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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
131

CONTRAM : middleware voltado a interoperabilidade entre sistemas de gerenciamento de tráfego urbano e redes de controladores semafóricos sob os paradigmas de sistemas de transportes inteligentes

Morais, Lincoln Luiz de January 2001 (has links)
Sistemas que utilizam tecnologias computacionais no tratamento de problemas relativos ao trânsito são classificados como ITS ou Intelligent Transportation System [FAR 97]. Esses sistemas buscam, através de sincronismo e eficiência no controle de sinais de tráfego, gerenciar o fluxo de veículos na malha viária minimizando o problema de congestionamento urbano e, consequentemente, problemas decorrentes desse congestionamento como um maior consumo de combustível, maior tempo de espera para veículos específicos como ambulâncias, bombeiros, polícia e transporte coletivo, e maiores índices de poluição ambiental, sonora e atmosférica, entre outros [FED 99A]. Atuando na coleta dos dados a serem tratados e processados por um Sistema de Gerenciamento de Tráfego Urbano ou SGTU, estão os dispositivos de controle de tráfego, como semáforos e sensores para detectar e quantificar o volume de veículos e seus respectivos controladores. Computacionalmente, são fatores relevantes a interoperabilidade entre esses dispositivos de controle e padronizações adotadas, de forma que um SGTU possa evoluir através da agregação de novas facilidades e recursos ou ainda desabilitar ou modificar os já existentes. Dada as características da administração pública e dos procedimentos de aquisição, são adquiridos controladores de diferentes fabricantes e modelos, dificultando a integração entre os mesmos em função de suas tecnologias proprietárias e da falta de uma política e esforço governamental em busca de padronizações para o setor, principalmente no que diz respeito à interoperabilidade. Recentemente iniciou-se uma mobilização para se estabelecer padrões voltados à área de transporte nos Estados Unidos [EUL 95], Japão [JAP 99] e Europa [KAR 99], através da participação dos órgãos que administram o tráfego urbano, dos fabricantes de sistemas de hardware e software, da comunidade acadêmica, dos órgãos de padronizações locais e das variadas instâncias da esfera governamental. Este trabalho apresenta o CONTRAM, modelo de um middleware que, tratando os controladores de dispositivos de controle tráfego instalados ao longo da malha viária baseado nos paradigmas de sistemas distribuídos, possa ser utilizado como interface entre estes e as aplicações computacionais de gerenciamento de tráfego, permitindo a integração de diferentes especificações em um único sistema. O seu escopo é atender às transações de consulta e configuração de valores dos dados utilizados para controlar, monitorar e gerenciar o tráfego de veículos, liberando um SGTU de conhecer detalhes técnicos envolvidos na comunicação com os controladores. O modelo baseia-se em uma arquitetura multicamadas, 4-tier, permitindo o gerenciamento de recursos de forma centralizada ou distribuída, neste último trocando dados através da internet, e integra-se aos sistemas legados e OO através do método black-box e chamada de objetos respectivamente. Foi projetado tendo em mente a utilização de padrões abertos da indústria da Informática e de Transportes, a interoperabilidade entre diferentes elementos tecnológicos voltados ao controle de tráfego e a expansibilidade segura de um SGTU. Para alcançar seu objetivo, faz uso de tecnologias baseadas em metadados e agentes SNMP. / Systems that use computational technologies in the handling of the traffic problems are classified as ITS or Intelligent Transportation System. These systems search through synchronism and efficiency in traffic signs control, to manage the stream of vehicles in the road network, minimizing the problem of urban congestion and, consequently, decurrent problems of this congestion as a major fuel consumption, major waiting time for specific vehicles as ambulances, firemen, policy and collective carrier and greaters indices of ambient pollution, sonorous and atmospheric, amongst others. Acting in the data collection to be treat and processed for a Urban Traffic Control System or UTCS, they are the traffic control devices, as traffic lights and sensors to detect and quantify the volume of vehicles and, its respective controllers. Computational, important factors are the interoperability among these control devices and standardizations adopted, allowing UTCS customize through the new easinesses and features aggregation or still disable or modify already the existing ones. Given the features of the public management and the acquisition procedures, different controllers models of different manufacturers are acquired, making it difficult the integration in function of its proprietary technologies and the lack of one politics and governmental effort in considering standardizations for the sector, mainly about interoperability. Recently was initiated a mobilization of standards establishing to the Transportation area in the United States, Japan and Europe, through the participation of the agencies that manage the urban traffic, hardware and software solutions providers, academic community, local standardizations agencies and the varied instances of the governmental sphere. This work presents the CONTRAM, a middleware model that, treating the traffic controllers installed in road networks based in distributed systems paradigms, can be used as interface between the computational applications of traffic management and the controllers of control devices, allowing the integration of different specifications in an only system. Its target is to take care of to get and set transactions on data values used to control, monitor and manage the vehicles traffic, liberating a UTCS to know technician details in the communication with the controllers. The model is based on multilayers architecture, 4-tier, allowing the resources management in centered or distributed form, in last one changing data through the Internet and it is combined to the legacies systems and OO through the black-box and object call method respectively. It was projected having in mind the use of open standards of the Transportation and Computer science industries , interoperability between different traffic control technological elements and the UTCS expansibility safe. To reach its objective, it makes use of metadata and SNMP agents technologies.
132

