一套結合語意網與Web 2.0技術的服務搜尋與組裝系統

Abstract

Web Services which are specific functionalities and can be combined to meet a particular user's needs have become a mature technology in the past few years. However, the discovery and search mechanism provided by UDDI based on keyword matching may lead to an ambiguous answer. It is a challenge to target the suiting Web services precisely. Semantic Web technology provides another option for service matching. It enables a service profile to be described according to its functionalities in OWL, which is based on Description Logics. Recently, researchers are dedicated on studying Semantic Web technology as a primary tool for ontology-based Web Services searching and invocation. With help of precise semantics description, Web Services are able to be utilized automatically. Under such a Semantic Web search mechanism, Web Services profile and domain ontology are both described by Description Logics. However, potential users often do not have any knowledge about Description Logics. That creates a huge gap and critically imposes high entrance barriers for the user. Besides, ontology maintenance is another important issue for Semantic Web applications. Ontology maintenance is a time-consuming job. Ontology maintenance is usually controlled by a small group of people. But it has several drawbacks: (1) the addition can be time-consuming and lack of completion and (2) the ontology maintainer read the concept in the different manner from how potential user does. Accordingly, sometimes concepts become obsolete by the time they enter the ontology. In the long run, ontology maintenance cannot be ignored especially in such a Semantic Web application. In this thesis, we proposed: (1) an open system architecture to lower the entrance barriers of Semantic Web applications, (2) a practical approach to ontology maintenance, and (3) a new prototype system. The Traveller was implemented based on our ontology- based architecture and related methodologies. With the service composition and execution architecture, the user is able to find suiting Web Services, invoke services by defining BPEL4WS, and participate in collaborative ontology maintenance without knowing any Semantic languages.