O objetivo desta dissertação é avaliar o desempenho de ambientes virtuais de roteamento construídos sobre máquinas x86 e dispositivos de rede existentes na Internet atual. Entre as plataformas de virtualização mais utilizadas, deseja-se identificar quem melhor atende aos requisitos de um ambiente virtual de roteamento para permitir a programação do núcleo de redes de produção. As plataformas de virtualização Xen e KVM foram instaladas em servidores x86 modernos de grande capacidade, e comparadas quanto a eficiência, flexibilidade e capacidade de isolamento entre as redes, que são os requisitos para o bom desempenho de uma rede virtual. Os resultados obtidos nos testes mostram que, apesar de ser uma plataforma de virtualização completa, o KVM possui desempenho melhor que o do Xen no encaminhamento e roteamento de pacotes, quando o VIRTIO é utilizado. Além disso, apenas o Xen apresentou problemas de isolamento entre redes virtuais. Também avaliamos o efeito da arquitetura NUMA, muito comum em servidores x86 modernos, sobre o desempenho das VMs quando muita memória e núcleos de processamento são alocados nelas. A análise dos resultados mostra que o desempenho das operações de Entrada e Saída (E/S) de rede pode ser comprometido, caso as quantidades de memória e CPU virtuais alocadas para a VM não respeitem o tamanho dos nós NUMA existentes no hardware. Por último, estudamos o OpenFlow. Ele permite que redes sejam segmentadas em roteadores, comutadores e em máquinas x86 para que ambientes virtuais de roteamento com lógicas de encaminhamento diferentes possam ser criados. Verificamos que ao ser instalado com o Xen e com o KVM, ele possibilita a migração de redes virtuais entre diferentes nós físicos, sem que ocorram interrupções nos fluxos de dados, além de permitir que o desempenho do encaminhamento de pacotes nas redes virtuais criadas seja aumentado. Assim, foi possível programar o núcleo da rede para implementar alternativas ao protocolo IP. / The aim of this work is to evaluate the performance of routing virtual environments built on x86 machines and network devices existing on the Internet today. Among the most widely used virtualization platforms, we want to identify which best meets the requirements of a virtual routing to allow programming of the core production networks. Virtualization platforms Xen and KVM were installed on modern large capacity x86 machines, and they were compared for efficiency, flexibility and isolation between networks, which are the requirements for good performance of a virtual network. The tests results show that, despite being a full virtualization platform, KVM has better performance than Xen in forwarding and routing packets when the VIRTIO is used. Furthermore, only Xen had isolation problems between networks. We also evaluate the effect of the NUMA architecture, very common in modern x86 servers, on the performance of VMs when lots of memory and processor cores are allocated to them. The results show that Input and Output (I/O) network performance can be compromised whether the amounts of virtual memory and CPU allocated to VM do not respect the size of the existing hardware NUMA nodes. Finally, we study the OpenFlow. It allows slicing networks into routers, switches and x86 machines to create virtual environments with different routing forwarding rules. We found that, when installed with Xen and KVM, it enables the migration of virtual networks among different physical nodes, without interruptions in the data streams, and allows to increase the performance of packet forwarding in the virtual networks created. Thus, it was possible to program the core network to implement alternatives to IP protocol.

