Semi Quadratic Assignment Problem
نویسنده
چکیده
Changing the QAP's hard definition such that the facilities M are allowed to be mapped by a (single-valued, not necessarily injective) function π into the set of possible locations Y subject to a relation Π, π ⊆ Π, it arises the Semi-QAP that might be regarded as a relaxation of the QAP. In contrast to the Tree-QAP (flow graph F is a tree) the corresponding Semi-Tree-QAP is solvable in polynomial time. This enables us to show that there is a constructive approximation algorithm, here called R2, solving the Semi-QAP with O(k⋅p) guaranteeing an ε = (Cappr – Copt) / Copt = |F| +1– |M| (Semi-QAP's optimal cost Copt, and approximate cost Cappr).
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