Dissertations / Theses: 'Collective transport system'

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Caetano, Daniel Jorge. "Um sistema informatizado de apoio a usuários de transporte coletivo." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/3/3138/tde-21032006-135820/.

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O principal objetivo deste trabalho foi o desenvolvimento de um sistema informatizado para o auxílio na escolha modal pelos usuários de transporte público. Neste sistema, as alternativas a considerar e soluções geradas devem se basear nas solicitações do usuário e poderão ser usadas para o planejamento tático e/ou estratégico do sistema de transporte considerado. O sistema foi modelado para solução através do algoritmo de fluxo em rede Label Correcting, capaz de lidar com esse problema multimodal, implementado em uma linguagem de programação orientada a objetos. O sistema foi concebido como uma aplicação de internet e, embora seja voltado para um sistema de transporte genérico, foi aplicado e testado com base nas alternativas de transporte disponíveis e malha de ruas da Cidade Universitária Armando de Salles Oliveira.
The main target of this master of science research is the development of a tool to help on modal selection by the public transportation users, which will be implemented as an eletronic information system.Since the infomation must be provided in real time to the user,it is important to the system to be fast and easy to use.It is also a requirement that the system presents options and information to help the user on the selection of the best choice among all possible ones. The alternatives to be considered and generated solutions shall be based on the user requests related to origin and destination of the desired trip. The requests will be stored and could be used for tactic and/or strategic planning of the concerned system of transport. This multimodal problem will be modeled to be solved with the Label Correcting network flow algorithm and implemented using an object oriented language. Although addressed to a generic transport system,it will be implemented and tested based on the available transport alternatives and street mesh of the Cidade Universitaria Armando de Salles Oliveira. The system may be available to users through internet.

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Tomášová, Kateřina. "Zpětný odběr elektrozařízení." Master's thesis, Vysoká škola ekonomická v Praze, 2010. http://www.nusl.cz/ntk/nusl-75299.

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The thesis describes and assess the functioning of the take-back of electrical equipment in Czech Republic. The take-back system is evaluated from a general perspective, it is also used my experience in employment and in society ELEKTROWIN and materials provided to me by the collective system. The theoretical part focuses on the legislative framework of take-back concept, on description of ELEKTROWIN and on financing the system. This part also deals with the main sphere of collective bargaining systems, which are gathering, manipulation, transport and information and educational activities. The application part is focused on the quantity of take-bake of electrical equipment through collective and ELEKTROWIN from the year 2005 to present in a particular years. It also work evaluates observance the requirements from EU directives. The educational activity is evaluated on the basis of a questionnaire as information campaigns to raise public awareness.

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Das, Pragna. "Adaptive multi-robot control through on-line parameter identification at system level." Doctoral thesis, Universitat Autònoma de Barcelona, 2018. http://hdl.handle.net/10803/650337.

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Las instalaciones industriales y de almacenamiento están pobladas por equipos de vehículos guiados automáticos (AGVs por sus siglas en inglés), que se encargan de la logística interna. Las soluciones implementadas, del estado del arte para los procesos de toma de decisiones en la planificación y el control de este tipo de sistemas de robots múltiples (MRSs por sus siglas en inglés) no abarcan el análisis en tiempo real de los comportamientos de los robots y el medio ambiente. Las condiciones de las partes de los robots móviles (MRs por sus siglas en inglés), el estado de carga de las baterías y las condiciones del piso cambian y tienen una gran influencia en los comportamientos. Este trabajo propone un modelo de comportamiento parametrizado que toma en cuenta estos factores y calcula con precisión los costos de transporte a lo largo del tiempo. Al usarlo, el cálculo de los tiempos de recorrido de las rutas proporciona resultados más cercanos a la realidad que con otros métodos basados en longitudes ponderadas, lo que ayuda a tomar mejores decisiones para el control y la administración del sistema. En este trabajo, hemos considerado un modelo de planta que se asemeja al de una fábrica, con varios bloques (unidades de almacenamiento, maquinaria, etcétera) que definen las carreteras y los cruces por los que se mueven los MRs. En este modelo, un grafo, con nodos como puertos (para cargar, descargar, verificar la carga, etcétera), uniones o bifurcaciones, y bordes como las conexiones entre ellos, representa la red de tráfico. Los robots llevan a cabo la tarea de recorrer los bordes para transportar materiales. El tiempo de recorrido de los bordes por MRs se propone como uno de los parámetros de costo. Se ha diseñado un modelo dependiente del estado bilineal para la predicción en tiempo real de los tiempos de recorrido. Los tiempos de viaje se estiman en línea usando este modelo a través de un Filtrado de Kalman. Las trayectorias se calculan constantemente por 100 veces y el promedio de los costos totales de ruta de dichas rutas se compara con el de las rutas obtenidas por los costos heurísticos. Los experimentos muestran que el promedio de los costos totales de rutas para las rutas obtenidas a través de los tiempos de viaje estimados en línea son un 15% menores que los de las rutas obtenidas por los costos heurísticos. Sin embargo, una buena estimación de los tiempos de viaje requiere datos históricos, obtenidos en instancias cercanas. No obstante, hay situaciones en las que los tiempos de viaje, para uno o más bordes durante toda la duración de la operación, no están disponibles para un robot individual. La propensión de esta ocurrencia radica en el hecho de que un borde puede no haber sido recorrido ni siquiera una vez por el robot, o el tiempo de viaje para ese borde se ha registrado en el pasado no reciente. Entonces, es imperativo que ese robot reúna los tiempos de viaje necesarios, de otros robots en el sistema como una observación de referencia. Pero, estas observaciones son de otros robots en diferentes condiciones de batería que el robot en cuestión. Aún así, el modelo puede predecir el tiempo de viaje del robot utilizando la observación de otros robots y su propio cambio o exploración en los tiempos de viaje hasta la instancia actual. El quid de este proceso es predecir los tiempos de viaje actuales en el robot utilizando el tiempo de viaje de otros para el mismo borde. El mecanismo de intercambio de información entre un robot y otros en el sistema se ha diseñado en forma de un conocimiento común basado en la ontología. Esta estructura de ontología es idéntica en cada robot y contiene los tiempos de viaje de los bordes con contextos adjuntos a cada dato sobre las posturas, los nodos que ese borde particular conecta y otras informaciones. Esta ontología ayuda a buscar y compartir información formando una base de conocimiento colectiva. Esto ayuda mucho al MR a estimar los tiempos de recorrido con mayor precisión. Esto afecta la planificación de rutas para encontrar rutas con un menor costo de ruta total. El promedio del costo total de 100 rutas generadas a través de los tiempos de recorrido obtenidos con el uso de información compartida es un 40% menor que el de las rutas generadas a través de los tiempos de recorrido sin compartir información.
Teams of automatic guided vehicles (AGVs) populate industrial and warehousing facilities and take care of the internal logistics. State-of-the-art, implemented solutions for decision-taking processes in planning and control of such kind of multi-robot systems (MRSs) do not encompass real-time analysis of behaviors of robots and environment. Conditions of parts of the mobile robots (MRs), state of charge of batteries and floor conditions change and have strong influence on behaviors. This work proposes a parameterized behavioral model which takes these factors into account and accurately estimates transportation costs over time. By using it, computation of path travel times gives results closer to reality than by other methods based on weighted lengths, thus helping to take better decisions for system control and management. In this work, we have considered a plant model that resembles that of a factory, with several blocks (storage units, machinery and so on) that define the roads and crossings where MRs move. In this model, a graph, with nodes being ports (for loading, unloading, load checking, et cetera) or junctions and bifurcation and edges being the connections among them, represents the traffic network. The robots carry out the task of traversing edges to carry materials. The travel time of edges by MRs is proposed as one such cost parameter. A bi-linear state dependent model has been devised for real-time prediction of travel times. The travel times are estimated online using this model through Kalman Filtering. The paths are computed constantly for 100 times and average of total path costs of these paths are compared with that of paths obtained by heuristics costs. The experiments show that average total path costs of paths obtained through on-line estimated travel times are 15% less that of paths obtained by heuristics costs. Nevertheless, a good estimation of travel times requires historical data, obtained at close instances, but there are situations when travel times for one or more edges for the entire duration of operation are not available to an individual robot. The proclivity of this occurrence lies in the fact that edge may not have been traveled even once by the robot, or travel time for that edge have been recorded not in recent past. Then, it is imperative for that robot to gather the necessary travel times from others in the system as a reference observation, but these observations are from other robots in diﬀerent battery condition than itself. Still, the model can predict travel time for the robot using other robots’ observation and its own change or exploration in the travel times until the current instance. The crux of this process is to predict current travel times in the robot using others’ travel time for the same edge. The mechanism of information sharing between one robot to others in the system has been devised in a form of a common ontology-based knowledge. This ontology structure is identical in each robot which contains the travel times of edges with contexts attached to each data about the stances, the nodes of the edge connects and other information. This ontology helps to fetch and share information forming a collective knowledge base. This greatly helps the MR to estimate travel times more accurately. This aﬀects route planning to find paths with lesser total path cost. The average of total cost of 100 paths generated through travel times obtained with sharing is 40% less than that of paths generated through travel times without sharing.

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Poublan-Attas, Valérie. "L'espace urbain déformé : Transports collectifs et cartes mentales." Phd thesis, Marne-la-vallée, ENPC, 1998. http://www.theses.fr/1998ENPC9809.

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L’intérêt pour les transports collectifs ne cesse de croître avec la prise de conscience des problèmes engendrés par le « tout automobile ». Dans ce contexte, les transports en commun en site propre, et particulièrement les tramways, reconquièrent les villes. Toutes ces nouvelles orientations représentent des sommes d’argent considérables, c’est pourquoi les questions de conception et d’évaluation des projets de transport public sont cruciaux. Cette thèse développe une méthode qualitative d'aide à la conception et à l'évaluation des réseaux de transports collectifs et s'intéresse, plus spécifiquement aux lignes de tramway. La méthode constitue aussi un outil puissant de pondération des outils quantitatifs. Toute personne possède une représentation mentale de l'espace urbain qu'elle parcourt réellement ou virtuellement. Les réseaux de transport collectif influencent les cartes mentales de l'espace urbain. Ils contraignent la perception que les gens ont de la ville à travers leurs itinéraires mais aussi modifient les distances entre les points, créant un espace-temps spécifique. Cependant, les cartes mentales, tels des instruments de navigation, agissent par activations sélectives ou abandon de certaines branches du réseau. C'est pourquoi l'étude des représentations mentales, de leur capacité à intégrer des éléments nouveaux comme une nouvelle ligne de transport public est capitale. Cette recherche étudie les éléments constitutifs des cartes mentales puis la manière dont celles-ci évoluent avec la mise en service d’une nouvelle ligne de transport collectif. Elle s’intéresse aussi à la taille, à la localisation des territoires d’appartenance des individus et à leurs évolutions, question essentielle pour désenclaver les quartiers en difficulté. Les enseignements cernent les éléments du transport collectif qui déterminent fortement les représentations mentales. La topologie de celles-ci, les seuils de perception sont analysés en particulier et partiellement expliqués. Enfin, les cartes mentales peuvent se regrouper par types selon leur capacité à intégrer des éléments nouveaux. Chaque type correspond à un profil d'individu. Cette conclusion est capitale car elle permet, par l'utilisation de la méthode, d'évaluer dans quelle mesure les représentations mentales des individus, concernés par un projet de transport collectif, sont enclines à intégrer la future ligne ou non. Les résultats de cette recherche, ainsi que la méthode développée, sont autant d'enseignements précieux pour un aménageur ou, de manière générale, un décideur en matière d'urbanisme et de transport
Passengers, both actual and potential, have a certain idea about the accessibility (in the geographical sense of the word meaning « possibility of access ») offered by an urban public transport network. The dependent factors are linked to the individual (status, usual method of transport, his urban experience, …) ; to the characteristics of the journey, real or virtual : his own perception of the transport offer as well as his perception of the area covered by the network. Planning generally takes the first two elements into account. The generalized costs of travel are calculated (journey time and value of time) or activity programmes are determined. The aim of this study is to examine those elements not normally taken into account but which affect what we label topological representation. Due to the « anisotropy » which a public transport network creates between different directions or more specifically the different routes within the space, it modifies the distance between points, thus creating a special time-space. It transforms the relative positions of places, or in other words the topology. In this way, the transport network plays on the feelings of nearness, distance and the idea of connection. It transforms both the limits of the territory an individual belongs to and th neighbouring areas. It can thus be seen mental maps as a form of analysis, that the network influences our representation of space. Mental maps play a supporting role to an individual’s transport strategy. Due to the effect of feedback, the maps have a direct or indirect influence on the structuration of even spatial networks by selective activation or decline of certain areas. The knowledge of the relationship between territorial structures and cognitive schematic description of actions using mental maps, can contribute towards enriching methods used in the planning and evaluating of transport networks

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Bottinelli, Arianna. "Modelling collective movement and transport network formation in living systems." Doctoral thesis, Uppsala universitet, Tillämpad matematik och statistik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-303943.

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The emergence of collective patterns from repeated local interactions between individuals is a common feature to most living systems, spanning a variety of scales from cells to animals and humans. Subjects of this thesis are two aspects of emergent complexity in living systems: collective movement and transport network formation. For collective movement, this thesis studies the role of movement-mediated information transfer in fish decision-making. The second project on collective movement takes inspiration from granular media and soft mode analysis and develops a new approach to describe the emergence of collective phenomena from physical interactions in extremely dense crowds. As regards transport networks, this thesis proposes a model of network growth to extract simple, biologically plausible rules that reproduce topological properties of empirical ant trail networks. In the second project on transport networks, this thesis starts from the simple rule of “connecting each new node to the closest one”, that describes ants building behavior, to study how balancing local building costs and global maintenance costs influences the growth and topological properties of transport networks. These projects are addressed through a modeling approach and with the aim of identifying minimal sets of basic mechanisms that are most likely responsible of large-scale complex patterns. Mathematical models are always based on empirical observations and are, when possible, compared to experimental data.

