In this paper, we study the exploration / exploitation trade-off in cellular genetic algorithms. We define a new selection scheme, the centric selection, which is tunable and allows controlling the selective pressure with a single parameter. The equilibrium model is used to study the influence of the centric selection on the selective pressure and a new model which takes into account problem de...

We model the problem of monolingual textual alignment as a Quadratic Assignment Problem (QAP) which simultaneously maximizes the global lexicosemantic and syntactic similarities of two sentence-level texts. Because QAP is an NP-complete problem, we propose a branch-and-bound approach to efficiently find an optimal solution. When compared with other methods and studies, our results are competitive.

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New lower bounds for the quadratic assignment problem QAP are presented. These bounds are based on the orthogonal relaxation of QAP. The additional improvement is obtained by making eecient use of a tractable representation of orthogonal matrices having constant row and column sums. The new bound is easy to implement and often provides high quality bounds under an acceptable computational eeort.

It is the purpose of this paper to propose and discuss certain modifications of the ideas concerning GromovHausdorff distances in order to tackle the problems of shape matching and comparison. These reformulations render these distances more amenable to practical computations without sacrificing theoretical underpinnings. A second goal of this paper is to establish links to several other practi...

We study the quadratic assignment problem (with n variables) from a polyhedral point of view by considering the quadratic assignment polytope that is defined as the convex hull of the solutions of the linearized problem (with n + 2 n 2 n −1 ( ) variables). We give the dimension of the polytope and a minimal description of its affine hull. We also propose a family of facets with a separation alg...

In this paper we develop a model for small scale examination scheduling. Beginning with a formulation of a quadratic assignment problem we show the transformation into a quadratic semi assignment problem and its application to a real world situation. Using simulated annealing we demonstrate the model's ability to generate schedules that satisfy student as well as university expectations.

We consider special cases of the quadratic assignment problem (QAP) that are linearizable in the sense of Bookhold. We provide combinatorial characterizations of the linearizable instances of the weighted feedback arc set QAP, and of the linearizable instances of the traveling salesman QAP. As a by-product, this yields a new well-solvable special case of the weighted feedback arc set problem.

We describe a branch-and-bound algorithm for the quadratic assignment problem (QAP) that uses a convex quadratic programming (QP) relaxation to obtain a bound at each node. The QP subproblems are approximately solved using the Frank-Wolfe algorithm, which in this case requires the solution of a linear assignment problem on each iteration. Our branching strategy makes extensive use of dual infor...