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Hairoud, Siham. "Modélisation dynamique des canaux MIMO pour les transports ferroviaires". Thesis, Poitiers, 2012. http://www.theses.fr/2012POIT2256/document.
Pełny tekst źródłaThe exploitation, control and signalling systems for metro and especially modern driverless metros, are based on two families of radio communication systems Wireless : vital transmissions for signalling and train control low-flow and nonvital transmissions with very high bandwidth for video-tracking systems, telediagnosis, customer information, etc.. During the implementation ofsuch transmission systems, the industrial must therefore ensure the metro operator performance on throughput and transmission quality in terms of packet loss information. Therefore, understanding the behavior of the propagation channel is a key to predict and improve performance of transmission systems.The aim of this thesis is twin and concerns :• On the one hand, the computation time reduction of a 3D ray tracing simulator that accurately predicts the behavior of the propagation channel, but it is expensive in times of calculation for dynamic simulations. We propose here a new method based on three visibility criteria to simplify the geometry description of the environment without degrading the characteristic parameters prediction of the propagation channel ;• On the other hand, the construction of a new model for MIMO propagation channel dynamics in straight tunnel of rectangular section which will optimize transmission systems multi-antennary (MIMO) applications for wireless transmission in metros tunnel. This model draws broadly from the channel model used in the standard WINNER and is fed by the results extracted from the 3D ray tracing channel simulator. The results obtained in this thesis are encouraging and offer many opportunities
Masmoudi, Walid. "Mutation de produit : conception et modélisation d'un T.G.V. Bogie en matériaux composites". Paris, ENSAM, 1993. http://www.theses.fr/1993ENAM0027.
Pełny tekst źródłaThe third generation TGV sets (French Railways high spee trainsets) will be double-decker trainsets (also known as TGV - 2N) travelling at 350 km/h in commercial service. This study relates to the insertion of composite materials in order to reduce the the weight of the TGV 2N bogie structure. A research on a new concept has been conducted and led to the specification of an experimental model of bogie in box shaped elements obtained by a statification method. The behaviour of the materials has been charaterized both in staic and in fatigue where damage laws and wohler curves have been estabilished. The static and dynamic behaviour of the experimental model has been modelled. The modelling was then used to validate the concept in relation to the static resistance criteria and to modal analysis prosperties and especially to validate finite elements calcultaion models thanks to SAMCEF software. Lastly, the validity of the concept in relation to the fatigue has been experimentally achieved and it was possible to draw degradation and failure laws. This study will be able to be used as the basis of more precise research on a new industrial concept of a bogie made of composite materials which will take into account both functional and economic criteria
Trépanier, Martin. "Modélisation totalement désagrégée et orientée-objet appliquée aux transports urbains". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0020/NQ48896.pdf.
Pełny tekst źródłaEl, Hmam Mohamed Said. "Contribution à la modélisation et à la simulation hybride du flux de trafic". Artois, 2006. http://www.theses.fr/2006ARTO0206.
Pełny tekst źródłaThis thesis concerns the hybrid traffic flow modelling and simulation. This approach uses jointly the two classical traffic flow models ; macroscopic and microscopic. It is a matter of adapting the representation to the studied phenomenon. Indeed, the macroscopic model is well adapted to the motorway network representation whereas the microscopic one makes it possible to describe an urban network more finely. Thus, we can obtain detailed information of the traffic state on a crossroads (for example) using the microscopic model and to implement traffic control laws synthesized from a macroscopic one. The final objective is to design and implement a decision-making tool allowing us to test and validate various traffic control strategies. For that, we initially developed a microscopic model founded on the paradigm agent. Then, we have proposed a coupling procedure, which makes it possible to ensure the conservation and the continuity of flow through the transition zone that connect the two worlds ; microscopic and macroscopic. The simulation results of the developed hybrid model show that it is possible to cohabit two models (microscopic and macroscopic) within the same system. To illustrate the relevance of the hybrid model, a traffic flow control application has been proposed. The results show that the vehicles travel total time was reduced. The proposed model represents a first version of a traffic flow hybrid simulator, which will remain to be developed within the furthers works
Vojak, Robert. "Analyse et modélisation multi fractales de signaux complexes : application au trafic routier". Paris 9, 1996. https://portail.bu.dauphine.fr/fileviewer/index.php?doc=1996PA090016.
Pełny tekst źródłaMasson, Sophie. "Les interactions entre système de transport et système de localisation en milieu urbain et leur modélisation". Lyon 2, 2000. http://theses.univ-lyon2.fr/documents/lyon2/2000/smasson.
Pełny tekst źródłaThis research proposes an interactive operational transport and land use model like a tool of transport planning aid. The construction of this model falls under a will to exceed the traditional methodology of the strongly criticized models of transport owing to the fact that they badly take into account the character derived of the travel demand, in particular, the locations of the residents and of the activities, generators of travel, are regarded as fixed. In the long run, the interactions between transport and land use must be explicitly integrated. The modification of the conditions of travel has impacts on the urban forms and the effect of these forms on the travel demand is not a doubt. The implementation of such a model requires an analysis of the travel demand, initially, and a conceptual and theoretical analysis of the mechanisms of interaction between transport and land use in the second time. That is the subject of the first part of this work. The second part of the thesis is devoted to the development of an interactive model of transport and urbanisation. This one articulates three submodels: a model of urban development which takes as a starting point the theory of the urban economic base, a model of urban structure which estimates the distribution of the locations of the residents and the induced activities. Lastly, a model of travel which expresses the market equilibrium of the urban transport obtained through the stages of generation, spatial distribution, modal split and assignment. The dynamics of long term of the model is obtained by the introduction of retroactive loops. The model brings certain lesson for the transport planning. The latter must fall under a total step and of long term, and must be considered in coherence with the urban planning
Lammoglia, Adrien. "Analyse et modélisation multi-agents de transports flexibles : Comparaison de services français et sénégalais". Phd thesis, Université d'Avignon, 2013. http://tel.archives-ouvertes.fr/tel-00903655.
Pełny tekst źródłaBlondeau, Patrice. "Caractérisation et modélisation des transports de polluants dans les environnements intérieurs". Habilitation à diriger des recherches, Université de La Rochelle, 2008. http://tel.archives-ouvertes.fr/tel-00351567.
Pełny tekst źródłaGiorgi, Florence. "Prise en compte des transports en commun de surface dans la modélisation macroscopique de l'écoulement du trafic". Lyon, INSA, 2002. http://theses.insa-lyon.fr/publication/2002ISAL0101/these.pdf.
