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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.
1

Metodologia para a avaliação de medidas voltadas à distribuição urbana de cargas através do uso da microssimulação de tráfego. / Methodology for urban freight policies evaluation using traffic microsimulation.

Zambuzi, Nathalia de Castro 14 August 2015 (has links)
O presente trabalho trata da avaliação de medidas voltadas à distribuição urbana de cargas considerando ser essa uma etapa fundamental do processo de tomada de decisão, pois permite a análise dos possíveis resultados acerca dos objetivos pretendidos, os quais geralmente estão relacionados à diminuição dos congestionamentos de veículos e das emissões de gases poluentes. Considerando que grande parte dos problemas decorrentes da distribuição urbana ocorrem localmente, no nível desagregado, propõe-se um procedimento que dê subsídios ao desenvolvimento de uma metodologia para a avaliação de medidas através da microssimulação de tráfego. Isso porque a microssimulação permite um alto nível de detalhe na modelagem e na observação do comportamento dos veículos, o que é essencial para a quantificação dos possíveis impactos locais gerados pelos veículos de carga. A integração entre as coletas de dados e os modelos que compõem o procedimento forneceu os dados necessários à representação dos movimentos dos veículos de carga no VISSIM, onde foram simulados três diferentes cenários, cada um representando alterações impostas por diferentes medidas em avaliação. A aplicação do procedimento proposto, a modelagem no VISSIM e os resultados da microssimulação permitiram a ponderação sobre o uso dessa técnica para a avaliação de medidas voltadas à distribuição urbana de cargas, considerando suas vantagens e limitações. / The present research deals with the evaluation of urban freight policies, considering this is fundamental for the decision making process of a policy implementation. Evaluation allows an analysis of the possible policy effects compared to its intended objectives, which are generally related to reductions in traffic congestion and pollutant emissions. Whereas most of the problems caused by urban distribution occur locally, in the disaggregated level, we propose a procedure that supports the development of a methodology for evaluating freight policies through traffic microsimulation. That\'s because this technique allows a high level of detail in modeling and observation of vehicles\' behavior, which is essential for quantifying the likely local impacts generated by freight vehicles. The procedure is based on a set of integrated data collections and models, which provided the data for representing freight vehicles movement in VISSIM, were three different scenarios, each one representing changes imposed by different freight policies, were simulated. The application of the proposed procedure, the VISSIM\'s modeling process and the microsimulation results allowed the weighing for the use of this technique in evaluating urban freight policies, considering its advantages and limitations.
2

Metodologia para a avaliação de medidas voltadas à distribuição urbana de cargas através do uso da microssimulação de tráfego. / Methodology for urban freight policies evaluation using traffic microsimulation.

Nathalia de Castro Zambuzi 14 August 2015 (has links)
O presente trabalho trata da avaliação de medidas voltadas à distribuição urbana de cargas considerando ser essa uma etapa fundamental do processo de tomada de decisão, pois permite a análise dos possíveis resultados acerca dos objetivos pretendidos, os quais geralmente estão relacionados à diminuição dos congestionamentos de veículos e das emissões de gases poluentes. Considerando que grande parte dos problemas decorrentes da distribuição urbana ocorrem localmente, no nível desagregado, propõe-se um procedimento que dê subsídios ao desenvolvimento de uma metodologia para a avaliação de medidas através da microssimulação de tráfego. Isso porque a microssimulação permite um alto nível de detalhe na modelagem e na observação do comportamento dos veículos, o que é essencial para a quantificação dos possíveis impactos locais gerados pelos veículos de carga. A integração entre as coletas de dados e os modelos que compõem o procedimento forneceu os dados necessários à representação dos movimentos dos veículos de carga no VISSIM, onde foram simulados três diferentes cenários, cada um representando alterações impostas por diferentes medidas em avaliação. A aplicação do procedimento proposto, a modelagem no VISSIM e os resultados da microssimulação permitiram a ponderação sobre o uso dessa técnica para a avaliação de medidas voltadas à distribuição urbana de cargas, considerando suas vantagens e limitações. / The present research deals with the evaluation of urban freight policies, considering this is fundamental for the decision making process of a policy implementation. Evaluation allows an analysis of the possible policy effects compared to its intended objectives, which are generally related to reductions in traffic congestion and pollutant emissions. Whereas most of the problems caused by urban distribution occur locally, in the disaggregated level, we propose a procedure that supports the development of a methodology for evaluating freight policies through traffic microsimulation. That\'s because this technique allows a high level of detail in modeling and observation of vehicles\' behavior, which is essential for quantifying the likely local impacts generated by freight vehicles. The procedure is based on a set of integrated data collections and models, which provided the data for representing freight vehicles movement in VISSIM, were three different scenarios, each one representing changes imposed by different freight policies, were simulated. The application of the proposed procedure, the VISSIM\'s modeling process and the microsimulation results allowed the weighing for the use of this technique in evaluating urban freight policies, considering its advantages and limitations.
3

