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Propuesta de mejoramiento de los niveles de servicio en la intersección de las avenidas Primavera y Velasco Astete mediante la aplicación de tecnologías basadas en el uso de Sistemas Inteligentes de Transporte (ITS) / Improvement proposal of levels of service at Primavera and Velasco Astete node through the Intelligent Transportation Systems (ITS) applicationEscobedo Zavala, Ronnie André, Estela Cifuentes, Jesús Antonio 12 December 2019 (has links)
La presente tesis consiste en la investigación y desarrollo de la implementación de las tecnologías ITS para mejorar la transitabilidad en la intersección de las avenidas Primavera y Velasco Astete. Esta implementación está orientada a la disminución de la congestión vehicular en la intersección a través de una mejor gestión del tráfico sin la necesidad de implementar infraestructuras viales basadas en obras civiles, como ampliación de carriles, creación de viaductos, pasos a desnivel, entre otros, las cuales requieren una mayor inversión de capital. Es por esta razón que el objeto de esta tesis está en la propuesta de la mejora de la situación actual del tráfico en el escenario en estudio con la implementación de las tecnologías ITS mediante su simulación en el software Aimsun v8.2.
Para ello, se estudiaron los niveles de servicio según los conceptos establecidos por la metodología HCM 2010.
La implementación de los ITS en el escenario estudiado permitió una reducción promedio de 150 segundos en el tiempo de demora, los factores de la cola media y densidad vehicular también presentaron mejoras. Asimismo, el nivel de servicio, luego del análisis de resultados realizado, presentó una mejora significativa al pasar de una clasificación F a una clasificación C en la intersección principal estudiada.
Finalmente, del análisis de costos realizado, a través de la asociación a los factores de valor social del tiempo, VHMD y tiempo de viaje, se obtuvo que la implementación de los ITS en la intersección representaría un beneficio de S/. 1,227.77 / km.hora.pasajeros promedio. / This thesis consists of the research and development of the implementation of ITS technologies to improve the passability at the intersection of Primavera and Velasco Astete avenues. This implementation is aimed at reducing vehicular congestion at the intersection through better traffic management without the need to implement road infrastructure based on civil works, such as extension of lanes, creation of viaducts, overpasses, among others, which require a greater capital investment. It is for this reason that the purpose of this thesis is in the proposal to improve the current traffic situation on the stage under study with the implementation of ITS technologies through its simulation in the Aimsun v8.2 software.
For this, the service levels were studied according to the concepts established by the HCM 2010 methodology.
The implementation of ITS in the scenario studied allowed an average reduction of 150 seconds in the delay time, the factors of the average tail and vehicle density also showed improvements. Likewise, the level of service (LOS), after the analysis of the results, presented a significant improvement when passing from an F classification to a C classification at the main intersection studied.
Finally, from the cost analysis carried out, through the association with the social value factors of time, VHMD and travel time, it was obtained that the implementation of STIs at the intersection would represent a benefit of S /. 1,227.77 / km. Hour. Average passengers. / Tesis
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Evaluación de la precisión para el método de sostenibilidad en el tiempo en intersecciones urbanas / Evaluation of accuracy for the sustainability method in time for urban intersectionsBurga-Álvarez Llorca, Oswaldo Ayrton, Medina Sánchez, Fabricio Ramiro 23 June 2020 (has links)