Pełny tekst źródłaIn an urban congested background where the number of personal vehicles keeps on growing, managing other vehicles becomes more and more useful and necessary. To evaluate different strategies, two types of traffic flow models can be used : microscopic models describe each individual vehicle and macroscopic models consider the flow in a global and homogenous manner. Stradabus proposes to adapt a macroscopic model in a way to take buses and their interaction with traffic into account as could behave a moving bottleneck. The model resolution introduces a new discretisation scheme around the bus. Measures have been experimented in the field that allowed calibration and validation of the model
Labergri, Fabien. "Modélisation du comportement dynamique du système pantographe-caténaire". Ecully, Ecole centrale de Lyon, 2000. http://www.theses.fr/2000ECDL0012.
Pełny tekst źródłaThis study, a collaboration between ECL-SNCF-FAIVELEY TRANSPORT, proposes a mechanical model of current collection. It led to simulation software written in C++, named PACAT3D. The work includes the development of pantograph and of catenary models and numerical methods to deal with and the pantograph / catenary coupling equations. The pantograph is modelled with the help of multibody methods. Absolute nodal coordinates are used in order to simplify the definition of the joints. The non-linear damper of the pantograph has been thoroughly studied. A large experimental work has been used as a guideline for the models development and allowed their validation. The catenary is modelled by finite-elements. The non-linearity arising from the droper's release are taken into account. A study on the three dimension behaviour of the catenary has been carried out. Techniques to handle systems of equations with constraints are describe : their transform to fit with explicit integration methods, static calculus, constraint relaxation and reestablishment. Many strategies are tested in order to find out the contact force between the mobil pantograph and the discretized catenary; particulary the use of wire elements obtained through modal synthesis. An analytical method enable the validation of the pantographjcatenary coupling. It applies to the stationary response study of a moving pantograph under an infinite periodical catenary. Based upon the Fourier series decomposition of the variables expressed in the moving frame, it leads to the resolution of an eigen value problem
Coquio, Julien. "La performance adaptative des systèmes de transports collectifs : modélisation, mesures de vulnérabilité et évaluation quantitative du rôle de l'information des voyageurs dans la régulation des situations perturbées". Thesis, Tours, 2008. http://www.theses.fr/2008TOUR1807.
Pełny tekst źródłaIIn a perspective of modal transfer, adaptative performance is an important factor in the development of public transport systems. Tools are therefore necessary to allow estimation of their vulnerability to perturbations, as well as that of the role played by specific actions like passengers’ information. The PERTURB model and the simulation platform developed in this research aim to measure the structural and functional vulnerability of public transport, as well as the role played by passengers’ information in the regulation of disrupted situations. This study explores three theoretical fields : systems’ theory, graphs theory and multi-agents systems. Simulations are used in a field study (the region of Ile-de-France) and in theoretical transportation systems. These simulations allow us not only to formulate recommendations, regarding transport planning and passengers’ information, but they also rise new issues. How can passengers’ information be integrated in order to get the optimal management of disrupted situations ? Is it possible to deliver clear information while avoiding excessive transfer of passengers’ flow at the same time ?
Spiller, Martin Werner. "Modélisation physique et numérique d'écoulements et transports en milieux hétérogènes fracturés : écoulement à haut reynolds et transport particulaire réactif". Toulouse, INPT, 2004. http://ethesis.inp-toulouse.fr/archive/00000066/.
Pełny tekst źródłaGosset, Stéphanie. "Le placement des individus comme organisation spatiale des habitacles de transport public urbain : Une modélisation littéraire au service de l'innovation en design". Thesis, Tours, 2018. http://www.theses.fr/2018TOUR1804/document.
Pełny tekst źródłaThe French rail transport company Alstom Transport inquires whether new usages are emerging in urban public transport vehicles. The systemic approach has been chosen as a theoretical frame to respond to this question. This approach enables to examine the organization of the individual-passenger compartment system. Structured observation has been conduct in 12 cities (5 countries). Data analysis combining qualitative and quantitative methodologies, allows describing the placement based on 2 scales (the passengers compartment and the individual). The sense of the sitting position and the possibility to lean on has been brought to light as well as the spatial organization of activities. A potentially emerging usage could be observed. It interrogates a possible evolution of the organization of placement, and opens new research perspectives regarding the spatial organization of activities
Motamedi, Kiarash. "Contribution à la modélisation intégrée de la dynamique régionale et des transports : application à la région parisienne". Cergy-Pontoise, 2008. http://www.theses.fr/2008CERG0369.
Pełny tekst źródłaThis study contributes to the development of an integrated transportation and land-use model by a case study on Paris region. Our modelling approach is based on micro simulation methiod and we are using disaggregated adata. We present a modular architecture for integrated model composed by seprate models for transportation and land use. The transportation model has two parts : the first one to compute the demand O D matrix and the second one a dynamic traffic assignment model (METROPOLIS). The regional (land use) dynamics is modelled within the UrbanSim's framework. We are studying households and businesses in terms of their evolution and their location choice. A A hedonic real estate model is estimated to produce the price signals as a determinant of location choice. We conclude by a demonstration of integrated model results. Our study shows the capacity of this method to represent the regional evolution and also suggested different adaptations to the original modelling framework
Marissal, Alain. "Collision bidimensionnelle dans les transports guidés : Expérimentation et modélisation des risques de chevauchement". Valenciennes, 1993. https://ged.uphf.fr/nuxeo/site/esupversions/a3c3014d-5275-41b2-bd52-4225197636b6.
Pełny tekst źródłaSalem, Fatma. "Fiabilité et sécurité des systèmes embarqués communicants pour les transports : modélisation et optimisation". Thesis, Valenciennes, 2018. http://www.theses.fr/2018VALE0034.
Pełny tekst źródłaVehicle-to-anything (V2X) refers to an Intelligent Transportation System (ITS) where the vehicles and infrastructure systems are all interconnected with each other. This connectivity provides precise knowledge of the traffic situations across the entire road network which in turn helps to enhance traffic safety, reduce congestion time, avoid economic losses, in addition to enable a variety of novel ITS applications for road safety and passenger infotainment. V2X communications is based on two technologies; Dedicated Short-Range Communications (DSRC) which is an essential technology for realizing V2X and cellular networks which provide an o_-the-shelf potential solution for V2X communications. Although the research community has achieved much great progress on V2X study, there are still some challenges that need to be overcome and some key issues that need to be further investigated. This thesis considers two of the most prominent issues; reliability and security of V2X communications. From the reliability perspective, we first propose User Model-based Method to evaluate the capacity of IEEE 802.11p-based DSRC standard to meet the Quality-of-Service (QoS) requirements of safety messages dissemination. The novelty of the method lies in its application which avoids the problem of defining a Markovian model by determining the steady state moments of the induced delay process. This applicability feature provides important insights about IEEE 802.11p design parameters and its functionality leading to proposed reconfigurations for enhanced performance. Moreover, we propose Regenerative model, that we believe to be the first to address the problem of interconnected-traffic process characterization in large-scale hybrid V2X networks. The latter is a primary concern in achieving efficient and adequate operability for large-scale vehicular networks. From the security perspective, we introduce a new optimization methodology which ties the QoS requirements of different application classes with the basic design parameters of the contention resolution mechanism in IEEE 802.11p MAC protocol. In addition, a novel detection algorithm for jamming attacks in the vehicular environment is proposed. The algorithm utilizes the developed optimization methodology to de_ne a detection threshold. By integrating the sequential detection of change method it traces and detects jamming attacks whenever the threshold value is crossed. Analytical and simulation experimentations have been performed for each contribution to show the validity of the proposed methods/models and to prove their efficiency
Iordanova, Violina. "Contribution à la modélisation et la commande du trafic routier : approches par Bond Graph et commande par platitude". Artois, 2006. http://www.theses.fr/2006ARTO0207.