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Bromley, II Michael William. "Pneumatic Particulate Collection System Analysis and Design." Thesis, Virginia Tech, 2012. http://hdl.handle.net/10919/33562.

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A pneumatic particulate collection system harnesses the energy associated with the release of a compressed gas to transport particulate to a collection chamber. In an effort to improve the efficiency of a previously designed collection system, high speed imaging in conjunction with computational fluid dynamics (CFD) was utilized to highlight design deficiencies. Areas of recirculation within the collection device as well as impingement of the sampling surface were observed through the testing and CFD analysis. The basis of the improved collection system was conceived through research of pneumatic transport and the deficiencies found through testing and simulation. An improved rectangular-duct-styled system was designed in three main stages. A variety of filters used to contain the desired particulate were characterized through testing for use in simulations as well as fluids calculations. The improved system was then analyzed utilizing compressible and incompressible flow calculations and design iterations were conducted with CFD to determine the final parameters. The final design was simulated with a multiphase flow model to examine the particulate entrainment performance. The improved collection system efficiently expanded and developed the gas flow prior to the collection area to employ the particulate entrainment process. The final design was constructed with an additive manufacturing process and experimentally tested to validate the simulations and flow calculations. The testing proved that the final design operated purely on particulate entrainment and collected only the top layer of particles as simulated. The improved collection system eliminated all areas of flow recirculation and impingement of the particle bed to provide a more efficient sampling device.
Master of Science

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Sun, Ting. "La place du transport semi-collectif dans les mutations des systèmes de mobilité urbaine en Chine : Le cas de Shanghai." Thesis, Paris Est, 2016. http://www.theses.fr/2016PESC1189/document.

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Dans le contexte du développement rapide des villes chinoises, l’expansion de la ville et les nouvelles zones de développement entraînent de forte besoins de mobilité. Le transport public ne peut satisfaire toutes les demandes des déplacements des citadins. Ils organisent leurs propres services, les transports semi-collectifs, par une approche de bas en haut. Avec les avantages de l’adaptation locale, du service à la demande et de la flexibilité, ce type de transport devient un mode important pour leurs vies moderne. Pourtant, ce transport est en dehors du système du transport traditionnel. Le cadre juridique et institutionnel actuel n’est pas adapté à l’exploitation de ces transports spontanés. La réglementation gouvernementale sur ce type de transport montre aussi une difficulté en raison du manque d’un cadre convenable. De plus, le système du transport urbain durable demande une intégration des divers modes des transports. La relation entre le transport semi-collectif et les autres moyens du transport devient une question essentielle. De ce fait, nous proposons des approches de l’évolution du cadre juridique et institutionnel, de l’amélioration de l’organisation et l’exploitation ainsi que de l’intégration dans le système du transport urbain, afin de créer un environnement innovant pour l’avenir du transport semi-collectif
In the context of the rapid development of Chinese cities, the expansion of the city and the new areas of developments lead the strong mobility needs. Public transport cannot meet all the demands of movement of citizens. They organize their own services, paratransit, with an approach bottom-up. With the advantages of local adaptation, on-demand service and flexibility, this transport becomes important to their modern lives. However, this transport is out of the traditional transport system. The current legal and institutional framework is not suitable for the operation of this spontaneous transport. Government regulations on this type of transport also show difficult because of lack of suitable frames. In addition, the sustainable urban transport system requires integration of various modes of transport. The relationship between the paratransit and other transportation modes is another key issue. Therefore, we propose approaches to change legal and institutional framework, to improve organization and operation and integrate this mode in the system of urban transport, to create an innovative environment for future of paratransit

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Prendiville, Alison. "An investigation into the design and specification of revenue collection systems in urban mass transit." Thesis, University of East London, 2001. http://roar.uel.ac.uk/1226/.

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This thesis describes the nature of the specification and design of revenue collection systems from four urban mass transit systems: Manchester Metrolink, Sheffield Suptertram, Grenoble Tag Light Rail system and the Netherlands National Ticketing system. Previous research in this area has been generated from an industry perspective that has focused on new technologies and types of ticketing systems available. In addition fare collection is frequently discussed, and there is academic research available, in relation to pricing theory and policy. However, as yet there appears to be no theoretical or empirical research examining urban mass transit revenue collection systems and their specification. This research was initiated from a supplier of revenue collection systems expressing dissatisfaction in the design and specification selection procedure. In addition there was a need to conceptualise the important role that a revenue collection system plays in achieving a public transport operator's objectives. The aim of this study was to add to the theoretical base of this research area through the four case studies and to improve the design and selection of revenue collection systems in `real life' situations. Due to the nature of the research area being `real world' and revenue collection systems being bespoke, theoretical propositions were created from the literature review in order to guide the research and test the hypothesis. Through the theoretical proposition the role of the revenue collection system in a service marketing context is also established. This thesis is presented in seven chapters. Chapter 1 provides an introduction and background information to the research area. In Chapter 2 the research methodology is discussed together with the nature of the research. In Chapter 3 the literature review and the generation of the theoretical propositions and hypothesis are presented. In Chapter 4 the case studies describe the nature of the revenue collection systems and their specifications. In chapter 5 the case study analysis is undertaken based upon the theoretical propositions. Chapter 6 presents the overall conclusions and tests the hypothesis; it also presents recommendations for improving revenue collection system specification. Finally Chapter 7 discusses the research and its strengths and weaknesses and suggests areas for further research.

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Führ, Gustavo. "Pedestrian tracking and collective behavior recognition." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/157971.

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A análise de comportamento coletivo e rastreamento de pedestres apresentam diversas aplicações, especialmente em sistemas de vigilância inteligente. Neste trabalho é proposta uma solução compreensiva com objetivo de atingir rastreamento de pedestre e reconhecimento de atividade coletiva de maneira robusta baseada na utilização de câmeras calibradas. Primeiramente, com o objetivo de remover a necessidade de calibração manual, nós apresentamos um método de calibração automática que explora detectores de pedestres e remoção de fundo para calibragem baseada em otimização não-linear. Adicionalmente, nós propomos a utilização da matriz de calibração para gerar candidatos coerentes com a geometria de cena em detectores de pedestres. Nossa abordagem tem como objetivo diminuir o intervalo de escalas comumente utilizado em detectores baseados em janelas deslizantes, gerando um número menor de extrações de atributos e reduzindo o número de falsos positivos na detecção. Em seguida, nós propomos um método de rastreamento de múltiplos pedestres utilizando câmeras calibradas. Nossa abordagem explora histogramas de cor para rastrear os pequenas regiões (patches) de cada alvo. Os vetores de deslocamento obtidos através do pareamento de atributos de aparência são combinados com um vetor obtido através de um preditor de movimento em coordenadas de mundo. Adicionalmente, nós incluímos informações originárias de detectores de pedestres para aumentar a acurácia do sistema e sua habilidade de recuperação a falhas. Por fim, nós propomos uma abordagem hierárquica de duas camadas para o problema de reconhecimento de atividade coletiva baseada no uso de classificadores Random Forests. No primeiro nível da técnica proposta, nós utilizamos distâncias entre pares de pessoas e suas respectivas velocidades relativas para classificar interações de pares. Estas interações são combinadas com a dinâmica do formato do grupo observado (e sua respectiva velocidade) para o reconhecimento de atividades coletivas. Os experimentos realizados neste trabalho demonstram a qualidade de nossas abordagens em sequências de vídeos disponíveis publicamente. Nossos resultados mostram serem competitivos quando comparados com técnicas do estado da arte e, particularmente, apresentam uma boa generalização entre diferentes cenários de captura de vídeo.
Collective behavior detection and pedestrian tracking present many applications, specially in surveillance systems. In this dissertation, we proposed a complete pipeline for achieving robust tracking and collective behavior recognition based on calibrated static cameras. To remove the necessity of manual calibration, we first present a fully automatic self-calibration system that explores pedestrian detection results and background removal at non-consecutive frames in order to calibrate a static camera using a non-linear cost function. We also propose the use of camera calibration to generate geometrically coherent candidates for pedestrian detection. Our approach aims to reduce the scale range typically used in sliding-window techniques, which leads to less feature extractions and decreased number of false positives. Then, we propose a multi-target pedestrian tracking algorithm using a calibrated static camera. The tracking approach explores color histograms to track patches of each target. Obtained displacement vectors are combined with the expected motion of pedestrians in the world coordinate system. The proposed tracker also incorporates pedestrian detector results to improve the system’s accuracy and its ability to recover from failure. Finally, we propose a two-layered approach for collective behavior recognition based on Random Forests classifiers. In the first level, we use inter-personal distances and relative speeds computed in the world coordinate system to classify asymmetrical pair interactions. Those interactions are combined with group shape dynamics and mean velocity to recognize the collective behavior. We devise a set of experiments to attest the quality of our approaches using publicly available datasets. Results have shown to be competitive against state-of-the-art techniques, and particularly of good generalization across different databases.

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Finch, Craig. "Modeling transport and protein adsorption in microfluidic systems." Doctoral diss., University of Central Florida, 2011. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4762.

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This work describes theoretical advances in the modeling and simulation of microfluidic systems and demonstrates the practical application of those techniques. A new multi-scale model of the adsorption of hard spheres was formulated to bridge the gap between simulations of discrete particles and continuum fluid dynamics. A whispering gallery mode (WGM) biosensor was constructed and used to measure the kinetics of adsorption for two types of proteins on four different surfaces. Computational fluid dynamics was used to analyze the transport of proteins in the flow cell of the biosensor. Kinetic models of protein adsorption that take transport limitations into account were fitted to the experimental data and used to draw conclusions about the mechanisms of adsorption. Transport simulations were then applied to the practical problem of optimizing the design of a microfluidic bioreactor to enable “plugs” of fluid to flow from one chamber to the next with minimal dispersion. Experiments were used to validate the transport simulations. The combination of quantitative modeling and simulation and experiments led to results that could not have been achieved using either approach by itself. Simulation tools that accurately predict transport and protein adsorption will enable the rational design of microfluidic devices for biomedical applications.
ID: 031001510; System requirements: World Wide Web browser and PDF reader.; Mode of access: World Wide Web.; Co- Title from PDF title page (viewed August 5, 2013).; Thesis (Ph.D.)--University of Central Florida, 2011.; Includes bibliographical references (p. 117-133).
Ph.D.
Doctorate
Psychology
Sciences
Modeling and Simulation

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GONZALEZ, GUSTAVO ANDRES ARAQUE. "PLANNING OF SPECIAL SOLID HOUSEHOLD WASTE COLLECTION THROUGH THE USE OF TRANSPORT GEOGRAPHIC INFORMATION SYSTEM." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2015. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=25336@1.

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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO
COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
PROGRAMA DE SUPORTE À PÓS-GRADUAÇÃO DE INSTS. DE ENSINO
O crescimento da população no mundo inteiro tem gerado nos últimos anos o nascimento de novas economias e o aumento nos níveis de demanda dos produtos. Com os novos perfis dos consumidores e as novas tendências das mercadorias, as empresas estão criando produtos com ciclo de vida curto, aumentando a geração de Resíduos Sólidos Domiciliares nos municípios. Devido ao fenômeno anterior, o número de pontos de coleta nos itinerários dos veículos aumenta, gerando custos e distâncias maiores, diminuindo a produtividade e qualidade do Sistema de Transporte das empresas de limpeza. Nesta dissertação apresenta-se o planejamento das rotas de coleta de Resíduos Sólidos Domiciliares do Programa de Remoção Gratuita da Companhia Municipal de Limpeza Urbana – COMLURB na zona sul da cidade do Rio de Janeiro, como método de apoio na logística de transporte do sistema de limpeza da cidade. Para tal objetivo, utilizou-se o Sistema de Informação Geográfica para Transporte (SIG-T) TransCAD versão 5.0 Academic Licence com a aplicação do Problema de Roteirização dos Veículos com Janela de Tempo (PRVJT). Os resultados obtidos nas análises reduziram a distância total executada pelos veículos em 30,34 por cento, demostrando a importância da metodologia em problemas de transporte reais.
Population growth worldwide has generated in recent years the emergence of new economies and the increased levels of demand for products. With the new profiles of consumers and new trends of goods, companies are creating products with short life cycle, increasing the generation of Household Solid Waste in the municipalities. Due to the previous phenomenon, the number of collection points on the routes of vehicles increases, generating costs and greater distances, decreasing the productivity and quality of the transport system of cleaning companies. In this dissertation presents the planning of the waste collection routes of Household Solid Free Removal Program of the Municipal Company of Urban Cleaning - COMLURB in the south of the city of Rio de Janeiro, as a support method in the Transport Logistics of city cleaning system . For this purpose, we used the Geographic Information System for Transportation (GIS-T) TransCAD version 5.0 Academic License to the implementation of the Vehicle Routing Problem with Time Windows (VRPTW). The results obtained in this study reduced the overall distance traveled by vehicles in 30, 34 per cent, showing the importance of the methodology in real transportation problems.

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Tounkara, Abdoulaye. "Le systeme des transports collectifs urbains de bamako : organisation, fonctionnement et modalites de financement." Lyon 2, 1989. http://www.theses.fr/1989LYO22011.

