Efficient Pruning Technique Based on Linear Relaxations

摘要

This paper extends the Quad-filtering algorithm for handling general nonlinear systems. This extended algorithm is based on the RLT (Reformulation-Linearization Technique) schema. In the reformulation phase, tight convex and concave approximations of nonlinear terms are generated, that's to say for bilinear terms, product of variables, power and univariate terms. New variables are introduced to linearize the initial constraint system. A linear programming solver is called to prune the domains. A combination of this filtering technique with Box-consistency filtering algorithm has been investigated. Experimental results on difficult problems show that a solver based on this combination outperforms classical CSP solvers.