Pełny tekst źródłaThe works presented in this thesis deal with the modelling and traffic flow control in motorways. The main objective is to bring an effective response to the congestions problems whose socio-economic impacts are very significant. The proposed resolution is approached in two stages: the first, relates to the traffic flow modelling. Accordingly, our contribution aims at introducing a new point of view to enrich the existing macroscopic models. The suggested approach assimilates the traffic flow to a set of elementary volumes in circulation in the motorway sections. This approach is enriched by the use of the Bond Graph graphical formalism which allows to better represent the behaviours which govern the traffic and to deduce systematically the dynamical equations. The second step concerns the traffic flow control. In this context, our contribution rests on the introduction of the relatively recent concept called “differential flatness” to control the vehicles flow circulating in the motorways. The main characteristic of this control strategy lies in its capacity to ensure the trajectories generations and tracking without integration of any differential equations of the studied model. Finally, the association of the Bond Graph models and flatness based control are efficiently applied for the integrated traffic flow control bringing into play the ramp metering approach and the main traffic flow dynamic limitation. The simulation results validate the relevance of the suggested approaches and open some further perspectives for improvement and generalization of the traffic flow control for more complex motorways networks
Berdai, Abdelhamid. "Modélisation et simulation d'un réseau de transport public par une approche multi-agents". Besançon, 2004. http://www.theses.fr/2004BESA2035.
Pełny tekst źródłaThe work presented in this thesis focuses on the modelling and the simulation of bus transportation networks. The proposed approach is the design of a model based on multi-agents paradigm, which takes into account risks affecting the transportation network. These risks can changed according to several temporal or space variations. In order to analyze an urban public transportation system, a model based on multi-agents approach is elaborated. First, we determine the structure of transportations system as being as hierarchical organisations. Such a structure includes roles and their interactions. Then, we define a set of agents and we assign roles for each one. Interactions between agents are modelled by the interaction diagram. To simulate this model, the agent behaviour specification is necessary. The design process of transportation simulator allows us to describe the behaviour of each agent with the statechart formalism and thus we define a set of rules, which simplifies the behavioural agent model. The last step is to implement the simulator from models specified previously. We implement a human-machine interface, its configuration, and its parameter setting. Finally, we evaluate some parameters of transport quality of service by taking account risks which perturb the bus network
Komarov, Kostyantyn. "Une modélisation de l'arbitrage entre voiture particulière et transport collectif : application à la ville de Kharkov (Ukraine)". Lyon 2, 2001. http://theses.univ-lyon2.fr/documents/lyon2/2001/komarov_k.
Pełny tekst źródłaBelmonte, Mylène. "Automatisation intégrale de la ligne 1 : étude et modélisation du trafic mixte". Compiègne, 2008. http://www.theses.fr/2008COMP1752.
Pełny tekst źródłaThe current thesis takes place in the framework of fine 1 automation project. It is a project that consists of upgrading fine 1 (with drivers on-board) to unattended train operation (no drivers or agents on-board) without service interruption. It results a mixed fleet operation for a period of two years between manually driven trains and driverless ones. In this context, my research work consists of continuing in a first step the development of software destined to study and analyse the mixed fleet operation on fine 1. Once operational; the model has served as a simulation in two case studies that I elaborate in a second step. These two case studies aim to answer problematical matters affecting the management of the mixed trains running inside the terminal stations. They take into account two opposite constraints: people-staff safety on one hand and quality of service offered to passengers on the other hand. The analysis and the results of these two case studies will be described in the current PhD report
Bourrel, Emmanuel. "Modélisation dynamique de l'écoulement du trafic routier : du macroscopique au microscopique". Lyon, INSA, 2003. http://theses.insa-lyon.fr/publication/2003ISAL0073/these.pdf.
Pełny tekst źródłaTo satisfy road managers needs (in particular in terms of decision-making and evaluation of their actions of exploitation), many dynamic traffic flow models have been developed in order to represent propagation of vehicles on a road section. Those models describe traffic flow in a more or less aggregated way and are generally classified into two main groups: microscopic models, which are interested in the dynamics of individualized vehicles, and macroscopic models, more aggregated models which describe traffic as a fluid. One of the difficulties encountered in the study of those models is the great disparity of scales to be considered. The aim of this thesis is to look further into these scales problems (in particular by studying the link that exists between microscopic and macroscopic models) through the development of a hybrid model of traffic flow (a hybrid model is defined as the coupling between a microscopic model and a macroscopic model). The interest of a hybrid model is that it makes it possible to adapt the traffic flow model to the needs to model the various elements of a network. It is thus possible to describe some specific elements where the local phenomena of traffic flow can have global consequences with the microscopic model(toll station, on-ramp, roundabout. . . ) while preserving a global vision of the flow on the rest of the network with the macroscopic model. Although there are some models of this type in the literature, there is no global view of the problems related to hybridization. So it is very difficult to judge the relevance of existing models. This is why we propose in this thesis a general theoretical framework defining these models, in particular by determining the fundamental properties that a hybrid models must have to be valid. We then propose a new hybrid model based on a first order macroscopic model (the Lighthill-Whitham- Richards model). The characteristic of that model is that it makes it possible to take into account the diversity of vehicles behaviour in the microscopic part by introducing distributions on some parameters. The results provided by this model are then studied for three examples of application (one-way toll station, crossing between a major and a minor road, combination of two intersections) in which we show the interest of the coupling between microscopic and macroscopic models
Chanut, Stéphane. "Modélisation dynamique macroscopique de l'écoulement d'un trafic routier hétérogène poids lourds et véhicules légers". Lyon, INSA, 2005. http://theses.insa-lyon.fr/publication/2005ISAL0040/these.pdf.
