Research And Implementation Of The Semantic Retrieval Of Network Information Service Based On Query Expansion

The continuous growth of the network information brings a lot of convenience to the users, but at the same time, it also results in retrieval problems. Traditional keyword-based information retrieval techniques match the user's query only and result in missing the information expressed in different ways but with the same meaning. What's more, many of the query interfaces are only available to the fixed field of the website information retrieval services.For lacking of semantic information in the traditional keyword-based information retrieval techniques, we firstly study the semantic information retrieval techniques, and then propose RWIQE, a framework of semantic retrieval service for web information based on query expansion. RWIQE is more concerned about the semantic meaning of the user's query. RWIQE brings related expansion keywords to the user's query through query expansion. Thus can make the query closer to the true meaning of user's query and improve the efficiency of the query process. At the same time, a related diagram on hypernyms is generated automatically for the query keyword with the selected sense. What's more, in order to improve the efficiency of the information retrieval, a relational database based on user's history query is established.RWIQE is composed of three layers, data preparation layer, query expansion service layer and information retrieval layer. Firstly the web contents within the desired range should be fetched in the use of web crawler. Then create index to these contents and store the indexed documents in local depositary. After stripping out the query keywords of the user's, we do the dictionary-based query expansion process. Finally we can get the result pages using these expanded keywords.Using RWIQE service framework, we build a prototype system for a book renter site. The application results show that it performs well in query expansion, information retrieval precision rate and user experience, which verifies the validity of RWIQE framework.