Section: New Results

Rule-based Modeling of Constraint Satisfaction Problems

Participants : François Fages, Curtis Fonger, Julien Martin, Thierry Martinez, Surinderjeet Singh.

Rules2CP [29] is a rule-based modeling language which allows easy modelling of constraint satisfaction problems, together with specifications for search strategies and heuristic choice criterias. In [14] , we describe the language and its compilation to constraint programs with a term rewriting system.

The expressiveness and effectiveness of Rules2CP have been illustrated through the development of the Packing Knowledge Modeling Language PKML as a library on top of Rules2CP, dedicated to bin packing problems. PKML language is used in the FP6 Strep Net-WMS to study and solve higher-dimensional bin packing problems and placement constraints, including common sense, physical and industrial requirements expressed by rules [28] , [27] , [23] , [32] .

Furthermore, in [37] , we look at the application of Rules2CP to solve Open-Shop Problem, which is at the core of many scheduling problems. In this approach we are able to solve many of the Open Shop instances which have only been closed very recently with minimal effort.