Section: Scientific Foundations

Constraint solvers

Our domains of application use quite different constraint systems:

• finite domains (bounded natural numbers): primitive constraint of some finite domain membership, numerical, symbolic, higher order and global constraints;

• reals: polyhedral libraries and Simplex algorithm for linear constraints and interval methods otherwise;

• terms: subtyping constraints and ontologies;

• temporal constraints: CTL and LTL formulae, either propositional or with numerical constraints.

The project works on constraint resolution methods and their cooperation. The main focus is the declarativeness of the constraint solver (e.g. implemented by CHR rules), the efficiency of constraint propagation methods, the design of global constraints and the combination of constraint propagation with heuristic search.