Generally the query input by a user contains terms that do not match those terms which are used to index the majority of the relevant documents. Sometimes the un-retrieved relevant documents are indexed by a different set of terms than those in the query. In order to solve this problem it is necessary to modify the user's query. To do so the researchers have proposed query expansion to help the user to formulate what information is actually needed. For nonnumeric terms researchers purposed many good solutions but as numerical values do not have any synonyms or stemming words, previous approaches were restricted to match the document exactly to the numerical terms that were present in the query. The method presented in this paper searches for the approximate matching of numerical terms also. The method uses fuzzy weighing of query terms with the help of fuzzy triangular membership function.

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Fuzzy Membership Function Numerical Terms Query Expansion Term-weighting Information Retrieval