Policy-driven Security Management for Gateway-Oriented Reconfigurable Ecosystems

January 2015 (has links)
abstract: With the increasing user demand for low latency, elastic provisioning of computing resources coupled with ubiquitous and on-demand access to real-time data, cloud computing has emerged as a popular computing paradigm to meet growing user demands. However, with the introduction and rising use of wear- able technology and evolving uses of smart-phones, the concept of Internet of Things (IoT) has become a prevailing notion in the currently growing technology industry. Cisco Inc. has projected a data creation of approximately 403 Zetabytes (ZB) by 2018. The combination of bringing benign devices and connecting them to the web has resulted in exploding service and data aggregation requirements, thus requiring a new and innovative computing platform. This platform should have the capability to provide robust real-time data analytics and resource provisioning to clients, such as IoT users, on-demand. Such a computation model would need to function at the edge-of-the-network, forming a bridge between the large cloud data centers and the distributed connected devices. This research expands on the notion of bringing computational power to the edge- of-the-network, and then integrating it with the cloud computing paradigm whilst providing services to diverse IoT-based applications. This expansion is achieved through the establishment of a new computing model that serves as a platform for IoT-based devices to communicate with services in real-time. We name this paradigm as Gateway-Oriented Reconfigurable Ecosystem (GORE) computing. Finally, this thesis proposes and discusses the development of a policy management framework for accommodating our proposed computational paradigm. The policy framework is designed to serve both the hosted applications and the GORE paradigm by enabling them to function more efficiently. The goal of the framework is to ensure uninterrupted communication and service delivery between users and their applications. / Dissertation/Thesis / Masters Thesis Computer Science 2015
133

Estimation du risque aux intersections pour applications sécuritaires avec véhicules communicants / Risk estimation at road intersections for connected vehicle safety applications

