Research On The Composition Method Of GIS Web Services

The appearance of Web Services brings fresh energy to the development of WebGIS. The construction of GIS Web Services can integrate distributed ,heterogeneous GIS data and GIS functions, and resolve the problems which can't be resolved in traditional WebGIS.However, in the practical application, single GIS Web Service can not always be satisfied with the necessity of users. It is necessary to compose them to offer stronger efficacy. Now such work is often achieved by users although it is fussy and troubled. Therefore, it is quite meaningful to study how to compose existing Web Services dynamically according to service request.This paper contains as follows:1. On the basis of researching the principle and architecture of Web Services, this paper brings forward GIS Web Services framework based on .NET platform, discusses how to construct GIS Web Services and it's applications.2. This paper researches how to describe the semantic meaning of GIS Web Services, sets up geographic information domain ontology, describes the conception of geographic information domain and relationship of conceptions exactly. Under the restriction of geographic information domain ontology, it formalizes GIS Services according OWL-S, establishes foundations for Web services discovery and composition.3. This paper discusses the method of Web Services Composition. On the basis of domain ontology and OWL-S, it discusses the matching rules of Web Services, realizes the best arithmetic of Web Services Composition. At last, it brings forward geographic information automatic Web Services framework based on OWL-S and agent, and introduces the function of modules briefly.