Pełny tekst źródłaThe traffic composition is one of the phenomenon that road managers have to address. In particular a question arises: the impact on the flow of trucks. This thesis proposes a traffic flow model making it possible to describe the behavior of a heterogeneous traffic. This proposed model is a macroscopic one, with two classes. The traffic is described like a continuous flow and is assumed to be composed of two homogeneous classes: trucks and passenger cars, which are different from their speeds and their lengths. The model is completely solved and a numerical resolution is built with a Godunov scheme. A particular attention is paid to the passing phenomenon and its effects on the flow by a specific modelling. The applications of the model are numerous, in particular for what concerns the test of regulation strategies for a heterogeneous traffic
Jiang, Fei. "Choix modal et système logistique en transport de marchandises : Modélisation, analyse économique et prévision du comportement du chargeur". Marne-la-vallée, ENPC, 1998. http://www.theses.fr/1998ENPC9807.
Pełny tekst źródłaRaux, Charles. "De la modélisation des comportements à l'évaluation des politiques publiques : le cas des transports". Habilitation à diriger des recherches, Université Lumière - Lyon II, 2006. http://tel.archives-ouvertes.fr/tel-00115076.
Pełny tekst źródłaAuparavant, il m'a paru nécessaire d'apporter un éclairage épistémologique et méthodologique à mes travaux de conceptualisation, d'expérimentation et de modélisation. La mise en perspective que je propose, est structurée autour de questions comme le critère de démarcation de la science à travers la rigueur opératoire de sa méthode, les débats sur la marche du progrès scientifique entre théorie et expérience, l'alternative entre le rationalisme et le relativisme, le débat entre réalisme et instrumentalisme à travers les limites de l'expérimentation contrôlée en sciences sociales, et enfin, la causalité et le déterminisme partiel à l'œuvre dans les sciences sociales.
La synthèse de mes travaux est organisée selon trois thèmes de recherche principaux, à savoir la définition et la mesure des concepts utilisés, la modélisation du système de déplacements urbains, et la conception et l'évaluation d'instruments de régulation.
Au sujet du premier thème, j'illustre comment j'ai mis en œuvre une définition « opératoire » de la mobilité, et je discute comment cette définition évolue de concert avec les modèles-théories qui la représentent et la manipulent. Je montre également comment ce concept est utilisé dans le cadre d'une expérimentation contrôlée fictive – une méthode d'enquête interactive de simulation, dite de « réponses déclarées » – pour explorer « l'univers de choix » comportemental des individus en matière de mobilité quotidienne.
Ce concept de mobilité est mis en œuvre dans le développement de plusieurs modèles, deuxième thème de mes recherches. Le modèle stratégique de déplacements de l'agglomération lyonnaise s'est révélé particulièrement adapté comme outil de recherche, ainsi que pour l'exploration méthodologique de l'incertitude en matière de prévision. Certains développements techniques récents pour dépasser les limites du modèle sont exposés, notamment l'introduction d'un modèle de choix modal « prix-temps », sur la base de fondements micro-économiques. Finalement, des essais assez concluants de modélisation dynamique du système de déplacements urbains sont présentés, avec les exemples d'un modèle de régulation des transports publics et d'un modèle de choix d'heure de départ reposant sur un modèle de goulot.
Enfin, le troisième thème de mes recherches concerne la conception et l'évaluation de deux catégories d'instruments de régulation. La première est une approche par les prix, le péage urbain : plusieurs scénarios de péage urbain ont été élaborés puis évalués à l'aide des modèles précédents, de même que l'équité et, plus généralement, l'acceptabilité des politiques de péage. La deuxième catégorie d'instruments relève d'une approche par les quantités, les permis transférables appliqués dans le secteur des transports.
Les perspectives de recherche que je présente comportent deux axes, l'un autour des politiques innovantes de régulation de la demande, au sujet des quotas transférables dans le secteur des transports, l'autre relatif à la simulation de la ville comme système complexe, sur la base d'une modélisation multi-agents.
Elessa, Etuman Dipita Arthur. "Analyse des impacts des politiques énergétiques et de déplacements urbains sur la pollution de l’air : modélisation intégrée pour un espace urbain soutenable". Thesis, Paris Est, 2017. http://www.theses.fr/2017PESC1248/document.
Pełny tekst źródłaAir pollution is a major environmental and social problem and, at the same time, it is a complex problem that poses multiple challenges in terms of management and mitigation of air pollutants. Air pollutants are emitted by anthropogenic and natural sources. They can be either emitted directly (primary pollutants) or formed in the atmosphere (secondary pollutants). Their impacts on health, ecosystems, the urban texture and the climate are proven. Effective action to reduce the impacts of air pollution requires a good understanding of its causes, how pollutants are transported and transformed in the atmosphere and their impact on humans, ecosystems, climate, society, the economy and buildings. Today, policies and development plans aim to make cities sustainable which involves taking into account the internal interactions that make the city a complex system. It is necessary to consider the determinants of air quality. Modeling is one of the most important tools for decision support. There is currently little modeling work integrating several disciplinary fields in terms of air quality. This research aims to develop an innovative approach to the modeling of air quality by integrating social, economic and transportation logistics
Tchuinkam, Noukague Gustave. "Automatisation des fonctions documentaires et aide à la gestion des litiges dans le transport maritime de marchandises : essai d'adaptabilité de l'approche objet à la modélisation des connaissances juridiques". Montpellier 1, 1998. http://www.theses.fr/1998MON10028.
Pełny tekst źródłaLo, Feudo Fausto. "Un scénario TOD pour la région Nord-Pas-de-Calais : enseignements d'une modélisation intégrée transport-usage du sol". Thesis, Lille 1, 2014. http://www.theses.fr/2014LIL10129/document.
Pełny tekst źródłaThis thesis discuss the theme of integration and articulation between urban and transportation planning, with the aim of evaluate and studyi the sense and potentialities of the application of a Regional Plan for Transit Oriented Development (TOD) in Nord-Pas-de-Calais. In this regard we have chosen to use the tool of land use and transport integrated modeling (LUTI), and in particular the integrated simulation software Tranus, to implement a model which could answer to several research questions.We propose in this paper an integrated, inclusive and interactive perspective about problems and issues concerning land-use and transport policies at a regional level. A multidisciplinary and multi-scalar approach, following the principles of interdependence between all different elements of the territory, which is found in the concept of "networked city" of Dupuy. The aim is to address the themes of mobility and transport, according to a new paradigm, based on the concepts of accessibility, connectivity and multimodality and therefore according to the idea of an urbanism and a development oriented to transit and non-motorized transport, rather than car-oriented. The thesis is part of a phd research in urban and transportation planning, held at the University of Science and Technology of Lille 1, through a joint supervision between the Laboratoire Ville MObilité et Transport (LVMT - IFSTTAR) and the University of Calabria (Italy) and a scientific collaboration with Venezuelan engineering firm Modelistica
Abdallah, Charbel. "Evaluation des émissions et de la modélisation de la qualité de l'air sur Beyrouth et le Liban". Electronic Thesis or Diss., Paris Est, 2016. http://www.theses.fr/2016PESC1080.
