Proper query terms significantly affect the performance of information retrieval systems. In this paper, a conceptual weighting method for query expansion is proposed with the help of user profile. Here, the users' initial queries and the retrieved documents based on the user's query (top n relevant documents) are analyzed and then the relevant terms from the documents retrieved are weighted. The terms having higher weight and the terms from the previous searches with a greater threshold weight will be selected and are used to derive the concepts in the concept network which are then connected to the phrases. Based on the matching of those phrases with that of the query phrases, additional query terms are selected and based on those additional query terms, the user's original query is expanded and the search is enhanced.

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Natural Language Processing Query Expansion Term-weighting Concept Networks User Profiles Information Retrieval