Aspects of ontology visualization and integration
Joelia Borisnova Dmitrieva · Leiden Repository (Leiden University) · 2011
In this thesis we will describe and discuss methodologies for ontology visualization and integration. Two visualization methods will be elaborated. In one method the ontology is visualized with the node-link technique, and with the other method the ontology is visualized with the containment technique. To that end, first a method is introduced that transforms an OWL ontology to a graph structure, and subsequently the requirements are discussed that have been used as a guidance during the development of the visualization approach. In the node-link technique, it is investigated how different geometrical representations can contribute to the presentation of an ontology. The geometrical representations are applied in such a way that one can switch between them. The outcome makes the visualization more flexible as one is not restricted to one particular representation at a time. The containment technique has, to date, not been applied in 3D for ontology visualization. The 3D approach for the containment technique is elaborated and for the 3D context, projection of the ontology data on a sphere is developed. This approach is augmented with semantic zoom technique that allows easily control the level of detail in the visualization. The spherical alternative to containment visualization is new to the ontology visualization approach. Ultimately, using the transformation of the ontology to the graph, visualization engines can be developed with which one can seamlessly switch from the node-link to the containment technique. The developments described in this thesis are a prelude to that. Two integration approaches will be introduced. The first one is devoted to visualization of ontological context generated from different ontologies on the basis of a concept of interest, and the second one is devoted to creation of a new ontology on the basis of modules extracted from different ontologies.