Pełny tekst źródłaBecause of health and environmental problems related to air pollution in Lebanon, the number of studies investigating this matter has increased over the years to ensure a proper understanding of the situation, including measurements of air quality, studies on pollutant emissions and modeling of atmospheric concentrations using the chemistry transport model (CTM) WRF/Polyphemus. To model air quality in Lebanon, previous studies have identified several difficulties including: an overestimation of ozone concentrations by a factor of 2 in the modeling results of WRF/Polyphemus during summer 2012, a local VOC emission profile from road transport that is different from those found in developed countries. Consequently, the objectives of this thesis are: to improve the performance of Polyphemus over Lebanon by improving the boundary conditions of the simulation of, to evaluate the model for the year 2014 using new observations provided by the national air quality monitoring network, to measure emission factors from road transport in a tunnel in Beirut and compare those data to those observed in developed countries. To improve the performance of the CTM over Lebanon, this thesis compares the concentrations simulated with two different emission inventories and with different methods of estimating boundary conditions. For emissions, two inventories are compared: one that was recently set up specifically for Lebanon, and a global inventory, called EDGAR-HTAP, which combines measured emissions for developed countries and modelled emissions for the remaining countries Even though EDGAR-HTAP is commonly used in global air-quality models, significant differences in the estimation and the spatial distribution of the emissions are identified compared to the inventory specifically developed for Lebanon. In the simulations of the previous studies over Lebanon, boundary conditions were estimated using global simulations from the model MOZART-4. A regional domain over Middle East is introduced into the modeling chain to cushion the change in the horizontal resolution between the global model (≥ 1°) and the Lebanon domain (0.055°). The results from this change showed a significant improvement in the model performance over Lebanon, especially for ozone. This new modeling configuration (nested domains, Middle East and Lebanon is then used to model the year 2014 and it is evaluated using the observations provided by the national air quality monitoring network. For air-quality pollutants, the model performance is satisfactory, as using published criteria. However, weather modeling (Wind speed and Direction) should be improved, and we should take into account the impact on emissions of the demographic changes between the year for which inventory was designed (2011) and the modeled year (2014) due to the population displacement induced by the Syrian war.Concerning emission factors (EF) of road transport, we performed a measurement campaign at the Salim Slam tunnel in Beirut in 2014. The emission factors for the different pollutants (CO, NOx, PM2.5, VOC) were measured for the average traffic. Compared to other studies, the local EF are higher than those measured in developed countries even though they tend to be reduced, as a result of the changes in the fleet characteristics, compared to the values measured back in 2000
Elayeb, Mustafa. "Modélisation à l'échelle microscopique de transports avec réaction en milieu poreux : combustion en lit fixe". Poitiers, 2008. http://theses.edel.univ-poitiers.fr/theses/2008/Elayeb-Mustafa/2008-Elayeb-Mustafa-These.pdf.
Pełny tekst źródłaCombustion in porous media is addressed by means of direct, detailed numerical simulations, on the microscale, in an extension of the work of Debenest (2003) where the main improvements are related to the chemical model. More specifically, fixed bed combustion of solid particles is considered, with application to the burning of oil shales. The transport processes (convection, diffusion, conduction) and the chemical reactions are explicitely described on the pore scale, which allows to account for their local couplings and to identify the small-scale phenomena which control the global behaviors. The simulations are conducted mainly in two two-dimensional configurations, a stratified medium and a network of cylinders. The effect of pyrolytic reactions (kerogen cracking and calcination of the carbonates) are examined, as well as the oxydative processes, with a chemical scheme involving four species and up to four reactions. A phenomenological typology is established, which features for instance two main regimes, with or without a flamme in the pore space. Ranges of functioning modes are identified, according to the operating parameters. Their trends can be rationalized by theoretical considerations, and it is shown that different situations may require different formulations in a macroscopic description
Wester, Lea. "Transports collectifs et initiative individuelle : approche des transports collectifs artisanaux par l'auto-organisation et les systèmes multi-agents". Thesis, Aix-Marseille, 2018. http://www.theses.fr/2018AIXM0096.
Pełny tekst źródłaSeveral metropolises have not any centralized collective transport system, neither private nor public. Alternative solutions appeared, their caracteristics are principally that the ownership is spread out and the vehicle crew is self-directed. The mode of organization of these transports allows them to adapt dynamically to the demand.We propose to analyse the caracteristics of these systems by means of multi-agents modeling and self-organization theory. Using several models, we show how structures and dynamics of these systems are linked to individual strategies and urban structure.Through the question of adaptability of collective transport, small-scale transports led to concern about urban dimensions of collective mobility and flexibilisation of transport services
Audard, Frédéric. "Modélisation de la mobilité, la génération de trafic à l’échelle régionale". Besançon, 2006. http://www.theses.fr/2006BESA1022.
Pełny tekst źródłaPublic transport management is currently going through important changes, passing from one scale to another: decentralizing from the national level and extending at the local level. The range of transport management powers of the French administrative regions have widened, thus creating new management problems. Within the context of these new questions, our research proposes management solutions which take into account both the continual evolution of daily mobility and the new scales of transport management. More specifically, we considered a specific stage often neglected in geographical approaches to the suject. This stage called traffic generation consists in modelling the process of choice at the point origin of an individual journey. So far, the way that these questions have been treated using transport economy methods has obscured an important stage in the conception of traffic generation, the geographical stage. This stage relates to the zoning of the study area which constrains trip generation. We propose here to carry out the complete modelling of the traffic generation stage in the Franche-Comté region. This includes the understanding and the delimitation of our study area. Other results are the creation of a relevant zoning system in relation to management issues, in order to produce a final assessment of trip generation for the zoning system
Yirci, Murat. "Arrangements 2D pour la Cartographie de l’Espace Public et des Transports". Thesis, Paris Est, 2016. http://www.theses.fr/2016PESC1075/document.