Una manera de evaluar si las soluciones para intersecciones urbanizadas son sostenibles en el tiempo, es calculando las demoras para un tránsito futuro y la presente investigación determina la precisión de dicha evaluación. La demora vehicular es uno de los parámetros más importantes utilizado para evaluar el rendimiento de las intersecciones semaforizadas, por tal motivo, profesionales del transporte usan como criterio de optimización del tráfico, la disminución de las demoras. En este artículo, se presenta un enfoque para evaluar la precisión del método de sostenibilidad en el tiempo para intersecciones urbanas, para lo cual se analizarán las demoras en una intersección para diferentes escenarios. Primero, se modelará la intersección de estudio mediante el software Synchro 10. En segundo lugar, el modelo se aplicará para diversos escenarios donde el volumen vehicular incrementará dependiendo del crecimiento vehicular. Se demuestra que, a partir de las demoras obtenidas para cada escenario, se puede estimar la precisión de aplicar la solución que se desee en una intersección, esto en base a la tendencia de la curva de variación porcentual de las demoras en el tiempo. En resumen, la metodología puede ser aplicada en diferentes intersecciones urbanizadas y escenarios donde se pretenda plantear soluciones que sean sostenibles en el tiempo. / A way to evaluate if the solutions for urban intersections are sustainable in time, is about calculating the delays for a future traffic and the present investigation establishes the accuracy of that evaluation. The vehicular delay is one of the most important parameters that is used to evaluate the performance of traffic light intersections, for this reason, professionals of transport use as traffic optimization judgment the decrease of delays. This article presents an approach to evaluate the accuracy for the sustainability method in time for urban intersections, for which this investigation analyzes the delays in one intersection for different stages. This project begins with a model of the intersection of study helped by the software Synchro 10. Then, the model will be applied for many stages where the vehicular volume will be increased depending the vehicular growth. Finally, it is proved that due to the estimated delays for each stage, it will be possible to estimate the accuracy of applying a desired solution in an intersection, that is based on the trend of percentages variation curve on time delays. In brief, the methodology could be applied in different urban intersections and stages where it is pretended to propose solutions that are sustainable over the time. / Trabajo de investigación
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Study on Reliable Vehicular Communication for Urban and Highway Traffic MobilityNadella, Sai Anoop, Araga, Nikhil Reddy January 2016 (has links)
Due to its extensive applications, VANETs had emerged as one of the important research areas in wireless networks. The main motto of vehicular technologies is to enhance traffic management by improving safety and also provide a reliable data exchange and information services among vehicles. Vehicular communications is a co-operative technology that enables communication among different vehicles, infrastructure and other devices. V2V, V2I communication models are commonly used in vehicular networks. Recently, extensive research is being performed on hybrid model which integrates both V2V and V2I models. The main goal of this research is to study the nature of these communication models in an urban and highway traffic environment and suggest a simulated model which helps to which provide reliable vehicular communication. Literature study helps to gain knowledge on the background of vehicular networks. Later, a simulated model is designed with the help of SUMO and NS-3 which implements all these communication models. The simulated model which is developed is classified into different phases and each phase represents a different communication model. Each phase is completely different from one another. All these phases are incorporated in both urban and highway traffic environments. Performance metrics are evaluated and analyzed to study the behavior of these models. Throughput, PDR, Packet-Drop and Propagation-Delay are the performance metrics considered. Simulation analysis shows that hybrid model exhibits a stable communication behavior when compared with V2V and V2I in both urban and highway traffic environments.
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An Approach for Receiver-Side Awareness Control in Vehicular Ad-Hoc NetworksDíez Rodríguez, Víctor, Detournay, Jérôme January 2016 (has links)
Vehicular Ad-Hoc Network (VANET)s are a key element of Intelligent Transport System (ITS)s. One of the challenges in VANETs is dealing with awareness and congestion due to the high amount of messages received from the vehicles in communication range. As VANETs are used in critical applications, congestion on the receiver side caused by the buffering of the packets is a safety hazard. In this thesis, we propose a stream-wise queuing system on the receiver side and show how it improves the timeliness of the messages received and main- tains the awareness of the system in a congestion situation.
