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Contribuições ao estudo de implantação de pedágio urbano em São Paulo. / Contributions towards the study of congestion charging systems in São Paulo.Dias, Felipe Ferreira 01 April 2015 (has links)
A Região Metropolitana de São Paulo (RMSP) sofre de sérios problemas de congestionamento, assim como muitas outras cidades de grande porte. Uma possível solução, proposta por pesquisadores de transportes, economia e ciências ambientais, é a implantação de um sistema de congestion charging, chamada no Brasil de pedágio urbano. Um dos objetivos do presente trabalho foi estabelecer os conceitos relacionados a este assunto e ilustrar as principais questões relacionadas à sua implantação. Espera-se que este trabalho possa auxiliar o desenvolvimento de estudos de avaliação da viabilidade e de impactos de sistemas propostos de congestion charging. Para atingir este objetivo, toca-se em diversos assuntos, como a definição de congestionamento e as formas de medi-lo, a base conceitual e teórica dos sistemas de congestion charging e seus diversos esquemas de diferenciação. São expostas também as medidas de mitigação de congestionamento que já foram implantadas na RMSP, quais foram os estudos já desenvolvidos considerando este tipo de política para a RMSP, e casos em que sistemas de congestion charging já foi implantado. Neste trabalho, desenvolveu-se também um modelo de escolha discreta a partir dos dados da Pesquisa Origem e Destino 2007 do METRÔ, onde pessoas deveriam escolher entre \"Transporte Coletivo\" e \"Transporte Público\". Este modelo foi utilizado para avaliar o potencial de impacto na divisão modal e de arrecadação de um congestion charge aplicado ao centro expandido de São Paulo. Adverte-se, porém, que os resultados obtidos são meramente ilustrativos. Mostra-se, também, que é possível avaliar a capacidade ociosa do sistema de transporte coletivo a partir dos dados disponíveis de bilhetagem e de GPS dos ônibus. Este processo é exemplificado através do cálculo de capacidade de uma única viagem de um único ônibus, dada a dificuldade de automatização deste processo para abranger toda a frota. / The São Paulo Metropolitan Region (SPMR) suffers from severe traffic congestion, as do many other large-scale urban areas around the world. A possible solution to this issue, which has been suggested by transportation, economics and environmental researchers, is the implementation of a congestion charging system. One of the objectives of this project is to establish clear concepts and shed light on the main issues regarding these systems by means of a comprehensive literary review. It is expected that this project may help the development of in-depth studies carried in order to evaluate the viability and impacts of congestion charging proposals. In order to achieve this goal, many subjects are addressed, such as the definition of congestion, how its measured, the theoretical backgrounds that support congestion charging schemes, their different degrees of differentiation, which policies were enacted in order to reduce traffic congestion in São Paulo, what considerations and studies have already been developed for Brazil and São Paulo regarding these systems and where have these systems been successfully installed. Later chapters deal with another goal of this project: estimating how a congestion charging system would affect SPMR. This was achieved through a multinomial logit model, where decision-makers choose between \"Public Transportation\" and \"Private Automobile\". The results presented at this phase are merely indicative of certain tendencies and should not be considered final. This project also attempts to show that given the available Automated Fare Collection (AFC) data and Automated Vehicle Location (AVL) data, it is possible to estimate the current public transportation system\'s unused capacity. The author shows this by calculating the capacity of one bus trip using these data, but also explains the difficulties of expanding this analysis to the whole of SPMR\'s public transportation system.
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A Decentralized Approach to Dynamic Collaborative Driving CoordinationDao, Thanh-Son 18 August 2008 (has links)
This thesis presents a novel approach to several problems in
intelligent transportation systems using collaborative driving
coordination. With inter-vehicle communication and intelligent
vehicle cooperation, important tasks in transportation such as lane
position determination, lane assignment and platoon formation can be
solved. Several topics in regard to inter-vehicle communication,
lane positioning, lane assignment and platoon formation are explored
in this thesis:
First, the design and experimental results of low-cost lane-level
positioning system that can support a large number of transportation
applications are discussed. Using a Markov-based approach based on
sharing information among a group of vehicles that are traveling
within the communication range of each other, the lane positions of
vehicles can be determined. The robustness effectiveness of the
system is shown in both simulations and real road tests.
Second, a decentralized approach to lane scheduling for vehicles
with an aim to increase traffic throughput while ensuring the
vehicles exit successfully at their destinations is presented. Most
of current traffic management systems do not consider lane
organization of vehicles and only regulate traffic flows by
controlling traffic signals or ramp meters. However, traffic
throughput and efficient use of highways can be increased by
coordinating driver behaviors intelligently. The lane optimization
problem is formulated as a linear programming problem that can be
solved using the Simplex method.
