Knowledge Representation and Reasoning Group

The Knowledge Representation and Reasoning group is one of the four groups within the Department of Artificial Intelligence.

Table of Contents

• General Description
• Members of the KR&R Group
• Research Areas of the KR&R Group
• Projects
• Master's Projects Page
• Resources
• Route Description

General Description

The KR&R group investigates modelling and representation of different forms of knowledge and reasoning, as found in a large variety of AI systems. We have an interest in both applications and theory. We study theoretical properties of knowledge representation and reasoning formalisms, but are also involved in developing practical knowledge-based systems. Recently, we have been very active in developments around the Semantic Web.

See this guide with directions on how to reach us.

Members of the KR&R Group

• Stefano Bocconi
• Paul Groth
• Christophe Guéret
• Frank van Harmelen
• Rinke Hoekstra
• Zhisheng Huang
• Szymon Klarman
• Spyros Kotoulas
• Krystyna Milian
• Stefan Schlobach
• Ruud Stegers
• Gaston Tagni
• Annette ten Teije
• Jacopo Urbani
• Shenghui Wang

The group is headed by Prof. Frank van Harmelen.

Previous Members of the KR&R Group

• Eyal Oren (now at McKinsey)
• Antoine Isaac (now at Web and Media Group at the VU)
• Lourens van der Meij (now at Web and Media Group at the VU)
• Wouter van Atteveldt (now at Dept. of Communication Studies at the VU)
• Michel Klein (now at Agent Group at the VU)
• Ronny Siebes (now at Web and Media Group at the VU)
• George Anadiotis (now at IMC Technologies)
• Zharko Aleksovski (now at Philips Research)
• Holger Wache (moved to the University of Applied Sciences Northwestern Switzerland (FHNW))
• Marjolein van Gendt
• Andreas Hess
• Radu Serban
• Wouter van Steenbergen
• Heiner Stuckenschmidt (now at Universitat Mannheim, Germany)
• Marta Sabou (now at Knowledge Media Institute, UK)
• Maarten Menken (now at LogicaCMG)
• Jeen Broekstra (now at Technische Universiteit Eindhoven)
• Jan Broersen (now at University of Utrecht)
• Perry Groot (now at University of Nijmegen)
• Mar Marcos (now at University of Castelon)

Visitors to the KR&R Group

• Grigoris Antoniou (autumn 2003)
• Edgard Costa Oliveira (autumn 2003–summer 2004)
• Maria Taboada Iglesias (February 2005)
• Stefano Zanobini (half a year starting from October 1, 2004)
• Jeff Pan (July 2005)
• M. Yatskevich (July 2005)
• Peter Dolog (September - October 2005)
• Raul Garcia Castro (February - April 2007)
• Dongmo Zhang (August -September 2007)
• Wei Hu (November 2007 - April 2008)
• Cássia Trojahn dos Santos (February - April 2008)
• Yi Zeng (May - June 2009)
• Václav Belák (December 2009)

Research Areas of the KR&R Group

For each of our research areas, we give a brief description, we list the people active in this area, and we give one or two papers that are characteristic for our work. More details on all our papers on the home-pages of the individual members.

• Approximate reasoning: Classical logic-based reasoning provides either a correct answer or no answer at all. We study alternative forms of reasoning which provide approximate answers under suboptimal circumstances. This allows for more gradual correctness criteria, and can be exploited in anytime algorithms.
  People: Perry Groot, Annette ten Teije, Frank van Harmelen, Heiner Stuckenschmidt
  Papers: ECAI'00 about anytime reasoning; KR'00 about approximate diagnostic reasoning.
  
• Medical protocols: Medical protocols describe a medical procedure for a given category of patients. Such protocols are widely seen as a promising means to simultaneously improve the quality of health-care while reducing the costs. We study a number of KR languages for representing such protocols, and perform various forms of reasoning with such protocols (verification, critiquing, configuration etc.).
  People: Mar Marcos, Annette ten Teije, Frank van Harmelen
  Papers: AIME'01 about using critiquing to improve protocols; AIM'99 about the protocol language ProFORMA.
• The Semantic Web: The growth of the Web has resulted in a very large body of weakly structured information that is available on-line. The Semantic Web is an effort to make the meaning of this information accessible not only to humans, but also to machines. This will help searching, navigating, visualising and maintaining such information, and generally using the web to do things, instead of only to find things.
  People: Jeen Broekstra, Frank van Harmelen, Marta Sabou, Heiner Stuckenschmidt
  Papers: WWW'01 about extending RDF Schema into a proper ontology language; IEEE-IS'01 about OIL, a web-based ontology-language we designed, which is currently the basis for a W3C standard.

Projects

We participate in the following projects:

	BEST		LarKC (Large Knowledge Collider)
	SOKS (Self-Organising Knowledge Systems)		Chinese WordNet

Students looking for a master's project can take a look at the master's projects page of the KR&R group.

Previous Projects

	STITCH (Semantic Interoperability To access Cultural Heritage)		Knowledge Web
	OpenKnowledge		Protocure: Improving medical protocols by formal methods
	SEKT (Semantically Enabled Knowledge Technologies)		IBROW: Intelligent Brokering Service for Knowledge-Component Reuse on the World Wide Web
	On-To-Knowledge: Content-driven knowledge management through evolving ontologies		The OntoWeb Network
	SWAP (Semantic Web And Peer-to-peer)		WonderWeb: Infrastructure for the Semantic Web
	I-Catcher (Intensive-Care Access to Terminology & Course of Health Exploration and Retrieval)

Resources

• To support the development of semantic integration tools and methods, suitable test data is needed. Many schemas and ontologies have been developed in different domains, but what is often needed is a set of ontologies about the same subject. For this purpose we gathered about 47 test ontologies that students produced, all covering the same domain (the university department). On average the ontologies contain 30 classes, 50 relations and 200 instances. The data is represented in RDF and stored in the Sesame system, so that it can easily be queried using SeRQL, RQL and RDQL.
• JClips is a piece of software that allows programmers to use CLIPS in combination with Java by embedding the CLIPS engine in Java applications.
• The Prolog Sesame Client module enables programmers to connect to the Sesame system from inside Prolog and perform queries. The results can be asserted as Prolog facts to allow further reasoning.
• The DIG2TeX translator allows a user to translate an ontology in the DIG format into a human readable LaTeX Format. An example ontology can be found here and its LaTeX translation can be found here.
• The Extended DIG Description Logic Interface for Prolog (XDIG) is a logic programming infrastructure for the Semantic Web. XDIG supports both DIG clients and DIG servers. As a DIG client, the Prolog programs can call any external DL reasoner which supports the DIG DL interface. As a DIG server, the Prolog programs can serve as a DL reasoner, which can be used to support additional DL reasoning processing.
• PION: a Reasoner/System for Processing Inconsistent ONtologies. The classical entailment in logics is explosive: any formula is a logical consequence of a contradiction. Therefore, conclusions drawn from an inconsistent ontology by classical inference may be completely meaningless. An inconsistency reasoner is one which is able to return meaningful answers to queries, given an inconsistent ontology. PION is a reasoner/system which can return meaningful answers to queries on inconsistent ontologies. PION is powered by XDIG, an extended DIG Decription Logic Interface for Prolog, in particular, for SWI-Prolog. PION supports TELL requests both in DIG and in OWL, and ASK requests in DIG.
• MORE: Multi-Version Ontology REasoner is a multi-version ontology reasoner which is based on a temporal logic approach. MORE supports temporal reasoning queries, ontology comparison queries, version retrieval queries, relative/absolute version numbering queries. MORE supports multiple ontology language, including DIG data format and OWL.