Research On Web Semantic Query And Reasoning

The goal of the Semantic Web is to develop enabling standards and technologies designed to help machines understand more information on the Web so that they can support richer discovery, seamless data integration, improved navigation, and automation of tasks.One challenge for the Semantic Web is to support semantic query and reasoning in such an open, distributed, dynamic, heterogeneous environment. This thesis is intended to contribute on this issue, and mainly involves the following notions.- Research on Grid Architecture for Semantic WebBased on concepts and ideas from Grids, an open knowledge service architecture, called knowledge grid, is proposed, better enabling web semantic query and reasoning. We elaborate on three fundamental elements of knowledge grid, they are ontology service, semantic query service and semantic registration service.- Research on Answering Semantic Query Using Views in Semantic WebFirst, formal definitions on RDF-based semantic query and semantic view are given. Second, based on the Open World Assumption, a proof on the equivalence between the problem of answering RDF-based semantic queries using semantic view and the problem of RDF-based semantic query subsumption inference is presented. The algorithms for RDF-based query subsumption inference and query rewriting are also introduced.- Research on Web ReasoningBased on the research on contextual reasoning and distributed description logic, a distributed tableaux reasoning algorithm that support context-based web reasoning is proposed. Because it is hard to reason by rigorous logic-based approach in such an open web environment, an approximation-based approach for web reasoning is also presented. We define a RDF-based Case Markup Language (CaseML) for experience knowledge representation and develop a generic architecture for the case based reasoning in the open, distributed environment with the emphasis on the integration of case knowledge with web ontologies.- Design and Implementation of Q3, a Semantic Query LanguageQ3 is a sub language of N3 and carries the aims of improving readability, accurately capturing the semantic of queries, formulating query on database resources using RDF/OWL semantic. Detail introduction on the design strategy , formal syntax , and model-theory semantic of Q3 and its implementation in Dart Database Grid are also given.- Design and Implementation of DartGrid, a Prototype System of Semantic-based Database GridWe introduce an operational prototype called Dart Database Grid, which employs Globus as its development and deployment platform, and also takes advantages of Semantic Web standards and techniques to provide a semantic-heterogeneity solution capable of deployment at web-scale. The core components are introduced, they are: semantic browser, ontology service , semantic query service,semantic registration service, database grid service. We note that DartGrid has been applied in web-based data sharing and database integration for Traditional Chinese Medicine (TCM)...