Based On The Semantic Extension In Chinese Information Retrieval System Design And Implementation

With the rapid development of the information technology and Internet, thenumber of document is growing in exponential. It is becoming a challenging task toobtain needed information from massive,dynamic and diverse knowledge database. Inmany information retrieval systems, the user’s needs are expressed by query words atpresent. The actual needs of users and query words often exist semantic gap. In this casethrough giving semantics to retrieval conditions, information organization and searchresults, we could compensate for the deficiency of existing information retrievaltechnology. In Chinese there exist a lot of synonyms, which are different in forms butsimilar in meaning. In information retrieval system, because the keywords cannot solvethis phenomenon, which leads to some of the documents cannot be retrieved accurately,and search properties are low. Query expansion is becoming an effective method tosolving this mismatch problem.Comprehensive analysis of traditional retrieval problems of extension method, putsforward a query expansion algorithm based on the concept of local co-occurrenceanalysis, through the concept of semantic space extended the original query, getextended concept, and the first retrieval; To adopt the method of support vector machine(SVM) classification retrieval results, according to theory of co-occurrence analysiscorresponding concept focuses on the degree of the query word co-occurrence betweendifferent concepts, according to the analysis of function values for sorting, get the finalset of extended concept. On the test set of the experimental results show that the methodgreatly improved the retrieval performance of the algorithm. Comprehensive analysis ofthe query expansion algorithm based on local co-occurrence information retrievalsystem structure performance, the algorithm steps and node structure.Adopting relevant technical analysis on the basis of semantic extension andmatching information retrieval system structure, the information retrieval system iseffective division of hierarchy and the function, the system operation process of thecorresponding analysis, improve the similarity computing model based on theco-occurrence degree, and put forward based on the co-occurrence degree of semanticsimilarity matching algorithm. And analyzed in detail based on Forward node of semantic similarity-Opposite node routing algorithm and data structure.Using computer programming language and the specific conditions, testing system,the results show that the algorithm proposed in this paper designed the running state ofthe information retrieval system is more stable, meeting its function, than the traditionalretrieval system has a better retrieval effect.