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Impacto de la restricción vehicular sobre la calidad del aire : lecciones para Santiago de ChileSepúlveda Witt, Guillermo 07 1900 (has links)
Seminario para optar al título de Ingeniero Comercial, Mención Economía / Desde la implementación del Plan de Prevención Descontaminación Atmosférica de la Región Metropolitana en 1998, la restricción vehicular (RV) ha sido una de las medidas angulares para combatir los altos niveles de polución del aire que sufre Santiago de Chile. Sin embargo, en tiempos recientes la efectividad e idoneidad de la medida ha sido cuestionada por expertos y el público en general por igual. En este trabajo se desarrolla un marco de los factores de múltiple naturaleza que determinan la polución atmosférica, el cual permite prever el impacto potencial de la RV según el contexto. Posteriormente, mediante una regresión de mínimos cuadrados ordinarios y un diseño de regresión discontinua, se analiza la evidencia de la efectividad de la RV en disminuir los niveles de MP10 y CO en Santiago, analizando por separado el formato original de 1998 y la posterior actualización de 2007. Los resultados indican que, en un principio, la RV fue efectiva en disminuir los niveles de ambos contaminantes. Sin embargo, la medida se ha vuelto inefectiva, observándose un aumento de la polución tras la actualización de 2007. En base a esto resultados, se analizan posibles explicaciones a la perdida de efectividad de la RV, como, por ejemplo, el excesivo aumento del parque automotriz o de hogares con más de un vehículo. Finalmente, se analizan posibles enfoques para tratar la polución del aire proveniente de fuentes móviles de manera efectiva, y se entrega una propuesta de plan estratégico.
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Caracterização preliminar das emissões de aldeídos e ácidos carboxílicos em veículos do ciclo Otto e do ciclo Diesel com uso de combustíveis fósseis e renováveis / Preliminary characterization of emissions of aldehydes and carboxylic acids in vehicles Otto and Diesel cycle with the use of fossil fuels and renewableElpidio Neto, Edson 01 July 2009 (has links)
O crescimento excessivo da frota veicular mundial tem feito com que milhares de toneladas de poluentes sejam lançadas na atmosfera diariamente em todo o globo, no Brasil a frota de veículos atingiu aproximadamente 54 milhões de unidades, e tem aumentado significativamente em vários estados, segundo o DETRAN (Departamento Estadual de Transito de São Paulo) o estado conta hoje com aproximadamente 19,5 milhões de veículos, 6,5 milhões só na capital, onde são emplacados aproximadamente mil veículos por dia, este crescimento tem causado episódios críticos de poluição do ar nos centros urbanos. Dentre os poluentes lançados na atmosfera de origem veicular, encontram-se os aldeídos e os ácidos carboxílicos, (objetos de estudo deste trabalho), essas substâncias são de suma importância para saúde humana, e participam nas reações fotoquímicas de formação de ozônio na baixa troposfera. Desde a implantação do PROCONVE (Programa de Controle de Poluição do Ar por Veículos Automotores) em 1988, medidas como a redução dos limites de emissão, novas tecnologias na fabricação de veículos automotores, redução da porcentagem de enxofre no diesel, combustíveis renováveis, entre outras, e programas como a Inspeção veicular na cidade de São Paulo criada a partir de 2009, tem sido tomadas visando à constante melhoria na qualidade do ar. Dentre os combustíveis renováveis atualmente utilizados, o biodiesel tem se destacado, tendo em vista o grande consumo de diesel utilizado como fonte de energia no Brasil. Atualmente foram incorporados 2% de biodiesel ao diesel comercial, e antecipando a meta para 2013, possivelmente já no ano de 2010 a porcentagem será de 5%. O objetivo deste trabalho é a caracterização preliminar de aldeídos e ácidos carboxílicos na emissão de veículos do ciclo Otto e do ciclo diesel, utilizando combustíveis fósseis e renováveis. Para a realização deste trabalho foram utilizados três veículos, sendo dois do ciclo Otto e um do ciclo diesel. Os testes foram realizados em dinamômetro de chassis conforme norma ABNT NBR 6601 e ABNT NBR 12026, o método para amostragem dos ácidos carboxílicos foi validado e estabelecido conforme item 6.2 deste trabalho. Nos veículos do ciclo Otto, foram utilizados como combustíveis, a gasolina pura, gasolina com 22% de AEAC (Álcool etílico anidro combustível) e AEHC (álcool etílico hidratado combustível). No veículo do ciclo diesel foram utilizados como combustíveis o diesel comercial com 2% de biodiesel e biodiesel puro de soja. Os resultados obtidos indicaram uma emissão de ácidos carboxílicos 2,5 vezes maior para os testes realizados com os veículos do ciclo Otto, e 5,5 vezes superior para os aldeídos nos resultados dos testes realizados com o veículo do ciclo diesel. A média de todos os resultados obtidos na realização deste trabalho