Dissertations / Theses on the topic 'Contrôle du trafic'
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Pisarski, Dominik. "Contrôle d'accès collaboratif : application à la rocade sud de Grenoble." Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENT040/document.
Full textThe thesis presents the results of research on distributed and coordinated control method for freeway ramp metering. The freeway traffic is represented by the Cell-Transmission Model. The primary control objective is to provide a uniform distribution of vehicle densities over freeway links. Density balancing is a new traffic objective which can potentially reduce the number and intensity of acceleration and deceleration events and therefore, it can make a travel more safety and comfortable while decreasing fuel consumption and emissions. In addition, the objective takes into account standard traffic metrics like Total Travel Distance and Total Travel Spent. For the controller, a distributed modular architecture is assumed. It enables to compute the optimal decisions by using only local state information and some supplementary information arriving from the neighbouring controllers.The contributing part begins with the analysis on equilibrium sets of the Cell-Transmission Model. The goal of this study is to derive the conditions that assure the existence and the uniqueness of the balanced equilibrium states. The next step is to find a set of inputs such that the resulting equilibrium state is balanced. In the set of balanced equilibria, we are interested in the selection of the point that maximizes the Total Travel Distance. In the sequel, the implementation aspects and limitations of the proposed method are discussed. Finally, several case studies are presented to support the analysis results and to examine the effectiveness of the proposed method.The major part of the thesis aims on a design of an optimal controller for balancing the traffic density. The optimization is performed in a distributed manner. By using controllability properties, the set of subsystems to be controlled by local ramp meters are identified. The optimization problem is then formulated as a non-cooperative Nash game. The game is solved by decomposing it into a set of two-players hierarchical and competitive games. The process of optimization employs the communication channels matching the switching structure of system interconnectivity. The alternative approach of balancing employs the theory of multi-agent systems. Each of the controllers is provided with a feedback structure assuring that the states within its local subsystem achieve common values by evaluating consensus protocols. Under these structures, an optimal control problem to minimize the Total Travel Spent is formulated. The distributed controller based on the Nash game is validated via Aimsun micro-simulations. The testing scenario involves the traffic data collected from the south ring of Grenoble
Debernard, Serge. "Contribution à la répartition dynamique de tâches entre opérateur et système automatisé : application au contrôle du trafic aérien." Valenciennes, 1993. https://ged.uphf.fr/nuxeo/site/esupversions/455a1b3c-57c3-4994-98ff-5dec24c35a2d.
Full textBoudes, Nicole. "L'anticipation dans le contrôle des environnements dynamiques : le cas du contrôle du trafic aérien." Toulouse 2, 1997. http://www.theses.fr/1997TOU20057.
Full textThis cognitive ergonomics research is part of an on-going effort to analyze time management in dynamic environments, which is an evolving domain. Its objective is to construct a cognitive model of anticipation in air traffic control, which could be used for decision support system design in this situation. Numerous studies have previously emphasized, on one hand the need for operators to anticipate the future development of the controlled environment so as to avoid the development of disturbances, and on the other hand, the complexity and the demand associated with this activity. The anticipation activity implies temporal information processing and concerns three dimensions: spontaneous evolutions, effects of actions, evolutions related to the team members' activity. In air traffic control, we analyzed the anticipation with interviews and written data gathered in a dynamic and realistic simulated control situation. We showed that anticipation depends on filtering strategies, which leads to some variations in the content of the anticipation range, according to the task objectives. Concerning the accuracy of the estimations, we studied the time horizon effects on the possibility for operators to anticipate the future positions of certain aircraft. Results showed some biases that were analyzed in relation to the operator's objectives and the characteristics of the task. The experimental study expressed the importance of the context in anticipation and its links with the whole set of cognitive activities. On the applied aspect, we got a better understanding of anticipation, which is a central activity in air traffic control, and that allowed us to consider the possibilities to use this knowledge in decision support system design
Harivelo, Fanilo. "Contrôle de trafic pour service privilégié sur réseaux sans fil." La Réunion, 2006. http://www.theses.fr/2006LARE0020.
Full textDesigned as an extention to wired local area networks, wireless local area networks lead to new potentials such as ubiquity. Wireless channels characteristics as well as mobility of terminais complexify thé support of Quaîity of Service in thèse networks. This disser¬tation concentrâtes on thé support of service differentiation in IEEE 802. 11-based ad hoc networks. It begins wifch thé study of thé support of service differentiation in a single hop network. The idea consists in controlling thé traffic at thé IP level according to thé net¬work state. Two types of implementation are studied: computation of thé network state by means of message exchange and estimation of thé network state by local measurements. Then, a solution to channel acccss unfairness issues is proposed. Indeed, under certain con¬figurations, channel access does not dépend solely on thé traffic load but also on thé relative position of thé nodes. The proposed solution consists in thé propagation of thé receiving state of nodes and in thé synchronization of thé beginning of 802. 11 access opération. Fi-nally, in ordcr to simphfy resources management and to reduce co-channel interférences, a hierarchical organization of thé network is proposed. It is based on a topology control or clustcring sclieme and a, channel assignaient mechanism
Gianazza, David. "Optimisation des flux de trafic aérien." Phd thesis, Toulouse, INPT, 2004. http://oatao.univ-toulouse.fr/7377/1/gianazza.pdf.
