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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
171

Etude et résolution de problèmes d'ordonnancement d'opérations d'évacuation / Solving evacuation scheduling problem

Boukebab, Kaouthar 01 December 2015 (has links)
Les travaux présentés dans cette thèse, qui s’inscrivent dans le cadre du projet franco-allemand DSS_Evac_Logistic, visent à proposer des méthodes permettant de calculer des plans d’évacuation macroscopiques d’une ville lors d’une catastrophe majeure. Deux problèmes d’évacuations sont considérés dans cette thèse : le problème d’évacuation par bus et le problème d’évacuation par bus et voitures. Le problème d’évacuation par bus a pour objectif de définir un plan d’évacuation afin de mettre à l’abri les évacués. Dans cette thèse, nous nous sommes intéressés à l’étude de trois versions du problème d’évacuation par bus. La première version est monocritère où nous cherchons à minimiser la date de fin d’évacuation. Puis, dans le second problème et afin d’assurer la sécurité des évacués, nous avons considéré une version bicritère qui généralise le cas monocritère, en incluant le risque encouru lors de l’évacuation des personnes. Les deux critères à minimiser sont la date de fin d’évacuation et le risque. La troisième version est une version robuste bicritère qui permet d’appréhender l’incertitude sur les données. Le but est de minimiser à la fois la date de fin d’évacuation et les modifications apportées sur une solution, de sorte qu’elle soit réalisable pour n’importe quel scénario de données. Pour résoudre ces problèmes d’évacuation par bus, nous avons proposé des méthodes exactes et des méthodes heuristiques. / The work presented in this thesis, which is a part of the Franco-German project DSS_Evac_Logistic, aims at proposing methods to calculate macroscopic evacuation plans for mid-size towns after a tremendous disaster. Two evacuation problems have been tackled in this thesis : the bus evacuation problem and bus-and-vehicle evacuation problem. The bus evacuation problem aims at calculating an evacuation plan to relocate evacuees outside the endangered area. In this thesis, we consider three versions of the bus evacuation problem. The first one is a monocriterion problem, where the objective is to minimize the maximum evacuation time. In order to guarantee the safety of evacuees, we have considered a bicriteria problem, which is a generalization of the monocriterion version, in which we take into consideration the risk exposure of the evacuees. Consequently, the bicriteria problem is solved by minimizing the total evacuation time and the risk. The third version is a bicriteria robust version because most of the planning data is subject to uncertainty. The goal is to minimize both the evacuation time and the vulnerability of the schedule that is subject to different evacuation circumstances. To solve all the versions of the bus evacuation problem, we have developed exact solutions based on mathematical formulation to address small instances and heuristic solutions to deal with larger instances.
172

Análise de taxa média de bloqueio em conexões por algoritmos de caminhos mínimos: algoritmo de Yen e algoritmo genético / Average Analysis in blocking connections shortest paths algorithm: Yen algorithm and a genetic algorithm

Barreto, Tarcisio da Silva 15 December 2014 (has links)
Made available in DSpace on 2016-08-31T13:33:41Z (GMT). No. of bitstreams: 1 TarcisioSB_DISSERT.pdf: 1571314 bytes, checksum: 86e8646fa8da6455187767e219181490 (MD5) Previous issue date: 2014-12-15 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Studies on connections lock in computer networks have been gaining prominence in recent research focused on computational communication and technology. Several researchers have used various methods in order to identify and minimize the blocking rate that prevent a connection is established. This paper presents a blocking rate analysis in connections of shortest paths algorithms. They have on the performance of a transparent optical network. Two algorithms will be used to perform the analysis and simulations, the Genetic Algorithm (AG) and the algorithm Yen (AY). The Genetic Algorithm is based on Computational Intelligence (CI) and the Yen algorithm is based on the principle of finding and identifying the K shortest paths. Numerical simulations performed on different network scenarios show that the greater the number of connections, the higher the blocking rate in the connections. This study will help to identify which algorithm behaves better in the specific cases described in this work / Os estudos sobre bloqueio de conexões em redes de computadores vêm ganhando destaque em recentes pesquisas voltadas à comunicação computacional e tecnologia. Vários pesquisadores têm utilizado diversos métodos buscando identificar e minimizar ao máximo a taxa média de bloqueio que impedem que uma conexão seja estabelecida. Este trabalho apresenta uma análise de taxa média de bloqueio em conexões por algoritmos de caminhos mínimos. Têm sobre o desempenho de uma rede ótica transparente. Serão utilizados dois algoritmos para realizar a análise e as simulações, o Algoritmo Genético (AG) e o Algoritmo de Yen (AY). O Algoritmo Genético fundamentado por Inteligência Computacional (IC) e o Algoritmo de Yen baseado no princípio de encontrar e identificar os K menores caminhos. Simulações numéricas realizadas em diferentes cenários da rede mostram que, quanto maior o número de conexões, maior será a taxa média de bloqueio nas conexões. Através desse estudo será possível identificar qual algoritmo se comporta melhor para os casos específicos descritos nesse trabalho
173

