Research, Service-based Meta-search Engine

With the rapid development of the Internet, the Web, which is an enormous knowledge base, was relied on by people more and more. Search engines, known as the interface to users who use network information, have been in development since it emerged. Meanwhile, with the popularization of computer and the increasing need of people' s reading on computers, the digital library and the relevant technologies spring up and have been growing. Obtaining query from documents and submitting the query to the search engines has been the one of the common patterns of the modern information searching and knowledge obtaining. However, the coverage of the search engine is not ideal, while the meta-search engine can solve this problem. As a result, the meta-search engine has been the data sources of information system. And we adopt the Meta-search Engine as the information source component of the General Objects Evaluates System.In the system, the meta-search engine is based on Web Service and Middleware of Messages (MOM), whose brokers of component search engines is divided and independent. As a result, the coupling between them is loose, and the internal models could be loaded and unloaded easily. From the outer system, the Web Service interface could be invoked without the understanding of the system. And the dynamically invoking many domain knowledge bases is adopted to satisfy the retrieval demand in many domain.Basing on study on the query parameters sets of component search engines, the evaluate model on the query interfaces expression capacity of component search engines was given. At last, the experiments based on the model were carried out to find out the best query parameters set of the meta-search engine which could get precise enough result and lower the complication in the translation of the query.