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La ville de bamako connait une forte croissance demographique (environ 7%, deux fois superieur a la moyenne nationale) et un developpement spatial, avec la naissance de quartiers a la peripherie. Cette evolution ne va pas sans poser des problemes de deplacements des populations. Le contexte de developpement urbain joue sur les transports, et inversement, le transport peut favoriser le developpement urbain, non seulement par l'efficacite induite grace a sa bonne marche et son effet sur les autres secteurs de l'economie urbaine, mais aussi, parce que l'activite de transport s'integre, dans le schema d'accumulation generale. Le lien etroit qui existe entre la ville et son systeme de transport nous amene au rejet des categories inadaptees (formel, informel), meme su le transport collectif urbain est assure par une multitude de transporteurs dont les 90% ne possedent qu'un vehicule, au profit d'une approche integree (systeme urbain, systeme de transport), et d'une approche dynamique, sous l'eclairage du financement. L'ampleur de la crise economique lance l'interet de la privatisation des transports collectifs. Une meilleure connaissance des modalites de financement permet d'apprecier la place des transports urbains dans le phenomene d'accumulation. Identifier les modalites de financement, c'est a terme, apprecier la capacite de financement des acteurs du systeme urbain. La stabilite du systeme depend des termes du partage du surplus de l'activite de transport
The city of bamako has a strong demographic growth : the demographic development rate of about 7% is twice as important as the national average. The creation of districts in the outskirts contributes to the spatial development of this growth. This evolution causes moving problems for the populations. The urban development context influences transports and, on the other hand, trans, port can favor urban development. It may do so not only by effectiveness realised thanks to its good functioning and its effect on other sectors of urban economics, but also because the transport activity integrates into the schedule of general accumulation. The tight link existing between the city and its transport system makes use refuse the inadapted categories (formal, informal), even if the public transport is assured by a great number of transporters of which 90% only posess one vehicle. We favor an integrated (urban system, transport system) and a dynamic approach, in the light of financing. The scale of the economic crisis puts to the fore interest of putting the public transport into private hands. Thanks to a better knowledge of the financing modalities we can appreciate the place of the urban transport in the accumulation phenomenon. Identifing the financing modalities means, on the long run, apprecianting the financing capacities of the urban system actors. The stability of the system depends on the sharing terms of the transport activity

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Ocana, Ortiz Rosa. "LA REORGANISATION DU SYSTEME DE TRANSPORT COLLECTIF DE SURFACE A CARACAS A PARTIR DE LA MISE EN SERVICE DU METRO." Phd thesis, Université Paris XII Val de Marne, 1993. http://tel.archives-ouvertes.fr/tel-00345085.

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A Caracas, comme dans la plupart des villes où il a été envisagé de mettre en place un métro, celui-çi est conçu comme l'épine dorsale du système de transport de la ville. Pour mettre cette conception en pratique, il est normalemeont nécessaire de restructurer le réseau de transport de surface et de repenser le système de transport. Le modèle promu par la RATP, concepteur du métro de Caracas, implique en particulier de s'attacher aux relations entre les différents modes de transport, à travers la création d'une autorité organisatrice de transport et une intégration intermodale (physique, tarifaire et institutionnelle). A Caracas, comme ailleurs, ces problèmes sont abordés dans le projet du métro mais sur le terrain, peu de solutions concrètes sont évoquées. D'où l'objet de cette thèse de connaître la transformation de l'offre de transport collectif urbain de Caracas après la mise en service du métro et de comprendre pourquoi l'intégration des différents modes de transport collectif urbain a été impossible

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14

Soui, Makram. "Contribution à l’évaluation des systèmes d’Information personnalisés : Application au transport collectif de personnes." Valenciennes, 2010. http://ged.univ-valenciennes.fr/nuxeo/site/esupversions/7d269547-a749-46f6-80fa-49bb22ffe41b.

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Les systèmes d’information personnalisés (SIP) sont de plus en plus présents dans la vie de tous les jours, aussi bien chez soi que dans le cadre du travail. Ils possèdent de plus en plus différentes capacités d’adaptation, ils sont disséminés dans l’environnement de l’utilisateur. De nombreux travaux sont menés aussi bien dans le monde académique que dans celui des entreprises sur la modélisation de l’utilisateur, les méthodes de conception, les outils de construction d’interfaces adaptées, les algorithmes de personnalisation, etc. Cependant, l'évaluation de ces systèmes est souvent négligée, voire ignorée. Pour combler ce manque, il s’agit d’étudier et mettre en place une batterie de méthodes permettant d’évaluer et d’améliorer leur qualité de personnalisation. Des verrous scientifiques liés à l’évaluation des SIP apparaissent. C’est dans ce contexte que nous proposons trois démarches complémentaires d’évaluation. La première est intitulée MetQus (METhode d’évaluation basée sur le QUeStionnaire de satisfaction). La seconde prend la forme d’une évaluation précoce qui consiste à prévoir l’évaluation dès les premières étapes de développement en intégrant un système de trace ; elle est intitulée MetTra (METhode d’évaluation qualifiée de précoce basée sur les TRAces d’usage). La troisième correspond à une évaluation par simulation d’une maquette de SIP, intitulée MetSim (METhode d’évaluation par SIMulation). MetSim permet de détecter les problèmes engendrés suite au changement du contexte en se basant sur un système à base de cas. Le cadre applicatif concerne l’évaluation des systèmes d'information personnalisés dans le domaine des transports collectifs des personnes
The personalized information systems (PIS) are more and more present everywhere (at home, at work, in public places, etc. ). More they can have different adaptation capabilities, and can be disseminated in the user environment. Many studies in research and in industry are conducted about user modelling, design methods and tools for HCI generation. However, the evaluation of such systems is often neglected. To fill up this lack, it is necessary to envisage new evaluation methods focused personalization quality. Difficulties concerning context-centred evaluation appear. In this research field, we propose three complementary approaches dedicated to personalized interactive system evaluation. The first one is called MetQus; it consists in collecting behavioural information concerning the system use, using a questionnaire. The second one is called MetTra; it consists in foreseeing the evaluation from the early stages of application development by integrating a tracing system. The last one is called MetSim; it allows an evaluation by simulation of PIS mock-up. MetSim is based on Case Based Reasoning system to identify problems. These evaluation approaches have been validated by applying them to evaluate PIS in transport field

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Gustafsson, Linder Rebecca, and Paulina Lindqvist. "Effects on traffic work during demand-based collection of waste compared with collection at fixed intervals." Thesis, Linköpings universitet, Kommunikations- och transportsystem, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-177543.

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Avfallshämtningen är ett komplext problem som ställer mängder av logistiska krav och bör tillgodose kundens behov om att få sina sopor upphämtade och tömda i rätt tid. Samtidigt bör onödigt trafikarbete minskas för att uppnå en mer hållbar avfallshämtning. Nodra AB sköter avfallshämtningen av det kommunala avfallet i Norrköpings kommun. I dagsläget finns olika abonnemang för Nodra ABs kunder att välja på där avfallet hämtas enligt schemalagda rutter med fasta intervall. Nodra AB vet dock att behovet hos kunderna kan skilja sig från det standardiserade behovet, vilket riskerar att leda till att halvtomma eller överfulla kärl töms. För att se om denna risk går att minimera driver Nodra AB nu ett projekt, Behovsbaserad insamling, där syftet är att utreda om Norrköpings kommun ska gå mot en mer behovsbaserad avfallshämtning. Detta examensarbete avsåg att analysera effekterna på trafikarbetet av att gå från traditionell avfallshämtning med fasta intervall till en behovsbaserad avfallshämtning. Tidsåtgången och koldioxidutsläppen för trafikarbetet ämnades också att analyseras. Målet med examensarbetet var att det skulle fungera som ett komplement till Nodra ABs projektarbete och deras beslutsunderlag inför ett eventuellt införande av behovsbaserad avfallshämtning från fritidshus. Examensarbetet har innefattat både kvalitativa och kvantitativa metoder. En litteraturstudie har genomförts i syfte att få mer kunskap gällande transportplanering och logistiken kring avfallshämtning samt de miljömässiga effekterna transporter ger upphov till idag. Information kring hur Nodra AB arbetar i nuläget har samlats in i form av en intervju med berörd projektledare samt utredningsingenjör och även en observation för att skapa en bättre förståelse. Analysen i examensarbetet grundades på två olika scenarier för en behovsbaserad avfallshämtning. Båda utgick ifrån att ordinarie rutter och intervall bibehölls, men att i det första scenariot endast tömma de kärl som ställts fram vid hämtstället och i det andra scenariot endast tömma de kärl där kunden beställt hämtning via en app. Analysen utgick från att behovet bland fritidshus minskade med 25% under veckorna 2433 och 50% under veckorna 1923 samt 34 38. Inför analysen har data från Nodra AB tillhandahållits, i syfte att kunna beräkna en förändring i körlistorna. För att få fram förändringen i körtid och körsträcka har programvaran ArcMap använts. Resultatet har sedan sammanställts med övriga data i en beräkningsmodell i Microsoft Excel. Resultatet visade på att en behovsbaserad avfallshämtning med minskat behov ger en minskad körsträcka, som leder till tidsbesparingar samt ett minskat koldioxidutsläpp. Resultatet visar dock inte vilka effekter ett ökat behov ger och de finns även övriga aspekter som inte tagits med i detta arbete, som kan påverka trafikarbetet.

Examensarbetet är utfört vid Institutionen för teknik och naturvetenskap (ITN) vid Tekniska fakulteten, Linköpings universitet

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Muth, Aaron. "Design, Synthesis, and Biological Evaluation of Novel Polyamine Transport System Probes and their Application to Human Cancers." Doctoral diss., University of Central Florida, 2012. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5348.

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The mammalian polyamine transport system (PTS) has been of interest due to its roles in cancer and maintaining cellular homeostasis. Polyamines are essential growth factors which are tightly controlled via a balance of biosynthesis, metabolism, import, and export. This work focused on the development and biological testing of polyamine transport probes to help understand the molecular requirements of the PTS. This was mediated through the use of a CHO (PTS active) and CHO-MG* (PTS deficient) screen, where compounds demonstrating high toxicity in CHO and low toxicity in CHO-MG* were considered PTS selective. The first chapter focused on the development of polyamine-based drugs which are both metabolically stable to polyamine oxidase (PAO) activity and are hyperselective for targeting the PTS. This approach was optimized by combining a di-substituted aryl design with terminal N-methylation of the appended polyamine chains to generate a new class of superior PTS agonists. The metabolic stability of these compounds was demonstrated in CHO and CHO-MG* in the presence and absence of a known PAO inhibitor, aminoguanidine (AG). Highly PTS selective compounds were then tested in the NCI-60 cell line screen to demonstrate the effectiveness of polyamine-based drugs in cancer therapy. During this screen, the MALME-3M (human melanoma) cell line was identified as being very sensitive to these PTS targeting drugs. Further studies using MALME-3M and its normal counterpart, MALME-3, showed excellent targeting of the cancer line over MALME-3. For example, The MeN44Nap44NMe compound showed 59-fold higher toxicity in MALME-3M over MALME-3. The second chapter focused on the development of potential polyamine transport inhibitors (PTIs) for use in combination therapy with ?-difluoromethylornithine (DFMO). This therapy is predicated upon reducing sustained polyamine depletion within cells by inhibiting both polyamine biosynthesis with DFMO and polyamine transport with the PTI ligand. Potential PTIs were identified by blocking the uptake of spermidine in DFMO-treated CHO and L3.6pl cells. Previous work has identified a tri-substituted polyamine-based design as an effective PTI. Low toxicity and a low Ki value in a L1210 screen were good predictors for PTI efficacy. The structural requirements for a potent PTI were explored by modulating the toxicity through the introduction of amide bonds, and also by determining the number and orientation of the polyamine messages (appended to an aryl core) required for efficient inhibition of polyamine uptake. These experiments showed that a tri-substituted design and a triamine message (homospermidine) appended was optimal for PTI potency. The final chapter focused on the development of Dihydromotuporamine C derivatives as non-toxic anti-metastatic agents. Dihydromotuporamine C demonstrated good anti-invasive properties with tumor cells. Derivatives were made in an effort to reduce the cytotoxicity of the parent and improve the anti-migration potency. The motuporamine derivatives all have a polyamine message (norspermidine or homospermidine) appended to make a macrocycle core, making them prime targets to evaluate as potential PTS ligands in the CHO and CHO-MG* screen. Each compound was also tested in the highly metastatic pancreatic cancer cell line L3.6pl to determine both its IC50 value and maximum tolerated dose (MTD). The anti-migration assay was performed at the lowest MTD obtained (0.6 [micro]M) in order to compare the series at the same non-toxic dose. The results suggested that as the N1-amine center was moved further from the macrocyclic ring, an increased ability to inhibit cell migration and reduced toxicity was observed. These collective findings provide new tools for cell biologists to modulate and target polyamine transport in mammalian cells. Future applications of these technologies include new cancer therapies which are cell-selective and inhibit the spread of tumors.
Ph.D.
Doctorate
Chemistry
Sciences
Chemistry

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17

Pelton, Sabine S. "Spin Pumping in Lateral Double Quantum Dot Systems." Master's thesis, University of Central Florida, 2012. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5369.

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Electron transport in single lateral quantum dot (QD) and parallel lateral double quantum dot (DQD) systems is modeled using semiclassical rate equations. The Zeeman effect, in conjunction with resonant tunneling, is used to select the spin of electrons involved in transport. We show adiabatic spin pumping by periodic variation of the systems' confining parameters, namely the quantum point contacts (QPCs) dictating the boundaries of the dots, and the gate voltage applied to each dot. The limitations of adiabatic spin pumping are subsequently examined by counting the average spin pumped per cycle when frequency and interdot capacitance are adjusted.
ID: 031001288; System requirements: World Wide Web browser and PDF reader.; Mode of access: World Wide Web.; Adviser: Eduardo Mucciolo.; Title from PDF title page (viewed February 26, 2013).; Thesis (M.S.)--University of Central Florida, 2012.; Includes bibliographical references (p. 109-118).
M.S.
Masters
Physics
Sciences
Physics

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18

OCANA, ORTIZ ROSA-VIRGINI. "La reorganisation du systeme de transport collectif de surface a caracas a partir de la mise en service du metro." Paris 12, 1993. http://www.theses.fr/1993PA120010.

