Application Of Ontology Theory In Web Services

Ontology originated in philosophy. Since 1990's, some workshops on ontology have been held in the international computer community.Ontoloty has become one of the main technologies of knowledge representation, knowledge management, knowledge sharing and knowledge reuse by now. It is also becoming a common pivotal subject among the research fields such as NLP, web information retrieval, database management, knowledge management, heterogeneous data integration, digital libraries, GIS, semantic Web, etc.Today Web Services have become a common means of e-commerce. However, with the development of Web Services applications, Web Services face with the high cost of development, composition error-prone, high maintenance costs, low efficiency, low timeliness such issues. At the same time Web application is also facing with automation and semantic issues such as maintaining. Semantic Web Services are the combination of Web Services and Semantic Web, which is the best solution to the above problem. Ontological theory research, including Semantic Web research and Web Services research, in multi-storey framework of Semantic Web, Ontology layer locates between documents described layer and knowledge reasoning layer, so ontology research, description, construction are the key to achieve Semantic Web and Web Services.Under the guidance of these theories, the main research works in this dissertation:(1)Traditional workflow model is often a static model, is difficult to adapt to the modern enterprise business processes need, which is the motivation of the dynamic model proposed. This dissertation proposes a semi-structured based the work flow Ontology, and establishes a dynamic flow model BAWS_WFMS on the basis of this, elaborates architecture of BAWS_WFMS and functions of component, analyzes several cases during semantic matching process, as well as the composition rules.(2) Based on the architecture of BAWS_WFMS, Web Services discovery is a very critical connection during Web Services deployment,discovery,composition process. This dissertation proposes a DDC algorithm, considering syntax similarity,operation similarity,semanteme similarity during the Web Services discovery process, as well as the high efficiency,low cost, and analyzes its performance and characteristics.(3) DDC algorithm proposed solves mainly two areas inadequate of the existed algorithm:①through semantic mapping, avoids blind matching, increases efficiency to the success of the match②through semantic mapping, identifies the target service is a single service or non-trivial services, and enhances the efficiency of discovery of a target service. Through examples we demonstrate that the feasibility of the algorithm, accuracy and effectiveness.