Research Of Approach To Semantic Web Portal Development

The current Web is evolving to the Semantic Web, therefore research of the next generation of Web portals (i.e. Semantic Web portals, Semantic Web technologies enabled Web portals) technology is a natural development trend.Early Semantic Web portal development focuses on bottom-up methods, which make use of ontology technology (and Web services technology) to reconstruct (emigrate or upgrade) current Web portals to Semantic Web portals. However, the built-in limitations of conventional Web development technologies, which are used to develop current Web portals, make the reconstructing task so difficult that the reconstructed Semantic Web portals cannot be ideal. Currently, Semantic Web ontology technology is becoming mature, related academic community and industrial community have presented several methodologies, software engineering frameworks and tool-suits to develop Semantic Web portals in a top-down way. But the Semantic Web portals developed by such methodologies, frameworks and tool-suits also cannot achieve the goals of an ideal Semantic Web portal. In the background, this thesis researches and proposes a software engineering framework and methodology called CASE4SWPD for the development of an ideal Semantic Web portal in a top-down way, researches a key process within the framework which is domain ontology based relational database (RDB) schema design, and designs and develops a CASE tool prototype called O2DDesigner for the key process.According to a set of predefined conversion rules from ontology to RDB schema, an conversion algorithm and the XML representation format for element mappings between ontology and RDB schema (Onto-RDB), O2DDesigner automatically generates RDB schema (SQL DDL statements) and Onto-RDB element mappings data in XML format based on the inputted domain ontology. O2DDesigner provides the portal engineer with a friendly human-machine interactive interface. It can parse and visualize an OWL DL ontology, automatically generate and output RDB schema DDL statements and Onto-RDB element mappings XML file according to portal engineer's choice of RDBMS type.A typical case study validates the feasibility of the conversion algorithm, the reasonableness of Onto-RDB element mappings XML format, and the effectiveness of the implemented prototype tool. And a typical application of the results of O2DDesigner in a Semantic Web portal shows the relationship between domain ontology based RDB schema design and CASE4SWPD framework.