Ontology-Based Query in Heterogeneous & Distributed Data Sources

Abstract-- Information sharing, exchanging and retrieving from heterogeneous data sources not only needs complete data accessibility, but also it needs solving data heterogeneity between these data sources. To solve this rising problems of heterogeneity, a lot of recent work has been done towards solving this issue. This research aims to develop a software system based on ontology to semantically integrate heterogeneous data sources such as XML and RDF to solve some conflicts that occur in these sources. We developed an agent framework based on ontology to retrieve data from distributed heterogeneous data sources. With this technique, user will be able to send a mobile agent with classical input query to a data source. Then the mobile agent will carry the needed module of the global ontology prepared by the user stationary agents and transport itself from the user site to a remote XML or RDF data source. At remote XML data source, stationary agents will transform the heterogeneous XML source into temporary local RDF ontology. The stationary agents in all sources perform a mapping between the local and global ontologies, convert the query to XML or RDF query, execute it and set the results in a suitable form. Finally, the mobile agent will return back with the results. A partial implementation of this framework has been carried out using some modules and libraries of Java, Aglet, Jena an