MULTI-AGENT MODELING TO EVALUATE URBAN FREIGHT TRANSPORT POLICY MEASURES USING JOINT DELIVERY SYSTEMS / 共同配送システムを用いた都市物流施策評価のためのマルチエージェントモデリング

Wang-A-Pisit Ornkamon 24 September 2014 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第18573号 / 工博第3934号 / 新制||工||1604(附属図書館) / 31473 / 京都大学大学院工学研究科都市社会工学専攻 / (主査)教授 谷口 栄一, 准教授 宇野 伸宏, 准教授 QURESHIAli Gul / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
4

Selective vehicle routing problems in collaborative urban transport networks / Problèmes de tournées sélectives dans les réseaux collaboratifs de transport urbain

Ben Said, Asma 09 April 2019 (has links)
Le but de ce travail de thèse réside dans la planification de la distribution urbaine des marchandises dans un système de transport collaboratif. Cette collaboration consiste à échanger les demandes de transport entre transporteurs afin d'améliorer l'efficacité de leurs opérations. Cela revient à minimiser la distance parcourue par les camions et à maximiser le profit collecté des clients, notamment en recourant à des variantes du problème de tournées de véhicules plus adaptées au contexte collaboratif. Le problème opérationnel sous-jacent est donc le problème de tournées de véhicules sélectives dans lequel le service de tous les clients n'est pas obligatoire par contre un "profit" est collecté lors du service d'un client. Dans cette thèse, nous traitons le problème de tournées de véhicules sélectives avec contraintes de temps et de capacité (Capacitated Team Orienteering Problem - CTOP). Nous proposons une métaheuristique qui alterne entre deux espaces de recherche. Des procédures de découpage optimal et de concaténation permettent de passer d'un espace à un autre. D'autre part, en considérant des demandes de collecte et de livraison, nous traitons deux variantes sélectives du problème de collecte et de livraison (Pickup and Delivery Problem - PDP) : le PDP avec fenêtres de temps et demandes obligatoires (PDPTWPR) et le PDPTWPR avec demandes groupées. La première variante consiste à choisir parmi les demandes de transport optionnelles quelles demandes à servir en plus des demandes obligatoires. Nous développons des métaheuristiques pour traiter les cas mono-objectif et multi-objectif du problème. Le PDPTWPR avec demandes groupées prend en considération les demandes de transport qui doivent être servies par un même transporteur. Finalement, nous considérons la variante sélective dans laquelle les marchandises sont distribuées d'un même dépôt vers les clients (Capacitated Profitable Tour Problem - CPTP). L'objectif est de maximiser la différence entre le coût et le profit. Pour résoudre ce problème, nous proposons un algorithme de résolution exacte basé sur la programmation linéaire en nombres entiers à laquelle nous ajoutons plusieurs inégalités valides spécifiques à ce problème. Des expérimentations ont été conduites sur plusieurs classes d'instances afin de montrer l'efficacité de nos approches. / The goal of this thesis is to plan urban freight distribution in a collaborative logistic system. The collaboration consists in exchanging transportation requests between carriers to increase the efficiency of their operations. More precisely, when solving variants of the wellknown vehicle's routing problems in collaborative context, less kilometers can be driven and higher prices can be collected. The underlying operational problem is therefore the selective vehicle routing problem in which not all customers can be served, but a "profit" is gained for each served one. In this thesis, we firstly address the Capacitated Team Orienteering Problem (CTOP), a selective variant of the VRP in which capacity and travel time limitations are imposed to vehicles. We propose a variable space search metaheuristic that alternates between two different search spaces to solve CTOP. Then, we consider pickup and delivery requests to study two variants of the selective pickup and delivery problem: the PDP with Time Windows and Reserved requests (PDPTWPR) and the Clustered PDPTWPR. The first aims to choose suitable selective requests to be transported in addition to reserved ones. Metaheuristics are proposed to deal with the single-objective and the multi-objective sides of the problem. The second takes into consideration groups of requests that must be served by only one carrier. Finally, we consider the Capacitated Profitable Tour Problem (CPTP) in which goods need to be distributed from the depot to customers. We propose an exact method based on Integer Linear Programming to solve this problem. A set of cuts specific to CPTP is proposed in order to speed up the solution process. Experiments were conducted on a variety of instances of different sizes to demonstrate the effectiveness of our solution methods.
5

