Ontology-based visualization and navigation in an online digital library

In this paper, we present a novel approach to visualize and navigate the document collection of a DL using ontology. We assume a DL corpus as a network of a large set of information nodes. We use domain ontology to depict the background knowledge organization and map the multimedia information nodes on that knowledge map, in order to make the implicit knowledge organization in a collection explicit. The ontology is automatically created by exploring the Wikipedia knowledge hierarchy, and is delimited to tightly cover the information nodes in the library's collection. We present an abstract view of the knowledge map, clear and concise, which can be progressively ‘zoomed in’ or ‘zoomed out’ to navigate the knowledge space. We place the ontology nodes on the screen, based on their mutual similarity scores for aiding the cognitive process during navigation. The system provides an interactive navigation interface to the users.