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69 Cahiers pour l'année 1999

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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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This paper presents a decomposition approach for the solution of the dynamic programming formulation of the Unit Loading Problem in hydroplant management. T...

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In this article we propose a model for the topological design problem of multitechnology networks that includes the location of switches and their port conf...

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Inspired by previous results on asymptotic minimax estimation for a ball of increasing radius in R<sup><i>n</i></sup>, we study the analogous problem for do...

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There is an increasing interest for efficient synthesis methods (routing and dimensioning) of large and robust multi-service networks. In the case of ATM ne...

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This paper presents a survey of the research on the Vehicle Routing Problem with Time Windows (VRPTW), an extension of the Capacitated Vehicle Routing Probl...

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It is shown that a geometrically planar fusene is uniquely determined by its boundary edge code. Surprisingly, the same conclusion is not true in general b...

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In classical module theory, a module over a principal ideal domain may be split into the direct sum of a free module and a torsion module. This decompositio...

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We study several formulations of the channel assignment problem in an FDMA network as a linear integer 0-1 program. We consider the objective of minimizing...

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This paper deals with the class of continuous-time linear systems with Markovian jumps. We assume that jump rates are controlled. Our purpose is to study th...

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This is a review article on lattice methods for multiple integration over the unit hypercube, with a variance-reduction viewpoint. It also contains some new ...

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In this paper, we prove that the maximum <i>k</i>-club problem defined on an undirected graph is NP-hard. We also give an integer programming formulation f...

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The Joint Replenishment Problem (JRP) is a multi-item inventory problem. The objective is to develop inventory policies that minimizes the total costs (comp...

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L'affectation de type d'avion aux vols consiste à déterminer, pour chaque arc de vol, le type d'avion qui lui sera affecté de façon à maximiser les profits ...

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A new local search heuristic, called J-MEANS, is proposed for solving the minimum sum-of-squares clustering problem. The neighborhood of the current solut...

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This article is a survey of heuristics for the <i>Vehicle Routing Problem</i>. It is divided into two parts: classical and modern heuristics. The first pa...

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Given a set of logical sentences and probabilities that these sentences are true, the probabilistic logic problem consists in determining whether these prob...

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We present a method for the integral representation of local and global diffeomorphisms between subsets of <img src="G9942-1.gif" align=bottom> and <img src...

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The paper identifies the strategic effects of learning-by-doing in presence of unintended spillovers of production experience. In a two-stage game an incum...

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The definition of a fullerene as a cubic polyhedron made up entirely of pentagons and hexagons is compatible with a huge variety of isomeric forms for struc...

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The recent Variable Neighborhood Search (VNS) metaheuristic combines local search with systematic changes of neighborhood in the descent and escape from loc...

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Fusenes are simply connected, geometrically planar or non-planar polyhexes. Enumeration of such systems with up to 20 hexagons, <i>i.e.,</i> a set 4000 tim...

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This paper presents an exact approach for solving the simultaneous vehicle and crew scheduling problem in urban mass transit systems. We consider the single...

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We pursue the study of concavity cuts for the disjoint bilinear programming problem. This optimization problem has two equivalent symmetric linear maxmin r...

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Pricing Asian options based on the arithmetic average, under the Black and Scholes model, involves estimating an integral (a mathematical expectation) for w...

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This paper focuses on accelerating strategies used in conjunction with column generation to solve Vehicle Routing and Crew Scheduling problems. We describ...

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The well-known Undirected Rural Postman Problem is considered and a binary linear problem using new dominance relations is presented. Polyhedral properties ...

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In recent years several <i>metaheuristics</i> have been proposed for the <i>Vehicle Routing Problem</i>. This article reviews the main metaheuristics for th...

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Over the last thirty-five years several heuristics have been proposed for the <i>Vehicle Routing problem</i>. This article reviews the main classical heuris...

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Let <i>G</i> be a simple graph and <i>C</i> and <i>D</i> two proper colourings of <i>G</i>. The problem of colour switching consists of finding a sequence ...

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In this paper we deal with the problem of how to expand MANs (Metropolitan Area Networks) in a cost-effective way. We first propose a mathematical programmi...

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This note determines a rule to share a surplus gained when two countries or regions agree to coordinate their policies to reduce downstream pollution. An in...

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We study the solution of combinatorial problems with the column generation techniques when there is a very large number of both variables and constraints. ...

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Treatment of imprecise probabilities within the probabilistic satisfiability approach to uncertainty in knowledge-based systems is surveyed and discussed. ...

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The paper considers two neighboring countries wishing to make a joint effort to control pollution emission. We use a differential game model that includes ...