Lefèvre, Stéphanie 22 October 2012 (has links)
Les intersections sont les zones les plus dangereuses du réseau routier. Les statistiques montrent que la plupart des accidents aux intersections sont causés par des erreurs des conducteurs, et que la plupart pourraient être évités à l'aide de systèmes d'aide à la conduite. En particulier, les communications inter-véhiculaires ouvrent de nouvelles opportunités pour les applications sécuritaires aux intersections. Le partage d'informations entre les véhicules via des liens sans fil permet aux véhicules de percevoir leur environnement au-delà des limites du champ de vision des capteurs embarqués. Grâce à cette représentation élargie de l'environnement dans l'espace et dans le temps, la compréhension de situation est améliorée et les situations dangereuses peuvent être détectées plus tôt. Cette thèse aborde le problème de l'estimation du risque aux intersections d'un nouveau point de vue : une structure de raisonnement est proposée pour analyser les situations routières et le risque de collision à un niveau sémantique plutôt qu'au niveau des trajectoires. Le risque est déterminé en estimant les intentions des conducteurs et en identifiant les potentiels conflits, sans avoir à prédire les futures trajectoires des véhicules. L'approche proposée a été validée par des expérimentations en environnement réel à l'aide de véhicules équipés de modems de communication véhicule-véhicule, ainsi qu'en simulation. Les résultats montrent que l'algorithme permet de détecter les situations dangereuses à l'avance et qu'il respecte les contraintes temps-réel des applications sécuritaires. Il y a deux différences principales entre l'approche proposée et les travaux existants. Premièrement, l'étape de prédiction de trajectoire est évitée. Les situations dangereuses sont identifiées en comparant ce que les conducteurs ont l'intention de faire avec ce qui est attendu d'eux d'après les règles de la circulation et le contexte. Le raisonnement sur les intentions et les attentes est réalisé de manière probabiliste afin de prendre en compte les incertitudes des mesures capteur et les ambiguïtés sur l'interprétation. Deuxièmement, le modèle proposé prend en compte les informations sur le contexte situationnel, c'est-à-dire que l'influence de la géométrie de l'intersection et des actions des autres véhicules est prise en compte lors de l'analyse du comportement d'un véhicule. / Intersections are the most complex and dangerous areas of the road network. Statistics show that most road intersection accidents are caused by driver error and that many of them could be avoided through the use of Advanced Driver Assistance Systems. In particular, vehicular communications open new opportunities for safety applications at road intersections. The sharing of information between vehicles over wireless links allows vehicles to perceive their environment beyond the field-of-view of their on-board sensors. Thanks to this enlarged representation of the environment in time and space, situation assessment is improved and dangerous situations can be detected earlier. This thesis tackles the problem of risk estimation at road intersections from a new perspective: a framework is proposed for reasoning about traffic situations and collision risk at a semantic level instead of at a trajectory level. Risk is assessed by estimating the intentions of drivers and looking for conflicts in them, rather than by predicting the future trajectories of the vehicles and looking for intersections between them. The proposed approach was validated in field trials using passenger vehicles equipped with vehicle-to-vehicle wireless communication modems, and in simulation. The results demonstrate that this algorithm allows the early detection of dangerous situations in a reliable manner and complies with real-time constraints. The proposed approach differs from previous works in two key aspects. Firstly, it does not rely on trajectory prediction to assess the risk of a situation. Dangerous situations are identified by comparing what drivers intend to do with what they are expected to do according to the traffic rules and the current context. The reasoning about intentions and expectations is performed in a probabilistic manner to take into account sensor uncertainties and interpretation ambiguities. Secondly, the proposed motion model includes information about the situational context. Both the layout of the intersection and the actions of other vehicles are taken into account as factors influencing the behavior of a vehicle.
134

CONTRAM : middleware voltado a interoperabilidade entre sistemas de gerenciamento de tráfego urbano e redes de controladores semafóricos sob os paradigmas de sistemas de transportes inteligentes