Problème d'implantation de plateformes de logistiques durables en milieu urbain / Location problem of sustainable logistics platforms in urban areas

Ndhaief, Nadia 09 March 2018 (has links)
L’environnement urbain est fortement ancré dans la gestion des flux logistiques. La mutualisation de ces différents flux apporte alors une solution qualitative répondant aux critères environnementaux, économiques et sociétaux. Cette thèse propose une approche pour la mise en place des centres de distribution urbains (CDU) en combinant la logistique de distribution avec la logistique inverse (flux montants et flux descendants). L’objectif principal de ces CDU est d'assurer un développement durable dans les villes modernes. L’hétérogénéité des pratiques de la logistique de distribution et de la logistique inverse constitue le principal verrou scientifique. La mutualisation de ces différents flux apporte alors une solution qualitative et durable dès lors qu’elle répond aux critères attendus : environnementaux, économiques et sociétaux. Dans un contexte de logistique globale, nous nous sommes basés sur les problèmes de localisation de plateformes HLP « Hub Location Problem » afin de formuler le problème de localisation des CDU selon un critère de maximisation du profit par le choix du meilleur emplacement parmi ceux disponibles. Nous avons calculé les localisations partiellement possibles, tout en garantissant le traitement des flux retournés (collecte, tri, revente) et aussi en tenant compte des coûts socio-environnementaux. Par la suite, nous avons utilisé des outils de résolution du modèle proposé via des algorithmes d’optimisation. L’efficacité de ces algorithmes a été confirmée par un ensemble de jeux de données et de rapports d’analyse d’impacts. La dynamique liée à la fiabilité des CDU dans l’exécution du service par la prise en compte d’une politique de coordination inter-CDU fait aussi partie de notre étude. Nous nous sommes intéressés à l’aspect de disponibilité pour garantir les livraisons à temps. En effet, l’indisponibilité du système peut être due aux pannes aléatoires, aux actions de maintenance préventive planifiées, etc. Par conséquent, nous présentons une solution qui permet de satisfaire la demande journalière de manière ponctuelle par l’intégration d’une approche collaborative entre les différents sites. Il s’agit d’un modèle d’optimisation de la politique de coordination inter-CDU avec une stratégie de sous-traitance des livraisons en cas d’indisponibilité / The urban environment is strongly involved in the management of logistics flows. The pooling of these different flows provides a qualitative solution ensuring environmental, economic and societal criteria. The thesis objectives aim at supporting Urban Distribution Centers (CDU) by combining distribution logistics with reverse logistics (upstream flows and downstream flows), thereby ensuring sustainable development in modern cities. The heterogeneity of the distribution logistics practices and the reverse logistics define the core of this thesis. Sharing these different flows provides a qualitative and sustainable solution as long as it meets the aforementioned criteria (environment, economy and society). Our approach is based on the Hub Location Problem to formulate the location problem of UDC while maximizing the profit and choosing the best available location. We proceed by identifying potential available locations, while guaranteeing returned flows management (collection, sorting, resale, etc.) and reducing pollution impact. Moreover, we simulate our optimised model with simulation tools using optimization algorithms. The effectiveness of these algorithms are validated based on generated outputs (set of data) inspired by real world scenarios. Reliability is a part of this work when dealing with UDC deployment. The unavailability of the system may be due to random failures, planned preventive maintenance actions, etc. Therefore, we present a solution supporting daily demands by integrating a collaborative approach between different sites. This approach is based on inter-CDU coordination policy with a strategy of subcontracting deliveries dealing with unavailability
6

Efficient city logistics : Can travel patterns of goods and people be intertwined?

