Context mediation among knowledge discovery components

Acknowledgements I would like to express my gratitude to my supervisors Prof. John Hughes and Prof. David Bell for their guidance. The thesis has benefited from a number of research projects and the input provided by a range of individuals. Initial work was conducted at the University of Abertay, Scotland under the heartening guidance of Dr. Colin Miller and Dr. Louis Nathanson. During my stay at the University of Arizona, Prof. Sudha Ram and Baizheng Yang directed me in the direction of context mediation. A knowledge discovery project in the area of meteorology carried out at the City University of Hong Kong provided valuable insight about the incorporation of domain knowledge from disparate sources. Mervi Ranta from the Helsinki University of Technology contributed some indispensable knowledge on ontologies as part of the Integration in Manufacturing and Beyond project. I would like to thank my colleagues and friends Matthias Baumgarten and Prof. Werner Dubitzky from the University of Ulster, without whom parts of this thesis would not exist. I am grateful to Pat Timmins for proof reading this document. Finally, I would like to thank Claire and Caroline for their patience during the conducting of this treatise and the putting up with all my caprices when things got too stressful. Summary Context Mediation is a field of research that is concerned with the interchange of information across different environments, which provides a vehicle to bridge semantic gaps among disparate entities. Knowledge Discovery is concerned with the extraction of actionable information from large databases. A challenge that has received relatively little attention is knowledge discovery in a highly disparate environment, that is multiple heterogeneous data sources, multiple domain knowledge sources and multiple knowledge patterns. This thesis tackles the problem of semantic interoperability among data, domain knowledge and knowledge patterns in a knowledge discovery process using context mediation. Context fundamentals are introduced, which encompasses the concepts of context identity, semantic values, contextual equivalence, contextual orders, contextual distances, inheritance of contexts and inter-ontology relationships. Based on this foundation, the principles of context mediators for data, domain knowledge and knowledge patterns are outlined, a context mediator prototype is developed and performance tests are carried out. Expanding on these rudimentary elements, context mediation is introduced for data, domain knowledge and knowledge patterns. Contextual data mediation is concerned about semantic conflicts among heterogeneous data sources which are used as input for knowledge discovery. In order to treat …