Full textGianazza, David. "Optimisation des flux de trafic aérien." Phd thesis, Toulouse, INPT, 2004. http://ethesis.inp-toulouse.fr/archive/00000075/.
Full textMa, Ji. "Optimisation du trafic aérien dans de grands aéroports." Thesis, Toulouse 3, 2019. http://www.theses.fr/2019TOU30052.
Full textThe air traffic growth induces congestion and flight delays both at the airports and in the surrounding airspaces. In fact, the airports are limited in terms of capacity and represent the major bottlenecks in the air traffic management system. Efficient planning and control are critical to enhance the airport operation efficiency and to reduce flight delays. In prior research, several sub-problems associated with airport operations have already been discussed separately, such as runway scheduling, taxiway scheduling, terminal airspace management, etc. However, these operations are closely related and can affect each other. This motivates the development of an integrated optimization approach for managing air traffic at airport and in the surrounding airspace. In this thesis, we suggest a two-level optimization approach which works on both the macroscopic and the microscopic levels. Following the prediction horizon of different problems, we consider first a long term horizon with an abstract network of airport and TMA. Then, we consider a shorter horizon with a detailed network of airport components. In the first part of the thesis, we focus on the integrated optimization of airport operation problem and terminal airspace management problem at a macroscopic level. The airside is modeled as an abstract network: terminal, taxi network, and runway are seen as specific resources with a defined maximum capacity, and the TMA is modeled by a predefined route network structure. This level of abstraction aims at identifying the airport congestion situations. We develop an optimization model to minimize flight delays, resolve airspace conflicts, and mitigate airport congestions by controlling speed, arrival and departure times, and assigned runway, while keeping various operational constraints. An adapted simulated annealing (SA) metaheuristic combined with a time decomposition approach is proposed to solve the corresponding problem. Computational experiments performed on case studies of Paris Charles De-Gaulle airport show potential improvements on airport congestion mitigation and flight delay reduction. The second part of the thesis deals with the airport runway and taxiway scheduling problem at a microscopic level. In this part, we represent the airport (gate, taxiway, runway) with a detailed surface node-link network, and we consider individual aircraft trajectories based on this graph. We aim at resolving the ground conflicts among aircraft, assigning the pushback times, the taxi speeds and the positions (runway threshold or holding point) and the holding times. The optimization model is designed to reduce runway queue length and minimize flight delays as well as taxi times with respect to safety concerns in surface traffic operations. A comparison with regard to baseline scenarios of the microscopic optimization benefits is presented for two major airports: Paris Charles De-Gaulle (CDG) airport and Charlotte Douglas International airport (CLT). Important gain in taxi time savings and runway queue length reduction are achieved, particularly at CLT since it is more prone to congestion
Ouafi, Rachid. "Analyse et contrôle des réseaux de trafic urbain par la méthode de Frank-Wolfe." Paris 6, 1988. http://www.theses.fr/1988PA066453.
Full textAlshaer, Hamada. "Gestion et contrôle de trafic prioritaire dans les réseaux IP multiservices." Paris 6, 2005. http://www.theses.fr/2005PA066564.
Full textWigetman, Robert. "Vers la conception du système Sieel : un tuteur intelligent pour le contrôle aérien." Toulouse 3, 1994. http://www.theses.fr/1994TOU30258.
Full textGotteland, Jean-Baptiste. "Optimisation du trafic au sol sur les grands aéroports." Phd thesis, Toulouse, INPT, 2004. http://oatao.univ-toulouse.fr/7378/1/gotteland.pdf.
Full textBosc, Jean-François. "Techniques d'évitement réactif et simulation du trafic aérien." Toulouse, INPT, 1997. http://www.theses.fr/1997INPT103H.
Full textZitoune, Lynda. "Approche automatique de l'ingénierie de trafic Internet." Paris 11, 2006. http://www.theses.fr/2006PA112138.
Full textThe integration of multimedia applications within telecommunications services has stressed the need for both Quality of Service architectures and effective traffic control mechanisms. To ensure performance guarantees in terms of loss, delay and jitter are a critical problem ofthe next generation networks. It involves a reactive control policy which adapts the source rate to the network state variations. In this thesis, we introduce two new reactive mechanisms for controlling multimedia flows over a QoS architecture. They act as a closed loop to control the sources bit-rates according to the dynamic variations of the network. The regulation consists in limiting the traffic sources andrespecting the time and loss constraints. The objective of the present work is twofold. We first propose solutions for resource allocation and service guarantees in future networks. Secondly we show the contribution of the reactive control and the dynamic regulation using purely control theoretic approaches which stabilize the network and avoid undesirable oscillations for the transmission of critical flows, contrary to the currently used end-to-end control to avoid the congestion
Ramamonjisoa, David. "Architecture de copilotage et de contrôle d'exécution basée sur un système expert temps réel." Compiègne, 1993. http://www.theses.fr/1993COMP574S.
Full textCrevits, Igor. "Répartition dynamique de taches dans les procédés complexes. Modélisation de la répartition anticipée : application au contrôle de trafic aérien." Valenciennes, 1996. https://ged.uphf.fr/nuxeo/site/esupversions/8e4a1e03-64eb-4e69-9a03-f26c175ea950.