O papel da distância em projetos topológicos de redes de distribuição elétrica / The role of distances in topological design of electrical distribution networks

Silva, Paulo Wagner Lopes da 20 May 2015 (has links)
This dissertation investigates in which conditions the optimal configuration of an electric power network is a minimum length spanning tree, and in which conditions it is shortest path tree configuration. For this purpose the dissertation, it applies computational optimization mathematical models of an optimal local access network design problem. The focus of the study is the 13.8 kV spacer cable primary radial networks. Applied models seek for the balance betweenfixedcostsandvariablecosts.Savedvaluesfromanoptimalnetworkcouldbeapplied to increase the range of the network and people reached as well. The bibliographic research is compound by three parts: graph theory, local access network optimization models, and distribution network costs. Research methodology includes the choice of the distribution system, determination of fixed and variable costs, choice and implementation of the local access network optimization models, tests in hypothetical and realistic systems by using the CPLEX solver, analysis of the resulting configuration, and construction of graphics to facilitate the results evaluation. It was found that the relationship between fixed costs and variable costs influences the optimal configuration of the distribution network in such a way that a low value of the quotient between fixed costs and variable costs contributes to a shortest path tree. On the other hand, a high quotient between fixed costs and variable costs contributes to a minimum length spanning tree configuration. However, others parameters must be considered to determine the network configuration such as extension, arches demand and quantity of arches. / O presente trabalho visa investigar sob quais condições a configuração ótima de uma rede de distribuição elétrica é uma árvore geradora mínima (AGM) e sob quais é uma árvore de caminhos mínimos (ACM). Utilizando, para isso, modelos matemáticos computacionais de otimização topológica de redes de utilidade pública. As redes de distribuição estudadas foram do tipo aérea radial primária protegida (ARPP) com nível de tensão em 13,8 kV. Os modelos utilizados prezam pelo equilíbrio entre o custo de investimento inicial (fixo) e os custos decorrentes da transferência de energia elétrica (variável). Os valores economizados através de uma configuração ótima da rede podem ser convertidos em investimentos para aumentar o número de pessoas com acesso aos recursos energéticos com eficiência e qualidade. A revisão bibliográfica foi dividida em três partes: teoria dos grafos, modelos de otimização de redes de acesso local e custos de redes de distribuição. A metodologia utilizada compreendeu as seguintes etapas: escolha do tipo de sistema de distribuição, determinação dos custos fixo e variável, escolha e implementação (GAMS) dos modelos, testes com exemplos de redes usando o solver CPLEX, análise das configurações resultantes e elaboração de gráficos para facilitar a avaliação dos resultados. Os resultados mostraram que a relação entre o custo fixo β e o custo variável γ exerce influência determinante na configuração ótima de uma rede de distribuição ARPP. Um valor baixo de β/γ, favorece a ACM. Já valores elevados de β/γ, conduzem a solução para uma AGM. No entanto, essa relação não é o único fator que determina a configuração da rede, outros parâmetros como extensão, demanda dos nós e quantidade de possíveis arcos influenciam de forma significativa na solução apresentada.
174

Shared Mobility Optimization in Large Scale Transportation Networks: Methodology and Applications