Pełny tekst źródłaThis thesis addresses easy and effective development of mapping and transportation applications which especially focuses on the generation of pedestrian networks for applications like navigation, itinerary calculation, accessibility analysis and urban planning. In order to achieve this goal, we proposed a two layered data model which encodes the public space into a hierarchy of semantic geospatial objects. At the lower level, the 2D geometry of the geospatial objects are captured using a planar partition which is represented as a topological 2D arrangement. This representation of a planar partition allows efficient and effective geometry processing and easy maintenance and validation throughout the editions when the geometry or topology of an object is modified. At the upper layer, the semantic and thematic aspects of geospatial objects are modelled and managed. The hierarchy between these objects is maintained using a directed acyclic graph (DAG) in which the leaf nodes correspond to the geometric primitives of the 2D arrangement and the higher level nodes represent the aggregated semantic geospatial objects at different levels. We integrated the proposed data model into our GIS framework called StreetMaker together with a set of generic algorithms and basic GIS capabilities. This framework is then rich enough to generate pedestrian network graphs automatically. In fact, within an accessibility analysis project, the full proposed pipeline was successfully used on two sites to produce pedestrian network graphs from various types of input data: existing GIS vector maps, semi-automatically created vector data and vector objects extracted from Mobile Mapping lidar point clouds.While modelling 2D ground surfaces may be sufficient for 2D GIS applications, 3D GIS applications require 3D models of the environment. 3D modelling is a very broad topic but as a first step to such 3D models, we focused on the semi-automatic modelling of objects which can be modelled or approximated by generalized cylinders (such as poles, lampposts, tree trunks, etc.) from single images. The developed methods and techniques are presented and discussed
Mahaman, Moutari Mahaman Salissou. "Modélisation mathématique et numérique du trafic automobile". Nice, 2007. http://www.theses.fr/2007NICE4088.
Pełny tekst źródłaIn order to simulate in a relevant way vehicular traffic on large road networks, an essential ingredient is using theoretical tools which allow for an adequate modelling of each component of the network. To achieve this goal, several modelling methods exist to date. However, due to some additional constraints, in particular those related to the development of the road networks infrastructures and the increasing concentration of traffic, the investigation of new modelling tools is necessary. In this work, we have introduced some methods and models, which enable a relevant description of the traffic on road networks, by taking into account its specificity through some particular components of the network such as intersections, highway on and off ramps, toll stations, etc…. The presented approaches are expected to be theoretically rigorous, numerically reliable, and computationally efficient. The first approach we have proposed concerns macroscopic models. It is based on the resolution of the Riemann problem whereas the flux at the junction is optimized. Thereafter we have extended this approach to macroscopic multiclass models. The second approach studied in this work is the hybrid modelling. First, we have proposed a hybrid model based on the classical Eulerian-Lagrangian coupling of the Aw & Rascle second order macroscopic model and a class of microscopic models. In a such hybrid model, the interfaces between the coupled models are fixed in eulerian coordinates. Thereby, the interfaces’ functioning is somehow complex and tedious to work out. In order to circumvent this problem, we have proposed a fully lagrangian coupling approach. The novelty of this new hybrid approach is that the interfaces are moving in lagrangian coordinates. This particular property makes the model much simpler than in the previous case and leads to a rigorous and easy computational model. Finally we have proposed a model describing the formation and evolution of traffic jams. This model is derived from the Aw & Rascle second order macroscopic model and based on a realistic formulation of clusters dynamics. We have analysed the solutions to the associated Riemann problem and we have proved the existence of solutions for this model
Delteil, Jacques. "Modélisation et exploitation de réseaux linéaires pour la simulation en temps réel". Toulouse 3, 1996. http://www.theses.fr/1996TOU30105.
Pełny tekst źródłaBencheikh, Ghizlane. "Problèmes de transport : modélisation et résolution par les métaheuristiques". Le Havre, 2009. http://www.theses.fr/2009LEHA0022.
Pełny tekst źródłaIn this thesis, we have considered two different scheduling problems : Scheduling Aircraft Landing and Professional Staff Transportation Problem. For the aircraft landing problem, we have proposed a mathematical formulation of the problem and a job shop formulation of the problem. Three resolution methods are given. The first one is a hybrid method combining Genetic Algorithm and Ant colony Optimization. The Second method is a combination of a genetic algorithm and tabu search. The last resolution method consisted to apply ant colony algorithm combined with a local search heuristic, this algorithm deal with the dynamic case where there is a cancellation of a flight or a runway closure. The Professional Staff Transportation Problem consists to build the routing of a limited fleet of vehicles in charge of transporting the staff of one or several companies (on their demand). The goal is to minimize the total cost of transport, and maximising the level of service offered to users. The quality of service is expressed in our work in terms of waiting time and ride time of users. After we have shown a mathematical formulation, we gave a resolution method of the problem based on ant colony optimization. Finally, we solved the problem by two population metaheuristics, namely, ant colony algorithm and genetic algorithm. The ant colony algorithm is based on the "cluster first/rout second" method. Before presenting experimental results of the two algorithms, we have fixed their parameters by a factorial experimental design
Herrgott, David. "Modélisation et mise en perspective de la diversité du fonctionnement des transports ferroviaires conventionnés de voyageurs". Thesis, Strasbourg, 2015. http://www.theses.fr/2015STRAH011.
Pełny tekst źródłaThe current government’s legislation to restructure the rail sector defines the national rail system as a complex system composed of “all the human and material means implemented on the national rail network in order to ensure the management and delivery of transport services using it”. Within this framework, this thesis attempts to analyze in a necessarily interdisciplinary perspective the relationship between the different components of the rail system, in order to make it intelligible. It aims to contribute to understanding the railway system and its current issues, by completing this empirical based approach to modeling the public service obligations, which represent most of the traffic and publics funds on the French rail network
Le, Pollès Thierry. "Modélisation des champs diffus en acoustique architecturale par la théorie des transports : application au milieu urbain". Le Mans, 2003. http://cyberdoc.univ-lemans.fr/theses/2003/2003LEMA1016.pdf.
Pełny tekst źródłaThe aim of this work was to develop a new diffuse sound field model, taking into account diffusion, scattering, atmospheric and meteorological effects. . . After a state of art, the sound particle concept seemed rigorous to treat analytically this kind of phenomena. The application of this concept allowed to describe spatial and temporal sound energy evolution in terms of a transport equation similar to the free molecular flow equation. Boundary conditions were introduced in terms of local flux introducing surface reflection laws to take into account scattering effects. As an application, solutions were found in a narrow street with the help of asymptotic approaches. It was shown that in such propagation medium, the diffusion equation corresponds to the limit of the transport equation. Diffusion coefficients were then developed for several reflection laws. Confrontation of analytical solutions and Monte Carlo numerical simulations was then performed. A good agreement was found. Finally, analytical solutions were compared to experimental data obtained during experiments in a street of Nantes. This comparaison showed a great coherence of the model and interesting prospects for the future
Benmansour, Senouci. "Modélisation de l’activité routière en vue de son intégration dans la chaine logistique". Le Havre, 2009. http://www.theses.fr/2009LEHA0026.
Pełny tekst źródłaThe work of this thesis contributes to use the Bond Graph (BG) approach to develop both simple and rigorous road traffic model, which extends a large road networks and easily adapted to the aimed analysis level. This model allows us to describe the global dynamic behavior of the traffic on road networks, by taking into account its specificity through all the network components, such as road sections, intersections, highway on and off ramps, toll stations, etc… Moreover, it makes it possible to focus on the behaviour of individual vehicles and their interactions at certain locations on the network requiring precision. This homogeneous description of the traffic in any point of the network and at any moment offers a greater simplicity and a great unity in comparison with the existing traffic models. Given the characteristics of this road network BG model, significant contributions can be brought to control and supervise the traffic. To extend this BG traffic model to study the dynamic behavior of physical flow on supply chain, we have transposed the concepts developed for the traffic to the supply chain
Gashaw, Sosina Mengistu. "Modélisation de trafic routier hétérogène pour systèmes de transport intelligents". Thesis, Université Côte d'Azur (ComUE), 2018. http://www.theses.fr/2018AZUR4202/document.