Full textEscamilla, Núñez Héctor. "Contribution au guidage des avions en trafic à haute densité." Thesis, Toulouse 3, 2018. http://www.theses.fr/2018TOU30074/document.
Full textThis work is developed with the perspective of SESAR and Next-Gen projects, where new applications of Air Traffic Management (ATM) such as the Full 4D Management concept, are centered on Trajectory-Based Operations (TBO), deeply related with the extension of the flexibility in separation between aircraft, and hence, with the augmentation of air traffic capacity. Therefore, since a shift from fixed routes and Air Traffic Control (ATC) clearances to flexible trajectories is imminent, while relying on higher levels of onboard automation, the thesis hinges around topics that should enable or ease the transition from current systems to systems compliant with the new expectancies of Trajectory-Based Operations. The main axes of the manuscript can be summarized in three topics: 4D trajectory generation, 4D guidance, and mass estimation for trajectory optimization. Regarding the trajectory generation, the need of airspace users to plan their preferred route from an entry to an exit point of the airspace without being constrained by the existent configurations is considered. Thus, a particular solution for 4D smooth path generation from preexisting control points is explored. The method is based on Bezier curves, and is able to control the Euclidian distance between the given control points and the proposed trajectory. This is done by reshaping the path to remain within load factor limits, taking into account a tradeoff between path curvature and aircraft intended speed, representing a milestone in the road towards Trajectory-Based Operations. It is considered that accurate 4D guidance will improve safety by decreasing the occurrence of near mid-air collisions for planned conflict free 4D trajectories. In consequence, two autopilots and two guidance approaches are developed with the objective of diminishing the workload for air traffic controllers associated to a single flight. The backstepping and feedback linearization techniques are used for attitude control, while direct and indirect nonlinear inversion are adopted for guidance. Furthermore, the impact of inaccurate mass knowledge in trajectory guidance, with consequences in optimization, fuel consumption, and aircraft performance, has led to the implementation of an on-board aircraft mass estimation. The created approach is based on least squares, providing an initial mass estimation, and online computations of the current mass, both with enough accuracy to meet the objectives related to TBO. The methods proposed in this thesis are tested in a six degrees of freedom Matlab model with its parameters chosen similar to an aircraft type B737-200 or A320-200. The simulation is based on a full nonlinear modelling of transport aircraft dynamics under wind disturbances. Trained neural networks are used to obtain the aerodynamic coefficients corresponding the aircraft forces and moments
Jacquet, Denis. "Modélisation Macroscopique du Trafic et Contrôle des Lois de Conservation Non Linéaires Associées." Phd thesis, Grenoble INPG, 2006. http://tel.archives-ouvertes.fr/tel-00150434.
Full textLoyer, Nicolas. "Contrôle de AP-1 sur le trafic de E-Cadhérine chez Drosophila melanogaster." Thesis, Rennes 1, 2014. http://www.theses.fr/2014REN1S066/document.
Full textEukaryotic cells are compartmentalized in organelles. Lipidic and proteic exchanges between organelles and the plasma membrane are controlled by vesicular trafficking. In polarised cells such as epithelial cells, whose plasma membrane is divided into an apical and a basolateral pole separated by a junctional belt, appropriate targeting of proteins to appropriate poles relies on polarised sorting mechanisms controlling vesicular trafficking. In these cells, the clathrin adaptor complex AP-1 controls basolateral targeting and trafficking of the adhesion molecule E-Cadherin, a transmembrane adherens junctions protein. AP-1 is furthermore necessary for epithelial polarity maintenance in intestinal epithelial cells in the nematode C. elegans and mammals. I studied AP-1 functions in the model organism Drosophila melanogaster. I showed AP-1 also controls E-Cadherin trafficking in Drosophila but is not required for polarity maintenance in follicular cells, an epithelium surrounding the female germline cyst during oogenesis. Experiments in this tissue led me to discover a new E-Cadherin function in the germline cyst. Germline cyst cells are interconnected by cytoplasmic bridges stabilised after incomplete cytokinesis. I showed AP-1 mutant cyst cells were multinucleated due to a detachment of cytoplasmic bridges from the plasma membrane. This phenotype correlated with an E-Cadherin AP-1-Dependent targeting defect from recycling endosomes to the plasma membrane surrounding these bridges. E-Cadherin is necessary for their anchoring to the plasma membrane, a role that was hidden by ectopic compensatory expression of N-Cadherin in E-Cadherin mutants. This new role is mediated by E-Cadherin-Dependent organisation of membrane protrusions similar in aspect with and containing proteins of microvillosities present at the apical pole of epithelial cells
Valenti, Silvio. "La gestion du trafic P2P dans les réseaux modernes : mesure, identification et contrôle." Phd thesis, Télécom ParisTech, 2011. http://pastel.archives-ouvertes.fr/pastel-00645263.
Full textValenti, Silvio. "La gestion du trafic P2P dans les réseaux modernes : mesure, identification et contrôle." Phd thesis, Paris, Télécom ParisTech, 2011. https://pastel.hal.science/pastel-00645263.
