The User's Knowledge Model Is Automatically Created With The Evolution Of Technology

For precision of search engine, personalized information retrieval has been the focus question of research to search out one's most interested contents precisely and efficiently.This paper focuses on core of personalized search engine - user model. Firstly, the paper sum up developing history, status, tendency of knowledge management, search engine, user model and relevant feedback, then introduces the main issues of information retrieval, user model, relevant feedback theories and technology, points out the main questions of existing state at last.After analyzing user interest model and domain knowledge model, user knowledge model is brought forward in this paper, which thinks over the information contained in the user knowledge, the user interest model. It is sepreated user knowledge model as knowledge organization from personalized information retrieval as knowledge application, and the user relevant feedback is regarded as one of methods in knowledge acquisition. The model contains more information than the resource information of traditional information retrieval model and the user interest information of traditional information model, and moreover, the rough concept lattice based personalized information retrieval model can identify the new knowledge and interest of users and find the documents of new interest. In this paper we discussed theory include concept, properties and algorithm of user knowledge model, presented by rough concept lattice, modeling and evolving automatically.A personalized information retrieval system named School Search Engine based on J2EE is designed and implemented in this paper, overall function module, structure analysis and system implementation. School Search Engine has been used in NanHua University website, and holds well reputation.