Holger Lausen

Semantic web portals: state‐of‐the‐art survey

Purpose – To present the state of the arts application of semantic web technologies in web portals and corresponding achievable improvements for identifying the potential improvement made by semantic web technology.Design/methodology/approach – An evaluation scheme is proposed to investigate various web portals that make use of semantic web technologies in order to identify their strengths and weaknesses. This scheme consists of three layers: information access, information processing and grounding technologies. Two academic portals and two commercial portals are selected based on the definition of semantic web portal. Detailed evaluation based on the proposed scheme is conducted on these four select portals.Findings – Semantic web technologies can definitely increase the information consistency and the information processing quality of web portals by using ontologies to model portal structure and consensus knowledge. Furthermore, semantic web services will be acting as the key technologies to lift curren...

Evaluation of Semantic Service Discovery—A Survey and Directions for Future Research

In recent years a huge amount of effort, and money has been invested in the area of semantic service discovery and presented approaches have become more sophisticated and mature. Nevertheless surprisingly little effort is being put into the evaluation of these approaches. We argue that the lack of established and theoretically well-founded methodologies and test beds for comparative evaluation of semantic service discovery is a major blocker of the advancement of the field. To lay the ground for a comprehensive treatment of this problem we discuss the applicability of well-known evaluation methodologies from information retrieval and provide an exhaustive survey of the current evaluation approaches.

Active Ontologies for Data Source Queries

In this paper we describe the work that was done in the Corporate Ontology Grid (COG) project on the querying of existing legacy data sources from the automotive industry using ontology technology and a conceptual ontology query language. We describe the conceptual ontology query language developed by Unicorn, the querying support provided by the Unicorn Workbench, and describe the use of these queries in the run-time architecture built in the COG project.