Pierre Hansen
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369 résultats — page 9 de 19
We consider the problem of separating two sets of points in an <i>n</i>-dimensional real space with a (hyper)plane that minimizes the sum of <i>L<sub>p</sub...
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In this paper we develop a Variable neighborhood search (VNS) heuristic for solving Mixed-Integer Programs (MIP’s). It uses CPLEX, the general-purpose MIP s...
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An upper bound is given on the variance of degrees of graphs with <i>n</i> vertices, <i>m</i> edges and maximum degree Δ. Particular cases of chemical...
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The algebraic connectivity <i>a(G)</i> of a graph <i>G = (V,E)</i> is the second smallest eigenvalue of its Laplacian matrix. Using the AutoGraphiX (AGX) sys...
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Chemical graphs, as other ones, are <i>regular</i> if all their vertices have the same degree. Otherwise, they are <i>irregular</i> and it is of interest to...
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The uniting feature of combinatorial optimization and extremal graph theory is that in both areas one should find extrema of a function defined in most...
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Conjectures in graph theory have multiple forms and involve graph invariants, graph classes, subgraphs, minors and other concepts in premisses and/or conclu...
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Computer-assisted and automated conjecture-making in graph theory is reviewed, focusing on the three operational systems GRAPH, Graffiti and AutoGraphiX (AGX...
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Two ways for bounding <i>n</i>-variables functions over a box, based on interval evalu- ations of first order derivatives, are compared. The optimal Baumann...
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We consider the bilevel uncapacitated facility location problem with user preferences. It is known that this model may be reformulated as a one-level locati...
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The multiprocessor scheduling problem with communication delays that we consider in this paper consists of finding a static schedule of an arbitrary task gra...
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In this exploratory study, a segmentation analysis of a shopping mall’s customers is conducted according to the activities they performed during their visit,...
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This paper examines the convergence properties of two well-known heuristics: variable neighborhood search (VNS) and random multistart local search (MLS). Bot...
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When applying the 2-opt heuristic to the travelling salesman problem, selecting the best improvement at each iteration gives worse results on average than se...
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The berth allocation problem is to allocate space along the quayside to incoming ship at a container terminal in order to minimize some objective function....
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The berth allocation problem is to allocate berths (i.e., sections of the quayside) to ships arriving in a container port in order to minimize the sum of the...
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Bimatrix and polymatrix games are expressed as parametric linear 0-1 programs. This leads to an algorithm for complete enumeration of their extreme equilibri...
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Goal Programming with fractional objectives can be reduced to mathematical programming with a linear objective under linear and quadratic constraints, thus...
référence BibTeXThe Minimum Diameter Octagon with Unit-Length Sides: Vincze's Wife's Octagon is Suboptimal
This paper answers a query of S. Vincze (Acta Univ. Szeged, Sect. Sci. Math. 12 A (1950) 136-142): find the convex octagon with unit-length sides and minim...
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Variable Neighborhood Search (VNS) is a recent metaheuristic, or framework for building heuristics, which exploits systematically the idea of neighborhood ch...
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