T2: Ontology Design Patterns and Problems: Practical Ontology Engineering using Protege-OWL
(Alan Rector, Guus Schreiber, Natalya F. Noy, Holger Knublauch and Mark A. Musen)

The Task Force on Ontology Engineering and Patterns of the W3C working group on Semantic Web Best Practices and Deployment will have completed most of its work by the time of the conference. The Task Force has already produced a series of first working draft notes on common ontology design patterns. These patterns analogous to the programming design patterns used by software engineers are directly influencing the development of the Protégé-OWL ontology development environment and its extensions by the CO-ODE project.

This tutorial will introduce attendees to the concept of ontology patterns and discuss key patterns developed by the Task Force and others. Example patterns include quantities and units, value partitions, n-nary relations, problems of distinguishing classes and individuals, the choice between representing relationships as classes or properties, and qualified cardinality restrictions. (The final choice of issues will be driven by the results of the Task Force.)

The tutorial will provide practical hands-on experience with the patterns using the Protégé-OWL tools and CO-ODE extensions. The style of the tutorial will be lecture demonstration. The software and examples will be made available in advance and attendees will be encouraged to gain hands on experience and explore the trade-offs between alternative patterns by working through the examples on their laptops. (See http://protege.stanford.edu and http://www.co-ode.org)

The quality, availability and breadth of coverage of ontologies will be a major factor in determining the success of the Semantic Web. Patterns and tools to make it easier to develop high quality ontologies is therefore crucial to the Semantic Web Development.

However, the idea of ontology patterns is relatively new. Many controversies remain. Ample time will be provided for feedback, questions and discussion. Three of the proposers are members of the Task Force, and one of them, Guus Schreiber, chairs the W3C Working Group.