The main aim of the present dissertation has been the proposition and the following verification of tourist routes of the Kožlany region, so that they would comply with the pedagogic/recreational needs of first grade pupils. The routes are also eligible for pupils of higher grades, without losing value or meaning. I have chosen the Kožlany region for the vast majority of the tourist routes because of its unusual and picturesque scenery with slight terrain elevation and unpredictable landscape changes, thus being a surprisingly refreshing and interesting region to travel through. Besides differentiated terrain Kožlany is a region with a large wood covered area of remarkable beauty and historical monuments which are rarely mentioned yet deliver an unforgettable experience of history and greatness. Among the most important edifices are the monasteries of Plasy and Marianská Tynice. Although other monuments have lesser historical importance than the mentioned monasteries, they do not fail to captivate with their uniqueness and splendor. Examples of such monuments and historical sites are the ruined fortresses of Krašov and Krakovec, the hunting chateau Angerbach, the Jewish cemetery in Kožlany and others. The town of Kožlany is a small, but on the other hand a very interesting place. Two important historical figures are linked with the town, concretely the Czech king Vaclav I. and the second President of the Czechoslovak Republic, Dr. Edward Beneš. Both personalities are mentioned in the dissertation in concordance with their relevance to the tourist routes. The routes have been conceived for hiking, some of them also for cycling tourism, taking in account the amazing nature around Kožlany. The dissertation further includes a theoretical part which concentrates on the content, forms and especially on the importance of tourism in education. It also deals with the representation of tourism related activities in the instructional basis for the first grade development programs for primary, general and national schools. Each of the designed routes is thoroughly characterized according to its length, difficulty, duration, initial point, target point and the attractiveness of spots which should not be missed on the way. A detailed description of each journey's course with maps and additional photographic materials is to be found in the dissertation. Legends or fairy-tales are included in the case of some routes to make them more pleasant and meaningful for the travelling children, eventually adults. Every route has a specific name to keep a clear overview of all the routes as well as to motivate the possible travellers. The dissertation provides a wide range of materials and facts that will help the teacher orientate in the concrete journey and pass new knowledge to his pupils. A variety of games that could be relevantly played in the course of the journey are offered as well.\\

Made available in DSpace on 2014-07-29T14:57:52Z (GMT). No. of bitstreams: 1 Dissertacao Diego Galindo Pecin.pdf: 448272 bytes, checksum: 755b351108c1082bc3bdb084b7add6ec (MD5) Previous issue date: 2010-02-23 / This dissertation addresses the optimization of the Elementary Shortest Path Problem with a Capacity Constraint (ESPPCC) and describes algorithms for its resolution that make use of concepts such as Label-Setting, Bidirectional Dynamic Programming and Decremental State Space Relaxation. These algorithms were used in a robust CVRP s Branch-and- Cut-and-Price framework as the column generation mechanism. The resulting BCP was used to obtain results (lower bounds, processing time and the number of branching nodes generated) to several CVRP s test instances. These results are compared with previous ones obtained with the original BCP, which is based on k-cycle elimination. Elementary routes are also explored in a route enumeration context, which allows the enumeration of all possible relevant elementary routes, i.e., all routes that have a chance of being part of an optimal CVRP s solution. If the number of relevant routes is not too large (say, in the range of tenths of thousands), the overall problem may be solved by feeding a general MIP solver with a set-partition formulation containing only those routes. If this set-partition can be solved, the optimal solution will be found and no branch will be necessary. Sometimes this leads to very significant speedups when compared to traditional branch strategies. / Esta dissertação aborda o Problema do Caminho Elementar Mínimo com Restrição de Capacidade (ESPPCC Elementary Shortest Path Problem with a Capacity Constraint) e descreve algoritmos para a sua resolução que fazem uso de conceitos tais como Correção de Rótulos, Programação Dinâmica Bidirecional e Relaxação Decrescente do Espaço de Estados. Esses algoritmos foram usados como geradores de rotas elementares no subproblema de geração de colunas de um algoritmo BCP robusto para o CVRP. Os resultados (limites inferiores, tempo de processamento e número de nós gerados) obtidos, para algumas instâncias de teste do CVRP, são comparados aos obtidos na versão original desse algoritmo BCP, que utiliza rotas não elementares sem 3-ciclos ou 4-ciclos. Rotas elementares também são exploradas em um contexto de enumeração para o CVRP, a qual permite obter rotas (usando um critério baseado em limites e em custo reduzido) que possuem uma chance de pertencer a uma solução ótima. Se o número de rotas não for muito grande (na ordem de poucos de milhares), então todo o problema pode ser resolvido como um problema de particionamento de conjuntos contendo apenas tais rotas. Algumas vezes isso acelera o algoritmo Branch-and-Bound consideravelmente, quando comparado com estratégias tradicionais de particionamento (branching), já que muitos nós da árvore podem ser resolvidos sem a geração de novos nós.