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Le service de transport collectif urbain de caracas correspond a un marche concurrentiel ou des nouveaux modes de transport ont ete introduits a partir de 1983 : le metro, puis les autobus de la compagnie du metro. Ces deux nouvelles composantes de l'offre sont venues modifier le systeme de transport collectif urbain, sans le casser. Ils ont occasionne des changements sur les divers modes de transport collectif sur les "por puestos", les autobus et les jeeps. Cependant, bien que ces changements mettent en cause les caracteristiques du systeme (introduction d'une nouvelle technologie), ils ne changent pas les logiques du systeme. L'introduction du metro et des "metrobus" n'ont provoque qu'une nouvelle repartition du marche et un reajustement dans l'offre de transport. L'objet de cette these est donc de connaitre la transformation de l'offre de transport collectif urbain de caracas apres la mise en service du metro et de comprendre pourquoi l'integration des differents modes de transport collectif urbain a ete impossible
The caracas public transport service is merged into a competitive market in which new transport modes have been introduced since 1983 : the metropolitan, followed by the buses of the metropolitan railway company. The purpose of this thesis is to know about the transformation in the caracas public transport offer after the inauguration of the metropolitan railway, and to understand why the integration of the various public transport modes has been impossible

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19

Zhang, Fan. "A NEW PARADIGM OF MODELING WATERSHED WATER QUALITY." Doctoral diss., University of Central Florida, 2005. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2387.

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Accurate models to reliably predict sediment and chemical transport in watershed water systems enhance the ability of environmental scientists, engineers and decision makers to analyze the impact of contamination problems and to evaluate the efficacy of alternative remediation techniques and management strategies prior to incurring expense in the field. This dissertation presents the conceptual and mathematical development of a general numerical model simulating (1) sediment and reactive chemical transport in river/stream networks of watershed systems; (2) sediment and reactive chemical transport in overland shallow water of watershed systems; and (3) reactive chemical transport in three-dimensional subsurface systems. Through the decomposition of the system of species transport equations via Gauss-Jordan column reduction of the reaction network, fast reactions and slow reactions are decoupled, which enables robust numerical integrations. Species reactive transport equations are transformed into two sets: nonlinear algebraic equations representing equilibrium reactions and transport equations of kinetic-variables in terms of kinetically controlled reaction rates. As a result, the model uses kinetic-variables instead of biogeochemical species as primary dependent variables, which reduces the number of transport equations and simplifies reaction terms in these equations. For each time step, we first solve the advective-dispersive transport of kinetic-variables. We then solve the reactive chemical system node by node to yield concentrations of all species. In order to obtain accurate, efficient and robust computations, five numerical options are provided to solve the advective-dispersive transport equations; and three coupling strategies are given to deal with the reactive chemistry. Verification examples are compared with analytical solutions to demonstrate the numerical accuracy of the code and to emphasize the need of implementing various numerical options and coupling strategies to deal with different types of problems for different application circumstances. Validation examples are presented to evaluate the ability of the model to replicate behavior observed in real systems. Hypothetical examples with complex reaction networks are employed to demonstrate the design capability of the model to handle field-scale problems involving both kinetic and equilibrium reactions. The deficiency of current practices in the water quality modeling is discussed and potential improvements over current practices using this model are addressed.
Ph.D.
Department of Civil and Environmental Engineering
Engineering and Computer Science
Civil Engineering

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Smar, Daina. "An assessment of ecological processes in the Apalachicola estuarine system, Florida." Master's thesis, University of Central Florida, 2012. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5506.

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The following is a compilation of field data collected in 2011 and 2012 in Apalachicola, FL as part of a five year study assessing the ecological effects of sea level rise in the northern Gulf of Mexico. Many coastal communities, both natural and developed, will soon be working to mitigate the effects of sea level rise, if they are not already doing so. This thesis investigates the natural patterns of the Apalachicola estuarine system through the collection and analysis of in situ water, sediment, and biomass samples. Additionally, results of the field samples are presented and recommendations for additional sampling are given. The field methods and procedures developed in this study were designed to be repeated in other estuaries to build upon the work that has been conducted in Apalachicola. Water samples were tested for total suspended solids (TSS) and compared against hydrodynamic (tidal circulation and streamflow) and meteorological (wind and precipitation) characteristics. Streamflow was determined to influence a seasonal base level concentration of TSS. Wind strength and direction consistently influenced small TSS concentration fluctuations, an effect amplified by the shallow nature of the estuary. Tidal circulation appeared to have minor influences on TSS concentration fluctuations within the base level concentration range. Precipitation appeared to influence large TSS concentration fluctuations; however, due to limited data collection during storm events, more data is required to conclusively state this. Sediment cores throughout the lower Apalachicola River revealed that coarse particles settled out in upstream areas while fine particles tended to stay in suspension until low energy areas in the lower portions of the river or marsh system were reached. Finally, biomass samples were used to develop regression models utilizing remotely sensed data to predict biomass density in marsh areas with unprecedented accuracy. The documented patterns of this system are to be used as inputs and validation points to update an existing hydrodynamic model and to aid in the coupling and development of sediment transport and marsh equilibrium models. The field campaign developed and implemented here provides a foundation for this novel coupled modeling effort of estuarine systems. From the 2011 and 2012 sampling conducted, it is apparent that Apalachicola can be modeled as a closed system with river inflow and sediment influx as boundary conditions. Forcing local conditions should accurately represent the system. Ultimately, these models will be used to simulate future sea level rise scenarios and will provide useful decision making tools to coastal managers. Future work will include replicating water sampling in subsequent wet and dry seasons in Apalachicola, FL to confirm observed trends, in addition to implementing this sampling in Grand Bay, MS and Weeks Bay, AL. Additional biomass samples will be taken to validate the strong correlations found between remotely sensed data and in situ samples. In similar studies, it is recommended that water samples be taken to adequately represent influences from tidal cycles and riverine inflow. It is also recommended that spatially distributed biomass samples be taken to validate regression models.
M.S.
Masters
Civil, Environmental, and Construction Engineering
Engineering and Computer Science
Civil Engineering; Water Resources Engineering

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21

Prelipcean, Adrian Corneliu. "Capturing travel entities to facilitate travel behaviour analysis : A case study on generating travel diaries from trajectories fused with accelerometer readings." Licentiate thesis, KTH, Geodesi och geoinformatik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-187491.

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The increase in population, accompanied by an increase in the availability of travel opportunities have kindled the interest in understanding how people make use of the space around them and their opportunities. Understanding the travel behaviour of individuals and groups is difficult because of two main factors: the travel behaviour's wide coverage, which encompasses different research areas, all of which model different aspects of travel behaviour, and the difficulty of obtaining travel diaries from large groups of respondents, which is imperative for analysing travel behaviour and patterns. A travel diary allows an individual to describe how she performed her activities by specifying the destinations, purposes and travel modes occurring during a predefined period of time. Travel diaries are usually collected during a large-scale survey, but recent developments show that travel diaries have important drawbacks such as the collection bias and the decreasing response rate. This led to a surge of studies that try to complement or replace the traditional declaration-based travel diary collection with methods that extract travel diary specific information from trajectories and auxiliary datasets. With the automation of travel diary generation in sight, this thesis presents a suitable method for collecting data for travel diary automation (Paper I), a framework to compare multiple travel diary collection systems (Paper II), a set of relevant metrics for measuring the performance of travel mode segmentation methods (Paper III), and applies these concepts during different case studies (Paper IV).

QC 20160525

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Prud'homme, Julie. "Estimation et analyse spatiales des émissions de polluants de transports individualisés : évaluation des performances environnementales d'un Transport à la Demande." Phd thesis, Université d'Avignon, 2013. http://tel.archives-ouvertes.fr/tel-00992326.

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Le Transport A la Demande (TAD) est un système de transport qui propose un usage collectif des véhicules automobiles, par opposition à l'usage des véhicules personnels (VP). Situé entre le fonctionnement des taxis et celui des transports en commun classiques, il propose un service à la fois flexible dans le temps et dans l'espace à la manière des taxis, favorisant le partage des véhicules, comme les transports en commun. Il est ainsi présenté comme une réponse pour une mobilité durable. Dans les esprits, les TAD sont souvent associés à une réduction des émissions de polluants et sont mis en place principalement dans des territoires ruraux. Pourtant, le simple regroupement effectué par les TAD suffit-il pour que la mise en place des TAD soit profitable à l'environnement ? Dans ce travail de recherche de doctorat, un outil d'évaluation de l'impact environnemental d'un système de Transports À la Demande (TAD) destiné aux collectivités territoriales a été mis au point. Pour que choix soit durable, au sens du développement durable, le service doit être le plus adapté au contexte local en minimisant les émissions de substances dans l'atmosphère proche tout en conservant une qualité de service suffisante pour concurrencer l'usage du véhicule personnel. Un paramètre, directement impliqué dans les émissions de polluant, est souvent négligé dans les approches : le réseau routier. On cherche donc à identifier des lois et des seuils relatifs aux émissions de polluants produites par le fonctionnement d'un TAD : dans quelle mesure le réseau routier influe-t-il sur les performances environnementales des TAD ou sur la capacité de regroupement des clients dans les véhicules ? Selon quelles caractéristiques de service (fenêtres de temps autorisées) ? Plus globalement, est-ce que l'optimisation d'un même type de TAD est équivalente d'un réseau routier à un autre, du point de vue des émissions de polluants ? Aucun outil intégré permettant d'effectuer cette tâche n'étant disponible, nous avons mis au point une chaîne de traitement géomatique permettant d'estimer les quantités de polluants émises sur les tronçons de route dans le cadre du fonctionnement particulier des TAD et de les cartographier pour analyser leur répartition spatiale. Cet outil associe un SIG à un modèle d'émission que nous avons adapté à notre problématique (GREEN-DRT). Il est ressorti des différents scénarios simulés que les TAD ne sont pas systématiquement une solution pertinente dans un objectif de réduction globale des émissions de polluants sur un territoire donné. Le constat de la faible pertinence environnementale de ce mode de transport sur les territoires les moins denses (type zones rurales) a été fait, pourtant, ce sont sur ces territoires que les TAD sont développés en France. À défaut d'engendrer une réduction des émissions, ils ont souvent un rôle social important en se positionnant non pas comme une alternative à la voiture personnelle, mais en permettant à des populations captives de se déplacer. Il s'agit de ce cas de minimiser les émissions de polluants provoquées par le fonctionnement du service.

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23

Xu, Jin. "Un modèle multi-agent distribué et hybride pour la planification du transport à la demande temps réel." Phd thesis, INSA de Rouen, 2008. http://tel.archives-ouvertes.fr/tel-00558769.

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Durant ces dernières années, la congestion du trafic urbain et la pollution de l'air sont devenus d'énormes problèmes dans de nombreuses villes dans le monde. Afin de réduire cette congestion, nous pouvons investir dans l'amélioration des infrastructures de la ville. Toutefois, cette solution reste très coûteuse à entreprendre et de ne permet pas de réduire la pollution de l'air. C'est pourquoi nous travaillons sur la mobilité intelligente afin de disposer d'une meilleure utilisation de la voiture. L'application de nouvelles technologies de l'information, tels que les systèmes multi-agents appliqués au contrôle de l'information de la circulation urbaine, a permis de créer et de déployer une gestion plus intelligente du trafic comme le système DRT (transport à la demande). L'objectif des systèmes multi-agents basés sur le DRT est de gérer les taxis de manière intelligente, afin d'accroître le nombre de passagers dans chaque véhicule, et en même temps à réduire le nombre de véhicules dans les rues. Cela permettra de réduire les émissions de CO2 et la pollution de l'air causée par les véhicules, ainsi que la congestion du trafic et les coûts financiers associés. La simulation multi-agents est considérée comme un outil efficace pour les services dynamiques urbains de la circulation. Toutefois, le principal problème est de savoir comment construire un agent à base de modèle pour cette problématique. Ces travaux de recherche présente une solution basée sur les systèmes multi-agents réactifs pour la problématique du transport à la demande (DRT), qui adopte une approche multi-agent de planification urbaine en utilisant des services de contrôle qui satisfont aux principales contraintes : réduction de la période totale creuse, demandes spéciales du client, augmentation du nombre de places utilisées dans un même taxi, utilisation du nombre minimal de véhicules, etc. Dans cette thèse, nous proposons un modèle multi-agents multicouche hybride distribué pour des problématiques en temps réel. Dans la méthode proposée, un agent pour chaque véhicule trouve un ensemble de routes pour sa recherche locale, et choisit un itinéraire en coopérant avec d'autres agents se trouvant dans son domaine de planification. Nous avons examiné expérimentalement, l'efficacité de la méthode proposée.

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Cheifetz, Nicolas. "Détection et classification de signatures temporelles CAN pour l’aide à la maintenance de sous-systèmes d’un véhicule de transport collectif." Thesis, Paris Est, 2013. http://www.theses.fr/2013PEST1077/document.

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Le problème étudié dans le cadre de cette thèse porte essentiellement sur l'étape de détection de défaut dans un processus de diagnostic industriel. Ces travaux sont motivés par la surveillance de deux sous-systèmes complexes d'un autobus impactant la disponibilité des véhicules et leurs coûts de maintenance : le système de freinage et celui des portes. Cette thèse décrit plusieurs outils dédiés au suivi de fonctionnement de ces deux systèmes. On choisit une approche de diagnostic par reconnaissance des formes qui s'appuie sur l'analyse de données collectées en exploitation à partir d'une nouvelle architecture télématique embarquée dans les autobus. Les méthodes proposées dans ces travaux de thèse permettent de détecter un changement structurel dans un flux de données traité séquentiellement, et intègrent des connaissances disponibles sur les systèmes surveillés. Le détecteur appliqué aux freins s'appuie sur les variables de sortie (liées au freinage) d'un modèle physique dynamique du véhicule qui est validé expérimentalement dans le cadre de nos travaux. L'étape de détection est ensuite réalisée par des cartes de contrôle multivariées à partir de données multidimensionnelles. La stratégie de détection pour l'étude du système porte traite directement les données collectées par des capteurs embarqués pendant des cycles d'ouverture et de fermeture, sans modèle physique a priori. On propose un test séquentiel à base d'hypothèses alimenté par un modèle génératif pour représenter les données fonctionnelles. Ce modèle de régression permet de segmenter des courbes multidimensionnelles en plusieurs régimes. Les paramètres de ce modèle sont estimés par un algorithme de type EM dans un mode semi-supervisé. Les résultats obtenus à partir de données réelles et simulées ont permis de mettre en évidence l'efficacité des méthodes proposées aussi bien pour l'étude des freins que celle des portes
This thesis is mainly dedicated to the fault detection step occurring in a process of industrial diagnosis. This work is motivated by the monitoring of two complex subsystems of a transit bus, which impact the availability of vehicles and their maintenance costs: the brake and the door systems. This thesis describes several tools that monitor operating actions of these systems. We choose a pattern recognition approach based on the analysis of data collected from a new IT architecture on-board the buses. The proposed methods allow to detect sequentially a structural change in a datastream, and take advantage of prior knowledge of the monitored systems. The detector applied to the brakes is based on the output variables (related to the brake system) from a physical dynamic modeling of the vehicle which is experimentally validated in this work. The detection step is then performed by multivariate control charts from multidimensional data. The detection strategy dedicated to doors deals with data collected by embedded sensors during opening and closing cycles, with no need for a physical model. We propose a sequential testing approach using a generative model to describe the functional data. This regression model allows to segment multidimensional curves in several regimes. The model parameters are estimated via a specific EM algorithm in a semi-supervised mode. The results obtained from simulated and real data allow to highlight the effectiveness of the proposed methods on both the study of brakes and doors

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Ekström, Joakim. "Designing Urban Road Congestion Charging Systems : Models and Heuristic Solution Approaches." Licentiate thesis, Linköping University, Department of Science and Technology, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-15747.