com os veículos do ciclo Otto e do ciclo diesel, utilizando combustíveis fósseis e renováveis, indicaram emissão 3,2 vezes superior dos poluentes pesquisados na utilização de combustíveis renováveis. Estudos com maior número de amostras, e diversificações nas categorias dos veículos devem ser realizados a fim de se detalhar o perfil destes poluentes na emissão veicular com o uso de combustíveis fósseis e renováveis. / The global automotive fleet is emitting thousands of tons of air pollutants daily all over the planet; in Brazil, the domestic fleet reached 54 million vehicles. According to DETRAN (São Paulo state traffic department), the state of São Paulo has 19,5 million vehicles and 6,5 million in São Paulo city, where a thousand new vehicles daily are registered. This fleet growing up is causing critical air pollution situations in metropolitan areas. Among the major automotive air pollutants are aldehydes and carboxylic acids, both are the subject of this study. These substances play an important role for human health and they take place at photochemical reactions generating ozone in low troposphere. Since the beginning of PROCONVE (National Automotive Pollution Control Regulation) in 1988, measures has been taken like emission regulation, development of new automotive technologies, reduction of sulfur content in diesel fuel, renewable fuels and inspection of in use vehicles. Among the fuels from renewable sources currently in use, the biodiesel plays an important role, because diesel is the most used energy source. Currently, with the enforcement of the law number 11097, from January 13rd of 2005, 2% of biodiesel must be added in the commercial diesel and until 2013 this addition will rise to 5%. The subject of this study is the determination of emission profile of aldehydes and carboxylic acids in vehicles powered by Otto and diesel engines using fossil and renewable fuels. In this study were used three vehicles, two of them powered by Otto engines and one sample with diesel engine. The tests were performed in vehicle chassis dynamometer in accordance of the standards ABNT NBR 6601 and ABNT NBR 12026. The method for sampling and evaluation of carboxylic acids was validated and established in article 6.2 of this study. Otto vehicles were tested with 100% gasoline, gasoline plus 22% of anhydrous ethanol and 100% Ethanol. Diesel vehicle were tested with commercial diesel plus 2% biodiesel and 100% soy biodiesel. The results indicates an average 3,2 times higher emission of aldehydes and carboxylic acids when the samples were tested with renewable fuels. Tests with a higher number of samples and variation in vehicle types should be performed in order to provide a more precise profile of these pollutants emission using fossil and renewable fuels.
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Hybrid DES-based Vehicular Network Simulator with Multichannel OperationsWang, Le 16 April 2019 (has links)
Vehicular Ad-hoc Network (VANET) is considered to be a viable technology for inter- vehicle communications for the purpose of improving road safety and efficiency. The En- hanced Distribution Channel Access (EDCA) mechanism and multichannel operations are introduced to ensure the Quality of Service (QoS). Therefore, it is necessary to create an accurate vehicular network simulator that guarantees the vehicular communications will work as described in the protocols. A comprehensive vehicular network simulator should consider the interaction between mobility models and network protocols. In this dissertation, a novel vehicular network simulation environment, VANET Toolbox, designed using discrete-event system (DES) is presented. The APP layer DES Module of the proposed simulator integrates vehicular mo- bility operations with message generation functions. The MAC layer DES module supports single channel and multichannel EDCA operations. The PHY layer DES module supports bit-level processing. Compared with packet-based simulator such as NS-3, the proposed PHY layer is more realistic and accurate. The EDCA scheme is evaluated and compared with the traditional Carrier-Sensing Mul- tiple Access (CSMA) scheme, with the simulations proving that data with different priorities can coexist in the same channel. The multichannel operation for the EDCA scheme is also analyzed in this dissertation. The multichannel switching operation and coordination may cause packet dropping or increased latency to the communication. The simulations show that with heavy network traffic, multichannel communication performs better than single channel communication. From the perspective of safety-related messages, the multichannel operation is able to isolate the interference from the non-safety messages in order to achieve a better packet delivery rate and latency. On the other hand, the non-safety messages can achieve high throughput with reasonable latency from multichannel communication under heavy load traffic scenario.