Pełny tekst źródłaThis dissertation models and analyzes heterogeneous traffic flow, with a particular focus on mixed traffic flow consisting of cars and two-wheelers. The increase in traffic congestion induces commuters to switch to powered two wheelers (PTWs), i.e. motorcycle, mopeds and scooters, because of their high maneuverability and space efficiency. The growth in number of PTWs, combined with their unique mobility features, results in complex traffic characteristics which are difficult to recreate with the existing modeling approaches. We develop an analytical model that can accurately reproduce the traffic features in a mixed flow of cars and PTWs. The traffic stream is decomposed into two vehicle classes, PTWs and cars. The fundamental properties are derived by employing a porous flow approach. It is assumed that the speed of a vehicle class is dictated by the physical and motion properties of the vehicle class, and the distribution of free spaces on the road. We propose an approximation method to derive the free-space distribution. In order to explore broader aspects of the traffic flow characteristics, notably required by intelligent transport system (ITS) applications, we formulate the model in the Lagrangian and the Eulerian frameworks. Further, we provide a numerical method for the discretization of the mathematical model. We analyze the flow characteristics of mixed PTWs and cars traffic and identify important properties, which give insights for future ITS solutions and traffic policy makers. The applicability of the model for different ITS applications is illustrated. Finally, the developed model is validated using a microsimulation tool
Bosquet, Romain. "Modélisation énergétique et identification des trains pour l’écoconception des lignes ferroviaires à grande vitesse". Nantes, 2015. https://archive.bu.univ-nantes.fr/pollux/show/show?id=94948608-f978-4d64-b9c7-b10b532a58bd.
Pełny tekst źródłaThe current transport system is not sustainable because of its high consumption of finite resources (mainly oil) and its impact on the environment (air quality, global warming, etc. ). In this context, rail has several advantages: lower consumption and emissions than road and air modes, larger passenger flow, etc. That is why, many rail infrastructures are planned in the world. Today, the impact of energy is not taken into account during the project design. The goal of this thesis is to include an energy criterion in the design phase, this is called ecodesign. For this, it is necessary to assess the energy cost of traffic. This is the focus of this thesis. A model of energy consumption of a train depending on the track profile is proposed. It is based on a mechanical model and an electric model. The parameters of this model are identified and the model is validated during experiments on the Rhin-Rhône high-speed line. Robotic techniques are used. Finally, the consumption of traffic is estimated by coupling this consumption model with a driver model. Proposed applications are various: evaluation of design rules concerning declivity, energy evaluation of a traffic flow and optimization of routes. An operational application is proposed by use of this work to the energy consumption of two project variants of the Montpellier-Perpignan high-speed line project. Mots clés train, énergie, modélisation, tracé, infrastructure, identification, optimisation, ligne à grande vitesse. Key Words
Adamiak-Forte, Adrien. "Infrastructures et Territoires : une contribution à la modélisation des interactions entre transports et télécommunications en Economie géographique". Phd thesis, Université Jean Monnet - Saint-Etienne, 2010. http://tel.archives-ouvertes.fr/tel-00665934.
Pełny tekst źródłaCayla, Jean-Michel. "Les ménages sous la contrainte carbone : exercice de modélisation prospective des secteurs résidentiel et transports avec TIMES". Phd thesis, École Nationale Supérieure des Mines de Paris, 2011. http://pastel.archives-ouvertes.fr/pastel-00608619.
Pełny tekst źródłaKacem, Abbes. "Auralisation des transports ferroviaires en milieu urbain". Thesis, Université Grenoble Alpes (ComUE), 2019. http://www.theses.fr/2019GREAT049.
Pełny tekst źródłaRailway transportation represents an important source of noise pollution in urban areas. Both the development of new infrastructures and the increase in traffic raise the number of people impacted. As a result, reduction of railway traffic noise remains an active research field. The work carried out on the subject has been mainly focused on the estimation of sound levels. Theoretical and empirical models have been proposed to accurately predict railway noise levels. However, averaged sound pressure levels may be difficult to translate in terms of perceived noise annoyance, due to the complexity of the involved phenomena. One way to assess perceived noise annoyance is to synthesize and render the time domain pressure signal perceived by a listener. Noise annoyance is then evaluated perceptually through listening tests. This approach is called auralization.The goal of this thesis is to develop auralization methods for acoustic emissions from railway vehicles in urban environments. Railway noise is radiated from many individual sources. In urban areas, the railway noise mainly consists of rolling and traction noise. This thesis focuses specifically on the audio synthesis of these sources.In order to assess different types of wheels and rails, the auralization method of the rolling noise is based on a physical model whose parameters may be varied. In this approach, the excitation of the wheel/rail system is modeled in the time domain. Three sound synthesis modules are proposed for the acoustic emission signals of the rail, wheel and sleepers. Each module accounts for the excitation force of the wheel/rail system. Comparisons of simulated pass-by noise levels with measured data show a good agreement with differences smaller than 2 dB(A) in terms of A-weighted sound pressure levels. The approach is also evaluated trough listening tests. It is shown that when properly configured, the proposed model yields very realistic sounds.Noise from the traction system components is auralized using a granular synthesis technique. The technique, previously developed for road traffic engine noise, is adapted to railway vehicle noise. It is shown to accurately synthesize the acoustic emissions of these components
Teypaz, Nicolas. "Contribution à la résolution de problèmes de transport en commun et de fret : modélisation et algorithmes". Grenoble INPG, 2008. http://www.theses.fr/2008INPG0014.
Pełny tekst źródłaLn this thesis, two problems in the transport sector were studied. The first application is included in the process of transit system development. The transit network design problem has been studied according to the criteria most relevant to optimize. An approach is proposed to deal with the multi-objective problems. A Tabu Search engine adapted to our approach has been developed: the proposed algorithm enables to build a solution preserving the same trade-off between the criteria as the initial solution. The second application consists in determining of a set of plannings of freight transport that maximizes the carrier profit. But the complex structure of the problem, our resolution scheme is based on decomposition into three sub-problems: construction of the network, construction of the vehicle plannings and filling with commodities. From this decomposition, we have developed two algorithms: one permits the transshipment operations, the other does not. The algorithm without transshipment is very robust and very fast
Briant, Régis. "Modélisation multi échelles de l'impact du trafic routier sur la qualité de l'air". Electronic Thesis or Diss., Paris Est, 2012. http://www.theses.fr/2012PEST1115.