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The question of how to design a congestion pricing scheme is difficult to answer and involves a number of complex decisions. This thesis is devoted to the quantitative parts of designing a congestion pricing scheme with link tolls in an urban car traffic network. The problem involves finding the number of tolled links, the link toll locations and their corresponding toll level. The road users are modeled in a static framework, with elastic travel demand.

Assuming the toll locations to be fixed, we recognize a level setting problem as to find toll levels which maximize the social surplus. A heuristic procedure based on sensitivity analysis is developed to solve this optimization problem. In the numerical examples the heuristic is shown to converge towards the optimum for cases when all links are tollable, and when only some links are tollable.

We formulate a combined toll location and level setting problem as to find both toll locations and toll levels which maximize the net social surplus, which is the social surplus minus the cost of collecting the tolls. The collection cost is assumed to be given for each possible toll location, and to be independent of toll level and traffic flow. We develop a new heuristic method which is based on repeated solutions of an approximation to the combined toll location and level setting problem. Also, a known heuristic method for locating a fixed number of toll facilities is extended, to find the optimal number of facilities to locate. Both heuristics are evaluated on two small networks, where our approximation procedure shows the best results.

Our approximation procedure is also employed on the Sioux Falls network. The result is compared with different judgmental closed cordon structures, and the solution suggested by our method clearly improves the net social surplus more than any of the judgmental cordons.

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Cano-Viktorsson, Carlos. "From Vision to Transition : Exploring the Potential for Public Information Services to Facilitate Sustainable Urban Transport." Licentiate thesis, KTH, Historiska studier av teknik, vetenskap och miljö, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-143218.

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Background: Policy initiatives to promote sustainable travel through the use of Internet based public information systems have increased during the last decade. Stockholm, in being one of the first cities in Europe to implement an Internet based service for facilitating sustainable travel is believed to be a good candidate for an analysis of key issues for developing sustainable travel planning services to the public. Aim: This thesis investigates the past development of two Stockholm based public information systems and their services in order to draw lessons on how to better provide for a public information service geared towards facilitating environmentally sustainable travel planning through information and communications technology. The overall goal of the thesis is to contribute to an understanding on how to better design and manage current and future attempts at facilitating sustainable travel planning services based on historical case studies. Approach: The thesis draws ideas from the concept of organizational responsiveness – an organization’s ability to listen, understand and respond to demands put to it by its internal and external stakeholders – in order to depict how well or not the two public information systems and their owners have adapted to established norms and values of their surroundings. Results: Overall, the findings from the historical case studies suggest that organizations attempting to provide sustainable travel planning to the public need to design and manage their systems in such a way that it responds to shifting demands on how to provide for information. Implementing and embedding new technologies involves complex processes of change both at the micro level – for users and practitioners of the service – and at the meso level for the involved public service organizations themselves. This condition requires a contextualist framework to analyze and understand organizational, contextual and cultural issues involved in the adoption of new technologies and procedures. Conclusions: The thesis concludes with a discussion on how the findings from the historical case studies may provide lessons for both current and future attempts at providing public information systems geared towards facilitating environmentally sustainable travel planning to the public. Historical examples and issues concerning collective intelligence and peer to peer based forms of designing, producing and supervising public information services identified throughout the study are looked upon and discussed in terms of their possible role in increasing the potential for public information services to facilitate sustainable urban transport.

QC 20140319

TRACS, Travel Planner for Sustainable Cities

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Tirachini, Alejandro. "Multimodal pricing and the optimal design of bus services: new elements and extensions." Thesis, The University of Sydney, 2012. http://hdl.handle.net/2123/8584.

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This thesis analyses the pricing and design of urban transport systems; in particular the optimal design and efficient operation of bus services and the pricing of urban transport. Five main topics are addressed: (i) the influence of considering non-motorised travel alternatives (walking and cycling) in the estimation of optimal bus fares, (ii) the choice of a fare collection system and bus boarding policy, (iii) the influence of passengers’ crowding on bus operations and optimal supply levels, (iv) the optimal investment in road infrastructure for buses, which is attached to a target bus running speed and (v) the characterisation of bus congestion and its impact on bus operation and service design. Total cost minimisation and social welfare maximisation models are developed, which are complemented by the empirical estimation of bus travel times. As bus patronage increases, it is efficient to invest money in speeding up boarding and alighting times. Once on-board cash payment has been ruled out, allowing boarding at all doors is more important as a tool to reduce both users and operator costs than technological improvements on fare collection. The consideration of crowding externalities (in respect of both seating and standing) imposes a higher optimal bus fare, and consequently, a reduction of the optimal bus subsidy. Optimal bus frequency is quite sensitive to the assumptions regarding crowding costs, impact of buses on traffic congestion and congestion level in mixed-traffic roads. The existence of a crowding externality implies that buses should have as many seats as possible, up to a minimum area that must be left free of seats. Bus congestion in the form of queuing delays behind bus stops is estimated using simulation. The delay function depends on the bus frequency, bus size, number of berths and dwell time. Therefore, models that use flow measures (including frequency only or frequency plus traffic flow) as the only explanatory variables for bus congestion are incomplete. Disregarding bus congestion in the design of the service would yield greater frequencies than optimal when congestion is noticeable, i.e. for high demand. Finally, the optimal investment in road infrastructure for buses grows with the logarithm of demand; this result depends on the existence of a positive and linear relationship between investment in infrastructure and desired running speed.

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Malas, Anas. "Contributions à la résolution du transport à la demande fondées sur les systèmes multi-agents." Thesis, Normandie, 2017. http://www.theses.fr/2017NORMIR07/document.

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Cette thèse porte sur le problème du transport à la demande (TAD). Nous proposons trois approches décentralisées basées sur les systèmes multi-agents pour résoudre ce problème. La première approche multi-agent utilise l'algorithme A* afin de trouver une solution optimale dans un réseau routier caractérisé par des vitesses de voyage constantes. Des expérimentations sont effectuées sur le réseau routier d'une ville libanaise appelée Tripoli et de bons résultats sont obtenus. Cependant, dans une ville comme Tripoli, les vitesses de voyage dépendent fortement de la situation dynamique du trafic routier. Pour cette raison, la deuxième approche multi-agent massif vient remédier à la première en tenant compte de l'évolution du trafic. Le réseau routier est considéré comme dynamique déterministe. Il se caractérise par des vitesses de voyages dépendantes de la situation habituelle du trafic. Ces vitesses sont pré-calculées en se basant sur des connaissances historiques du trafic routier. Les résultats expérimentaux montrent que le nombre de clients insatisfaits est supérieur à 50 % si les vitesses sont considérées comme constantes. Or, les connaissances historiques ne suffisent pas pour refléter la situation réelle du trafic surtout en cas d'apparition d'un événement imprévu tel qu'un accident sur le réseau. Pour cela, une troisième approche multi-agent massif auto-organisé est proposée. Le réseau routier est considéré comme dynamique stochastique caractérisé par des vitesses de voyage dépendantes de la situation réelle du trafic. Cette approche représente l'organisation dynamique du trafic à son échelle en se basant sur des connaissances historiques du trafic et sur des informations du trafic en temps réel. Les trajectoires des véhicules et leurs durées sont calculées et recalculées en ligne à chaque fois qu'un événement imprévu perturbe la situation habituelle du trafic. Les résultats expérimentaux montrent que jusqu'à 39 % des clients seront insatisfaits si un accident routier n'est pas considéré durant le traitement de leurs demandes. Autrement, 50 % à 100 % de ces clients sont satisfaits
This thesis addresses the problem of on-demand transport (ODT). We propose three decentralized approaches based on multi-agent systems to solve this problem. The first multi-agent approach uses the algorithm A* in order to find an optimal solution in a road network characterized by constant travel speeds. Experiments are carried out on the road network of a Lebanese city called Tripoli and good results are obtained. However, in a city like Tripoli, travel speeds depend heavily on the dynamic situation of road traffic. For this reason, the second multi-agent approach massif comes to remedy the first taking into account the evolution of traffic. The road network is considered as dynamic deterministic. It is characterized by travel speeds dependent on the usual traffic situation. These speeds are pre-calculated on the basis of historical knowledge of road traffic. The experimental results show that the number of dissatisfied customers is greater than 50 % if the speeds are considered to be constant. Nevertheless, historical knowledge is not sufficient to reflect the actual traffic situation, especially in case of an unexpected event (such as an accident) occurring on the network. For this, a self-organized massive multi-agent approach is proposed. The road network is considered as a dynamic stochastic characterized by travel speeds dependent on the actual traffic situation. This approach represents the dynamic organization of traffic on its scale based on historical traffic knowledge and real-time traffic information. Vehicle trajectories and their durations are calculated and recalculated online whenever an unexpected event disrupts the usual traffic situation. The experimental results show that up to 39 % of customers will be dissatisfied if a road accident is not considered during the processing of their demands. Otherwise, 50 % to 100 % of these customers are satisfied

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LAGRÉE, PAUL. "Crowdsourcing public transport data via livemobile tracking : Feasibility study of a system capable of collecting mobile data to build a database ofpublic transit routes, stops and timetables, using machine learning techniques andgraph theory." Thesis, KTH, Skolan för datavetenskap och kommunikation (CSC), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-153677.

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Millions of people use public transport systems everywhere in the world, while the number of smartphones connected to the Internet is dramatically increasing. The aim of this thesis is to study, design, and prototype a system to collect data from the mobile devices of regular public transport users and analyse them in order to provide useful information to travellers all over the world. To study the feasibility of this project at a large scale, data will be created to simulate what will be collected via mobile phone applications. The main objective of this paper is to study the effect of data mining techniques on mapping original transport routes with associated timetables.
Crowdsourcing av kollektivtrafikdata via direkt mobilspårning. Miljontals personer använder kollektivtrafik överallt i världen och antalet smartphones med internetanslutning stiger dagligen. Avsikten med den här avhandlingen är att undersöka, skapa och testa ett system som samlar och analyserar data från mobiltelefoner av kollektivtrafikanvändare så att användbar information kan bli tillgänglig till resande världen över. För att generellt undersöka möjligheten med ett sådant projekt kommer data att skapas för att simulera informationen som är tänkt att senare samlas från resandes mobiletelefoner. Huvudsyftet med den här avhandlingen är att undersöka data mining effekter i kartläggningen av ursprungliga transportsträckor och dess tidtabeller.

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Zidi, Issam. "Modélisation et Optimisation d’un Système de Transport à la Demande Multicritère et Dynamique." Thesis, Ecole centrale de Lille, 2012. http://www.theses.fr/2012ECLI0012/document.

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Le Problème de Transport à la Demande (PTD), consiste à prendre en charge le transport des personnes d'un lieu de départ vers un lieu d'arrivée. Il est caractérisé par un ensemble de demandes de transport et d'un nombre de véhicules disponible. L'ultime objectif dans ce travail de thèse est d'offrir une alternative optimisée au déplacement individuel et collectif. Le PTD est classé parmi les problèmes NP-difficile, la majorité des travaux de recherche ont été concentrés sur l'utilisation des méthodes approchées pour le résoudre.Ce problème est également multicritère, la solution proposée dans ce travail permet à la fois une réduction du temps de voyage et également de la distance parcourue. Dans cette thèse, nous proposons notre contribution à l'étude et à la résolution du problème de transport à la demande multicritère et dynamique en appliquant l'algorithme de recuit simulé multi-objectif. Une grande partie de notre travail concerne la conception, le développement et la validation des approches qui permettent de donner des solutions optimales ou quasi optimales, pour un PTD. Ces approches utilisent une méthode multicritère qui s’appuie sur l’algorithme de recuit simulé. La modélisation du PTD est représentée par une architecture multi-acteurs. Cette architecture met en évidence l’aspect distribué du système ainsi que les interactions et les relations qui peuvent avoir lieu entre les différents acteurs. Nous présentons dans ce travail un Système Multi-Agents pour la planification des itinéraires des véhicules affectés au transport des voyageurs. Les agents de ce système utilisent le module d’optimisation développé dans la première partie
The Dial a Ride Problem (DRP) is to take passengers from a place of departures to places of arrivals. Different versions of the dynamic Dial a Ride Problem are found in every day practice; transportation of people in low-density areas, transportation of the handicapped and elderly persons and parcel pick-up and delivery service in urban areas. In the DRP, customers send transportation requests to an operator. A request consists of a specified pickup location and destination location along with a desired departure or arrival time. The ultimate aim is to offer an alternative to displacement optimized individually and collectively. The DRP is classified as NP-hard problem that’s why most research has been concentrated on the use of approximate methods to solve it. Indeed the DRP is a multi-criteria problem, the proposed solution of which aims to reduce both route duration in response to a certain quality of service provided. In this thesis, we offer our contribution to the study and solving the DRP in the application using a multi agent system based on the Multi-Objective Simulated Annealing Algorithm

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Moura, Delmo Alves de. "Caracterização e análise de um sistema de coleta programada de peças, Milk Run, na indústria automobilística nacional." Universidade de São Paulo, 2000. http://www.teses.usp.br/teses/disponiveis/3/3135/tde-29102001-122751/.