Full textDue to the large diffusion of P2P applications and especially P2P live-streaming, P2P traffic occupies an extremely large portion of overall Internet traffic. In this context, this thesis proposes new instruments to measure, identify and control P2P traffic. Regarding traffic classification, since traditional techniques have a hard time identifying P2P traffic, we propose a new behavioral classifier, Abacus, tailored for P2P live-streaming. Our experiments prove that Abacus, though based on simple counts of packets and bytes exchanged by a host, represents a lightweight and accurate solution for identifying P2P applications. Second, since the huge volume of traffic obliges operators to employ either flow-level monitors (e. G. NetFlow) or packet sampling to cut down the amount of measurement data, we evaluate the impact of data reduction on traffic characterization and classification. We show that Abacus can be adapted to this kind of data, suffering only a minor loss in accuracy and statistical classification remains possible if training and validation data are sampled at the same rate, in spite of the distortion introduced by packet sampling. Finally, we study a new transport protocol for P2P traffic, LEDBAT (Low Extra Delay Background Transport Protocol), the congestion control algorithm of the official BitTorrent client. This delay-based algorithm aims to provide an efficient, lower-than-best-effort service. Though faithful to its goals, the original design of LEDBAT appears affected by a latecomer advantage: we identify the main cause of the unfairness and propose effectives correction that restore the fairness
Schanzenbächer, Florian. "Max-plus modeling of traffic on passenger railway lines with a junction : fundamental diagram and dynamic control." Thesis, Paris Est, 2020. http://www.theses.fr/2020PESC2098.
Full textThe aim of the doctoral thesis is to contribute on the developpement of real-time traffic control algorithms for mass transit railway systems with junctions, located in urban areas. The scientific ambition of the doctoral thesis is to develop a traffic model with a finer modelisation of the train-passengers interaction. The model will allow a more precise evaluation of the level of service offered to the passengers and of the decisions taken by the operator of the line. Basing on this modeling, we will develop a control algorithm (strategic/ tactical and operational) in order to enhance the service quality on the line. The objective of the Paris metro system operator, financing this thesis, is to have a ready-to-implement control system for a railway line with a junction
Lemoine, Marie-Pierre. "Coopération hommes-machines dans les procédés complexes : Modèles techniques et cognitifs pour le contrôle de trafic aérien." Valenciennes, 1998. https://ged.uphf.fr/nuxeo/site/esupversions/0821b192-7376-49d6-ba14-abc99ab0917a.
Full textSanogo, Cheick. "Modeling user impatience and its impact on performance in mobile networks." Thesis, Evry, Institut national des télécommunications, 2017. http://www.theses.fr/2017TELE0009/document.
Full textIn this thesis we study user impatience and quantify its impact on the performance of mobile networks in the presence of elastic user in which we develop two approximate expressions for the stationary distribution of the system: an aggregate one and a detailed one and show their closeness to the exact model. We study mobility of elastic user who may be impatient and quantify its impact on system performance in mobile networks. We consider the case of mobility due to impatience during the prefetching and the re-buffering phases when starvation happens. We finally study a system with impatient users controlled by a system manager who has to choose at each decision epoch an action to make in order to optimize the defined system performance. We consider a system in which users come to the system at different time instants and leave it after a finite duration, either after completion of their data transfers or earlier, at the expiry of some patience duration. Numerical analysis and simulations allow us to derive several performance metrics such as mean number of users, the proportion of impatient users who quit the system before completing their file transfers, the throughput, the probability of starvation, the optimal system size in order to optimize the defined performance of the system, etc
Vaton, Sandrine. "Modélisation statistique de trafic sur réseau local : application au contrôle dynamique de bande passante." Paris, ENST, 1998. http://www.theses.fr/1998ENST0025.
Full textFaye, Sébastien. "Contrôle et gestion du trafic routier urbain par un réseau de capteurs sans fil." Thesis, Paris, ENST, 2014. http://www.theses.fr/2014ENST0061/document.
Full textRoad traffic has a significant effect on metropolitan activities, especially during peak hours when it impacts on areas such as the economy and the environment. Road infrastructure is typically coordinated from a control centre that is responsible for maintaining not only its equipment but also their initial settings and incident management (both material and human). During the past few years, new technologies in the fields of information and communication have led to the introduction of intelligent transportation systems. Using multiple measurement points distributed across a country, an operator can count road users and calculate the network load. However, the centralization of information has a number of drawbacks. The aim of this thesis is to study the use of distributed systems in order to implement intelligent transportation systems via a wireless sensor network. Coupled to a detection unit (e.g., a magnetometer), the interconnected sensors can respond to the passage of a vehicle when deployed, for example, along the road. They can also work together without recourse to a central entity - rendering all or part of an urban area totally independent. Furthermore, these networks can operate autonomously and are less susceptible to breadown, because the overall running of the system is not affected by the failure of individual components. Finally, components are small and cheap, and they operate wirelessly, which means they can be deployed and redeployed both rapidly and densely
Faye, Sébastien. "Contrôle et gestion du trafic routier urbain par un réseau de capteurs sans fil." Electronic Thesis or Diss., Paris, ENST, 2014. http://www.theses.fr/2014ENST0061.
