Our research is mainly concerned with the knowledge representation language FO(·). This logic extends classical logic logic with inductive definitions, yielding an intuitive and expressive language. This webpage bundles the most important results about FO(·), including inference systems for FO(·), its relation to other formalisms, splitting results, etc.
Our research in some more detail
- Marc Denecker, who is the head of our group, developed Approximation Theory in collaboration with U.Kentucky. Together with the KRR-group and the S.F.U. computational logic group, he developed FO(·). Approximation Theory is a general fixpoint theory for arbitrary operators, i.e., it's a generalization of Tarski's fixpoint theory. It has been succesfully used in the study of non-monotonic reasoning.
- Joost Vennekens researches probabilistic logic programming. He is developer of the language of Logic Programs with Annotated Disjunction (LPADs), and is integrating ideas from FO(·) and from LPADs. Also, he has produced some modularity results.
- Johan Wittocx's research is concerned with approximative reasoning on FO(·) theories. He is also developing techniques for grounding FO(·) based on approximative reasoning.
- Hanne Vlaeminck's research is concerned with propagation techniques for FO(·). She also worked on knowledge-based software engineering.
- Broes De Cat develops revision and optimization techniques for FO(·). Another point of research is the connection between FO(·) modelgeneration and the paradigm of Sat Modulo Theories.
- Dynamic access to all KRR publications: Search engine
- Selected publications: a brief guide to the most relevant papers for certain subjects.
- Seminars given by KRR members.
- Joost visited Michael Gelfond at KR Lab of Texas Tech University in December 2005-January 2006.
- Marc and Maarten visited Ilkka Niemelä at TCS of Helsinki University of Technology in October 2005.
- Álvaro Cortés work studied databases with local forms of closed world assumptions: semantics, complexity and approximate query answering methods. Alvaro obtained his PhD.
- Nikolay Pelov's research dealt with semantics of logic programs with aggregate expressions. His PhD thesis proposes a series of semantics for logic programming with aggregates. This work is used in FO(·).
- Bert Van Nuffelen developed the A-system, still one of the most performant abductive systems for abductive logic programming. Here is his PhD thesis.