Research On CHL Extended Ontology Mappings Updating

With the advent of the cloud, the Internet enters into the era of massive data.Thanks to the development of science and technology, the definition and expressionof the information on the Internet evolves from non-formatted or semi-formatted tothe present status based on ontology, from the original HTML language to the currentRDF and DAML language. However, the spontaneous ontology definition anddifferent social and cultural backgrounds, term specification habits, understandings ofontology structure of operators result in various manifestations in spite of the samedomain knowledge, thus leads to ontology heterogeneous, which severely limits datasharing and integration.Ontology mapping can solve the problem of ontology heterogeneous effectively.However, most existing ontology mapping study only focused on mapping methoditself and a lack of ontology conciliation analysis in practical dynamic environmentresults in a poor efficiency when the existing ontology mapping method put intopractice.For addressing this issue, the main work of this article is the research of theupdating of ontology mappings in dynamic environment. On the basis of CHL inwhich ontology changes history stores, an ontology mapping method with changehistory ontology extended is proposed. The extended system makes versioning,history recovery, change tracking and visualization come true. The main researchwork is as follows:1. A Roll Back/Roll Forward algorithm is proposed in order to solve the problemof ontology recovery in case of errors in ontology evolution. In this algorithm, allchanges belonging to a ChangeSet are sorted in a reverse chronological order and areimplemented in the inverse manner on the loaded model, the evolved ontology modelsand change history logs are stored in the meantime. Experimental results show thatthe algorithm can accurately make the evolved ontology back to the original state.2. Visualization of ontology evolution is proposed and implemented withTouchGraph in the paper. Visualization contributes to visualize the details in ontologychanges. We have extended the TouchGraph API for graph drawing in order tovisualize the graph view of the ontology structure. Resources, such as classes, aredepicted as nodes. These nodes are connected through properties, which are depicted as edges. The direction of an edge depicts the direction of the relationship among thenodes.3. An ontology mapping method with change history extended is proposed。Weenvisioned our proposed framework as an enabling component for the ontologyeditors. The framework itself does not provide ontology editing services, rather itimplements listeners to monitor and log changes. The framework was implementedfor ontologies defined in rdfs and all variants of OWL. Experimental results show thatthis method offers the benefits of re-establishing mappings among the updatedontologies. It drastically reduces the time required for updating mappings amongontologies.