January 2018 (has links)
abstract: Optimization of on-demand transportation systems and ride-sharing services involves solving a class of complex vehicle routing problems with pickup and delivery with time windows (VRPPDTW). Previous research has made a number of important contributions to the challenging pickup and delivery problem along different formulation or solution approaches. However, there are a number of modeling and algorithmic challenges for a large-scale deployment of a vehicle routing and scheduling algorithm, especially for regional networks with various road capacity and traffic delay constraints on freeway bottlenecks and signal timing on urban streets. The main thrust of this research is constructing hyper-networks to implicitly impose complicated constraints of a vehicle routing problem (VRP) into the model within the network construction. This research introduces a new methodology based on hyper-networks to solve the very important vehicle routing problem for the case of generic ride-sharing problem. Then, the idea of hyper-networks is applied for (1) solving the pickup and delivery problem with synchronized transfers, (2) computing resource hyper-prisms for sustainable transportation planning in the field of time-geography, and (3) providing an integrated framework that fully captures the interactions between supply and demand dimensions of travel to model the implications of advanced technologies and mobility services on traveler behavior. / Dissertation/Thesis / Doctoral Dissertation Civil, Environmental and Sustainable Engineering 2018
175

Uma col?nia de formigas para o caminho mais curto multiobjetivo

Bezerra, Leonardo Cesar Teon?cio 07 February 2011 (has links)
Made available in DSpace on 2015-03-03T15:47:46Z (GMT). No. of bitstreams: 1 LeonardoCTB_DISSERT.pdf: 2119704 bytes, checksum: 5bdd21de8bfa668bba821593cdd5289f (MD5) Previous issue date: 2011-02-07 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / Multi-objective combinatorial optimization problems have peculiar characteristics that require optimization methods to adapt for this context. Since many of these problems are NP-Hard, the use of metaheuristics has grown over the last years. Particularly, many different approaches using Ant Colony Optimization (ACO) have been proposed. In this work, an ACO is proposed for the Multi-objective Shortest Path Problem, and is compared to two other optimizers found in the literature. A set of 18 instances from two distinct types of graphs are used, as well as a specific multiobjective performance assessment methodology. Initial experiments showed that the proposed algorithm is able to generate better approximation sets than the other optimizers for all instances. In the second part of this work, an experimental analysis is conducted, using several different multiobjective ACO proposals recently published and the same instances used in the first part. Results show each type of instance benefits a particular type of instance benefits a particular algorithmic approach. A new metaphor for the development of multiobjective ACOs is, then, proposed. Usually, ants share the same characteristics and only few works address multi-species approaches. This works proposes an approach where multi-species ants compete for food resources. Each specie has its own search strategy and different species do not access pheromone information of each other. As in nature, the successful ant populations are allowed to grow, whereas unsuccessful ones shrink. The approach introduced here shows to be able to inherit the behavior of strategies that are successful for different types of problems. Results of computational experiments are reported and show that the proposed approach is able to produce significantly better approximation sets than other methods / Problemas de otimiza??o combinat?ria multiobjetivo apresentam caracter?sticas peculiares que exigem que t?cnicas de otimiza??o se adaptem a esse contexto. Como muitos desses problemas s?o NP-?rduos, o uso de metaheur?sticas tem crescido nos ?ltimos anos. Particularmente, muitas abordagens que utilizam a Otimiza??o por Col?nias de Formigas t?m sido propostas. Neste trabalho, prop?e-se um algoritmo baseado em col?nias de formigas para o Problema do Caminho mais Curto Multiobjetivo, e compara-se o algoritmo proposto com dois otimizadores encontrados na literatura. Um conjunto de 18 inst?ncias oriundas de dois tipos de grafos ? utilizado, al?m de uma metodologia espec?fica para a avalia??o de otimizadores multiobjetivo. Os experimentos iniciais mostram que o algoritmo proposto consegue gerar conjuntos de aproxima??o melhores que os demais otimizadores para todas as inst?ncias. Na segunda parte do trabalho, uma an?lise experimental de diferentes abordagens publicadas para col?nias de formigas multiobjetivo ? realizada, usando as mesmas inst?ncias. Os experimentos mostram que cada tipo de inst?ncia privilegia uma abordagem algor?tmica diferente. Uma nova met?fora para o desenvolvimento deste tipo de metaheur?stica ? ent?o proposta. Geralmente, formigas possuem caracter?sticas comuns e poucos artigos abordam o uso de m?ltiplas esp?cies. Neste trabalho, uma abordagem com m?ltiplas esp?cies competindo por fontes de comida ? proposta. Cada esp?cie possui sua pr?pria estrat?gia de busca e diferentes esp?cies n?o tem acesso ? informa??o dada pelo ferom?nio das outras. Como na natureza, as popula??es de formigas bem sucedidas tem a chance de crescer, enquanto as demais se reduzem. A abordagem apresentada aqui mostra-se capaz de herdar o comportamento de estrat?gias bem-sucedidas em diferentes tipos de inst?ncias. Resultados de experimentos computacionais s?o relatados e mostram que a abordagem proposta produz conjuntos de aproxima??o significativamente melhores que os outros m?todos
176