A Lei nº 12.587, de 3 de janeiro de 2012, obriga a todos os municípios brasileiros com população superior a 20 mil habitantes a elaborarem um plano de mobilidade urbana integrado e compatível com seus respectivos planos diretores ou neles inseridos, priorizando os modos de transporte não motorizados. Apesar da exigência legal, muitos municípios brasileiros, principalmente os de pequeno porte, não dispõem de diretrizes para o desenvolvimento de sistemas cicloviários. O objetivo deste trabalho é elaborar um método para definição de rede de rotas cicláveis em áreas urbanas de cidades de pequeno porte, cuja ideia central é avaliar segmentos viários com relação a fatores que influenciam no uso da bicicleta como modo de transporte urbano, tais como declividade, disponibilidade de espaço e influência exercida pelos veículos motorizados. O método proposto é subdividido em cinco etapas: (1) caracterização da área de estudo; (2) análise dos polos geradores de tráfego por bicicletas; (3) avaliação da compatibilidade das vias com o transporte cicloviário; (4) identificação das rotas cicláveis; e (5) definição da rede. Os modelos escolhidos para a verificação do perfil topográfico e para a avaliação da qualidade de serviço das vias de tráfego para o transporte cicloviário são, respectivamente, o modelo da AASHTO (1999) e o modelo de Sorton e Walsh (1994). Foi realizado um estudo de caso na cidade de Bariri-SP. Os resultados mostram que as rotas cicláveis identificadas priorizam segmentos com infraestrutura cicloviária pré-existente, assim como locais que necessitam de facilidades para ciclistas, como ciclofaixas e ciclovias, e dispõem de espaço para sua inserção. Quanto aos espaços compartilhados, nota-se uma tendência de que as rotas cicláveis sejam compostas por segmentos com boas avaliações globais de nível de estresse. A rede de rotas cicláveis definida para a cidade de Bariri-SP é formada por 19 eixos viários distribuídos de maneira a atender toda a área delimitada para estudo. / The law 12.587 of January 3rd, 2012, enforces every Brazilian city over 20,000 inhabitants to elaborate an urban mobility plan integrated and compatible with their respective master plans, giving priority to non-motorized transportation modes. Despite legal enforcement, many Brazilian cities, mainly the small ones, are not given proper guidelines to develop cycling systems. This research\'s goal is to elaborate a method to define a cycling routes network in urban areas of small-sized cities, whose main point is to assess road segments according to factors that influence the bicycle use as an urban transportation mode, such as slope, space availability to stand cycling transportation as well as motorized vehicles influence on bicycle traffic. The proposed method splits into five steps: (1) study area characterization; (2) analysis of bicycle traffic generator poles; (3) evaluation of the streets compatibility with bicycle transportation; (4) cycling routes identification; (5) network definition. The chosen models for topographic verification and service quality ratings of the roads for cycling transportation are, respectively, the AASHTO\'s (1999) model and the Sorton and Walsh\'s (1994) model. A case study was carried out in the city of Bariri-SP. The results of the proposed method\'s application show that the identified cycling routes prioritize road segments with cycling infrastructure already existent, as well as places in need of cycling facilities, such as cycle lanes and cycle paths, that have available space to accommodate them. Concerning shared spaces, there\'s a trend that cycling routes are composed of segments with good global stress level evaluations. The cycling routes network defined in the city of Bariri-SP is made up by 19 road axes widespread to serve the whole area delimited for study.

Desde a descoberta do herpes vírus humano tipo 8 (HHV-8) como o agente etiológico do sarcoma de Kaposi (SK) nas suas diferentes formas clínico-epidemiológicas, vários estudos vêm sendo conduzidos com o intuito de determinar as vias de transmissão desse vírus em populações endêmicas e de risco epidemiológico. Em regiões endêmicas, a transmissão viral foi relacionada à transmissão horizontal de mães para filhos e entre irmãos e a sexual principalmente, nos casos de SK/aids. Com o objetivo de determinar segmentos do genoma viral em fluídos biológicos e consequentemente seu potencial infectante foi conduzido o presente trabalho. Foram avaliados quanto à presença de segmentos localizados em posições estratégicas do genoma do HHV-8 em sangue, saliva e urina de 76 pacientes com SK/aids, 19 pacientes com HIV/aids, 4 casos de SK clássico e 11 indivíduos sadios (HIV-soronegativos, sem SK). Foram utilizadas as técnicas de PCR "nested" para as ORF K1, ORF 25, ORF 26, ORF K8.1 