Finally, a direction for cooperative vehicle platoon formation is
proposed. To enhance traffic safety, increase lane capacities and
reduce fuel consumption, vehicles can be organized into platoons
with the objective of maximizing the travel distance that platoons
stay intact. Toward this end, this work evaluates a proposed
strategy which assigns vehicles to platoons by solving an
optimization problem. A linear model for assigning vehicles to
appropriate platoons when they enter the highway is formulated.
Simulation results demonstrate that lane capacity can be increased
effectively when platooning operation is used.
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A Decentralized Approach to Dynamic Collaborative Driving CoordinationDao, Thanh-Son 18 August 2008 (has links)
This thesis presents a novel approach to several problems in
intelligent transportation systems using collaborative driving
coordination. With inter-vehicle communication and intelligent
vehicle cooperation, important tasks in transportation such as lane
position determination, lane assignment and platoon formation can be
solved. Several topics in regard to inter-vehicle communication,
lane positioning, lane assignment and platoon formation are explored
in this thesis:
First, the design and experimental results of low-cost lane-level
positioning system that can support a large number of transportation
applications are discussed. Using a Markov-based approach based on
sharing information among a group of vehicles that are traveling
within the communication range of each other, the lane positions of
vehicles can be determined. The robustness effectiveness of the
system is shown in both simulations and real road tests.
Second, a decentralized approach to lane scheduling for vehicles
with an aim to increase traffic throughput while ensuring the
vehicles exit successfully at their destinations is presented. Most
of current traffic management systems do not consider lane
organization of vehicles and only regulate traffic flows by
controlling traffic signals or ramp meters. However, traffic
throughput and efficient use of highways can be increased by
coordinating driver behaviors intelligently. The lane optimization
problem is formulated as a linear programming problem that can be
solved using the Simplex method.
Finally, a direction for cooperative vehicle platoon formation is
proposed. To enhance traffic safety, increase lane capacities and
reduce fuel consumption, vehicles can be organized into platoons
with the objective of maximizing the travel distance that platoons
stay intact. Toward this end, this work evaluates a proposed
strategy which assigns vehicles to platoons by solving an
optimization problem. A linear model for assigning vehicles to
appropriate platoons when they enter the highway is formulated.
Simulation results demonstrate that lane capacity can be increased
effectively when platooning operation is used.
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Analysis and Design of Vehicular NetworksWu, Hao 18 November 2005 (has links)
Advances in computing and wireless communication technologies have increased interest in smart vehicles, vehicles equipped with significant computing, communication and sensing capabilities to provide services to travelers. Smart vehicles can be exploited to improve driving safety and comfort as well as optimize surface transportation systems. Wireless communications among vehicles and between vehicles and roadside infrastructures represent an important class of vehicle communications.
One can envision creating an integrated radio network leveraging various wireless technologies that work together in a seamless fashion. Based on cost-performance tradeoffs, different network configurations may be appropriate for different environments. An understanding of the properties of different vehicular network architectures is absolutely necessary before services can be successfully deployed. Based on this understanding, efficient data services (e.g., data dissemination services) can be designed to accommodate application requirements.
This thesis examines several research topics concerning both the evaluation and design of vehicular networks.
We explore the properties of vehicle-to-vehicle (v2v) communications. We study the spatial propagation of information along the road using v2v communications. Our analysis identifies the vehicle traffic characteristics that significantly affect information propagation. We also evaluate the feasibility of propagating information along a highway.
Several design alternatives exist to build infrastructure-based vehicular networks. Their characteristics have been evaluated in a realistic vehicular environment. Based on these evaluations, we have developed some insights into the design of future broadband vehicular networks capable of adapting to varying vehicle traffic conditions.
Based on the above analysis, opportunistic forwarding that exploit vehicle mobility to overcome vehicular network partitioning appears to be a viable approach for data dissemination using v2v communications for applications that can tolerate some data loss and delay. We introduce a methodology to design enhanced opportunistic forwarding algorithms. Practical algorithms derived from this methodology have exhibited different performance/overhead tradeoffs.
An in-depth understanding of wireless communication performance in a vehicular environment is necessary to provide the groundwork for realizing reliable mobile communication services. We have conducted an extensive set of field experiments to uncover the performance of short-range communications between vehicles and between vehicles and roadside stations in a specific highway scenario.
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Corpos em trânsito : um estudo sobre o assédio sexual nos transportes coletivos de AracajuSantos, Maria da Conceição 09 1900 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Everyday women are harassed while accessing public spaces. However, this harassment is
mistakenly regarded as a compliment or “getting hit on”. Within this background, it is possible
to show how the genre differences are orchestrated in order to produce inequalities while
sharing public spaces. This essay aims to understand how the naturalization of sexual
harassment may affect women’s lives, and how society reacts in sexual harassment situations.