Estudo do acoplamento elétrico-energético no planejamento da operação de curto-curtíssimo prazo utilizando FPOCA / The study of electric-energetic coupling in the short-shortest term operation planning using FPOCA

Luiz Giovani Lopes Rodrigues 15 December 2003 (has links)
Este trabalho traz um estudo inicial do acoplamento elétrico-energético no planejamento da operação de curto-curtíssimo prazo utilizando Fluxo de Potência Ótimo em Corrente Alternada (FPOCA) com o objetivo de averiguar possíveis desvios entre o planejamento energético e o planejamento elétrico. É feita uma análise da influência dos aspectos elétricos do sistema de transmissão no planejamento energético de curto prazo utilizando-se um FPOCA, juntamente com a minimização do custo da geração e das perdas na transmissão. A minimização do custo da geração é feita através de uma otimização do sistema hidrotérmico utilizando-se um Programa de Otimização de Sistema Hidrotérmico (POSH) baseado em um algoritmo simplex convexo e na aplicação da teoria de fluxo em rede, enquanto que a minimização das perdas na transmissão é feita utilizando-se um FPOCA baseado no método Dual-Newton. Estas ferramentas permitem analisar a necessidade de ajustes para compatibilizar a otimização energética e a otimização elétrica de um sistema eletroenergético, e buscar um planejamento \"ótimo\" que atenda os planejamentos energético e elétrico. Dessa forma, a interface elétrico-energética se torna mais \"forte\", pois as metas de geração obtidas pelo planejamento de curto prazo que serão passadas para o planejamento de curtíssimo prazo, já incluem o efeito dos aspectos elétricos do sistema. Isto proporciona um controle dos desvios da trajetória \"ótima\" do sistema, o que contribui para melhorar a otimização global do planejamento da operação eletroenergética. / This work brings a beginning study of the electric-energetic coupling in the short-shortest term operation planning using Optimal Power Flow in Alternate Current (OPFAC) aiming to inquire possible mismatches between the energetic planning and the eletric planning. It is made an analysis of the electrical aspects influence in the short term energetic planning using OPFAC together with the minimization of generation cost and the transmission losses. The generation cost minimization is made for the hidrothermal system optimization using a Hydrothermal System Optimization Program (POSH) based on a convex simplex algorithm and the application of the network flow theory, while the transmission losses minimization is made using an OPFAC based on the Dual-Newton method. These tools allow to analyze the necessity of adjustments to make compatible the energetic optimization and the electric optimization of the power system, and to search an \"optimal\" planning that attends both the energetic planning and electric planning. Like this, the electric-energetic interface becomes strongest, therefore the generation goals gotten by the short-term planning, that will be passed to the shortest-term planning, already includes the effect of the electric system aspects. These one provide the mismatches control in the optimal trajectory of the system and it contributes to improve the global optimization of power system operation planning. The analyzed system is the 440 kV Equivalent System of CESP (Energetic Company of São Paulo), with 53 bus, being 7 generation bus, 85 transmission lines and 48 transformers.
177

Qualidade de serviço em rede IP utilizando logica fuzzy / Quality of service in IP network using fuzzy logic