Morais, Lincoln Luiz de January 2001 (has links)
Sistemas que utilizam tecnologias computacionais no tratamento de problemas relativos ao trânsito são classificados como ITS ou Intelligent Transportation System [FAR 97]. Esses sistemas buscam, através de sincronismo e eficiência no controle de sinais de tráfego, gerenciar o fluxo de veículos na malha viária minimizando o problema de congestionamento urbano e, consequentemente, problemas decorrentes desse congestionamento como um maior consumo de combustível, maior tempo de espera para veículos específicos como ambulâncias, bombeiros, polícia e transporte coletivo, e maiores índices de poluição ambiental, sonora e atmosférica, entre outros [FED 99A]. Atuando na coleta dos dados a serem tratados e processados por um Sistema de Gerenciamento de Tráfego Urbano ou SGTU, estão os dispositivos de controle de tráfego, como semáforos e sensores para detectar e quantificar o volume de veículos e seus respectivos controladores. Computacionalmente, são fatores relevantes a interoperabilidade entre esses dispositivos de controle e padronizações adotadas, de forma que um SGTU possa evoluir através da agregação de novas facilidades e recursos ou ainda desabilitar ou modificar os já existentes. Dada as características da administração pública e dos procedimentos de aquisição, são adquiridos controladores de diferentes fabricantes e modelos, dificultando a integração entre os mesmos em função de suas tecnologias proprietárias e da falta de uma política e esforço governamental em busca de padronizações para o setor, principalmente no que diz respeito à interoperabilidade. Recentemente iniciou-se uma mobilização para se estabelecer padrões voltados à área de transporte nos Estados Unidos [EUL 95], Japão [JAP 99] e Europa [KAR 99], através da participação dos órgãos que administram o tráfego urbano, dos fabricantes de sistemas de hardware e software, da comunidade acadêmica, dos órgãos de padronizações locais e das variadas instâncias da esfera governamental. Este trabalho apresenta o CONTRAM, modelo de um middleware que, tratando os controladores de dispositivos de controle tráfego instalados ao longo da malha viária baseado nos paradigmas de sistemas distribuídos, possa ser utilizado como interface entre estes e as aplicações computacionais de gerenciamento de tráfego, permitindo a integração de diferentes especificações em um único sistema. O seu escopo é atender às transações de consulta e configuração de valores dos dados utilizados para controlar, monitorar e gerenciar o tráfego de veículos, liberando um SGTU de conhecer detalhes técnicos envolvidos na comunicação com os controladores. O modelo baseia-se em uma arquitetura multicamadas, 4-tier, permitindo o gerenciamento de recursos de forma centralizada ou distribuída, neste último trocando dados através da internet, e integra-se aos sistemas legados e OO através do método black-box e chamada de objetos respectivamente. Foi projetado tendo em mente a utilização de padrões abertos da indústria da Informática e de Transportes, a interoperabilidade entre diferentes elementos tecnológicos voltados ao controle de tráfego e a expansibilidade segura de um SGTU. Para alcançar seu objetivo, faz uso de tecnologias baseadas em metadados e agentes SNMP. / Systems that use computational technologies in the handling of the traffic problems are classified as ITS or Intelligent Transportation System. These systems search through synchronism and efficiency in traffic signs control, to manage the stream of vehicles in the road network, minimizing the problem of urban congestion and, consequently, decurrent problems of this congestion as a major fuel consumption, major waiting time for specific vehicles as ambulances, firemen, policy and collective carrier and greaters indices of ambient pollution, sonorous and atmospheric, amongst others. Acting in the data collection to be treat and processed for a Urban Traffic Control System or UTCS, they are the traffic control devices, as traffic lights and sensors to detect and quantify the volume of vehicles and, its respective controllers. Computational, important factors are the interoperability among these control devices and standardizations adopted, allowing UTCS customize through the new easinesses and features aggregation or still disable or modify already the existing ones. Given the features of the public management and the acquisition procedures, different controllers models of different manufacturers are acquired, making it difficult the integration in function of its proprietary technologies and the lack of one politics and governmental effort in considering standardizations for the sector, mainly about interoperability. Recently was initiated a mobilization of standards establishing to the Transportation area in the United States, Japan and Europe, through the participation of the agencies that manage the urban traffic, hardware and software solutions providers, academic community, local standardizations agencies and the varied instances of the governmental sphere. This work presents the CONTRAM, a middleware model that, treating the traffic controllers installed in road networks based in distributed systems paradigms, can be used as interface between the computational applications of traffic management and the controllers of control devices, allowing the integration of different specifications in an only system. Its target is to take care of to get and set transactions on data values used to control, monitor and manage the vehicles traffic, liberating a UTCS to know technician details in the communication with the controllers. The model is based on multilayers architecture, 4-tier, allowing the resources management in centered or distributed form, in last one changing data through the Internet and it is combined to the legacies systems and OO through the black-box and object call method respectively. It was projected having in mind the use of open standards of the Transportation and Computer science industries , interoperability between different traffic control technological elements and the UTCS expansibility safe. To reach its objective, it makes use of metadata and SNMP agents technologies.
135

Veículo-sensor: estado da arte e proposta de método orientativo para especificação do sistema de posicionamento veicular. / Vehicle as a sensor: state of the art and proposition of an orientative method to specify the vehicular positioning system.