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O objetivo deste trabalho é caracterizar e analisar um novo sistema de abastecimento de suprimentos que está sendo adotado por diversas indústrias automobilísticas nacionais, denominado Milk Run. Este sistema consiste na coleta programada de peças junto aos fornecedores das montadoras, e diferentemente do sistema de abastecimento denominado Convencional, no qual o fornecedor entrega suas peças na planta da montadora. A análise visa estudar se existirá redução de estoque na cadeia de suprimentos com o novo sistema implantado, quais os custos pertinentes a esta nova técnica, qual o papel do fornecedor, da montadora e do operador logístico (transportadora) no novo processo e suas vantagens em relação ao sistema Convencional. Para levantamento do problema em estudo, a adoção do sistema Milk Run, foram realizadas visitas nas indústrias automobilísticas nacionais. Alguns fornecedores, que participam deste sistema, também foram visitados para compreender como, na prática, é realizada a coleta programada, suas vantagens e desvantagens. Operadores logísticos, que executam a operação de transporte para as montadoras também foram visitado. Esta dissertação visa relatar que o sistema Milk Run adota uma concepção de trabalho com enorme ênfase na filosofia Just-in-Time, e procura seguir alguns de seus princípios como: redução do estoque de materiais, maior freqüência de abastecimento de suprimentos e maior integração entre as partes que compõem o sistema, montadora e fornecedor. A contribuição deste trabalho está em caracterizar e analisar o novo sistema, Milk Run, e propor uma comparação dos custos da nova abordagem, com os custos pertinentes ao sistema Convencional (no qual os fornecedores entregam suas peças diretamente na planta da montadora). Esta comparação baseia-se nos custos definidos pelas literaturas em função do tamanho do lote de aquisição de peças e uma análise de Trade-offs entre as variáveis destes sistemas em função da flutuação da demanda anual. No sistema Milk Run em estudo será utilizado o Kanban como ferramenta de gerenciamento de requisição de peças.
The objective of this dissertation is to feature and analyse the new systems of procurement in Brazilian vehicle industry called Milk Run. This study compares Milk Run, which is a scheduled pick up automobile parts program, picking up automobile parts from several suppliers and returning the reusable containers to suppliers, to Conventional system of procurement (each supplier delivery its automobile parts in the vehicle assembly plant). The analysis is to study the inventory cost in both cases Milk Run and Conventional systems. Another analysis is to understand the role of the supplier, automaker and the logistic provider in Milk Run system and its advantages. Many visits have been necessary to the automakers, suppliers and logistics providers to understand this new situation in Brazil. This dissertation shows that Milk Run system is very close to Just-in-Time system and adopt the same philosophy as: reduction of inventory, increase frequency supply and increase integration between both parts, automaker and supplier. This dissertation tries to contribute to understand the costs included in both system and propose a modeling to compare the costs inherent in Milk Run and Conventional system. This modeling uses the costs defined in the literature about inventory and transportation system depending on the shipment size and one analysis of the Trade-offs in both systems.

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Simões, Carlos Enrique Hernández. "Geovisualização analítica: desenvolvimento de um protótipo de um sistema analítico de informações para a gestão da coleta seletiva de resíduos urbanos recicláveis." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/3/3138/tde-17082010-111747/.

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Os resíduos urbanos descartados de forma irregular constituem um problema sério, principalmente nas grandes cidades, causando entupimento de bueiros e drenagem com conseqüentes inundações, sujeira e transmissão de doenças tais como leptospirose e dengue além de ser um estorvo para o trânsito e acarretarem gastos para a Prefeitura. Por outro lado, reciclar este material é uma fonte de receitas e um gerador de empregos. A Geovisualização Analítica pode ser de grande auxílio para a análise desse problema complexo e para a tomada de decisão. Com essa motivação, a presente dissertação procura fornecer uma visão geral sobre o estado da arte quanto a conceitos e pesquisas em Geovisualização (GVis) e Processamento Analítico (OLAP e SOLAP). Apresenta também processos, metodologias e tecnologias que foram utilizadas no desenvolvimento de um protótipo de um sistema analítico de informações aplicado à área de gestão da coleta seletiva de resíduos sólidos recicláveis em ambiente urbano. Este protótipo, efetivamente implantado, combinou navegação e consulta para recuperar informações através de seleções espaciais e alfanuméricas. Através de exemplos foi mostrado que este tipo de solução auxilia gestores nos processos de exploração, análise e tomada de decisão.
Domestic waste illegally disposed constitute a serious problem, especially in large cities, causing clogging of drains and drainage with subsequent flooding, dirt and transmission of diseases such as leptospirosis and dengue as well as being a hindrance to traffic and would entail city hall costs. Moreover, recycle this material is a source of revenue and a generator of jobs. The Analytical Geovisualization can be of great help in the analysis of this complex problem and the decision-making. With this motivation, this paper seeks to provide an overview of the state of the art as the concepts and research in Geovisualization (GVis) and Analytical Processing (OLAP and SOLAP). It also presents processes, methodologies and technologies that were used in developing a prototype of an analytical system applied to the area of selective collection information management of recyclable solid waste in urban environments. This prototype, effectively deployed, combined navigation and query to retrieve information through spatial and alphanumeric selections. Through examples it was shown that this type of solution helps managers in operating procedures, analysis and decision making.

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Geier, Kevin Thomas. "Probing Dynamics and Correlations in Cold-Atom Quantum Simulators." Doctoral thesis, Università degli studi di Trento, 2022. http://hdl.handle.net/11572/351120.

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Cold-atom quantum simulators offer unique possibilities to prepare, manipulate, and probe quantum many-body systems. However, despite the high level of control in modern experiments, not all observables of interest are easily accessible. This thesis aims at establishing protocols to measure currently elusive static and dynamic properties of quantum systems. The experimental feasibility of these schemes is illustrated by means of numerical simulations for relevant applications in many-body physics and quantum simulation. In particular, we introduce a general method for measuring dynamical correlations based on non-Hermitian linear response. This enables unbiased tests of the famous fluctuation-dissipation relation as a probe of thermalization in isolated quantum systems. Furthermore, we develop ancilla-based techniques for the measurement of currents and current correlations, permitting the characterization of strongly correlated quantum matter. Another application is geared towards revealing signatures of supersolidity in spin-orbit-coupled Bose gases by exciting the relevant Goldstone modes. Finally, we explore a scenario for quantum-simulating post-inflationary reheating dynamics by parametrically driving a Bose gas into the regime of universal far-from-equilibrium dynamics. The presented protocols also apply to other analog quantum simulation platforms and thus open up promising applications in the field of quantum science and technology.
I simulatori quantistici ad atomi freddi offrono possibilità uniche per preparare, manipolare e sondare sistemi quantistici a molti corpi. Tuttavia, nonostante l'alto livello di controllo raggiunto negli esperimenti moderni, non tutte le osservabili di interesse sono facilmente accessibili. Lo scopo di questa tesi è quello di stabilire protocolli per misurare delle proprietà statiche e dinamiche dei sistemi quantistici attualmente inaccessibili. La fattibilità sperimentale di questi schemi è illustrata mediante simulazioni numeriche per applicazioni rilevanti nella fisica a molti corpi e nella simulazione quantistica. In particolare, introduciamo un metodo generale per misurare le correlazioni dinamiche basato su una risposta lineare non hermitiana. Ciò consente test imparziali della famosa relazione fluttuazione-dissipazione come sonda di termalizzazione in sistemi quantistici isolati. Inoltre, sviluppiamo tecniche basate su ancilla per la misura di correnti e correlazioni di corrente, consentendo la caratterizzazione della materia quantistica fortemente correlata. Un'altra applicazione è orientata a rivelare l'impronta della supersolidità nei gas Bose con accoppiamento spin-orbita eccitando il corrispondente modo di Goldstone. Infine, esploriamo uno scenario per la simulazione quantistica della dinamica di riscaldamento post-inflazione modulando parametricamente un gas Bose e portandolo nel regime della dinamica universale lontana dall'equilibrio. I protocolli presentati si applicano anche ad altre piattaforme di simulazione quantistica analogica e aprono quindi applicazioni promettenti nel campo della scienza e della tecnologia quantistica.
Quantensimulatoren auf Basis ultrakalter Atome eröffnen einzigartige Möglichkeiten zur Präparation, Manipulation und Untersuchung von Quanten-Vielteilchen-Systemen. Trotz des hohen Maßes an Kontrolle in modernen Experimenten sind jedoch nicht alle interessanten Observablen auf einfache Weise zugänglich. Ziel dieser Arbeit ist es, Protokolle zur Messung aktuell nur schwer erfassbarer statischer und dynamischer Eigenschaften von Quantensystemen zu etablieren. Die experimentelle Realisierbarkeit dieser Verfahren wird durch numerische Simulationen anhand relevanter Anwendungen in der Vielteilchenphysik und Quantensimulation veranschaulicht. Insbesondere wird eine allgemeine Methode zur Messung dynamischer Korrelationen basierend auf der linearen Antwort auf nicht-hermitesche Störungen vorgestellt. Diese ermöglicht unabhängige Tests des berühmten Fluktuations-Dissipations-Theorems als Indikator der Thermalisierung isolierter Quantensysteme. Darüber hinaus werden Verfahren zur Messung von Strömen und Strom-Korrelationen mittels Kopplung an einen Hilfszustand entwickelt, welche die Charakterisierung stark korrelierter Quantenmaterie erlauben. Eine weitere Anwendung zielt auf die Enthüllung spezifischer Merkmale von Supersolidität in Spin-Bahn-gekoppelten Bose-Einstein-Kondensaten ab, indem die relevanten Goldstone-Moden angeregt werden. Schließlich wird ein Szenario zur Quantensimulation post-inflationärer Thermalisierungsdynamik durch die parametrische Anregung eines Bose-Gases in das Regime universeller Dynamik fern des Gleichgewichts erschlossen. Die dargestellten Protokolle lassen sich auch auf andere Plattformen für analoge Quantensimulation übertragen und eröffnen damit vielversprechende Anwendungen auf dem Gebiet der Quantentechnologie.

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Randriamasy, Malalatiana. "Localisation et transmissions sécurisées pour la communication Véhicule à Infrastructure (V2I) : Application au service de télépéage ITS-G5." Thesis, Normandie, 2019. http://www.theses.fr/2019NORMR011/document.

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La localisation précise des véhicules et la sécurité des échanges sont deux grands axes qui font la fiabilité des services fournis dans les systèmes de transport intelligent. Ces dernières années, elles font l’objet de nombreux projets de recherche pour des champs d’application divers. Dans cette thèse, le contexte d’application est la réalisation d’un service de télépéage utilisant la technologie ITS-G5. Cette technologie de communication sans-fil permet dans un premier temps le partage des informations de sécurité routière entre les véhicules (V2V), le véhicule et l’infrastructure (V2I). Dans cette thèse, on propose une architecture permettant d’échanger des transactions de télépéage utilisant les équipements communicants en ITS-G5 embarqués dans les véhicules connectés et les unités bord de route (UBR) de l’infrastructure. Les problématiques de nos travaux de recherche se concentrent sur la méthode de localisation des véhicules ayant effectué la transaction afin de pouvoir la valider et sur la sécurité de l’architecture proposée pour assurer l’échange de cette transaction. Afin de bien localiser les véhicules lors du passage au péage, notre approche propose la compréhension de la cinématique du véhicule par une modélisation adéquate à partir des données recueillies dans les messages coopératifs (CAM : Cooperative Awareness Message) en approche du péage. Cela améliorera les informations de géolocalisation déjà présentes. Notre objectif est d’arriver à une précision de moins d’un mètre pour distinguer 2 véhicules adjacents. D’autre part, le protocole de sécurité proposé permet d’assurer l’authentification des équipements participant à l’échange et à la validation de la transaction, l’intégrité des données échangées ainsi que la confidentialité des échanges compte tenu du contexte de communication sans-fil et de la sensibilité des données échangées. Une preuve de concept de la solution de télépéage utilisant la technologie ITS-G5 est développée et intègre nos deux contributions
The precise localization of vehicles and the security of communication are requirements that make almost of the services provided in intelligent transport systems (ITS) more reliable. In recent years, they have been the subject of numerous research projects for various fields of application. In this thesis, the context is the development of an electronic toll service using the ITS-G5 technology. This wireless communication technology initially allows the sharing of traffic safety information between vehicles (V2V), vehicle and infrastructure (V2I). In our work, we propose a tolling application using equipment operating in ITS-G5 embedded in the connected vehicles and roadside units. For this, ensuring both precise geolocation of the vehicles and security of communication are required to validate the transaction.In order to properly locate the vehicles during the toll crossing, our approach is based on the understanding of the kinematics of the vehicle through a suitable modeling from the data collected in the cooperative messages (called CAM: Cooperative Awareness Message). This approach aims to improve the geolocation information already present in the message. Our goal is to achieve vehicle localization with an accuracy lower than one meter to distinguish two adjacent vehicles. On the other hand, the proposed tolling protocol ensures the authentication of the equipment or entities involved in the exchange and the validation of the transaction, the integrity of the transmitted data as well as the confidentiality of the communication. In this way, we take into account the context of the wireless communication and the sensitivity of the exchanged data. Our two contributions are integrated in the implemented Proof of Concept of the tolling application using the ITS-G5 technology

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Laborde, Maxime. "Systèmes de particules en interaction, approche par flot de gradient dans l'espace de Wasserstein." Thesis, Paris Sciences et Lettres (ComUE), 2016. http://www.theses.fr/2016PSLED014/document.