Resende, Raulison Alves, 1970- 31 July 2006 (has links)
Orientador: Akebo Yamakami / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-06T20:32:53Z (GMT). No. of bitstreams: 1 Resende_RaulisonAlves_D.pdf: 558127 bytes, checksum: 8c65274e70573045a52e4b1101a2c32e (MD5) Previous issue date: 2006 / Resumo: A teoria de conjuntos fuzzy provê um ferramental para desenvolver processos aproximados de raciocínio quando a informação disponível é incerta, incompleta, imprecisa ou vaga. Com as novas ferramentas emergentes na área de inteligência computacional, tais como lógicas não padronizadas, redes neurais e raciocínio simbólico, esta nova teoria é um acréscimo bem-vindo ao repertório de ferramentas tradicionais apropriadas. Neste sentido, esta tese propõe três estratégias para o provimento de qualidade de serviço em redes IP, usando lógica fuzzy. Como primeira proposta é implementado um módulo inteligente para gerenciamento da QoS por meio da criação de políticas para roteadores do tipo DiffServ. A segunda estratégia consiste em um algoritmo fuzzy que resolve o problema de roteamento baseado em restrição de tempo com mínimo custo. Esta proposta apresentou resultados satisfatórios quando comparada com a solução sem lógica fuzzy. E, por último, se propõe um controlador de admissão de conexão para tratar as informações com certo grau de incertezas em redes IP com MPLS. O controlador apresenta as seguintes vantagens: flexibilização da admissão de conexão e possibilidade de incluir mais informações da rede e do tráfego na tomada da decisão sem aumentar consideravelmente a complexidade do controlador / Abstract: Fuzzy set theory provides a machinery for carrying out approximate reasoning processes when available information is uncertain, incomplete, imprecise, or vague. With the emergence of new tools in the area of computational intelligence, such as non standard logics, neural networks, and symbolic reasoning, this new theory is a welcome addition to the repertoire of traditional appropriate tools. In this sense, this thesis proposes three different strategies to apply Fuzzy Logic to provide QoS in IP Networks. The first one is the implementation of an intelligent, policy-based module for QoS management. The module permits the creation of policies to configure QoS in routers and a practical implementation has been performed for a DiffServ router. The second strategy proposes a fuzzy algorithm to solve the problem of routing based on time restrictions with minimum costs. The results obtained from this algorithm were satisfactory when compared to similar solutions that did not involve fuzzy logic. Finally, the third strategy proposes a Connection Admission Controller to process information that contains a high level of uncertainty in IP networks over MPLS. The controller offers the following advantages: flexibility for connections admission and the possibility of including more network and traffic information in the decision making process without considerably increasing the controller complexity / Doutorado / Telecomunicações e Telemática / Doutor em Engenharia Elétrica
178

Zona de empate : o elo entre transformadas de watershed e conexidade nebulosa / Tie-zone : the bridge between watershed transforms and fuzzy connectedness

Audigier, Romaric Matthias Michel 13 August 2018 (has links)
Orientador: Roberto de Alencar Lotufo / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-13T08:32:02Z (GMT). No. of bitstreams: 1 Audigier_RomaricMatthiasMichel_D.pdf: 1753584 bytes, checksum: 1d31eb6f095099ffb5c3ec8d0a96a9cf (MD5) Previous issue date: 2007 / Resumo: Esta tese introduz o novo conceito de transformada de zona de empate que unifica as múltiplas soluções de uma transformada de watershed, conservando apenas as partes comuns em todas estas, tal que as partes que diferem constituem a zona de empate. A zona de empate aplicada ao watershed via transformada imagem-floresta (TZ-IFT-WT) se revela um elo inédito entre transformadas de watershed baseadas em paradigmas muito diferentes: gota d'água, inundação, caminhos ótimos e floresta de peso mínimo. Para todos esses paradigmas e os algoritmos derivados, é um desafio se ter uma solução única, fina, e que seja consistente com uma definição. Por isso, propõe-se um afinamento da zona de empate, único e consistente. Além disso, demonstra-se que a TZ-IFT-WT também é o dual de métodos de segmentação baseados em conexidade nebulosa. Assim, a ponte criada entre as abordagens morfológica e nebulosa permite aproveitar avanços de ambas. Em conseqüência disso, o conceito de núcleo de robustez para as sementes é explorado no caso do watershed. / Abstract: This thesis introduces the new concept of tie-zone transform that unifies the multiple solutions of a watershed transform, by conserving only the common parts among them such that the differing parts constitute the tie zone. The tie zone applied to the watershed via image-foresting transform (TZ-IFTWT) proves to be a link between watershed transforms based on very different paradigms: drop of water, flooding, optimal paths and forest of minimum weight. For all these paradigms and the derived algorithms, it is a challenge to get a unique and thin solution which is consistent with a definition. That is why we propose a unique and consistent thinning of the tie zone. In addition, we demonstrate that the TZ-IFT-WT is also the dual of segmentation methods based on fuzzy connectedness. Thus, the bridge between the morphological and the fuzzy approaches allows to take benefit from the advance of both. As a consequence, the concept of cores of robustness for the seeds is exploited in the case of watersheds. / Doutorado / Engenharia de Computação / Doutor em Engenharia Elétrica
179