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This paper deals with the problem of how to update telecommunication networks economically. We first propose a mixed integer programming model that includes...

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In this article we propose a mixed 0-1 linear programming model for the topological network design problem with modular switches such as the ones that will ...

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Il est généralement reconnu que le processus de découpage électoral doit être à l'abri du gerrymandering et de l'intervention politique. L'utilisation de mé...

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The spatially inhomogeneous smoothness of the non-parametric density or regression-function to be estimated by non-parametric methods is often modelled by B...

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Coupling with the Modified-Grid Unconstrained Optimization Algorithm we introduced in our previous paper (Cheung and Ng, 1995), we have been able to develop...

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We consider an asymmetric duopoly producing a homogeneous commodity and facing a competitive demand. Our model incorporates two asymmetries. The first one i...

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This paper aims to provide an answer to the still open question, namely who should, if any, lead a marketing channel? To achieve this objective, we conside...

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The purpose of this article is to formulate and solve a shortest loop problem associated with the design of material flow handling systems in factories. Th...

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By means of the variable neighborhood search algorithm, a newly designed heuristic approach to combinatorial optimization, we established the structure of t...

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Given a set of <i>m</i> observations on <i>n</i> variables, an 0(<i>mn</i><sup>2</sup>) algorithm is proposed to find a basis of all affine relations betwee...

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The probabilistic satisfiability problem consists, given <i>m</i> logical sentences, with their probabilities to find if they are coherent, and if it is the...

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This paper deals with the optimal production control problem in a stochastic two-machine flow shop. Our aim is to develop approximation techniques for deriv...

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Cellular manufacturing is a promising approach for grouping efficiency in manufacturing systems. Although this problem has been extensively studied in the ...

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We study the problem of allocation over time of total cost incurred by countries in a cooperative game of pollution reduction. We compute the characteristi...

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Given a network modeled by a probabilistic graph <i>G =</i> (<i>V,E</i>) with bounds on the operation probabilities of edges and of pairs of edges, the seco...

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In a graph <i>G</i>, a <i>k-club</i> is a vertex set inducing a subgraph of diameter <i>k</i>. These structures play an important role in several applicati...

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We discuss the relationship between probabilistic logic and <img src="pi.gif" align=bottom>-CMS. Given a set of logical sentences and probabilities, the ou...

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A hedger of a contingent claim may decide to partially replicate on some states of nature and not on the others: A partial hedge initially costs less than a...

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We present a survey of nondifferentiable optimization problems and methods with special focus on the analytic center cutting plane method. We propose a self...

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Solving exactly large instances of the channel assignment problem often requires to solve large linear programs with respect to the number of columns or row...

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The recently developed Variable Neighborhood Search (VNS) meta-heuristic for combinatorial and global optimization is outlined together with its specializat...

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The chemical trees on <i>n</i> vertices (= molecular graphs representing alkanes with <i>n</i> carbon atoms) with minimal, second-minimal, third-minimal, ma...

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We consider a resource constrained shortest path problem in acyclic graphs, where resource windows are associated with the arcs, while lower and upper thres...

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An exact algorithm is proposed for minimum sum-of-squares nonhierarchical clustering, i.e., for partitioning a given set of points from Euclidean <i>m</i>-s...

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We present a branch and cut algorithm that yields in finite time, a globally <img src="epsilon.gif" align=bottom>-optimal (with respect to feasibility and o...

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Rotating schedules are commonly used in a number of industries and public services where employees work round the clock, seven days a week. Several rules g...

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In this paper we study the role of order releases and product mix coordination in a complex manufacturing line with batch processors. We develop a planning ...

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Le problème de plus court chemin avec contraintes de ressources consiste à trouver un chemin d'un point origine à un point destination de coût minimum et re...

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Roadway snow and ice control (RSIC) is one of the most complex and fascinating venues for arc routing applications. Arc routing problems occur in several di...

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In this paper, the mixed \(H_2 / H_\infty\) control problem for continuous-time Markovian jumping linear systems using state-feedback control is considere...

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This paper deals with the inventory-production control problem where the produced items are assumed to deteriorate with a rate that depends on the demand ra...

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The cell-loss ratio at a given node in an ATM switch, defined as the steady-state fraction of packets of information that are lost at that node due to buffe...

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In this paper we develop robustness bounds for sampled-data linear time-delay systems. The uncertainty is assumed to be on both the <i>A</i> and <i>B</i> ma...

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Let <i>G</i> be a connected graph and let <i>D</i> be its diameter. Denote by <i>d</i>(<i>G,k</i>) the number of pairs of vertices in <i>G</i> that are at d...

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