Rafael Henrique de Oliveira 07 August 2017 (has links)
Plataformas móveis, como smartphones, tablets e também veículos, têm cada vez mais possibilitado a coleta e análise de dados de seu entorno. Essa oportunidade de sensoriamento de diferentes fenômenos oferece maior cobertura espaço-temporal a menor custo em relação às técnicas tradicionais. O dinamismo dessa abordagem traz desafios relacionados ao posicionamento desses sensores e ao georreferenciamento das informações coletadas. Desta forma, a presente pesquisa tem como objetivo propor método orientativo de especificação de técnicas de posicionamento no contexto do uso do veículo enquanto sensor. Inicialmente, a partir de levantamento bibliográfico, caracteriza-se a evolução do conceito de veículo-sensor e seu emprego no sensoriamento da fluidez do tráfego, das condições do pavimento, de qualidade do ar, entre outras variáveis. Descreve-se o estado da arte nesse campo de pesquisa, identificando lacunas e pontos a serem mais bem estudados. Em um segundo momento, identificando o posicionamento como tópico pouco discutido nesse contexto, o trabalho dedica-se à definição de método orientativo de especificação de sistemas de posicionamento para veículossensores, tendo em conta os requisitos associados às diferentes variáveis a serem sensoriadas. Ao fim, apresenta-se estudo de campo referente ao uso de veículos na identificação de ocorrência de lombadas, empregando as ferramentas estabelecidas nessa dissertação e pormenorizando a discussão do sistema de posicionamento. Dessa forma, o trabalho contribui para a caracterização dos sistemas de sensoriamento baseados em veículos e a identificação do posicionamento como parâmetro fundamental para a qualidade desses sistemas. / Mobile devices such as smartphones, tablets and also vehicles have increasingly enabled gathering and analysing data from its environment. This opportunity of sensing different phenomena offers greater spatiotemporal coverage at less cost when compared to the traditional techniques. The dynamics of this approach has challenges related to the positioning of this sensors and the georeferencing of sensed data. Thus, this research aims to propose an orientative method to specify the positioning system for use with vehicles working as mobile sensors. Firstly, by doing a literature review, the purpose is to characterize the evolution of the concept of vehicle as a mobile sensor and its use in sensing traffic conditions, road conditions, air quality and other variables. The state of the art in this research field is described and the gaps and open questions are identified. In a second moment, after identifying the positioning in this context as an understudied area, this research will work on discussing an orientative method to specify the positioning system considering specificities and requirements associated with the different sensored phenomena. At the end, this work describes an exploratory study using a vehicle to identify road bumps, applying the tools defined in the method and detailing the discussion about the positioning system. Therefore, this work contributes to the characterization of sensing systems based on vehicles and the identification of the vehicular positioning as a fundamental parameter for the quality of these systems.
136

CONTRAM : middleware voltado a interoperabilidade entre sistemas de gerenciamento de tráfego urbano e redes de controladores semafóricos sob os paradigmas de sistemas de transportes inteligentes

