Practical Reasoning with OWL and DL-Safe Rules

Half-day tutorial at the 3rd European Semantic Web Conference, ESWC 2006.


We present an introduction to reasoning with the Web Ontology Language OWL and DL-safe rules using the KAON2 OWL reasoner. The tutorial is targeted at ontology engineers and researchers in the general area of the semantic web and does not require any in-depth background knowledge on logical aspects of semantic web reasoning. We will briefly introduce OWL and description logics, corresponding reasoning tasks, visualisations using Protégé, and practical usage of KAON2. A short overview of tableau reasoning is followed by a closer look at the KAON2 architecture and its query mechanisms. We introduce DL-safe rules and show how they can be used to recover from modelling restrictions imposed by OWL. The tutorial, which will be driven by examples and demonstrations, will close with examples of data integration using KAON2. Participants will have the chance to take part in hands-on exercises. The required software will be distributed in advance.


The tutorial will take place at June 11 2006 at ESWC06, Budva, Montenegro.

9:00-10:30 Part 1: Theory of reasoning with OWL and rules (Presenter: Markus Krötzsch)

  1. Description logics
  2. The KAON2 reasoner
  3. Conjunctive queries
  4. Semantic Web rules
  5. Outlook

10:30-11:00 Coffee Break

11:00-12:30 Part 2: Practical applications of OWL and rules (Presenter: Peter Haase)

  1. Sample application: Natural Language Question Answering
  2. Using KAON2
  3. Hands-on session

Relevant Course Material

Tutorial Slides

The KAON2 System

KAON2 API Javadoc


Protege 3.1

SWRC Ontology


Corresponding author: Peter Haase