Research Of Collection Of Web Information Based On Domain Ontology

With the popularity of the Internet and the rapid growth of web information.Brousing information online has become part of human being's life.Different users have different individual needs. However, the need of the real-life information of the users is varied, the contents provided by the Web Search Engine search can not satisfy all the user's needs. so people need to put the results of Web Search Engines to format in order to meet the users' requirements. In fact, the ontology as describing the concept of modeling tools in semantic and knowledge levels, which has a good hierarchy and the ability of logical reasoning. Therefore, information retrieval. ontology technology has been applied widely. especially in the field of knowledge-based semantic retrieval.This thesis aims at ontology technologies into the medical domain ontology of information acquisition. In this way, it improves the quality of search engines, this approach has changed the traditional reliance on keyword search at the time of the recall and precision is not high. After analysis of the existing retrieval methods, this paper built medical domain ontology based on the relevant domain ontology technology and presented a new model based on domain ontology search. At the same time. This paper analysised and researched on retrieval models semantic extensions. semantic similarity algorithms. search engine specific implementation and other aspects. The main research work as follow:Firstly, ontology construction methods have been improved. Ontology related concepts have been exended according to ontology hierarchy relationship. So retrieval system of reasoning capabilities has been improved.Secondly, through domain ontology concepts, construction methods and construction principle's study, using ontology building tool Protege2000, a domain ontology based on medical care has been built.Thirdly, proposed a new domain ontology search model; put forward a based on full study of concept semantic similarity algorithm; improved semantic similarity algorithm and built a generic search engine by changing some parameters.