Morais, Lincoln Luiz de January 2001 (has links)
Sistemas que utilizam tecnologias computacionais no tratamento de problemas relativos ao trânsito são classificados como ITS ou Intelligent Transportation System [FAR 97]. Esses sistemas buscam, através de sincronismo e eficiência no controle de sinais de tráfego, gerenciar o fluxo de veículos na malha viária minimizando o problema de congestionamento urbano e, consequentemente, problemas decorrentes desse congestionamento como um maior consumo de combustível, maior tempo de espera para veículos específicos como ambulâncias, bombeiros, polícia e transporte coletivo, e maiores índices de poluição ambiental, sonora e atmosférica, entre outros [FED 99A]. Atuando na coleta dos dados a serem tratados e processados por um Sistema de Gerenciamento de Tráfego Urbano ou SGTU, estão os dispositivos de controle de tráfego, como semáforos e sensores para detectar e quantificar o volume de veículos e seus respectivos controladores. Computacionalmente, são fatores relevantes a interoperabilidade entre esses dispositivos de controle e padronizações adotadas, de forma que um SGTU possa evoluir através da agregação de novas facilidades e recursos ou ainda desabilitar ou modificar os já existentes. Dada as características da administração pública e dos procedimentos de aquisição, são adquiridos controladores de diferentes fabricantes e modelos, dificultando a integração entre os mesmos em função de suas tecnologias proprietárias e da falta de uma política e esforço governamental em busca de padronizações para o setor, principalmente no que diz respeito à interoperabilidade. Recentemente iniciou-se uma mobilização para se estabelecer padrões voltados à área de transporte nos Estados Unidos [EUL 95], Japão [JAP 99] e Europa [KAR 99], através da participação dos órgãos que administram o tráfego urbano, dos fabricantes de sistemas de hardware e software, da comunidade acadêmica, dos órgãos de padronizações locais e das variadas instâncias da esfera governamental. Este trabalho apresenta o CONTRAM, modelo de um middleware que, tratando os controladores de dispositivos de controle tráfego instalados ao longo da malha viária baseado nos paradigmas de sistemas distribuídos, possa ser utilizado como interface entre estes e as aplicações computacionais de gerenciamento de tráfego, permitindo a integração de diferentes especificações em um único sistema. O seu escopo é atender às transações de consulta e configuração de valores dos dados utilizados para controlar, monitorar e gerenciar o tráfego de veículos, liberando um SGTU de conhecer detalhes técnicos envolvidos na comunicação com os controladores. O modelo baseia-se em uma arquitetura multicamadas, 4-tier, permitindo o gerenciamento de recursos de forma centralizada ou distribuída, neste último trocando dados através da internet, e integra-se aos sistemas legados e OO através do método black-box e chamada de objetos respectivamente. Foi projetado tendo em mente a utilização de padrões abertos da indústria da Informática e de Transportes, a interoperabilidade entre diferentes elementos tecnológicos voltados ao controle de tráfego e a expansibilidade segura de um SGTU. Para alcançar seu objetivo, faz uso de tecnologias baseadas em metadados e agentes SNMP. / Systems that use computational technologies in the handling of the traffic problems are classified as ITS or Intelligent Transportation System. These systems search through synchronism and efficiency in traffic signs control, to manage the stream of vehicles in the road network, minimizing the problem of urban congestion and, consequently, decurrent problems of this congestion as a major fuel consumption, major waiting time for specific vehicles as ambulances, firemen, policy and collective carrier and greaters indices of ambient pollution, sonorous and atmospheric, amongst others. Acting in the data collection to be treat and processed for a Urban Traffic Control System or UTCS, they are the traffic control devices, as traffic lights and sensors to detect and quantify the volume of vehicles and, its respective controllers. Computational, important factors are the interoperability among these control devices and standardizations adopted, allowing UTCS customize through the new easinesses and features aggregation or still disable or modify already the existing ones. Given the features of the public management and the acquisition procedures, different controllers models of different manufacturers are acquired, making it difficult the integration in function of its proprietary technologies and the lack of one politics and governmental effort in considering standardizations for the sector, mainly about interoperability. Recently was initiated a mobilization of standards establishing to the Transportation area in the United States, Japan and Europe, through the participation of the agencies that manage the urban traffic, hardware and software solutions providers, academic community, local standardizations agencies and the varied instances of the governmental sphere. This work presents the CONTRAM, a middleware model that, treating the traffic controllers installed in road networks based in distributed systems paradigms, can be used as interface between the computational applications of traffic management and the controllers of control devices, allowing the integration of different specifications in an only system. Its target is to take care of to get and set transactions on data values used to control, monitor and manage the vehicles traffic, liberating a UTCS to know technician details in the communication with the controllers. The model is based on multilayers architecture, 4-tier, allowing the resources management in centered or distributed form, in last one changing data through the Internet and it is combined to the legacies systems and OO through the black-box and object call method respectively. It was projected having in mind the use of open standards of the Transportation and Computer science industries , interoperability between different traffic control technological elements and the UTCS expansibility safe. To reach its objective, it makes use of metadata and SNMP agents technologies.
137

Plate-forme de simulation pour l'aide à la décision : application à la régulation des systèmes de transport urbain / Simulation platform for decision support : application to the regulation of urban transportation systems

Nguyen, Quoc Tuan 19 February 2015 (has links)
La complexité des systèmes de transport rend difficile la maîtrise de leur conception dans la mesure où ils intègrent des composantes technologiques, mais aussi sociologiques et politiques. Il est alors opportun de proposer un système destiné à aider à la définition d’une politique de transport urbain. L’objectif principal de notre recherche est de proposer l’architecture logicielle d’un outil de simulation visant à aider un décideur, chargé de la régulation d’un système de transport urbain, pour son travail d’analyse et d’évaluation des impacts des stratégies de régulation. Notre système est basé sur un simulateur à base d’agents intégrant des informations géographiques et temporelles pour évaluer des scénarii de régulation. En termes d’architecture du système, nous avons adopté une approche «système de systèmes», principalement structurée par couches, afin de modéliser les principaux éléments du système. La validation de notre outil de simulation a pu être effectuée à partir d’une étude de cas de taille et de complexité significative puisque nous disposons des enquêtes de déplacement, de recensement, et des mesures de trafic. Nous avons réalisé un prototype pour les déplacements des usagers dans la ville de La Rochelle à partir des données statistiques de l’INSEE et de la BD TOPO 2 de l’IGN en utilisant la plate-forme de simulation GAMA. / Transport systems are becoming more complex and must incorporate not only technological components, but also sociological and political ones. In particular, they should be easy to adapt in order to incorporate the goals set by decision makers, such as the integration of sustainable development settings. The main objective of our research is to propose software architecture of a simulation tool to help a decision maker, responsible for the regulation of an urban transportation system to analyze and evaluate the impacts of regulatory strategies. We propose a system to assist in the definition of an urban transportation policy. Our system is based on an agent-based simulation integrating spatial and temporal information to evaluate regulatory scenarios. In terms of system architecture, we adopted a “system of systems” approach, mainly structured in layers, in order to model the main elements of the system. The validation of our simulation tool could be done from a case study of significant size and complexity because we have travel surveys, census, and traffic measurements. We made a prototype for the movement of people in the city of La Rochelle from statistical data of INSEE and the BD TOPO 2 of IGN using the GAMA platform.
138

