Abstract: Compared with traditional search,mobile search is sensitive to the users’ environment information such as location,temperature,speed and so on．In order to use the environment information to infer the user intents,an expansion approach based on environment information was proposed,which has been applied in the Clever Search Engine(CSE)——a mobile search system we developed．Using segmented queries and users’ environment information,the approach infers the user intents through the expert system and expands query in order to realize personalized query expansion．Experimental results show that the approach we proposed can significantly improve users’ search experiences and has better performance in precision than existing public search engine(e.g．Google).

Key words: Query expansion,Mobile search,Expert system,Personalization,Algorithm