e ORF 73 em DNA extraído de material de biópsia de lesão de SK (controle positivo), células do sangue periférico, saliva e urina. Os resultados de PCR positivo para o HHV-8 foram analisados quanto a variáveis epidemiológicas, clínicas e laboratoriais. Foram consideradas como variáveis: sexo, cor, origem étnica, tempo de infecção por HIV e de acompanhamento do SK, terapia ARV e para SK, contagem de células CD4+ e sorologia para o HHV-8 (IFI-LANA e IFI-Lítico). Os testes estatísticos de regressão logística e de razão de chances foram usados para detectar as associações estatisticamente significantes entre as PCRs positivas e as variáveis estudadas nos grupos SK/aids e HIV/aids. Os subtipos do HHV-8 foram também determinados pela técnica de PCR-RFLP da ORF K1 (VR1). Os resultados obtidos mostraram a detecção de DNA/HHV-8 em 80,2% do material de biópsia, 69,7% no sangue, 59,2% na saliva e 21,0% na urina de pacientes com SK/aids. No grupo HIV/aids, a PCR para o HHV-8 resultou positiva em 47,4% dos casos no sangue e em 26,3% na saliva e urina. Já no grupo SK clássico 100% das biópsias e salivas resultaram PCR positiva, 67% do sangue e 33% das urinas. A avaliação sorológica revelou 73,3% de reatividade para IFI-LANA e 85,3% para a IFI-Lítico no grupo SK/aids, enquanto o grupo HIV/aids mostrou reatividade de 15,8% para IFI-LANA e 47,4% para IFI-Lítico; todos os pacientes apresentaram resultados reagentes nas duas sorologias para o HHV-8 no grupo de SK clássico. No grupo controle sadio não houve reatividade na sorologia para o HHV-8, com exceção de um caso, que mostrou ser reagente na IFI-LANA. Foi possível realizar a subtipagem do HHV-8 em amostras de 69 pacientes, sendo detectadas 27 cepas do subtipo A, 13 do subtipo B, 28 do subtipo C e 1 do subtipo E. Após as análises estatísticas foi verificado que as PCRs que identificam as regiões ORF 26, ORF K8.1 e ORF 73 foram as que apresentaram melhor desempenho na identificação de DNA/HHV-8. Houve associação entre a reatividade de IFI-Lítico e a presença do vírus no sangue periférico, assim como a reatividade para IFI-LANA e a detecção de DNA/HHV-8 na saliva. Houve uma tendência dos subtipos B e C de HHV-8 serem detectados em pacientes com infecção profunda ou disseminada de SK. Estes resultados sugerem que a boca pode ser um sítio de latência da infecção por HHV-8 e confirmam a atuação de sangue, saliva e urina como fluídos potencialmente infectantes. / Since the discovery of the human herpesvirus 8 (HHV-8) as the etiological agent of Kaposi’s sarcoma (KS), several studies have been conducted in order to determine routes of virus transmission, mostly in endemic and at risk populations. The main of the present study was to determine target segments of the HHV-8 genoma and consequently infected bodily fluids. DNA sequences of ORF K1, ORF 25, ORF 26, ORF K8.1 and ORF 73 strategically localized in viral genoma were searched using nested PCR techniques in KS lesions (positive control), blood, saliva, and urine from 76 KS/aids patients, 19 HIV/aids patients, 4 classic KS patients, and among 11 healthy individuals (HIV-1 seronegative, without KS). HHV-8 subtypes were determined by PCR-RFLP of the ORF K1 (VR1), and HHV-8 antibodies by IFA-LANA and IFA-Lytic assays. The results obtained were analyzed according to epidemiological, clinical and laboratorial data, and the c2 test, logistic regression and odds ratio were applied to identify statistical association among variables in KS/aids and HIV/aids groups. The results obtained showed HHV-8 DNA in 80.2% of biopsies, 69.7% of blood, 59.2% of saliva, and 21% of urines from KS/aids group. Among HIV/aids patients, 47.4% resulted PCR positive in blood, 26.3% in saliva and urine. In classic KS cases, all biopsies and saliva resulted PCR positive, 67% in blood, and 33% in urine. The serology in KS/aids group showed 73.3% frequency of anti-latent antibodies, and 85.3% frequency of anti-lytic antibodies, while in HIV/aids group the frequencies were 15.8% and 47.4%, respectively. All classic KS cases resulted HHV-8 seroposite, while all individuals from control group resulted HHV-8 seronegative. Molecular characterization of 69 HHV-8 strains disclosed: 27 of subtype A, 13 of subtype B, 28 of subtype C, and 1 of subtype E. The ORF 26, ORF K8.1 and ORF 73 were the best segments for identifying HHV-8 DNA in bodily fluids. It was observed an association between antibodies to lytic antigens and the presence of HHV-8 in blood, and antibodies to latent antigens and the detection of HHV8 DNA in saliva of KS/aids patients. Indeed, HHV-8 subtypes B and C were detected mostly in disseminated KS cases. Taken together, the results obtained suggest that the mouth could be one site of HHV-8 latency, and confirm that blood, saliva and urine were potentially infectious bodily fluids.

