Different aspects of query rewriting for fuzzy OWL2EL

The use of ontologies in the Semantic Web allows for semantic query answering. The problem of answering queries in term of ontologies defined using Description Logic formalisms suffers from high worst-case complexity. The problem becomes more complex with fuzzy ontologies as fuzzy DLs should allow human-like expression and approximate reasoning. Many approaches for query rewriting have been proposed for enhancing crisp query processing. Given a query Q, the most common approach to query rewriting is the use of the terminological level of the knowledge base in order to define a query Q′ that can be correctly evaluated on the assertional level only. Query rewriting for fuzzy knowledge base is not well treated in the literature. In this paper, we discuss different aspects of query rewriting for fuzzy OWL2EL ontologies and we propose to use rule based reasoning and views to enhance this process.