Ubiquitous Web Services for E-Government Social Services

The Semantic Web is defined as an extension of the existing Web, in which information is given a well-defined meaning (Berners-Lee, Hendler, & Lassila 2001). The ultimate goal of the envisioned Semantic Web is to transform the Web into a medium through which data and applications can be automatically understood and processed. The development of technologies for supporting the Semantic Web has been the priority of various research communities (e.g., database, artificial intelligence). A major component in enabling the Semantic Web is the concept of Web services (Alonso et al. 2003; McIlraith, Son, & Zeng 2001; Medjahed et al. 2003). A Web service is a set of related functionalities that can be programmatically accessed through the Web. Examples of Web services span several application domains including e-government (e.g., welfare social service) and B2B E-commerce (e.g., stock trading). Web services are gradually taking root because of the convergence of business and government efforts to making the Web the place of choice for all types of activities. The maturity of XML-based Web service technologies such as SOAP, UDDI, and WSDL is a prominent factor contributing to the large adoption of Web services in the near future (Curbera et al. 2002). Web services have spurred an intense activity in industry and academia to address challenging research issues such as the automatic composition, optimized querying, and customized presentation of Web services. Service composition includes the automatic selection and interoperation of individual Web services to provide value-added and personalized composite services. Optimized service query offers complex and optimized query facilities for combining accesses to diverse service providers. The customized service presentation presents interfaces based on the service input/output data and service semantics. The diversity of these issues calls for the design and development of a comprehensive Web Service Management System (WSMS), where Web services would be treated as first-class objects that can be manipulated as if they were pieces of data. A WSMS includes the architectural components that introduce more convenience, flexibility, and effectiveness in managing Web