Full textRoad traffic has a significant effect on metropolitan activities, especially during peak hours when it impacts on areas such as the economy and the environment. Road infrastructure is typically coordinated from a control centre that is responsible for maintaining not only its equipment but also their initial settings and incident management (both material and human). During the past few years, new technologies in the fields of information and communication have led to the introduction of intelligent transportation systems. Using multiple measurement points distributed across a country, an operator can count road users and calculate the network load. However, the centralization of information has a number of drawbacks. The aim of this thesis is to study the use of distributed systems in order to implement intelligent transportation systems via a wireless sensor network. Coupled to a detection unit (e.g., a magnetometer), the interconnected sensors can respond to the passage of a vehicle when deployed, for example, along the road. They can also work together without recourse to a central entity - rendering all or part of an urban area totally independent. Furthermore, these networks can operate autonomously and are less susceptible to breadown, because the overall running of the system is not affected by the failure of individual components. Finally, components are small and cheap, and they operate wirelessly, which means they can be deployed and redeployed both rapidly and densely
Omnès, Nathalie. "Analyse d'outils de contrôle de la qualité de service dans les réseaux de paquets haut débit." Rennes 1, 2001. http://www.theses.fr/2001REN10134.
Full textFarah, Ihsen. "Optimisation des flux de trafic aérien." Le Havre, 2013. http://www.theses.fr/2013LEHA0003.
Full textIn this thesis, we adress the Air Traffic Flow Management Problem (TFMP). We present a new Integer Linear Program which takes into account all phases of flight. We purpose also a Max-Min ant system algorithm to resolve the TFMP. Numerical simulations are applied to real data to show the effectiveness of our new formulation and our approach. We adress also the static Aircraft Landing Problem (ALP). We propose a quadratic integer program and propose a change of variables to linearize the model. Second objective is to resolve effectivly this model. Therefore, an exact method based on Branch and Bound algorithm is presented. We propose also an Ant Colony System to resolve the instances with a big size. To confirm this work, simulation and computer modeling results for both of the heuristic and exact algorithm are presented
Cathelain, Stéphane. "Contribution à la conception des systèmes coopératifs : application au domaine du contrôle de trafic aérien." Valenciennes, 2005. http://ged.univ-valenciennes.fr/nuxeo/site/esupversions/974efabc-d126-4b2c-a6b4-6fd32b4a7d5c.
Full textCooperative systems design needs the integration of some kinds of tools like the dynamic tasks allocation and support of cooperation and problems resolution activities. The interest of this work is the proposition of a design framework, as a starting point of a formal method, which integrates the different tools in a functional architecture based on the primordial concept of common workspace. The application to the air traffic control field showed the interest of this kind of architecture in the case of an organisation composed of two human operators and an automatic conflict resolution system. The first results shows a modification of human activities with a better anticipation, but it confirms the importance of human-machines interactions and assistances tools design because their utilisation cost must be negligible compared to their benefits
Hoang, Trung Tuyen. "Modélisation et optimisation de la prédictibilité et de la flexibilité du système de gestion de trafic aérien." Thesis, Rouen, INSA, 2009. http://www.theses.fr/2009ISAM0017.
Full textThis thesis aims to model and optimise two components of the air traffic flow management system : predictibility and flexibility. This modelling is equivalent to establishing a relationship between the time window and the rate of arrival flights. Two approachs are used : the analysis of historical data and mathematical modeling. The analysis of historical data was used to establish the relationship between the time window and arrivla rate of flights. It provided the optimal time window but could not show how to modify the system to lead to that time window. Mathematical modeling can not only define the predictability and flexibility in the rigourous manner but also deal with different scenarios of fligths priorities. The combination of DC algorithm with classical methods like Branch and Bound has significantly improved the speed of convergence of solutions and therefore it can be used for the tactical phase of the air traffic flow management
Bouzid, Djamila. "Gestion du trafic temps réel dans le réseau ATM." Toulouse 3, 2002. http://www.theses.fr/2002TOU30037.
Full textSilva, Patricia Maria de Oliveira e. "Contrôle spatio-temporel de la croissance filamenteuse chez Candida albicans." Thesis, Université Côte d'Azur (ComUE), 2018. http://www.theses.fr/2018AZUR4030.
Full textCandida albicans is a fungal human pathogen that can cause life-threatening infections in immunocompromised patients, in part, due to its ability to switch between an oval budding form and a filamentous hyphal form. The small-Rho GTPase Cdc42 is crucial for filamentous growth and, in its active form, localizes as a tight cluster at the tips of growing hyphae. I have used a light-activated membrane recruitment system comprised of the Arabidopsis thaliana Cry2PHR-CibN domains to control the recruitment of constitutively active Cdc42 to the plasma membrane. I have determined how photorecruitment of constitutively active Cdc42 perturbs filamentous growth and where, when and how new filamentous growth is subsequently initiated. My results demonstrate that, upon photorecruitment of constitutively active Cdc42, filament extension is abrogated and a new growth site can be established in the cell. Location of a new filamentous growth site correlates with the length of the initial filament. I have investigated the molecular mechanisms that underlie the disassembly of an initial growth site and the specific location of the new filamentous growth site. In growing hyphae a cluster of vesicles, referred to as a Spitzenkörper, is localized at the tip of the filament. Upon photorecruitment of constitutively active Cdc42, a new cluster of vesicles, with a composition similar to that of the initial Spitzenkörper, appears in the mother cell. I have followed the dynamics of the Spitzenkörper, active Cdc42, sites of endocytosis, secretory vesicles and actin cables subsequent to disruption of the initial growth site in the filament. Taken together, my results suggest that there is competition for growth between the Spitzenkörper and the cluster of vesicles that forms immediately after the photorecruitment of constitutively active Cdc42 and that a dynamic polarity axis can be established in the absence of directional growth
Prot, Damien. "Un nouveau système de trafic aérien à taux de conflits potentiels et consommation énergétique réduits." Grenoble INPG, 2009. http://www.theses.fr/2009INPG0097.