The objective of this thesis is to design and implement a small scaleInternet Service Provider (ISP) for the NetCenter sub department atMälardalen University. The ISP is intended to give NetCenter a networkseparate from the University’s network, providing them with a moreflexible environment for lab purposes. This will give their students anopportunity to experience a larger backbone with Internet accessibility,which has not been previously available. At the same time it will place theteachers in control of the network in the NetCenter lab premises.The network is designed with a layered approach including an Internetaccess layer, a larger core segment and a distribution layer with aseparated lab network. It also incorporates both a public and a privateserver network, housing servers running e.g. Windows Active Directory,external DNS services, monitoring tools and logging applications. TheInternet access is achieved by peering with SUNET providing a full BGPfeed.This thesis report presents methods, implementations and results involvedin successfully creating the NetCenter ISP as both a lab network and anInternet provider with a few inevitable shortcomings; the most prominentbeing an incomplete Windows Domain setup.

Cette étude aborde la manière dont l’Orient-Express a été décrit, perçu et imaginé, et s’efforce de mesurer l’écart entre les représentations communes et ce qui se dégage d’un corpus de textes très divers à travers trois grands axes de réflexion : les évocations des itinéraires de l’Orient-Express, les discours tenus sur le train et ses voyageurs, les thématisations et récupérations littéraires dont il a fait l’objet. L’idée directrice du propos est de montrer comment l’Orient-Express, rêve programmé par de très efficaces campagnes publicitaires et suscité par un imaginaire géographique, historique et littéraire puissant, n’a pu pleinement convaincre les voyageurs, mais aussi les écrivains et les lecteurs qui, semble-t-il, ne cessent de déplorer la disparition d’un train et d’un voyage qui n’ont peut-être jamais existé ou qui ne sont jamais vraiment ceux qu’ils imaginaient. / The purpose of this study is to see how the Orient Express was perceived, described and fantasized, and to measure the gap between common representations and what appears in quite different texts through three major lines : the evocations of the routes of the Orient Express, the discourses on the train and its passengers, the thematizations and literary recuperations. It aims at showing how the Orient Express, a dream programmed by very effective advertising campaigns and sustained by powerful geographical, historical and literary images, could not fully convince travelers, but also writers and readers who, apparently, do not cease to mourn the disappearance of a train and a travel that have perhaps never existed or that are never actually those they dreamt of.

This thesis presents two new routing problems, both with objective functions focused on relative positioning of teams during the routing horizon. The relative positioning results in temporal and spatial dependencies among routes and is quantified with a nonlinear dispersion metric, designed to evaluate the instantaneous distances among teams over a time interval. This metric allows the design of objective functions to approximate teams during routes execution, when minimized, or disperse them, when maximized. Both approximation and dispersion are important routing characteristics in some practical applications, and two new optimization problems are proposed with these opposite objectives. The first one is a variation of the Multiple Traveling Salesman Problem, and its goal is to find a set of tours where the salesmen travel close to each other, minimizing dispersion. A Local Search Genetic Algorithm is proposed to solve the problem. It includes specialized genetic operators and neighborhoods. A new set of benchmark instances is proposed, adapted for the new problem from literature instances. Computational results show that the proposed approach provides solutions with the desired characteristics of minimal dispersion. The second problem is a bi-objective arc routing problem in which routes must be constructed in order to maximize collected profit and dispersion of teams. The maximization of the dispersion metric fosters the scattering of the teams during routing procedure. Usually, profit and dispersion objectives are conflicting, and by using a bi-objective approach the decision maker is able to choose a trade-off between collecting profits and scattering teams. Two solution methods are proposed, a Multi-objective Genetic Algorithm and a Multi-objective Genetic Local Search Algorithm, both specialized in order to exploit the characteristics of the problem. It is demonstrated, by means of computational experiments on a new set of benchmark instances, that the proposed approach provides