Research Of Approach To Geographic Information Search Based On Ontology

The development of GIS is being in gradual progress from desktop-GIS, stand-alone GIS system to popular and distributed great capacity GIS based on network. In order to realize geographic information share, researchers from different disciplines have made much valuable attempt using different methods. Ontology describes semantic, expresses common understanding knowledge by defining concepts and relation among concepts and provides basic theory and methodological guidance for information share.The main research contents of the paper are as follows:The first, the paper explains the basic meaning of ontology, introduces in detail the application of ontology in geographic information system; the second, this paper emphatically discusses the characteristics of geographic ontology, points out that levels of concepts are powerful tools to describe and organize knowledge, spatial feature is essential one of geographic ontology and the social properties of geographic entity are focus people cared. The fourth, discusses different methods to build geographic domain ontology based on afore-mentioned research.The paper discusses many methods that improve query efficiency, including optimized query, expanded query and presentation of query results based geographic ontology, designs and realizes an urban geographic information query prototype. This prototype system benefits from recalled way in traditional information system to query spatial information (that is, input vocabularies or sentences), satisfies people's query custom and reduces difficulty that users query spatial information. At the same time, the paper researches the problems how to use ontology to optimize and expand query, realizes intelligent spatial information query knowledgeable and semantic levels.