Contact: Leon Deligiannidis

Paged Graph Visualization

I. Goal

II. Requirements

III. Project Description

Paged Graph Visualization (PGV) is a new user-centered, semi-autonomous visualization tool for RDF data exploration, validation and examination. PGV consists of two main components: the PGV visualizer, which is the front-end of PGV, and the BRAHMS data-store, which is our high performance main-memory RDF storage system. Unlike th e existing graph visualization techniques which attempt to display the entire graph, PGV has been designed for the incremental, semantics-driven exploration of very large RDF ontologies. A novel, Ferris-Wheel-like visualization technique is used to explore the so called hot spots in the graph, i.e. nodes with large numbers (hundreds) of immediate neighbors. In response to the user-controlled, semantics-driven direction of the exploration, the PGV visualizer obtains the necessary sub-graphs from BRAHMS and enables their incremental visualization without having to rearrange the previously laid out sub-graphs. PGV and BRAHMS communicate via the HTTP protocol and to provide the necessary on-line response times, BRAHMS is connected to the Web server via the Fast-CGI interface which eliminates the need of restarting the BRAHMS process at every request. Additionally, PGV has been enhanced with a speech recognizer and a speech synthesizer.

My PGV site that I update frequently.

Leonidas Deligiannidis, Krzysztof J. Kochut, Amit P. Sheth User-Centered Incremental Data Exploration and Visualization Technical report: PGV

IV. Design