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Depuis l’article fondateur de Jordan, Kinderlehrer et Otto en 1998, il est bien connu qu’une large classe d’équations paraboliques peuvent être vues comme des flots de gradient dans l’espace de Wasserstein. Le but de cette thèse est d’étendre cette théorie à certaines équations et systèmes qui n’ont pas exactement une structure de flot de gradient. Les interactions étudiées sont de différentes natures. Le premier chapitre traite des systèmes avec des interactions non locales dans la dérive. Nous étudions ensuite des systèmes de diffusions croisées s’appliquant aux modèles de congestion pour plusieurs populations. Un autre modèle étudié est celui où le couplage se trouve dans le terme de réaction comme les systèmes proie-prédateur avec diffusion ou encore les modèles de croissance tumorale. Nous étudierons enfin des systèmes de type nouveau où l’interaction est donnée par un problème de transport multi-marges. Une grande partie de ces problèmes est illustrée de simulations numériques
Since 1998 and the seminal work of Jordan, Kinderlehrer and Otto, it is well known that a large class of parabolic equations can be seen as gradient flows in the Wasserstein space. This thesis is devoted to extensions of this theory to equations and systems which do not have exactly a gradient flow structure. We study different kind of couplings. First, we treat the case of nonlocal interactions in the drift. Then, we study cross diffusion systems which model congestion for several species. We are also interested in reaction-diffusion systems as diffusive prey-predator systems or tumor growth models. Finally, we introduce a new class of systems where the interaction is given by a multi-marginal transport problem. In many cases, we give numerical simulations to illustrate our theorical results

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Elleuch, Fatma. "Transférabilité d'une modélisation-simulation multi-agents : le comportement inter-gares des voyageurs de la SNCF lors des échanges quai-train." Thesis, Paris, CNAM, 2019. http://www.theses.fr/2019CNAM1227/document.

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Les travaux de cette thèse portent sur la définition et la validation d’une méthode de modélisation-simulation de foule permettant le transfert des principes et des mesures établis dans un contexte source d'observations vers des contextes cibles, non observables a priori. A partir de l'observation de comportements de piétons d’un contexte environnemental, social et urbain, nous inférons les règles et des motivations, rendant possible la modélisation et la simulation du comportement individuel de piétons dans ce contexte source, puis à évaluer la transférabilité du modèle dans un autre contexte cible. Nous appuyons nos travaux sur un cas réel. Il s’agit de la simulation du comportement des voyageurs entrants et sortants des trains dans une gare à fort trafic. Après une revue des théories, de modèles de simulation, nous retenons une approche basée sur la simulation microscopique d’agents sociaux, situés, basée sur les motivations. Nous argumentons le choix par le fait que, par rapport à une simulation de foule classique elle, a priori, l’avantage de favoriser la transférabilité. L’objectif de cette simulation est d’étudier, entre autres, les évolutions architecturales des stations permettant de raccourcir les temps d’arrêt des trains
This thesis focuses on the definition and the validation of a crowd-simulation modeling method. This method allows transferring principles and measurements established in a source observation context to a target one. From the observation of pedestrian behavior in a social and urban context, our approach infers rules and motivations in order to model and simulate the individual pedestrian behavior in this source context. This allows, in a second step, to evaluate the transferability of the model to a given target context. Our work is based on a real case: the simulation of the passenger’s behavior while boarding and alighting trains (platform-train exchange) in a high-traffic station (dense situation). Starting from the state of the art of theories, models and types of simulation, we choose an approach based on the microscopic simulation of social agent’s motivation. This choice relies mainly on the fact that, compared to a classic crowd simulation, it has, a priori, a better transferability potential. The goal of this type of simulation is to study the architectural evolutions of the stations that could allow to control or shorten train dwell times

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Belfkih, Abderrahmen. "Contraintes temporelles dans les bases de données de capteurs sans fil." Thesis, Le Havre, 2016. http://www.theses.fr/2016LEHA0014/document.

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Dans ce travail, nous nous focalisons sur l’ajout de contraintes temporelles dans les Bases de Données de Capteurs Sans Fil (BDCSF). La cohérence temporelle d’une BDCSF doit être assurée en respectant les contraintes temporelles des transactions et la validité temporelle des données, pour que les données prélevées par les capteurs reflètent fidèlement l’état réel de l’environnement. Cependant, les retards de transmission et/ou de réception pendant la collecte des données peuvent conduire au non-respect de la validité temporelle des données. Une solution de type bases de données s'avère la plus adéquate. Il faudrait pour cela faire coïncider les aspects BD traditionnelles avec les capteurs et leur environnement. À cette fin, les capteurs déployés au sein d'un réseau sans fils sont considérés comme une table d'une base de données distribuée, à laquelle sont appliquées des transactions (interrogations, mises à jour, etc.). Les transactions sur une BD de capteurs nécessitent des modifications pour prendre en compte l'aspect continu des données et l'aspect temps réel. Les travaux réalisés dans cette thèse portent principalement sur trois contributions : (i) une étude comparative des propriétés temporelles entre une collecte périodique des données avec une base de données classique et une approche de traitement des requêtes avec une BDCSF, (ii) la proposition d’un modèle de traitement des requêtes temps réel, (iii) la mise en œuvre d’une BDCSF temps réel, basée sur les techniques décrites dans la deuxième contribution
In this thesis, we are interested in adding real-time constraints in the Wireless Sensor Networks Database (WSNDB). Temporal consistency in WSNDB must be ensured by respecting the transaction deadlines and data temporal validity, so that sensor data reflect the current state of the environment. However, delays of transmission and/or reception in a data collection process can lead to not respect the data temporal validity. A database solution is most appropriate, which should coincide with the traditional database aspects with sensors and their environment. For this purpose, the sensor in WSN is considered as a table in a distributed database, which applied transactions (queries, updates, etc.). Transactions in a WSNDB require modifications to take into account of the continuous datastream and real-time aspects. Our contribution in this thesis focus on three parts: (i) a comparative study of temporal properties between a periodic data collection based on a remote database and query processing approach with WSNDB, (ii) the proposition of a real-time query processing model, (iii) the implementation of a real time WSNDB, based on the techniques described in the second contribution

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38

"Proteolytic systems modulating collecting duct sodium transport." Tulane University, 2010.

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Serine proteases such as furin and prostasin have been shown to activate epithelial sodium channels (ENaC) in the collecting duct. Inhibition of apical proteases with aprotinin decreases Na+ current (Ieq), and subsequent application of the protease trypsin increases Ieq. However, transepithelial resistance (Rte) in M-1 mouse cortical collecting duct cells also decreases with aprotinin and increases with trypsin; Rte effects are opposite to those expected with inhibition and activation respectively of ENaC. The purpose of present studies was to characterize the regulation of Na+ transport and transepithelial permeability by proteolytic systems in the cortical collecting duct, the site of final regulation of Na+ excretion by the kidney Prostasin knockdown M-1 cells had no significant decrease in baseline Ieq and Rte. However, prostasin or trypsin significantly increased Rte in prostasin knockdown cells. These results suggest that prostasin is essential for resistance, but may be not critical for Na + current. Apical addition of ENaC inhibitory peptides LPHPLQRL (alpha-8) or PRFLNLIPLLVFNEN (gamma-15) abruptly inhibited Ieq. In contrast to trypsin and aprotinin, alpha-8 or gamma-15 had little or no effect on Rte. Apical addition of aprotinin after application of alpha-8 or gamma-15 inhibited Rte just as in cells untreated with inhibitory peptides. To elucidate if effects on Rte require Na+ transport, M-1 cells were treated with basolateral ouabain or apical amiloride (in the latter case after aprotinin pretreatment). Subsequent addition of trypsin increased Rte in both cases even in absence of transport. Basolateral application of TGF-beta1 significantly decreased Ieq. TGF-beta1 also increased paracellular permeability (indicated by the decrease in Rte), a response that is not expected based on an effect solely on ENaC. The lack of response to trypsin in TGF-beta1 treated cells implies that the downregulation of prostasin is not a major factor in the inhibition of Ieq by TGF-beta1 In conclusion, these studies indicate that proteolytic enzymes including endogenous prostasin alter Na+ transport in collecting duct cells both via the release of ENaC inhibitory peptides and in addition via the effects on Rte, probably reflecting paracellular permeability, independent of the effects on Na+ channels and Na+ transport
acase@tulane.edu

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Yi-Chun, Tsai. "Efficient Electronic Toll Collection Protocol for Intelligent Transport System." 2006. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0002-2806200618044500.

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Tsai, Yi-Chun, and 蔡宜君. "Efficient Electronic Toll Collection Protocol for Intelligent Transport System." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/10458206275702108519.

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碩士
淡江大學
資訊工程學系碩士班
94
Thanks to the rapid development recently in intelligent transport systems (ITS), especially in electronic toll collection (ETC), it has become easier for people to do electronic non-stop transactions at the lanes. This paper proposes an efficient electronic toll collection protocol for intelligent transport system. The proposed protocol, based on one-way hash functions and smart cards, provides mutual authentication when the user enters and exits the superhighway for toll collection. Each station in the protocol can handle many users at one time. The protocol works without the help of GPS. The proposed protocol is more efficient than any others.

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41

"Decentralized Control of Collective Transport by Multi-Robot Systems with Minimal Information." Doctoral diss., 2020. http://hdl.handle.net/2286/R.I.63024.

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abstract: One potential application of multi-robot systems is collective transport, a task in which multiple mobile robots collaboratively transport a payload that is too large or heavy to be carried by a single robot. Numerous control schemes have been proposed for collective transport in environments where robots can localize themselves (e.g., using GPS) and communicate with one another, have information about the payload's geometric and dynamical properties, and follow predefined robot and/or payload trajectories. However, these approaches cannot be applied in uncertain environments where robots do not have reliable communication and GPS and lack information about the payload. These conditions characterize a variety of applications, including construction, mining, assembly in space and underwater, search-and-rescue, and disaster response. Toward this end, this thesis presents decentralized control strategies for collective transport by robots that regulate their actions using only their local sensor measurements and minimal prior information. These strategies can be implemented on robots that have limited or absent localization capabilities, do not explicitly exchange information, and are not assigned predefined trajectories. The controllers are developed for collective transport over planar surfaces, but can be extended to three-dimensional environments. This thesis addresses the above problem for two control objectives. First, decentralized controllers are proposed for velocity control of collective transport, in which the robots must transport a payload at a constant velocity through an unbounded domain that may contain strictly convex obstacles. The robots are provided only with the target transport velocity, and they do not have global localization or prior information about any obstacles in the environment. Second, decentralized controllers are proposed for position control of collective transport, in which the robots must transport a payload to a target position through a bounded or unbounded domain that may contain convex obstacles. The robots are subject to the same constraints as in the velocity control scenario, except that they are assumed to have global localization. Theoretical guarantees for successful execution of the task are derived using techniques from nonlinear control theory, and it is shown through simulations and physical robot experiments that the transport objectives are achieved with the proposed controllers.
Dissertation/Thesis
Doctoral Dissertation Mechanical Engineering 2020

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"Multi-Agent Coordination and Control under Information Asymmetry with Applications to Collective Load Transport." Master's thesis, 2018. http://hdl.handle.net/2286/R.I.51713.

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abstract: Coordination and control of Intelligent Agents as a team is considered in this thesis. Intelligent agents learn from experiences, and in times of uncertainty use the knowl- edge acquired to make decisions and accomplish their individual or team objectives. Agent objectives are defined using cost functions designed uniquely for the collective task being performed. Individual agent costs are coupled in such a way that group ob- jective is attained while minimizing individual costs. Information Asymmetry refers to situations where interacting agents have no knowledge or partial knowledge of cost functions of other agents. By virtue of their intelligence, i.e., by learning from past experiences agents learn cost functions of other agents, predict their responses and act adaptively to accomplish the team’s goal. Algorithms that agents use for learning others’ cost functions are called Learn- ing Algorithms, and algorithms agents use for computing actuation (control) which drives them towards their goal and minimize their cost functions are called Control Algorithms. Typically knowledge acquired using learning algorithms is used in con- trol algorithms for computing control signals. Learning and control algorithms are designed in such a way that the multi-agent system as a whole remains stable during learning and later at an equilibrium. An equilibrium is defined as the event/point where cost functions of all agents are optimized simultaneously. Cost functions are designed so that the equilibrium coincides with the goal state multi-agent system as a whole is trying to reach. In collective load transport, two or more agents (robots) carry a load from point A to point B in space. Robots could have different control preferences, for example, different actuation abilities, however, are still required to coordinate and perform load transport. Control preferences for each robot are characterized using a scalar parameter θ i unique to the robot being considered and unknown to other robots. With the aid of state and control input observations, agents learn control preferences of other agents, optimize individual costs and drive the multi-agent system to a goal state. Two learning and Control algorithms are presented. In the first algorithm(LCA- 1), an existing work, each agent optimizes a cost function similar to 1-step receding horizon optimal control problem for control. LCA-1 uses recursive least squares as the learning algorithm and guarantees complete learning in two time steps. LCA-1 is experimentally verified as part of this thesis. A novel learning and control algorithm (LCA-2) is proposed and verified in sim- ulations and on hardware. In LCA-2, each agent solves an infinite horizon linear quadratic regulator (LQR) problem for computing control. LCA-2 uses a learning al- gorithm similar to line search methods, and guarantees learning convergence to true values asymptotically. Simulations and hardware implementation show that the LCA-2 is stable for a variety of systems. Load transport is demonstrated using both the algorithms. Ex- periments running algorithm LCA-2 are able to resist disturbances and balance the assumed load better compared to LCA-1.
Dissertation/Thesis
Masters Thesis Electrical Engineering 2018

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"Scalable Control Strategies and a Customizable Swarm Robotic Platform for Boundary Coverage and Collective Transport Tasks." Doctoral diss., 2017. http://hdl.handle.net/2286/R.I.44017.

