Special Issue on Semantic Web: Opportunities and Challenges

The Web is constantly changing the way we live and the way businesses operate. While the Web is successfully growing into a massively distributed reservoir of information, the information often lacks an explicit, well-defined, machine-understandable meaning attached to it, prohibiting automated manipulation and reasoning about it. The emerging semantic Web paradigm promises to remedy this deficiency and thereby enable the full potential of the Web. The ambitious vision of this paradigm has excited researchers in various areas, including semantic modeling, distributed and heterogeneous information systems, and artificial intelligence. New technologies, such as ontologies and semantic Web services, are being proposed, developed, and standardized. Existing methodologies and techniques are being adapted and applied in this new paradigm. New application opportunities are being discovered and pursued. The purpose of this special issue is to provide a focused outlet for recent advances in realizing the semantic Web vision, including new research results and developments as well as applications of existing research results in this emerging fascinating area. Our goal is to identify the current state of the art in available and emerging methodologies, tools, technologies, standards, and applications, and to envisage future opportunities and challenges of the research in this area. In this special issue, we present three selected articles that address some of these aspects. The first article, entitled ‘‘Extracting Knowledge from XML Document Repository: A Semantic WebBased Approach’’ by Henry M. Kim and Arijit Sengupta, describes a method to automatically extract knowledge from a document corpus of some domain. It presents an ontology based methodology and tool framework, called KROX (Knowledge Retrieval using Ontologies and XML). The ontology engineering methodology used in KROX comprises several steps, including motivating scenario specification, competency questions formulation, ontology development, and ontology evaluation. The resulting ontology is formally defined by a terminology and an associated set of axioms. The ontology then enables automatic inference of additional knowledge not explicitly represented in the document repository. The second article, entitled ‘‘Enterprise Application Reuse: Semantic Discovery of Business Grid Services’’ by David Bell, Simone A. Ludwig, and Mark Lycett, investigates an extension of the Web services paradigm by ‘‘business grid services’’. It presents a capability based service discovery architecture, called SEDI4G (Semantic Discovery for Grid Services), for discovering reusable grid-enabled enterprise software components. SEDI4G extracts the semantics of software components from their syntactic capability descriptions and operational characteristics and uses a semantic matching method to match the capabilities of potentially suitable components against user queries. This work demonstrates the potential benefits of the fusion of the Web services paradigm and the grid paradigm. S. Ram Department of Management Information Systems, Eller College of Management, University of Arizona, 1130 E. Helen Street, Tucson, AZ 85721-0108, USA e-mail: ram@eller.arizona.edu