An Efficient Vision-Based Pedestrian Detection and Tracking System for ITS Applications

Zuo, Tianyu January 2014 (has links)
In this thesis, a novel Pedestrian Protection System (PPS), composed of the Pedestrian Detection System (PDS) and the Pedestrian Tracking System (PTS), was proposed. The PPS is a supplementary application for the Advanced Driver Assistance System, which is used to avoid collisions between vehicles and pedestrians. The Pedestrian Detection System (PDS) is used to detect pedestrians from near to far ranges with the feature-classi er-based detection method (HOG + SVM). To achieve pedestrian detection from near to far ranges, a novel structure was proposed. The structure of our PDS consists of two cameras (called CS and CL separately). The CS is equipped with a short focal length lens to detect pedestrians in near-to-mid range; and, the CL is equipped with a long focal length lens to detect pedestrians in mid-to-far range. To accelerate the processing speed of pedestrian detection, the parallel computing capacity of GPU was utilized in the PDS. The synchronization algorithm is also introduced to synchronize the detection results of CS and CL. Based on the novel pedestrian detection structure, the detection process can reach a distance which is more than 130 meters away without decreasing detection accuracy. The detection range can be extended more than 100 meters without decreasing the processing speed of pedestrian detection. Afterwards, an algorithm to eliminate duplicate detection results is proposed to improve the detection accuracy. The Pedestrian Tracking System (PTS) is applied following the Pedestrian Detection System. The PTS is used to track the movement trajectory of pedestrians and to predict the future motion and movement direction. A C + + class (called pedestrianTracking class, which is short for PTC) was generated to operate the tracking process for every detected pedestrian. The Kalman lter is the main algorithm inside the PTC. During the operation of PPS, the nal detection results of each frame from PDS will be transmitted to the PTS to enable the tracking process. The new detection results will be used to update the existing tracking results in the PTS. Moreover, if there is a newly detected pedestrian, a new process will be generated to track the pedestrian in the PTS. Based on the tracking results in PTS, the movement trajectory of pedestrians can be obtained and their future motion and movement direction can be predicted. Two kinds of alerts are generated based on the predictions: warning alert and dangerous alert. These two alerts represent di erent situations; and, they will alert drivers to the upcoming situations. Based on the predictions and alerts, the collisions can be prevented e ectively. The safety of pedestrians can be guaranteed.
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Réseaux de capteurs sans-fil pour la cartographie à l'intérieur et la localisation précise servant la navigation à basse vitesse dans les villes intelligentes / Wireless sensor networks for indoor mapping and accurate localization for low speed navigation in smart cities