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abstract: Swarms of low-cost, autonomous robots can potentially be used to collectively perform tasks over large domains and long time scales. The design of decentralized, scalable swarm control strategies will enable the development of robotic systems that can execute such tasks with a high degree of parallelism and redundancy, enabling effective operation even in the presence of unknown environmental factors and individual robot failures. Social insect colonies provide a rich source of inspiration for these types of control approaches, since they can perform complex collective tasks under a range of conditions. To validate swarm robotic control strategies, experimental testbeds with large numbers of robots are required; however, existing low-cost robots are specialized and can lack the necessary sensing, navigation, control, and manipulation capabilities. To address these challenges, this thesis presents a formal approach to designing biologically-inspired swarm control strategies for spatially-confined coverage and payload transport tasks, as well as a novel low-cost, customizable robotic platform for testing swarm control approaches. Stochastic control strategies are developed that provably allocate a swarm of robots around the boundaries of multiple regions of interest or payloads to be transported. These strategies account for spatially-dependent effects on the robots' physical distribution and are largely robust to environmental variations. In addition, a control approach based on reinforcement learning is presented for collective payload towing that accommodates robots with heterogeneous maximum speeds. For both types of collective transport tasks, rigorous approaches are developed to identify and translate observed group retrieval behaviors in Novomessor cockerelli ants to swarm robotic control strategies. These strategies can replicate features of ant transport and inherit its properties of robustness to different environments and to varying team compositions. The approaches incorporate dynamical models of the swarm that are amenable to analysis and control techniques, and therefore provide theoretical guarantees on the system's performance. Implementation of these strategies on robotic swarms offers a way for biologists to test hypotheses about the individual-level mechanisms that drive collective behaviors. Finally, this thesis describes Pheeno, a new swarm robotic platform with a three degree-of-freedom manipulator arm, and describes its use in validating a variety of swarm control strategies.
Dissertation/Thesis
Doctoral Dissertation Mechanical Engineering 2017

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Zaidane, Tarik. "Évaluation du comportement du système de transport flexible DAS (Demand Adaptative System)." Mémoire, 2012. http://www.archipel.uqam.ca/5108/1/M12639.pdf.

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Aujourd'hui, l'étalement des villes engendre de nouvelles conditions de déplacements qui à leur tour induisent de nouveaux rythmes urbains. Ceux-ci fragmentent l'habituel flot synchronisé des heures de pointe et imposent aux transports collectifs une perpétuelle adaptation. Notre projet vise à apporter des solutions innovantes en termes de mobilité urbaine et d'intégration d'un nouveau mode de transport flexible appelé DAS (Demand-Adaptative System, système de la demande adaptative). L'originalité de notre projet réside dans le fait que rares sont les études qui traitent ce nouveau système de transport et nous pensons que sa prise en compte peut contribuer à améliorer significativement les services de transport actuels. L'objectif de ce mémoire est donc d'évaluer le comportement du fonctionnement du système DAS sur le plan opérationnel dans la région de la rive sud de Montréal, et ce, en présence de multiples changements (internes ou externes). Dans ce projet, l'évaluation du système DAS suit le schéma présenté par Crainic et al, (2009). Il s'agit de définir des scénarios, concevoir des lignes de transport, simuler les lignes DAS, et enfin collecter les résultats et mesurer la performance du système. Nous avons commencé par l'analyse de la mobilité géographique de la région étudiée grâce aux données de l'enquête origine-destination (2003) effectuée par le réseau de transport de Longueuil (RTL). Ces données sont ensuite explorées en utilisant le logiciel ArcMap et transformées en cartes géographiques permettant ainsi de concevoir les trois lignes de transport à simuler. Après la conception de ces lignes, les matrices de la demande et de la distance propre à chaque ligne ont été identifiées. L'étape de la simulation consiste à simuler les données de ces matrices en variant plusieurs paramètres (propres et généraux), selon trois scénarios différents, et ce, en utilisant le code établit par Crainic et al. (2005), avec le langage C++, sous le système d'exploitation LINUX. Étant donné qu'un problème technique (le code établi par Crainic et al. (2005), n'a pas pris en considération quelques critères qui sont très importants pour la simulation du système DAS au niveau de la région de la rive sud de Montréal) est survenu, il fut donc impossible de simuler les matrices de la demande et distance. Nous avons donc formulé des hypothèses sur les résultats attendus en nous basant sur certains indicateurs de performance tels que la distance parcourue, la latence, le temps final d'arrivée, etc. D'après le scénario 1, nous nous attendons à ce que la distance parcourue soit acceptable et ne représente pas un obstacle pour les usagers du service DAS alors que pour le scénario 2, nous nous attendons à ce que le système DAS intègre plus d'arrêts optionnels et réagisse bien face à l'augmentation de la demande de 25%. En ce qui concerne le scénario 3, nous pensons que la ligne est plus courte ainsi que la distance parcourue. Les arrêts optionnels ne seront pas donc tous intégrés dans le trajet, ce qui va certainement limiter le nombre des usagers dans le véhicule. D'après ces hypothèses, nous pensons qu'avec le scénario 1, le système DAS fonctionne avec une efficacité et efficience opérationnelle supérieure en comparaison avec les scénarios 2 et 3. La prise en compte de ces hypothèses permet de penser à des perspectives pour des recherches futures. ______________________________________________________________________________ MOTS-CLÉS DE L’AUTEUR : Transport, Système DAS, schéma d'évaluation (Crainic et al, 2009), code de simulation (Crainic. Teodor. et al, 2005), enquête origine-destination (2003)

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"Experimental study of 2D hole systems : coherent transport in quantum dots and magnetothermopower." Université catholique de Louvain, 2007. http://edoc.bib.ucl.ac.be:81/ETD-db/collection/available/BelnUcetd-11282007-103425/.

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"Development and Analysis of Stochastic Boundary Coverage Strategies for Multi-Robot Systems." Doctoral diss., 2016. http://hdl.handle.net/2286/R.I.38559.

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abstract: Robotic technology is advancing to the point where it will soon be feasible to deploy massive populations, or swarms, of low-cost autonomous robots to collectively perform tasks over large domains and time scales. Many of these tasks will require the robots to allocate themselves around the boundaries of regions or features of interest and achieve target objectives that derive from their resulting spatial configurations, such as forming a connected communication network or acquiring sensor data around the entire boundary. We refer to this spatial allocation problem as boundary coverage. Possible swarm tasks that will involve boundary coverage include cooperative load manipulation for applications in construction, manufacturing, and disaster response. In this work, I address the challenges of controlling a swarm of resource-constrained robots to achieve boundary coverage, which I refer to as the problem of stochastic boundary coverage. I first examined an instance of this behavior in the biological phenomenon of group food retrieval by desert ants, and developed a hybrid dynamical system model of this process from experimental data. Subsequently, with the aid of collaborators, I used a continuum abstraction of swarm population dynamics, adapted from a modeling framework used in chemical kinetics, to derive stochastic robot control policies that drive a swarm to target steady-state allocations around multiple boundaries in a way that is robust to environmental variations. Next, I determined the statistical properties of the random graph that is formed by a group of robots, each with the same capabilities, that have attached to a boundary at random locations. I also computed the probability density functions (pdfs) of the robot positions and inter-robot distances for this case. I then extended this analysis to cases in which the robots have heterogeneous communication/sensing radii and attach to a boundary according to non-uniform, non-identical pdfs. I proved that these more general coverage strategies generate random graphs whose probability of connectivity is Sharp-P Hard to compute. Finally, I investigated possible approaches to validating our boundary coverage strategies in multi-robot simulations with realistic Wi-fi communication.
Dissertation/Thesis
Doctoral Dissertation Computer Science 2016

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47

Aragão, Nagayamma Kaymir Tavares de Sousa. "Maxibombos e Candongueiros em Luanda: contributo para a configuração de uma rede de transportes colectivos com recurso a tecnologias de informação geográfica." Master's thesis, 2014. http://hdl.handle.net/10437/5826.

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Orientação: Zoran Roca
As redes de transportes sempre estruturaram o território, determinando a forma como as actividades se distribuem, a população se desloca, os recursos são explorados e a administração se organiza. O crescimento da população a residir em áreas urbanas tem vindo a traduzir-se num aumento das deslocações em modos de transporte motorizados e na sua amplitude geográfica. Este fenómeno, num país como Angola, sobrevivente a uma guerra civil de 40 anos, apresenta contornos particulares na província de Luanda. Os transportes colectivos são apontados como uma parte da solução para a melhoria da mobilidade das populações e para uma maior sustentabilidade e competitividade dos territórios e das cidades, pelo que urge desenvolver um sistema que promova a intermodalidade e/ou co-modalidade na província, em detrimento do transporte individual. Este trabalho pretende constituir uma reflexão sobre estas problemáticas, tendo como objectivo último a contribuição para a definição de uma configuração de rede de transportes colectivos na província de Luanda Na abordagem prosseguida são aplicadas tecnologias de informação geográfica, com destaque para a análise de redes, a qual só foi possível porque foi suportada num trabalho de campo que abrangeu 1350 indivíduos e 345 «empresas», estas últimas sobretudo envolvidas num sector nascido da informalidade, que localmente se designa por «candongueiros». São eles que mais eficazmente garantem as necessidades de deslocação de uma população urbana em crescimento.
Transport networks always structured the territory, determining how activities are distributed, population moves, resources are exploited and the administration is organized. The growth of population living in urban areas has lead to an increase in displace-ment and its geographical range using motorized modes of transport. This phenomenon, in a country like Angola, surviving a 40 years civil war, presents particular contours in the prov-ince of Luanda. Public transportation is seen as part of the solution for improving mobility of the population and greater sustainability and competitiveness of territories and cities, so it is ur-gent to develop a system that promotes intermodality and/or co-modality in the province, in detriment of individual transport. This work is intended as a reflection on these issues, with the ultimate aim of contributing to the definition of a configuration of public transport net-work in the province of Luanda. In the pursued approach, geographic information technologies were applied, espe-cially network analysis, which was only made possible because of a field work that included 1350 individuals and 345 «firms», the latter mainly born within the informal sector, so they are locally known as «candongueiros». They ensure the displacement needs of a growing ur-ban population more effectively.

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HOUZIMOVÁ, Jana. "Analýza činnosti dopravního operátora." Master's thesis, 2008. http://www.nusl.cz/ntk/nusl-48211.

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An analysis of a transport operator´s job description My degree work is centred on the problems of a transport operator´s job in a forwarding agency. The introduction provides an explanation of a term of "dispatch service" and explains why logistics is so important in transport. Then there is a description of the transport development after 1990 and the changes transport had to undergo in the time of globalization. The main part of the work deals with the operator´s working procedure from an offer to a demand, an order and other actions to the final realization. A model example is given to represent an actual transporting process. The work also states conditions under which transport is executed, for example payment terms and terms of delivery. Next chapters outline the way of calculation, give a detailed description of collecting service (which is implemented within the bounds of CS Expres system) and of storing problems including the introduction of bar codes in stores and possibilities of logistic service extension. The conclusion is focused on the firm developing strategy.

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Silva, Ricardo Morgado. "Desenvolvimento de aplicações de Sistemas de Informação Geográfica WEB para gestão de resíduos urbanos." Master's thesis, 2015. http://hdl.handle.net/10362/15277.

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A gestão do território contribui para o desenvolvimento socioeconómico e para o alcance de necessidades coletivas. A gestão de recursos, por sua vez, é uma das vias para atingir tais propósitos, convocando agentes, entidades e serviços para a administração de um território. O crescimento social e económico e a expansão urbana das últimas décadas tiveram um impacto significativo no consumo de recursos e na decorrente produção de resíduos, fazendo da gestão dos mesmos um importante meio para a gestão de recursos, com contributo para a gestão do território. Neste contexto, surgem serviços de gestão de resíduos urbanos, que dependem de informação geográfica referente ao seu sistema e ao do ambiente territorial em que o mesmo se insere. Face ao dinamismo e às relações entre diversos fenómenos e elementos presentes no referido ambiente, o processo de gestão de resíduos urbanos torna-se um desafio cada vez mais exigente e heterogéneo, em matéria de decisão espacial. Por esse motivo, é indispensável possuir ferramentas que integrem vários dados e que possibilitem abordagens metodológicas orientadas para uma intervenção territorial mais realista. Para tal, existem diversos métodos e técnicas, assentes em Tecnologias de Informação e Comunicação, com uma considerável adesão a soluções de Sistemas de Informação Geográfica, dada a necessidade de manipular informação com carácter espacial referente à gestão de resíduos urbanos. No quadro atual da produção e da prestação de serviços através de rede digital, as plataformas Web desses Sistemas de Informação Geográfica constituem-se como um instrumento para gestão de resíduos. Considerando o exemplo do Gabinete de Estudos, Planeamento e Controlo, dos Serviços Intermunicipalizados de Águas e Resíduos dos Municípios de Loures e Odivelas, no presente Trabalho de Projeto, pretende-se avaliar a situação atual das metodologias e dos recursos tecnológicos que um serviço deste tipo possui, percebendo o contributo que aplicações de Sistemas de Informação Geográfica Web podem ter para a concretização da sua missão, na conjuntura atual da tecnologia, da informação e da comunicação na Administração Pública. Assim, o presente Trabalho de Projeto propõe também um modelo de desenvolvimento das referidas aplicações, assentes em Sistemas de Informação Geográfica Desktop e Web de código aberto, livres e gratuitos. As aplicações abarcam informação interna, referente ao sistema de resíduos urbanos, dos Serviços Intermunicipalizados de Águas e Resíduos dos Municípios de Loures e Odivelas, e informação externa diversa, referente ao seu território de intervenção. A integração e relação da informação interna e externa, com resultados nas aplicações, são apresentadas como possíveis meios de assistência aos procedimentos efetuados no Gabinete de Estudos, Planeamento e Controlo e à prestação efetiva do serviço de gestão de resíduos urbanos. Igualmente, é possível inferir a versatilidade, a aplicabilidade e o potencial de aplicações de Sistemas de Informação Geográfica, em diversas vertentes e escalas de gestão do território.

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Dissertations / Theses on the topic 'Collective transport system'

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