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92 Cahiers pour l'année 1997

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In the <i>Maximum Cardinality Bin Packing Problem</i>, we are given <i>m</i> bins of capacity <i>c</i> and <i>n</i> items of weights <i>w<sub>i</sub></i> (...

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Although airlines plan aircraft routes and crew schedules in advance, perturbations occur everyday. As a result, flight schedules may become infeasible and ...

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The search for optimal non-parametric estimates of the cumulative distribution and hazard functions under order constraints inspired at least two earlier cl...

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Let <i>G</i> be a multigraph containing no minor isomorphic to <i>K</i><sub>3,3</sub> or <i>K</i><sub>5</sub><i>e</i> (where <i>K</i><sub>5</sub><i>e</i> de...

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This paper presents a mixed 0-1 linear programming model for the metropolitan area network (MAN) expansion problem. The model includes the location of new...

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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 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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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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This paper considers the shortest path problem with waiting costs (SPWC) as an extension of the shortest path problem with time windows. The problem consis...

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We consider Nash equilibria as correlated equilibria and apply polyhedral theory to study extreme Nash equilibrium properties. We obtain an alternate proof ...

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The locomotive assignment problem is to provide at minimum cost sufficient motive power to pull all the trains of a time tabled schedule. Optimization metho...

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This paper addresses the problem of generating valid crew pairings in the context of a regional air carrier. The classical column generation solution appro...

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Systematic change of neighborhood within a possibly randomized local search algorithm yields a simple and effective metaheuristic for combinatorial and glo...

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An algorithm based upon the boundary-edges code and the reverse search method is proposed for enumerating non-isomorphic planar simply connected polyhexes. ...

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This article describes a heuristic and two exact algorithms for several classes of vehicle routing problems defined on tree networks. These include capacita...

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In recent years, several advances have been made towards the solution of stochastic vehicle routing problems (SVRPs). In particular, the Integer <i>L</i>-Sh...

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A decomposition method for global optimization, when some of the problem variables are integer, is presented. Potential solutions for a specific problem ar...

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This paper describes the Preferential Bidding Problem solved in the airline industry to construct personalized monthly schedules for pilots and officers. T...

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This paper describes an advanced bottom-up approach for modelling the energy-environment sector to study greenhouse gas abatement. Three new features are d...

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In this article we propose a model for the topological design problem of two-level multitechnology telecommunication networks that includes the optimal loca...

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

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This paper describes two variant of the Indian MARKAL model, a long-term technology oriented optimization model for energy-environment planning for India. T...

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This article considers a tool loading problem whose objective is to minimize the number of tool switches over time in order to process several parts on a fl...

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This paper introduces a strong valid inequality, the 2-path cut, to produce better lower bounds for the Vehicle Routing Problem with Time Windows (VRPTW). ...

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We propose a common solution approach for different crew scheduling problems arising at the planning and operational levels in the airline industry. Specifi...

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This article describes the results of a study aimed at improving linen delivery operations in a large teaching hospital in Montreal. Improvements over the p...

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We describe the analytic center cutting plane method and its relationship to classical methods of nondifferentiable optimization and column generation. Impl...

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The need for an integrating framework for vehicle routing and crew scheduling problems has been apparent for some time. While several attempts have been ma...

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Consider a set <i>L</i> of potential locations for <i>p</i> facilities and a set <i>U</i> of locations of given users. The <i>p</i>-median problem is to loc...

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Since the work of Zwart, it is known that cycling may occur in the cone splitting algorithm proposed by Tuy in 1964 to minimize a concave function over a po...

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The paper considers two cases of variational inequality problems. The first case involves an affine monotone operator over a convex set defined by a separat...

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Multi-commodity flow models are well known and have been widely used in the design of packet-switched networks. They have also been used as approximations ...

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Finding extremal graphs for expressions involving one or more invariants is viewed as a problem of combinatorial optimization. The recent Variable Neighborh...

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In the modeling of biological phenomena, in living organisms whether the measurements are of blood pressure, enzyme levels, biomechanical movements or heart...

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In this paper, we first study the problems of robust quadratic mean square stability and stabilization for a class of uncertain discrete-time linear systems...

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In this paper, we consider the problems of robust stability and control for the class of uncertain discrete-time linear systems with Frobenius norm-bounded ...

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Here we propose a general class of generalized linear models to describe time series of counts <i>Y</i><sub>1</sub>, ... ,<i>Y<sub>n</sub></i>. Following Ze...

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<i>Extensive facilities</i> are structures that are too large to be considered as single points. In the first part of this paper we propose integer program...

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Optimal control problems for linear stochastic continuous time systems are considered, where the time domain is decomposed into a finite set of <i>N</i> dis...

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We study the set of lower bounds which have been proposed for the numbering of a complete graph. We first show that the computation of most of them can be ...

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We present a general methodology to study the electricity market of a country or region, under various pricing mechanisms. The approach is based on modifica...

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We analyze the process of a two cut generation scheme in the analytic center cutting plane method. We propose an optimal restoration direction when the two...

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We present an algorithm for variational inequalities <i>VI</i>( <img src="G9756.gif" align=bottom>,<i>Y</i>) that is based on the Analytic Center Cutting Pl...

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This paper presents a sophisticated mixed integer linear programming model developed to help the regional decision makers in the long-term planning of the s...

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This paper presents a framework to assess a performability measure in a urban transportation network given the possibility of an accident condition. This fr...

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Good heuristic solutions for large Multisource Weber problems can be obtained by solving related <i>p</i>-median problems in which potential locations of th...

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The analytic center cutting plane (ACCPM) methods aims to solve nondifferentiable convex problems. The technique consists of building an increasingly refine...

