuzzy ontologies: The state of the art

Ontologies play a central role in the Semantic Web. Much research has focused on extending ontologies and Semantic Web technologies to handle uncertain information. This paper provides a review of recent approaches for extending ontologies to fuzzy ontologies. Some approaches have been developed for application specific purposes, for example for information retrieval and search on the Semantic Web and are not formally relying on current Semantic Web technologies such as standard web ontology languages and tools such as ontology editors or reasoners. Other approaches emphasize developing methods to extend Semantic Web standard technologies with fuzzy logic and fuzzy reasoning.