approximation sets with the desired characteristics. / Esta tese apresenta dois novos problemas de roteamento, ambos com funções objetivo voltadas para o posicionamento relativo das equipes durante o horizonte de roteamento. O posicionamento relativo resulta em uma dependência temporal e espacial entre rotas e é quantificado com uma métrica de dispersão não-linear, projetada para avaliar as distâncias instantâneas entre as equipes ao longo de um intervalo de tempo. Esta métrica permite a concepção de funções objetivo para aproximar as equipes durante a execução das rotas, quando minimizada, ou para dispersá-las, quando maximizada. Tanto a aproximação quanto a dispersão são características importantes de roteamento em algumas aplicações práticas, e dois novos problemas de otimização são propostos com esses objetivos opostos. O primeiro é uma variação do Problema de Múltiplos Caixeiros Viajantes, e seu objetivo é encontrar um conjunto de rotas em que os caixeiros viajam próximos uns dos outros, minimizando a dispersão. Um Algoritmo Genético com Busca Local é proposto para resolver o problema. Ele inclui operadores genéticos e vizinhanças especializados. Um novo conjunto de instâncias é proposto, adaptado para o novo problema de instâncias da literatura. Resultados computacionais mostram que a abordagem proposta proporciona soluções com as características desejadas de dispersão mínima. O segundo problema é um problema de roteamento de arcos biobjetivo em que as rotas devem ser construídas de modo a maximizar o lucro recolhido e o distanciamento entre as equipes. A maximização da métrica promove a dispersão das equipes durante a execução das rotas. Normalmente, os objetivos de lucro e dispersão são conflitantes, e com uma abordagem biobjetivo o tomador de decisão é capaz de avaliar a troca entre a coleta de lucros e a dispersão de equipes. Dois métodos de solução são propostos, um Algoritmo Genético Multiobjetivo e um Algoritmo Genético Multiobjetivo com Busca Local, ambos especializados para explorar as características do problema. É demonstrado, por meio de experimentos computacionais sobre um novo conjunto de instâncias, que a abordagem proposta fornece conjuntos de aproximação com as características desejadas.

Consider the problem of maximizing the revenue generated by tolls set on a subset <p>of arcs of a transportation network, where origin-destination flows (commodities) are assigned to shortest paths with respect to the sum of tolls and initial costs. <p>This thesis is concerned with a particular case of the above problem, in which all toll arcs are connected and constitute a path, as occurs on highways. Further, as toll levels are usually computed using the highway entry and exit points, a complete toll subgraph is considered, where each toll arc corresponds to a toll subpath. Two <p>variants of the problem are studied, with or without specific constraints linking together the tolls on the arcs. <p>The problem is modelled as a linear mixed integer program, and proved to be NP-hard. Next, several classes of valid inequalities are proposed, which strengthen important constraints of the initial model. Their efficiency is first shown theoretically, as these are facet defining for the restricted one and two commodity problems. <p>Also, we prove that some of the valid inequalities proposed, together with several <p>constraints of the linear program, provide a complete description of the convex hull <p>of feasible solutions for a single commodity problem. Numerical tests have also been conducted, and highlight the real efficiency of the valid inequalities for the multi-commodity case. Finally, we point out the links between the problem studied in the thesis and a more classical design and pricing problem in economics. /<p><p><p>Considérons le problème qui consiste à maximiser les profits issus de la tarification d’un sous-ensemble d’arcs d’un réseau de transport, où les flots origine-destination (produits) sont affectés aux plus courts chemins par rapport aux tarifs et aux coûts initiaux. Cette thèse porte sur une structure de réseau particulière du problème ci-dessus, dans laquelle tous les arcs tarifables sont connectés et forment un chemin, <p>comme c’est le cas sur une autoroute. Étant donné que les tarifs sont habituellement déterminés selon les points d’entrée et de sortie sur l’autoroute, nous considérons un sous-graphe tarifable complet, où chaque arc correspond en réalité à un sous-chemin. Deux variantes de ce problème sont étudiées, avec ou sans contraintes <p>spécifiques reliant les niveaux de tarifs sur les arcs. <p>Ce problème peut être modélisé comme un programme linéaire mixte entier. Nous prouvons qu’il est <p>NP-difficile. Plusieurs familles d’inégalités valides sont ensuite proposées, celles-ci renforçant certaines contraintes du modèle initial. Leur efficacité est d’abord démontrée de manière théorique, puisqu’il s’agit de facettes <p>des problèmes restreints à un ou deux produits. Certaines des inégalités valides proposées, ainsi que plusieurs contraintes du modèle initial, permettent aussi de donner une description complète de l’enveloppe convexe des solutions réalisables d’un problème restreint à un seul produit. Des tests numériques ont également <p>été menés, et mettent en évidence l’efficacité réelle des inégalités valides pour le problème général à plusieurs produits. Enfin, nous soulignons les liens entre le problème de tarification de réseau étudié dans cette thèse et un problème plus classique de tarification de produits en gestion. <p> / Doctorat en Sciences / info:eu-repo/semantics/nonPublished