Merkel, Pontus January 2015 (has links)
Optimizing city logistics is a topic of great importance for big cities today. Even though the environmental- and economical consequences of the increasing goods transportation fleet has been present for quite some time, actions from affected stakeholders has not been taken until just recently.  In this brief 9 week project the aim has been to,  from a design point-of-view, in this complex topic, give a suggestion and raise a discussion onto how goods transportation in cities can be made in the future.  The basic idea is to get the consignments as close to the consignees and their travel patterns as possible. Public transportation networks are an existing grid where people are moving around and can potentially be used for combined transport of goods and people. The outcome of this concept is focusing on light parcel delivery towards private consignees, due to the increasing e-commerce trend. By using small transporter vehicles connected to buses, light parcels can be distributed throughout a city and easily accessible for consignees at the bus stops.  The transporter vehicle developed through this project aims to conceptualize connectivity and integration between mobility and parcel delivery services, to ease the every day life of urban citizens as well as decrease the environmental- and economical impacts which the distribution vehicle-fleet of today entails.  The design of the transporter vehicle is an interpretation of how a autonomous distribution vehicle can look like in a future city environment where the integration of public-utility-vehicles is of greater importance.
7

Le redéploiement technique et organisationnel des réseaux de messagerie dans les territoires / The technical and organisationnal redeployment of French groupage networks

Launay, Pierre 06 March 2018 (has links)
La messagerie est le segment du transport terrestre de marchandises dédié au transport d’envois de détail (colis, sacs, petits lots palettisés) sur des longues distances. Elle s’appuie sur une organisation réticulaire pour traiter conjointement des envois appartenant à différentes chaînes logistiques, afin d’optimiser les capacités de chargement des véhicules. Au cours des vingt dernières années, elle a accompagné le redéploiement des systèmes de production et de distribution dans les territoires, et a intégré les outils de la révolution numérique sur les plans matériel (automatisation) et informationnel (technologies de l’information et de la communication). Dans leurs dimensions techniques et organisationnelles, les réseaux de messagerie n’ont plus grand-chose à voir avec ce qu’ils étaient à la fin du siècle dernier. Pourtant, aucun travail de recherche ne s’est penché sur cette question. Cette thèse propose de caractériser les modalités d’adaptation technique et organisationnelle des réseaux de messagerie aux mutations des systèmes de production et de distribution dans les territoires depuis la fin du XXe siècle. Elle s’appuie sur des informations recueillies auprès de professionnels de la messagerie et des données ouvertes. Elle révèle une multiplication du champ des possibles des envois de messagerie en termes de délais et de couverture géographique, et une segmentation des réseaux de messagerie selon le seul critère de conditionnement des marchandises, déterminant le potentiel d’automatisation de leur traitement dans les réseaux. A l’heure de l’intégration européenne et de la globalisation des chaînes logistiques, cette thèse propose de nouveaux outils pour comprendre le déploiement des réseaux de messagerie dans les territoires / The French concept of “Messagerie” describes both less-than-truckload (LTL) and parcel delivery operations based on network organizations. These transport operations rely on the consolidation and groupage of shipments belonging to different kind of supply chains. In the last two decades, this activity adapted to the evolution of production and distribution systems and has integrated the digital revolution tools in its internal organization. The French LTL and parcels networks have little in common with what they were in the ‘90s. Yet, their transformations are largely ignored in the scientific literature. This thesis proposes an analysis of the organizational and technical adaptation of French LTL and parcels networks to the evolution of the production and distribution systems in the last two decades. It is based on information gathered from professionals and open data. It reveals an extend of the range of possibilities offered by the transport networks in terms of delays and geographic coverage, and a technical specialization of these networks according to the size, weight and packaging of the goods transported, which determine their potential for automation. At a time of globalization, this thesis offers new tools to understand the deployment of transport networks in the territories

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