Expansion Model of Semantic Query Based on Ontology

An expansion model of semantic query based on ontology is proposed for the problem of ldquoexpression differencerdquo and ldquomechanical matchrdquo that usually exists in information retrieval. By using domain knowledge in ontology, retrieval system can improve semantic understanding of retrieval documents, and give the chance to user to put their information request in more nature way (more precise way), which will surely optimize the whole searching process and raise the relativity of query words and documents, further improve the recall and precision ratios of information retrieval. To perform the semantic expansion based on ontology, semantic expansion algorithm and semantic expansion functions based on ontology are proposed and used in the model. As is indicated by the experiment, this model is suitable for promoting online information retrieval and the accuracy of searching is highly improved.