Robustness and preferences in combinatorial optimization

Hites, Romina 15 December 2005 (has links)
In this thesis, we study robust combinatorial problems with interval data. We introduce several new measures of robustness in response to the drawbacks of existing measures of robustness. The idea of these new measures is to ensure that the solutions are satisfactory for the decision maker in all scenarios, including the worst case scenario. Therefore, we have introduced a threshold over the worst case costs, in which above this threshold, solutions are no longer satisfactory for the decision maker. It is, however, important to consider other criteria than just the worst case.<p>Therefore, in each of these new measures, a second criteria is used to evaluate the performance of the solution in other scenarios such as the best case one. <p><p>We also study the robust deviation p-elements problem. In fact, we study when this solution is equal to the optimal solution in the scenario where the cost of each element is the midpoint of its corresponding interval. <p><p>Then, we finally formulate the robust combinatorial problem with interval data as a bicriteria problem. We also integrate the decision maker's preferences over certain types of solutions into the model. We propose a method that uses these preferences to find the set of solutions that are never preferred by any other solution. We call this set the final set. <p><p>We study the properties of the final sets from a coherence point of view and from a robust point of view. From a coherence point of view, we study necessary and sufficient conditions for the final set to be monotonic, for the corresponding preferences to be without cycles, and for the set to be stable.<p>Those that do not satisfy these properties are eliminated since we believe these properties to be essential. We also study other properties such as the transitivity of the preference and indifference relations and more. We note that many of our final sets are included in one another and some are even intersections of other final sets. From a robust point of view, we compare our final sets with different measures of robustness and with the first- and second-degree stochastic dominance. We show which sets contain all of these solutions and which only contain these types of solutions. Therefore, when the decision maker chooses his preferences to find the final set, he knows what types of solutions may or may not be in the set.<p><p>Lastly, we implement this method and apply it to the Robust Shortest Path Problem. We look at how this method performs using different types of randomly generated instances. <p> / Doctorat en sciences, Orientation recherche opérationnelle / info:eu-repo/semantics/nonPublished
180

Quelques Algorithmes pour des problèmes de plus court chemin et d'opérations aériennes / Algorithms for shortest path and airline problems