The main question asked: what enables harassment on women? In order to answer that, I
collected several testimonies of women who were suffered harassment episodes while using
Aracaju’s public transportation system. Also, through field report and passenger interviews, I
aim to identify if such conduct is recognized as inappropriate. / Cotidianamente as mulheres são assediadas ao acessarem o espaço público. No entanto essa
conduta é naturalizada e entendida como “cantada” ou elogio. Diante disso é possível indicar
como as diferenças de gênero são articuladas para produzir desigualdades no compartilhamento
do espaço público. Assim, esta dissertação objetiva compreender como a naturalização do
assédio sexual pode afetar a vida das mulheres e, como a sociedade reage diante de tais situações
de violência sexual. Colocando-se como questão central: o que possibilita as mulheres serem
assediadas? Para tanto, vali-me de relatos de mulheres que passaram por experiências de assédio
sexual no transporte público de Aracaju. Além disso, através das observações em campo e das
entrevistas com os passageiros, pretende-se identificar se essa conduta é reconhecida como
inadequada. / São Cristóvão, SE
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Contribuições ao estudo de implantação de pedágio urbano em São Paulo. / Contributions towards the study of congestion charging systems in São Paulo.Felipe Ferreira Dias 01 April 2015 (has links)
A Região Metropolitana de São Paulo (RMSP) sofre de sérios problemas de congestionamento, assim como muitas outras cidades de grande porte. Uma possível solução, proposta por pesquisadores de transportes, economia e ciências ambientais, é a implantação de um sistema de congestion charging, chamada no Brasil de pedágio urbano. Um dos objetivos do presente trabalho foi estabelecer os conceitos relacionados a este assunto e ilustrar as principais questões relacionadas à sua implantação. Espera-se que este trabalho possa auxiliar o desenvolvimento de estudos de avaliação da viabilidade e de impactos de sistemas propostos de congestion charging. Para atingir este objetivo, toca-se em diversos assuntos, como a definição de congestionamento e as formas de medi-lo, a base conceitual e teórica dos sistemas de congestion charging e seus diversos esquemas de diferenciação. São expostas também as medidas de mitigação de congestionamento que já foram implantadas na RMSP, quais foram os estudos já desenvolvidos considerando este tipo de política para a RMSP, e casos em que sistemas de congestion charging já foi implantado. Neste trabalho, desenvolveu-se também um modelo de escolha discreta a partir dos dados da Pesquisa Origem e Destino 2007 do METRÔ, onde pessoas deveriam escolher entre \"Transporte Coletivo\" e \"Transporte Público\". Este modelo foi utilizado para avaliar o potencial de impacto na divisão modal e de arrecadação de um congestion charge aplicado ao centro expandido de São Paulo. Adverte-se, porém, que os resultados obtidos são meramente ilustrativos. Mostra-se, também, que é possível avaliar a capacidade ociosa do sistema de transporte coletivo a partir dos dados disponíveis de bilhetagem e de GPS dos ônibus. Este processo é exemplificado através do cálculo de capacidade de uma única viagem de um único ônibus, dada a dificuldade de automatização deste processo para abranger toda a frota. / The São Paulo Metropolitan Region (SPMR) suffers from severe traffic congestion, as do many other large-scale urban areas around the world. A possible solution to this issue, which has been suggested by transportation, economics and environmental researchers, is the implementation of a congestion charging system. One of the objectives of this project is to establish clear concepts and shed light on the main issues regarding these systems by means of a comprehensive literary review. It is expected that this project may help the development of in-depth studies carried in order to evaluate the viability and impacts of congestion charging proposals. In order to achieve this goal, many subjects are addressed, such as the definition of congestion, how its measured, the theoretical backgrounds that support congestion charging schemes, their different degrees of differentiation, which policies were enacted in order to reduce traffic congestion in São Paulo, what considerations and studies have already been developed for Brazil and São Paulo regarding these systems and where have these systems been successfully installed. Later chapters deal with another goal of this project: estimating how a congestion charging system would affect SPMR. This was achieved through a multinomial logit model, where decision-makers choose between \"Public Transportation\" and \"Private Automobile\". The results presented at this phase are merely indicative of certain tendencies and should not be considered final. This project also attempts to show that given the available Automated Fare Collection (AFC) data and Automated Vehicle Location (AVL) data, it is possible to estimate the current public transportation system\'s unused capacity. The author shows this by calculating the capacity of one bus trip using these data, but also explains the difficulties of expanding this analysis to the whole of SPMR\'s public transportation system.
