Research On Province Information Website's Vertical Search Engine Based On Ontology

With the deep building of the e-government and fast increasing of the government's portal websites, the quantity of their carrying information resources becomes larger and larger, but the portal websites also can not get rid of the fate of being isolated islands of information and the building models for the traditional government portal websites are confronted with some crisis and some challenge. So the model building portal websites with search engine emerges.Perhaps general search engines can have good performance in getting the portal websites' information in the "quantity", but it does not do so well in getting the information in the "quality", which in other words is to let users easily find the things that they are really interested in. While the vertical search engine provides some valuable information and some related services for a particular field, a specific group of people or a specific demand. And the ontology precisely is the abstract and description of the concept of the domain, so the ontology is naturally combined with the search engine technologies as a good weapon to study the vertical search engine.Then how to build the application ontology and how to specifically combine several key technologies on the ontology with the search engine become the difficult points of the study.In the beginning, this thesis talks about the basic concepts of the search engine and its development status, evaluation indicators and development trends. And it expounds the significance and necessity of combining the ontology with the vertical search engine, and then it introduces some theories about the ontology, some knowledge about the natural language processing and the development of Java Toolbox Jena, which is based on the OWL RDF and semantic (semantic) Web Application procedures. Finally, the ontology of the Hubei Province Information Website is developed, and there are the search engine system structure of the Hubei Province Information Website based on the ontology and its specific methods. And in it, it focuses on the following two issues:1. To study and construct the ontology of the Hubei Province Information Website; to put forward the idea by using the method called IDEF-5 to construct the ontology of the Hubei Province Information Website, which is combined with the software engineering; to develop part of the ontology of the Hubei Province Information Website, with the protege3.2 as the editorial tool and the OWL as the development language of the ontology.2. To study and put forwards the vertical search engine system structure of the Hubei Province Information Website based on the ontology; to give the specific algorithms of the key technologies such as the ontology-based information collection, the ontology-based information extraction and the ontology-based retrieval.