Full textLn this Ph D, we propose the study of a new air traffic system, characterized by a high level of organization. Aircraft are compelled to follow immaterial moving points during their flight. These moving points are organized and sequenced in order to avoid conflicts between aircraft. We consider an underlying problem of this paradigm. It can be seen as a maximum independent set problem on an infinite graph under constraints. We first give theoretical results on this problem and make links with the colouration problem; then we propose resolution heuristics, leading to a global air traffic system. Finally, we develop these heuristics and expose numerical results
Pham, Duc-Thinh. "Prédiction de trajectoire et avis de résolution de conflits de trafic aérien basée sur l’apprentissage automatique." Thesis, Paris Sciences et Lettres (ComUE), 2019. http://www.theses.fr/2019PSLEP027.
Full textThe increasing in traffic demand has strained air traffic control system and controllers which lead to the need of novel and efficient conflict detection and resolution advisory. In the scope of this thesis, we concentrate on studying challenges in conflict detection and resolution by using machine learning approaches. We have attempted to learn and predict controller behaviors from data using Random Forest. We also propose a novel approach for probabilistic conflict detection by using Heteroscedastic Gaussian Process as predictive models and Bayesian Optimization for probabilistic conflict detection algorithm. Finally, we propose an artificial intelligent agent that is capable of resolving conflicts, in the presence of traffic and uncertainty. The conflict resolution task is formulated as a decision-making problem in large and complex action space, which is applicable for employing reinforcement learning algorithm. Our work includes the development of a learning environment, scenario state representation, reward function, and learning algorithm. Machine learning methods have showed their advantages and potential in conflict detection and resolution related challenges. However, more studies would be conducted to improve their performances such as airspace network representation, multi-agent reinforcement learning or controller's strategy reconstruction from data
Guiost, Benoît. "Coopération homme-machine soutenue par un espace de travail commun : application au contrôle de trafic aérien." Valenciennes, 2006. http://ged.univ-valenciennes.fr/nuxeo/site/esupversions/85813850-cb37-4aaa-bda6-8311da6e9476.
Full textThe French services of the Air-Traffic Control system manage the whole of the aircraft which borrow the French airspace at a rate of two million and five hundred thousand flights in 2002. This load of traffic increasing by 3 to 5% per year. The issues of the research presented in this memory is to conceive a co-operative system able to aid the controllers to maintain an optimal security despite traffic increase. The issues of this research affect the definition of the assistance tool, of the functions allocation between operators and tool, and finally of the means making it possible these agents to effectively co-operate. This requires that human operators can control correctly situations to be managed; i. E. That the situation awareness is not reduced by the contribution of new tools. The research aimed in identification of the contents of a Common Workspace to support the co-operative activities of agents, and definition of the new assistant tool' know-how for problems resolution. Work consisted in modeling of the cognitive activities of two air-traffic controllers in co-operation situation. After the implementation on an experimental platform of these new concepts, an evaluation was carried out with professional controllers
Brigui, Amira. "Rôle et contrôle du trafic de Patched dans la voie de signalisation Hedgehog chez Drosophila melanogaster." Paris 7, 2009. http://www.theses.fr/2009PA077030.
Full textThe secreted Hedgehog (HH) proteins act as morphogens in animal development. In vertebrates, HH signalling also controls the fate of stem cells and its deregulation is involved in oncogenesis. The HH receptor Patched (PTC) inhibits the HH pathway in the absence of signal and is itself inhibited by HH binding. PTC also controls the HH gradient by the sequestration and internalisation of HH 4. The transport of PTC is tightly linked to its activity. Here, we analysed the role of two HECT E3 ubiquitin ligases, NEDD4 and SU(DX), in the trafficking and accumulation of PTC in Drosophila. We show that NEDD4 down regulates PTC and is necessary for the endocytosis of free or HH-bound PTC. These effects rely on the interaction of NEDD4 with an L/PPXY (PY) recognition motif conserved in PTC proteins. Internalisation of PTC can be specifically blocked by altering this motif. Thus, PTC endocytosis is essential for its accumulation but not for its intrinsic inhibitory signalling or its ability to bind and retain HH. We also show that SU(DX) is involved in PTC endocytosis and is necessary for lysosomal sorting of PTC in response to HH. Our findings suggest that NEDD4 and SU(DX) cooperate to finely tune the regulation of PTC levels: whereas NEDD4 promutes the constitutive endocytosis and degradation of PTC, SU(DX) appears to be specifically required for the lysosomal sorting and degradation of PTC in cells responding to HH. Finally, given their roles in Notch trafficking, NEDD4 and SU(DX) represent points of potential between these two signalling pathways, which are central to both development and oncogenesis
Bats, Cécile. "Etude du rôle des protéines d'échafaudage dans le contrôle du trafic de surface des récepteurs AMPA." Bordeaux 2, 2006. http://www.theses.fr/2006BOR21348.