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Schedule and Cost Performance Analysis and Prediction in Louisiana DOTDHamide, Mahmoud 19 May 2017 (has links)
Many construction projects in the United States are facing the risk of cost overrun and schedule delays. This is also happening here in the State of Louisiana. When these things happen, it causes cost overrun which can then be passed on to the tax payers and may also cause the state to take on less projects than they normal. Many researchers have studied the reasons behind both the cost overrun and the delays resulting in private firms, developing project management tools and best practices to prevent this risk. In this research, I aim to study the historical trend in 2912 publically funded projects in the State of Louisiana. The study will reveal the overall state level of accuracy of forecasting cost and schedule. A forecasting formula based on those historical projects will be developed to assist estimators at the Parish level in predicting cost and schedule performance.
The State of Louisiana has so many projects that deal with the transportation system (roadway, bridges, drainage, traffic sign, traffic signal, lighting etc...)
My Dissertation will be a study and analysis of time and cost of the projects in LADOTD, whether the projects finish on time, before time or after time as well as the cost of the project that has been completed overrun or underrun or the exact amount that the bid amount was. With this study and analysis, my intention is to create time schedule and cost to be used to on reaching accuracy on finishing the project on time and the exact bid amount of the project (exclude whether condition, extra work, and some unexpected problems that may arise during the length of the project).
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Problematika fungování potrubní přepravy v rámci světových obchodních operací s plynem a ropou / Problems of pipeline functioning in global business oil and gas operationsShtanko, Elizaveta January 2011 (has links)
Under the current intensive development of the world economy, there is a significant increase in integration of strategic sectors in countries towards the regional and international networks. Therefore, the potential of pipeline transport begins to take special foreign economic and geopolitical importance. The current status and development of this field is the object of an increased interest of all parties that are involved in the transport of raw materials. The more trades there are with oil and gas, the more issues related to its transport are occurred which all parties involved in the transport system faced to deal with. In the context of rapidly developing interconnection of global economies on regional level along with its undeniable reflection on international situation, it makes the functioning of already existing system of pipelines and realization of new projects related to construction of pipelines, with issues of economic, ecological and technical character that play an important role in delivering strategic energy products to world markets. At the same time the strong competition for the construction of pipeline facilities increases its geopolitical significance.
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Návrh systému automatické výměny vřetenových hlav / Design of automatic exchange of spindle headsSrněnský, Jan January 2017 (has links)
The purpose of this thesis is to design system for automatic exchange of spindle heads shared by several machines. Spindle heads are transported between these machines and placed to the position for exchange. The system also allows storing of heads. Requirements for system are load capacity of 2 000 kg and placing a spindle head to the exchange position with precision of ± 0,02 mm. The thesis consists of three parts. The first part involves search of head exchange principles and shows possible ways to transport heads and other elements that could be used in the system. In the next part are several possible solutions introduced and the selection of the best one is made. The last part contains the design of the chosen solution, visualisation, description and calculations. The result is design of two solutions which are described in this work.
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Estimation et analyse spatiales des émissions de polluants de transports individualisés : évaluation des performances environnementales d'un Transport à la Demande / Spatial estimating and analyse of exhaust emissions from individual transports : Assessment of the environmental performance of a demand responsive transportPrud'homme, Julie 25 October 2013 (has links)
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. / The Demand Responsive Transport (DRT) is a transportation system which offers a collective use of motor vehicles, in opposite of personal vehicles use. Between the functioning of taxis and classical public transport, it offers a service that is flexible in time and space like taxis, promoting the sharing of vehicles, like public transports. It is why it is present as a solution for a sustainable mobility. In the minds, DRT are often associated to a reduction of exhaust emissions and so are developed in rural areas. However, is grouping travellers enough to make DRT gainful for environment?In this doctoral research, an assessment tool of the environmental impact of DRT systems has been developed. To ensure that choice is sustainable in the sense of sustainable development, the service must be adapted to the local context by minimising emissions of substances in the near atmosphere while maintaining a sufficient quality of service when competing against personal vehicle use. A parameter directly involved in pollutant emissions, is often overlooked in approaches: the road network. We therefore search for identify laws and thresholds relating to pollutant emissions generated by the functioning of a DRT: how the road network does it affect the environmental performance of DRT or on the skill to grouping customers in vehicles? Depending on what service features (time windows allowed)? More generally, is that the optimization of the same type of DRT is equivalent to a road network to another, from the perspective of pollutant emissions? As any integrated tool to perform this task is available, we have developed a geomatics processing to estimate the quantities of pollutants emitted on road sections within the particular functioning of DRT and to cartography it to analyse their spatial distribution. This tool combines a GIS to an exhaust emissions model that we have adapted to our questioning (GREEN-DRT).
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