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This article describes a lower bounding procedure and heuristics for the <i>Cycle Cover Problem</i> which consists of determining a least cost cover of an u...

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In this paper, we study the moments of cumulative processes. More specifically, we will evaluate explicitly the expectation of a product of <i>n</i> distinc...

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One of the main advantages of the discrete wavelet representation is the near-optimal estimation of signals corrupted with noise. After the seminal work of ...

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We propose a greedy heuristic and a Tabu Search type heuristic for channel block assignment subject to co-channel, adjacent channel, co-site constraints as ...

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We consider a managerial economics problem of controlling pollution caused by decentralised agents. We build a mathematical model for a local government ai...

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Cellular networks must be updated very often. Due to technical and economical reasons, the complete channel resetting of an urban network has to be done in...

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A combinatorial approach is used to derive asymptotic expressions for arbitrary moments of cumulative vector renewal reward processes, as the time horizon <...

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This paper introduces a new type of constraints, related to schedule synchronization, in the problem formulation of aircraft fleet assignment and routing pr...

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This paper contains some 80 annotated references on the vehicle routing problem. The titles are organized as follows: 1) the classical VRP with capacity an...

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Systematic change of neighborhood within a local search algorithm yields a simple and effective metaheuristic for combinatorial optimization. We present a ...

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In this paper we investigate the quadratic stability and quadratic stabilizability of the class of continuous-time linear systems with Markovian jumps and n...

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This paper classifies research contributions on decomposition approach for solving mathematical programming problems. More than 60 papers are presented with...

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An econometric model is developed and used to estimate price promotion effects on sales for the yogourt category in a Quebec market. More specifically, the...

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The purpose of this paper is to develop optimal tool partitioning policies and strip sequencing strategies for a class of flexible manufacturing problems. ...

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In this paper, we explore a weakness of a specific implementation of the analytic center cutting plane method applied to convex optimization problems, which...

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This paper presents a 0 - 1 column generation model with a resource constrained shortest path auxiliary problem for nurse scheduling. The master problem fin...

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G-97-01
Nesticity
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A hypergraph <i>H=(X,E)</i> is <i>nested</i> if its edges are pairwise disjoint or included one into the other. The <i>nesticity</i> of <i>H</i> is defined...

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The three-stage cutting stock problem consists in laying out a set of ordered rectangular pieces on some rectangular strips, and then these strips are laid ...

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In this paper we derive a law of the logarithm establishing the exact rate of uniform convergence for nearest neighbor kernel estimators of the density and ...

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In many medical experiments data are collected across time, over a number of similar trials or a number of experimental units. As is the case of neural spik...

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The long term analysis of an energy-environment system is fraught with various uncertainties. Classical stochastic programming has been used with large scal...

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We consider a weekly locomotive scheduling problem encountered at Swedish State Railways. The objective is to find cyclic locomotive schedules, which minim...

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Central limit theorems are obtained for the PARMSR (perturbation analysis Robbins-Monro single run) algorithm with averaging, updated either after every reg...

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The multisource Weber problem is to locate simultaneously <i>m</i> facilities in the Euclidean plane in order to minimize the total transportation cost for ...

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In recent years, there have been several important algorithmic developments for the traveling salesman problem and the vehicle routing problem. These inclu...

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We propose an improved version of the neighbor-joining algorithm (NJ) of Saitou and Nei (1987), which is one of the most popular distance methods to reconst...

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The utility of Bayes and empirical Bayes techniques is illustrated on an important problem often encountered in small area estimation. We propose various Ba...

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This paper deals with the production and the corrective maintenance planning control problem for failure prone manufacturing systems. The introduction of t...

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The capacitated multi-item lot sizing problem consists of finding a production schedule that minimizes over a finite number of periods the total production,...

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We consider the problem of inferring evolutionary trees. We propose a quartet reconstruction method which specifically produces trees whose edges have stron...

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This paper formulates the problem of maximal closure on a graph with resource constraints as an integer programming problem with binary variables, and propo...

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Future patterns of climate change and economic growth are critical parameters in long­term energy planning. This paper describes a multi­stage stochastic p...

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Given a set of entities, Cluster Analysis aims at finding subsets, called clusters, which are homogeneous and/or well separated. As many types of clusterin...

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The purpose of this document is to introduce the potential users to the new features of Extended MARKAL, stochastic programming and multiple region capabili...

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In this paper we will present UNJ, an unweighted version of the NJ algorithm (Saitou and Nei 1987; Studier and Keppler 1988). We will demonstrate that UNJ i...

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This paper describes the operational airline crew scheduling problem and represents a first published attempt to solve it. This problem consists of modifyin...

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This paper reports the use of an advanced Multi-region Bottom-up model, the Extended MARKAL, for an in-depth investigation of the responses by the Québec-On...

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Managing redundant information is becoming an important issue in today's increasingly large distributed computer networks. As total redundancy is extremely ...

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Convergence rate results are derived for a stochastic optimization problem where a performance measure is minimized with respect to a vector parameter <img ...

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Cet article présente une étude comparative des algorithmes de flot maximum pour la résolution du problème de fermeture maximale sur un graphe. Plusieurs ap...

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We study both the continuous and discrete problems of maximizing the product of two linear functions subject to all variables being between 0 and~1. We fir...

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La méthode de génération de colonnes est couramment utilisée pour résoudre des problèmes d'optimisation de grande taille. En pratique, on observe fréquemmen...

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The convergence and the complexity of a primal-dual column generation and cutting plane algorithm from approximate analytic centers for solving convex feasi...

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It is shown that the anytime deduction procedure for probabilistic entailment of Frisch and Haddawy does not have the correctness property when the probabil...

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