Full textThe number of synaptic AMPA receptors is key in controlling glutamatergic transmission. This number results from a dynamic equilibrium between synaptic, exyrtasynaptic and intracellular pools of receptors, and some variations in synaptic strength observed during maturation or plasticity correspond to changes in its set point. Recent data show that receptors exchange between synaptic and extrasynaptic sites by diffusion. Whereas the role of scaffolding proteins in controlling the vesicular trafficking of AMPA receptors is well established, the molecular mechanisms regulating their surface trafficking remain unknown. Here, quantum dots were used to probe the mobility of AMPA receptors at the neuronal membrane. By disrupting the interaction of the receptors with Narp or Stargazin/PSD-95, we have shown that these scaffolding proteins restrict their diffusion. Thus, by controlling the trapping of AMPA receptors at synapses these proteins maintain and potentially modulate synaptic strength
Tabti, Saïd. "Modélisation macroscopique de l'écoulement du trafic aérien : une approche par analyse de données multidimensionnelles." Lyon 1, 1999. http://www.theses.fr/1999LYO10055.
Full textDracinschi, Anca. "Contrôle de congestion dans Internet : un mécanisme unifié pour prévenir la congestion des flots unicast et multicast." Paris 6, 2000. http://www.theses.fr/2000PA066145.
Full textBarnier, Nicolas. "Application de la programmation par contraintes à des problèmes de gestion du trafic aérien." Toulouse, INPT, 2002. http://www.theses.fr/2002INPT022H.
Full textVanderhaegen, Frédéric. "Coopération homme-machine multiniveau entre une équipe d'opérateurs humains et des outils d'assistance : Application au contrôle du trafic aérien." Valenciennes, 1993. https://ged.uphf.fr/nuxeo/site/esupversions/219b0ca2-4e9a-4046-b496-fdc0c9720390.
Full textSanogo, Cheick. "Modeling user impatience and its impact on performance in mobile networks." Electronic Thesis or Diss., Evry, Institut national des télécommunications, 2017. http://www.theses.fr/2017TELE0009.
Full textIn this thesis we study user impatience and quantify its impact on the performance of mobile networks in the presence of elastic user in which we develop two approximate expressions for the stationary distribution of the system: an aggregate one and a detailed one and show their closeness to the exact model. We study mobility of elastic user who may be impatient and quantify its impact on system performance in mobile networks. We consider the case of mobility due to impatience during the prefetching and the re-buffering phases when starvation happens. We finally study a system with impatient users controlled by a system manager who has to choose at each decision epoch an action to make in order to optimize the defined system performance. We consider a system in which users come to the system at different time instants and leave it after a finite duration, either after completion of their data transfers or earlier, at the expiry of some patience duration. Numerical analysis and simulations allow us to derive several performance metrics such as mean number of users, the proportion of impatient users who quit the system before completing their file transfers, the throughput, the probability of starvation, the optimal system size in order to optimize the defined performance of the system, etc
Jouette, Julie. "Phosphoinositides et contrôle de la polarité cellulaire : régulations croisées entre la PIP5K Skittles et les protéines de polarité PAR1 et PAR3." Thesis, Sorbonne Paris Cité, 2017. http://www.theses.fr/2017USPCC118.
Full textCell polarity is a fundamental process that controls cell’s functional and physiological specificities. This process relies on membranous compartments differently composed both on proteins and on phosphatidyl-inositols (PIs). Indeed, through their asymmetric localization, polarity proteins, such as the PAR proteins, are essentials to establish and maintain polarity of the cells. During my PhD, I studied the interplay between the polarity proteins and the PIs. Using the Drosophila egg chamber, as a model, I aimed to characterized the upstream events that regulate the PI(4,5)P2 producing kinase (PIP5K), Skittles (SKTL), activity and localization. I also studied the downstream molecular process that link the PI(4,5)P2, SKTL and the PAR proteins in cell polarity. I contributed to the characterization of the importance of PI(4,5)P2, mainly produced by SKTL in maintaining the apical-basal polarity and during the morphogenesis of the follicle cells. The PI(4,5)P2 is ensuring PAR3 and adherens junctions but not PAR1 proper localizations. Next, through a precise quantification method, I showed that SKTL and the PI(4,5)P2, probably via vesicular traffic, were also ensuring PAR3 proper localizations (anterior accumulation and stage 9B posterior exclusion) in the oocyte. PAR3 accumulation also relies on a Dynein mediated transport and the IKKε kinase while its posterior exclusion relies on PAR1 phosphorylation. Finally, I studied SKTL post translational modifications and their relevance on cell polarity. I identified palmitoylation and phosphorylations that are regulated by the kinase PAR1 and the phosphatase PP1. SKTL phosphorylations seem to be related to its role on the vesicular traffic. Altogether these results clarify some mechanisms involving both PIs and PAR proteins in cell polarity maintaining and establishment
Sanhaji, Ali. "Nouveaux paradigmes de contrôle de congestion dans un réseau d'opérateur." Phd thesis, Toulouse, INPT, 2016. http://oatao.univ-toulouse.fr/17304/1/sanhaji.pdf.
Full textDjiéya, Nganchui Ferry. "Contributions à la conception de systèmes de contrôle de trafic et de gestion de ressources en ATM." Rennes 1, 2002. http://www.theses.fr/2002REN10150.
