Lower Bounds for the Quadratic Assignment Problem via TriangleDecompositionsStefan
نویسندگان
چکیده
We consider transformations of the (metric) Quadratic Assignment Problem (QAP), that exploit the metric structure of a given instance. We show in particular, how the structural properties of rectangular grids can be used to improve a given lower bound. Our work is motivated by previous research of G.S. Palubetskes, and it extends a bounding approach proposed by J. Chakrapani and J. Skorin-Kapov. Our computational results indicate that the present approach is practical and it has been applied to problems of dimension up to n = 150. Moreover, the new approach yields by far the best lower bounds on most of the instances of metric QAPs that we considered.
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