Comment l’imaginaire des lieux issu de la littérature contribue-t-il à valoriser un territoire ? À l’heure où des territoires ruraux, soucieux de renforcer leur attractivité, mènent des actions visant à renouveler leur image, la littérature patrimonialisée peut être considérée comme une ressource : maisons d’écrivains, routes ou sentiers littéraires contribuent ainsi à l’inscription territoriale d’une littérature et de ses imaginaires. Cette thèse s’intéresse à l’invention de tels lieux, à leur animation et à leur intégration territoriale. Elle traite aussi de leur réception et de leur appropriation par les habitants et les touristes. Une analyse statistique des maisons d’écrivain en France dresse une typologie qui souligne les spécificités structurelles, spatiales et organisationnelles de ces lieux polymorphes. En complément,des études de cas renseignent sur la singularité de la relation entre l’auteur et le lieu, et sur la dynamique de la maison en tant que projet de territoire multi-acteurs. Deux méthodes sont mises en œuvre afin de saisir les représentations des visiteurs : une enquête par questionnaire, prolongée par l’analyse d’une voie plus créative et sensible d’expression, les livres d’or. L'analyse des questionnaires souligne la diversité des motifs de visite, non exclusivement littéraires. L'étude des livres d'or met en évidence la dimension immersive d’une expérience où les émotions vont à la rencontre des souvenirs et des imaginaires. Une typologie multiscalaire de parcours littéraires est ensuite réalisée, enrichie par des études de cas. Du Berry à la Provence, des Cévennes au Québec en passant par le Livradois, des parcours littéraires proposent de découvrir une région en compagnie d’un écrivain et de personnages imaginaires. Transcendant l’habituelle démarcation entre le réel et la fiction, ils redéfinissent ainsi la notion d’authenticité. L'ensemble des éléments analysés dans la thèse concourt à qualifier une forme de tourisme combinant connaissance, imaginaire et expérience des lieux, dressant les contours d’une nouvelle pratique touristique de l’espace : celle d’un tourisme littéraire tourné sur l’itinérance et la créativité / How does the imaginary of places stemming from literature contributes to enhance a territory? At a time when rural areas, aspiring to strengthen their attractiveness, take actions to renew their image, the literary heritage can be considered a resource: writers' houses, routes or literary trails thus contribute to the territorial inscription of literature and its imagination. This thesis is interested in the creation of such places, in their animation and in their territorial integration. It also deals with their reception and with their appropriation by the inhabitants and tourists. A statistical analysis of writer's houses in France allows for a typology which underlines the structural, spatial and organizational specificities of these polymorphic places. In addition, case studies inform about the peculiarities of the relation between author and place, and about the dynamics of the house as multi-actors territorial project. Two methods are implemented to seize the visitors’ representations: a survey by questionnaire, extended by the analysis of a more creative and more sensitive way of expression, visitors' log (« livres d’or »). The analysis of questionnaires underlines the diversity of the motives for visits which are not exclusively literary. The study of visitors' log highlights the immersive dimensions of an experience where feelings meet memories and imagination. A multiscalar typology of literary routes is then realized, enriched by case studies. From Berry to Provence, from the Cévennes to Quebec via Livradois, literary routes propose the exploring of a region together with a writer and imaginary characters. They so redefine the notion of authenticity by transcending the usual demarcation between the reality and fiction. All the analyzed elements contribute to consider a form of tourism combining knowledge, imagination and experimentation of places, drawing the outlines of a new tourist practice of space : that of a literary tourism focused on itinerancy and creativity