Full textAnnebicque, David. "Apport de l’aide à la décision à la coopération Homme-Machine : Application au contrôle du trafic aérien." Valenciennes, 2010. http://ged.univ-valenciennes.fr/nuxeo/site/esupversions/9907f088-e1d8-486f-92c9-dc2ea54e6c02.
Full textIn a context of high air traffic, which is constantly increasing, negotiations and exchanges that take place between air traffic controllers will become more and more difficult. The objectives of our work are thus to provide tools for sharing information between air traffic controllers, and proposing them an assistance tool for conflict resolution and a cooperative tool for decision-making taking into account the work habits of these controllers. An approach to identify the decision-making process of human operators (HOs), in order to provide cooperative tools to support decision-making process, is proposed. This approach consists of three steps. The first step is the description of decision-making process of HOs. This step is based on a division into three abstraction levels: strategic, tactical and operational. In a second step, Multi-Criteria Decision-Making Methodology (MCDM) is used to propose a field of investigation in order to construct the potential actions, criteria and preferences that the HOs manipulate. As the MCDM methodology does not suggest any application framework to collect these data, we propose to use a method of repertory grid which will guide the subject, that is to say HOs, in order to obtain maximum information and to determine their criteria and preferences. This is the objective of the third step of the method, which thus consists of a data collection. This method has been implemented with professional controllers from Reims and, by basing on analysis of all these data, new tools have been specified, and guidelines for their validations proposed
Laval, Véronique. "Modélisation de l'activité d'opérateurs d'un système complexe dans une perspective de conception des supports informatisés : le cas du contrôle du trafic aérien." Paris 13, 1993. http://www.theses.fr/1993PA131007.
Full textThe aim of the research is to provide a model of air traffic controllers' activity which could be useful for the design of computer work supports. In particular, this model shoulb be compatible with concepts used for modelling in computer design, so as to help communication between the different people involved in design projects, as well as to promote the integration of ergonomics in these projects. This work is based on a semiological analysis of situated activity, leading to the identification of the essential characteristics of activity, related in particular to its dynamics and its complexity, as well as its stable components through elements of controllers' competence. The following work consists then in attempting to generalize the previous results, in order to go beyond the specificiti es of the situations which have been under observation and analysis, and thus provide a description of activity at an ad equate level, within the scope of design. The result is a generalized model of activity, which concepts can then be adapted to computer design concepts, through restructuring. The foreseeable use of this model, as well as the limits of the work, are finally evaluated, which leads to the identification of research prospects
Ben, Amor Soufian. "Percolation, prétopologie et multialéatoires, contributions à la modélisation des systèmes complexes : exemple du contrôle aérien." Paris, EPHE, 2013. http://www.theses.fr/2008EPHE3001.
Full textA complex system is a system where the global behavior can not be deduced from the behavior of its components. In this thesis, we try to exhibit a common property in most complex systems which is the phenomenon of phase transition. This property allows us to make a link between complex systems and complexity theory. One of the possible reasons of complexity in such systems is randomness. Therefore, in this thesis we are particularly interested in studying complex systems where randomness and diffusion processes are important. At the theoretical level, we proposed a generalization of percolation processes in using pretopology theory. We also developed a mathematical model combining random sets an pretopology theory to study the spatial deformation of sets of elements in random media. At the application level we were interested in studying the congestion of the airspace. By combining a global system approach (Top-Down) and a component based approach (Bottom-Up), we reproduce the same behavior of the congestion dynamics. As a matter of fact, the phase transition is observed when the congestion rate reaches a realistic defined threshold. Finally, we proposed a model combining pretopology theory and random sets to be able to capture simultaneously the generality of the neighborhood concept and the statistical characteristics of a randomly distributed set of elements in the space from a morphological point of view. In the ATM context this is interpreted as the properties of the configuration of the congested areas in the airspace allowing to establish the laws of their underlying mechanisms
LARRIEU, Nicolas. "Contrôle de congestion et gestion du trafic à partir de mesures pour l'optimisation de la QdS dans l'internet." Phd thesis, INSA de Toulouse, 2005. http://tel.archives-ouvertes.fr/tel-00009745.
Full textGaillard, Irène. "Analyse de l'activité et des savoir-faire d'opérateurs experts : le cas des contrôleurs du trafic aérien lors du changement de la position de contrôle." Paris 13, 1992. https://hal.archives-ouvertes.fr/tel-01326227v2.
Full textThis research comes within the framework of an analysis of the activity of experienced air traffic controllers, aimed at identifying their needs for aid during a change in their position. It focuses on the question of analyzing "complex" expertise based on the activity of operators in a work situation. A number of concepts required to analyze the activity with this aim in view, are defined and validated. It is inspired by the theoretical and methodological framework of the "course of action" of theureau and pinsky. The notion of significance for the action is the focal point. Expertise is thus defined as a component of the activity, general elements permitting the activity, in relationship with a representamen and a context. The defined concepts are guidelines for the elaboration of methods of data collection at the real position and with the model of the future control position. The contribution of the study is to define a methodology which will ensure a close relationship between the data collected and the activity being studied. The methods of the "replica position" and the confrontation with the "replica commentary" are proposed as new situations of verbalizations complementary to auto-confrontation