Nguyen, Dinh-Van 05 December 2018 (has links)
Avec la demande croissante d'espace urbain, de plus en plus de parkings à plusieurs étages sont nécessaires. Bien que ces parkings contribuent à une utilisation plus efficace de l'espace urbain, ils introduisent également un nouveau problème. Les rapports suggèrent environ 70 millions d'heures de recherche d'emplacements de stationnement chaque année, soit une perte équivalente de 700 millions d'euros pour la seule France. En outre, les utilisations des parkings vont au-delà de leurs objectifs initiaux. Des fonctionnalités exigeantes telles que le chargeur électrique, la réservation en ligne de places de stationnement, le guidage dynamique ou le paiement mobile, etc. transforment un parking en un environnement intelligent et compétitif. Une solution à ce problème consiste à développer un système de navigation autonome pour les véhicules intelligents en situation de parking. La thèse identifiera une de ces sous-tâches, à savoir la localisation dans des environnements non autorisés par GPS. Cette thèse présentera une nouvelle méthode pour résoudre le problème indiqué tout en maintenant le système en respectant quatre critères: disponibilité, évolutivité, universalité et précision. Il y a deux étapes principales: (1) une solution permettant de reproduire le comportement du GPS pour un environnement refusé par GPS, et (2) un cadre permettant la fusion de systèmes de type GPS avec d'autres méthodes de localisation pour obtenir une précision de localisation élevée. Tout d'abord, un système de localisation Wi-Fi Fingerprinting est utilisé. Une approche utilisant un réseau de neurones d'ensemble sur une base de données d'empreintes hybrides Wi-Fi est proposée dans cette thèse. Des expériences menées sur une durée d'un an montrent que ce système est capable de localiser des véhicules présentant une erreur moyenne de 2,25 m dans le repère global (WGS84). Deuxièmement, une solution de localisation complète doit être une fusion de plusieurs techniques. Cela permet aux niveaux de localisation global et local de fonctionner ensemble. Parallèlement, la redondance dans le système améliore la précision et la fiabilité. Dans cette thèse, un cadre de fusion flexible pour plusieurs capteurs de localisation est proposé. Ce cadre de fusion traitera non seulement de l'environnement refusé par le GPS, mais pourrait également être utilisé dans l'environnement assisté par GPS et assurer une transition en douceur entre les deux zones. Pour accomplir cette tâche exigeante, un filtre à particules modèle de mélange gaussien est développé. Alors que le modèle de mouvement de ce filtre à particules intègre des données provenant de l'IMU (unité de mesure inertielle) ou du laser-SLAM, le modèle de correction est un modèle de mélange gaussien de plusieurs observations obtenues à partir du système de localisation d'empreintes digitales Wi-Fi. Avec deux véhicules intelligents (une Cybercar et une Citroen C1), 64 expériences ont été réalisées pour valider le cadre. Une erreur de localisation moyenne de 0,5 m est obtenue dans un cadre de coordonnées global. Comparez avec d'autres solutions avec une erreur de localisation moyenne de 0,2 m dans les cadres de coordonnées locales; Cette solution proposée présente également des avantages en termes d'évolutivité, de disponibilité et d'universalité. / With the increasing demand for urban space, more and more multistory carparks are needed. Although these carparks help to utilize urban space more efficient, they also introduce a new problem. Reports suggest approximately 70 million hours of parking slot searching each year, equivalently 700 million euros loss for France alone. In addition, carparks uses are exceeding their original purposes. Demanding features such as electric charger, online booking of parking spaces, dynamic guidance or mobile payment etc. turn a carpark into a competitive smart environment. One solution to this problem is to develop an autonomous navigation system for intelligent vehicles in the carpark situation. The thesis will identify one of these sub-tasks namely localization in GPS-denied environments. This thesis will present a novel method to solve the indicated problem while keeping the system follows four criteria: availability, scalability, universality and accuracy. There are two main steps: (1) a solution to replicate the GPS behaviour for the GPS-denied environment, and (2) a framework that allows the fusion of GPS-like systems with other localization methods to achieve a high localization accuracy. First, a Wi-Fi Fingerprinting localization system is employed. An approach using an ensemble neural network on a hybrid Wi-Fi fingerprinting database is proposed in this thesis. Experiments in a year-long duration show that this system is capable of localizing vehicles with 2.25m of mean error in the global coordinate frame (WGS84). Second, a complete localization solution must be a fusion of multiple techniques. This allows global as well as local levels of localization to function together. At the same time, having redundancy in the system boosts accuracy and reliability. In this thesis, a flexible fusion framework for multiple localization sensors is proposed. This fusion framework will not only deal with the GPS-denied environment but could be potentially used in the GPS-aided environment and provide a smooth transition between the two areas. To accomplish this demanding task, a Gaussian Mixture Model Particle Filter is developed. While the motion model of this particle filter incorporates data from the IMU (Inertial Measurement Unit) or laser-SLAM, the correction model is a Gaussian mixture model of multiple observations obtained from the Wi-Fi fingerprinting localization system. With two intelligent vehicles (a Cybercar and a Citroen C1 car), 64 experiments were carried out to validate the framework. A mean localization error of 0.5m is achieved in a global coordinate frame. Compare to other solutions with 0.2m of mean localization error in local coordinate frames; this proposed solution has advantages in terms of scalability, availability and universality as well.
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Freeway Corridor Management: tools and strategies

Saad, Rani A. 26 January 2010 (has links)
Master of Science

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