Parmentier, Axel 10 November 2016 (has links)
Cette thèse développe des algorithmes pour les problèmes de plus court chemin sous cont-rain-tes de ressources, et les applique à l'optimisation des rotations des avions et des équipages d'une compagnie aérienne dans le cadre d'approches par génération de colonnes.Les problèmes de plus court chemin sous contraintes de ressources sont généralement résolus grâce à une énumération intelligente de tous les chemins non dominés. Les approches récentes utilisent des bornes sur les ressources des chemins pour éliminer des solutions partielles. L'efficacité de la méthode est conditionnée par la qualité des bornes utilisées. Notre principale contribution au domaine est l'introduction d'une procédure générique pour calculer des bornes qui s'applique à la plupart des problèmes de chemins sous contraintes, et en particulier les problèmes stochastiques. A cette fin, nous introduisons une généralisation du problème de plus court chemin sous contraintes dans laquelle les ressources des chemins appartiennent à un monoïde ordonné comme un treillis. La ressource d'un chemin est la somme des ressources de ses arcs, le terme somme désignant l'opérateur du monoïde. Le problème consiste à trouver parmi les chemins qui satisfont une contrainte donnée celui dont la ressource minimise une fonction de coût croissante de la ressource des chemins. Nous généralisons les algorithmes d'énumération à ce nouveau problème. La théorie des treillis nous permet de construire une procédure polynomiale pour trouver des bornes de qualité. L'efficacité pratique de la méthode est évaluée au travers d'une étude numérique détaillée sur des problèmes de chemins déterministes et stochastiques. Les procédures de calcul des bornes peuvent être interprétées comme des généralisations aux monoïdes ordonnés comme des treillis d'algorithmes de la littérature définis pour résoudre un problème de chemin pour lequel les ressources des chemins prennent leur valeur dans un semi-anneau.Nos algorithmes de chemins ont été appliqués avec succès au problème de crew pairing. Étant donné un ensemble de vols opérés par une compagnie aérienne, les problèmes d'aircraft routing et de crew pairing construisent respectivement les séquences de vols opérées par les avions et par les équipages de manière à couvrir tous les vols à moindre coût. Comme certaines séquences de vols ne peuvent être réalisées par un équipage que s'il reste dans le même avion, les deux problèmes sont liés. La pratique actuelle dans l'industrie aéronautique est de résoudre tout d'abord le problème d'aircraft routing, puis le problème de crew pairing, ce qui aboutit à une solution non-optimale. Des méthodes de résolution pour le problème intégré ont été développées ces dix dernières années. Nous proposons une méthode de résolution pour le problème intégré reposant sur deux nouveaux ingrédients : un programme linéaire en nombre entier compact pour le problème d'aircraft routing, ainsi que de nouveaux pour le problème esclave de l'approche usuelle par génération de colonnes du problème de crew pairing. Ces algorithmes pour le problème esclave sont une application de nos algorithmes pour le problème de plus court chemin sous contraintes. Nous généralisons ensuite cette approche de manière à prendre en compte des contraintes de probabilités sur la propagation du retard. Ces algorithmes permettent de résoudre quasiment à l'optimum les instances industrielles d'Air France / This thesis develops algorithms for resource constrained shortest path problems, and uses them to solve the pricing subproblems of column generation approaches to some airline operations problems.Resource constrained shortest path problems are usually solved using a smart enumeration of the non-dominated paths. Recent improvements of these enumeration algorithms rely on the use of bounds on path resources to discard partial solutions. The quality of the bounds determines the performance of the algorithm. Our main contribution to the topic is to introduce a standard procedure to generate bounds on paths resources in a general setting which covers most resource constrained shortest path problems, among which stochastic versions. In that purpose, we introduce a generalization of the resource constrained shortest path problem where the resources are taken in a lattice ordered monoid. The resource of a path is the monoid sum of the resources of its arcs. The problem consists in finding a path whose resource minimizes a non-decreasing cost function of the path resource among the paths that satisfy a given constraint. Enumeration algorithms are generalized to this framework. We use lattice theory to provide polynomial procedures to find good quality bounds. The efficiency of the approach is proved through an extensive numerical study on deterministic and stochastic path problems. Interestingly, the bounding procedures can be seen as generalizations to lattice ordered monoids of some algebraic path problem algorithms which initially work with resources in a semiring.Given a set of flight legs operated by an airline, the aircraft routing and the crew pairing problem build respectively the sequences of flight legs operated by airplanes and crews at minimum cost. As some sequences of flight legs can be operated by crews only if they stay in the same aircraft, the two problems are linked. The current practice in the industry is to solve first the aircraft routing, and then the crew pairing problem, leading to a non-optimal solution. During the last decade, solution schemes for the integrated problem have been developed. We propose a solution scheme for the integrated problem based on two new ingredients: a compact integer program approach to the aircraft routing problem, and a new algorithm for the pricing subproblem of the usual column generation approach to the crew pairing problem, which is based on our resource constrained shortest path framework. We then generalize the algorithm to take into account delay propagation through probabilistic constraints. The algorithms enable to solve to near optimality Air France industrial instances

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