Abstract: The method of Web service composition proposed by open gcospatial consortium(OGC) can compose various Web services to form a sort of workflow(OGC Web Services 2 , OWS2) , but it is a static workflow with exact matching. The DWFMOR(Dynamic Work Flow Model based on Ontology and Rule) put forward by this paper can form a dynes mic workflow based on geo-ontology with the specified rules. This model was extended from OWS2. Firstly the domain spatial ontology-geo-ontology was created with the special spatial feature. Secondly the engine of workflow was designed for inference based on gco-ontology. Then this engine was implemented by using Stanford protcgc and HP Jena reasoner. At last , a DWFMOR prototype was developed on the Java platform. The experiment shows that DWFMOR can search-match Web ser-vices automatically and dynamically form a kind of workflow for spatial information Web services according to the business requirement.

Key words: Work flow, Ontology, Rule engine, OGC Web service