Pełny tekst źródłaRoadway traffic contributes to atmospheric pollution near roads, with pollutants such as nitrogen dioxide (NO2), particles (PM) along with some volatile organic compounds (VOC), as well as at larger spatial scales (urban and regional background pollution) with pollutants formed in the atmosphere such as ozone (O3) and the secondary fraction of PM. Because of interactions between local and background pollutants, it is desirable to combine into a single computational tool, regional and local scale models. This multi-scale modeling method has been widely used to simulate the impact of chimney emissions (point sources) with a sub-grid treatment of plume or puff models instead within a 3-dimensional Eulerian model. However, such a method is not applicable to a road network because of the prohibitive computations associated with the line source discretization into a set of point sources. Thus, a new multi-scale modeling method was developed, which treats the plumes emitted from line sources as sub-grid components of an Eulerian model. First, an improved formulation of a Gaussian plume model for line sources was developed. This new model was then subject to a detailed evaluation with near roadway measurements along with other Gaussian models. The incorporation of the Gaussian plume model into an Eulerian model (Polair3D) was implemented as part of the modeling platform Polyphemus. The performance (computational effectiveness and precision) of the new multi-scale model (Plume-in-Grid) was evaluated and compared to those of a stand-alone Gaussian and Eulerian models. The multi-scale model treats nitrogen oxide (NOx) chemistry along with major VOC. The multi-scale treatment has an important effect on the concentration of some pollutants in terms of local and urban background pollution
Baptiste, Hervé. "Interactions entre le système de transport et les systèmes de villes : perspective historique pour une modélisation dynamique spatialisée". Tours, 1999. http://www.theses.fr/1999TOUR1801.
Pełny tekst źródłaChausi, Benoît. "Modélisation des phénomènes de transports en milieu déformable diphasique dont une phase est binaire : Application à la DII". Pau, 2000. http://www.theses.fr/2000PAUU3024.
Pełny tekst źródłaZhang, Qiao. "Contribution à l'ordonnancement d'ateliers avec ressources de transports". Phd thesis, Université de Technologie de Belfort-Montbeliard, 2012. http://tel.archives-ouvertes.fr/tel-00909927.
Pełny tekst źródłaSiour, Guillaume. "Modélisation et évaluation de l’impact multi-échelles des mégapoles européennes". Thesis, Paris Est, 2012. http://www.theses.fr/2012PEST1034/document.
Pełny tekst źródłaThe important increase in worldwide population identified during the last century led to a human migration toward urban areas. As a consequence, 50 high populated areas called megacities, reaching more than 7 millions of people, appeared in the last decades. This huge increase happened so fast that existing infrastructures (such as roads network, public transport) is not suitable anymore. Taking into account environmental issues (air quality, supply and waste management) in this context is then a real challenge. In the meantime, observations and numerical models highlight the need to deal with local pollution in megacities as well as climate policy, through the consideration of pollutants transfer from local scale to global scale. The increase of ozone background in Europe, which also is a climate issue, could depend of the increase of the megacities emissions in the north hemisphere, due to the economical development (Monks et al., 2009).What do we know of the megacities real impact on air quality? Scientific studies aiming to understand the key parameters of oxidizing pollution have mainly focus on the local and regional scales. Interactions between megacities and global scale have been the subject of many modelling studies (Wild et Akimoto, 2001; Stohl et al., 2002; Lawrence et al., 2003, 2007). However, there are still few works concerning interactions between megacities and their continental environment. My thesis works were then aiming at identifying theses impacts using eulerian modelling. My main interrogations concerned the nature, the magnitude, the scope, direct and indirect impact, and finally the pollutants exported by European megacities flux variations. In addition, I also investigated the nature of these high emission areas, through the sensitivity of the urban structure on their impacts (compact or spread cities). New tools developments in the model (flux calculation, new chemical scheme, implementation of an upgraded tool dedicated to scales interaction) were necessary to answer the problematic
Bougna, Tchofo Emmanuel. "Analyse et modélisation de l'impact de la libéralisation sur les performances ferroviaires". Thesis, Lyon, 2017. http://www.theses.fr/2017LYSE2032/document.
Pełny tekst źródłaAfter having accompanied the industrial revolution in the 19th century, rail transport difficultly adapt to the challenges launched by the road since a hundred years. Nowadays, European rail transport suffers from competition from the road, both for travellers and cargo. Since the beginning of the 20th century, the role of the railways in the goods and passengers transport has been declining. In the countries of the European Union, it now does ensure only 6% of passenger transport and 16% of goods transport. The European rail transport renewal is also marked by the development of the high-speed train. Total passenger "high speed" traffic is 15 billion passenger-km in 1990 against 111 billion passenger-km in 2014, that is an overall growth of 740%. The share of total passenger "high speed" traffic has increased from 4% in 1990 to 25% in 2014.The obvious observation is that, since the beginning of the 1990s, the railways have lost market share and therefore required growing subsidies.The need to improve this situation led to imagine a wide range of possibilities for action by national and European public authorities. Since the beginning of the 1990s, the European Commission is engaged in a vast reform aiming at the construction of an integrated railway area.In a context of European rail slump, we want to appreciate the performance of the railways in order to identify the main factors that will avoid the decline. We start from the idea that railways must be efficient in terms of production and commercialization of services.Each of the four chapters of this thesis uses various methods to contribute to the growing field of the rail transport.The first chapter uses the partial measures of productivity indicators to evaluate the performance of a panel of four European railway companies, the DB in Germany, SNCF in France, the RENFE in Spain and FS in Italy, observed between 1990 and 2012. Our aim here is twofold, to take stock of the current situation and reveal the path of major European rail companies on a period starting a little before the railway reforms initiated by the European Commission. These indicators help us to evaluate four areas of performance: productive performance, business performance, economic performance and financial performance. It is for us the opportunity to evaluate the efficiency of the directive 91-440 of 29 July 1991 relating to the development of Community railways, directive that recommends to promote the independence of management of railway companies, as well as their financial clean-up, especially their deleveraging. The second chapter shows the theoretical framework of technical efficiency, by a review of the theoretical foundations and by presenting the methodology of the borders. To complete this analysis, we propose a review of non-exhaustive literature of empirical studies on the evaluation of the performance of the railways. The third chapter suggests empirical contributions to the measurement of the performance of the railways. It is for us the opportunity to evaluate, compare and explain the differences in performance of some countries of the European union. Four performance indicators have caught our attention: productive efficiency, trade efficiency, technical efficiency and the variation of the total factor productivity. To this end, we simultaneously estimated three parametric and stochastic borders, namely, a production-oriented input border, a border of consumption and a border of technical efficiency-oriented input