ERCIM Working Group
on Constraints

by Krzysztof R. Apt

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Constraints have recently emerged as a research area that combines researchers from a number of fields, including Artificial Intelligence, Programming Languages, Symbolic Computing and Computational Logic.

Constraint networks and constraint satisfaction problems have been studied in Artificial Intelligence starting from the seventies. Systematic use of constraints in programming has started in the eighties. In constraint programming the programming process consists of a generation of requirements (constraints) and solution of these requirements, by specialised constraint solvers.

Constraint programming has been successfully applied in numerous domains. Recent applications include computer graphics (to express geometric coherence in the case of scene analysis), natural language processing (construction of efficient parsers), database systems (to ensure and/or restore consistency of the data), operations research problems (like optimization problems), molecular biology (DNA sequencing), business applications (option trading), electrical engineering (to locate faults), circuit design (to compute layouts), etc.

Current research in this area deals with various foundational issues, with implementation aspects and with new applications of constraint programming. The concept of constraint solving forms the central aspect of this research.

This working group brings together ERCIM researchers that are involved in research on the subject of Constraints.

Its aims are:

• to promote research on this subject within the ERCIM institutions
• facilitate the exchange of information
• coordinate efforts in technology transfer
• facilitate the exchange of researchers for short and long visits.

Currently, the following institutions participate in the Working Group through the mentioned representatives:

• CWI, Amsterdam: Krzysztof R. Apt, apt@cwi.nl (chairman); Robert van Liere, robertl@cwi.nl; Elena Marchiori, elena@cwi.nl (secretary)
• INRIA, Rocquencourt: Philippe Codognet, philippe.codognet@inria.fr
• INRIA Lorraine, Nancy: Claude Kirchner, Claude.Kirchner@loria.fr
• SICS, Kista, Sweden: Seif Haridi, seif@sics.se
• IEI-CNR, Pisa: Patrizia Asirelli, asirelli@iei.pi.cnr.it
• VTT Information Technology, Espoo, Finland: Eero Hyvonen, eero.hyvonen@vtt.fi
• CLRC, Oxon, UK: Stephen Cook, S.Cook@rl.ac.uk
• Universita di Pisa: Ugo Montanari, ugo@di.unipi.it
• Universidad Politecnica de Madrid (UPM): Manuel Hermenegildo, herme@sol.dia.fi.upm.es

Research groups of other ERCIM institutes that are interested in joining the working group are requested to contact the chairman. Information on the web:
http://www.cwi.nl/projects/ercim-wg.html

Please contact:
Krzysztof R. Apt - CWI
Tel: +31 20 592 4135
E-mail: apt@cwi.nl
or Elena Marchiori - CWI
Tel: +31 20 592 4075
E-mail: elena@cwi.nl