Extending OWL by fuzzy description logic

Technology about ontology plays an important role in all kinds of technologies about the semantic Web. OWL, the standard Web ontology language is proposed by W3C. Vocabularies in OWL only represent certain and complete concepts and roles. In order to represent fuzzy knowledge, this paper extends existing OWL language by encoding fuzzy constructors, axioms and constraints and maps semantics of these new vocabularies to fuzzy description logic. Extended OWL can represent fuzzy ontology and resolve some fuzzy entailment tasks by constraint propagation calculus of fuzzy description logic.