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Network Coding in Multihop Wireless Networks: Throughput Analysis and Protocol DesignYang, Zhenyu 29 April 2011 (has links)
Multi-hop wireless networks have been widely considered as promising approaches to provide more convenient Internet access for their easy deployment, extended coverage, and low deployment cost. However, providing high-speed and reliable services in these networks is challenging due to the unreliable wireless links, broadcast nature of wireless transmissions, and frequent topology changes. On the other hand, network coding (NC) is a technique that could significantly improve the network throughput and the transmission reliability by allowing intermediate nodes to combine received packets. More recently proposed symbol level network coding (SLNC), which combines packets at smaller symbol scale, is a more powerful technique to mitigate the impact of lossy links and packet collisions in wireless networks. NC, especially SLNC, is thus a particular effective approach to providing higher data rate and better transmission reliability for applications such as mobile content distribution in multihop wireless networks. This dissertation focuses on exploiting NC in multihop wireless networks. We studied the unique features of NC and designed a suite of distributed and localized algorithms and protocols for content distribution networks using NC and SLNC. We also carried out a theoretical study on the network capacity and performance bounds achievable by SLNC in mobile wireless networks. We proposed CodeOn and CodePlay for popular content distribution and live multimedia streaming (LMS) in vehicular ad hoc networks (VANETs), respectively, where many important practical factors are taken into consideration, including vehicle distribution, mobility pattern, channel fading and packet collision. Specifically, CodeOn is a novel push based popular content distribution scheme based on SLNC, where contents are actively broadcast to vehicles from road side access points and further distributed among vehicles using a cooperative VANET. In order to fully enjoy the benefits of SLNC, we proposed a suite of techniques to maximize the downloading rate, including a prioritized and localized relay selection mechanism where the selection criteria is based on the usefulness of contents possessed by vehicles, and a lightweight medium access protocol that naturally exploits the abundant concurrent transmission opportunities. CodePlay is designed for LMS applicaitions in VANETs, which could fully take advantage of SLNC through a coordinated local push mechanism. Streaming contents are actively disseminated from dedicated sources to interested vehicles via local coordination of distributively selected relays, each of which will ensure smooth playback for vehicles nearby. CodeOn pursues a single objective of maximizing downloading rate, while CodePlay improves the performance of LMS service in terms of streaming rate, service delivery delay, and bandwidth efficiency simultaneously. CodeOn and CodePlay are among the first works that exploit the features of SLNC to simplify the protocol design whilst achieving better performance. We also developed an analytical framework to compute the expected achievable throughput of mobile content distribution in VANETs using SLNC. We presented a general analytical model for the expected achievable throughput of SLNC in a static wireless network based on flow network theory and queuing theory. Then we further developed the model to derive the expected achievable accumulated throughput of a vehicle driving through the area of interest under a mobility pattern. Our proposed framework captures the effects of multiple practical factors, including vehicle distribution and mobility pattern, channel fading and packet collision, and we characterized the impacts of those factors on the expected achievable throughput. The results from this research are not only of interest from theoretical perspective but also provide insights and guidelines on protocol design in SLNC-based networks.
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Vehicular Dynamic Spectrum Access: Using Cognitive Radio for Automobile NetworksChen, Si 12 December 2012 (has links)
"Vehicular Dynamic Spectrum Access (VDSA) combines the advantages of dynamic spectrum access to achieve higher spectrum efficiency and the special mobility pattern of vehicle fleets. This dissertation presents several noval contributions with respect to vehicular communications, especially vehicle-to-vehicle communications. Starting from a system engineering aspect, this dissertation will present several promising future directions for vehicle communications, taking into consideration both the theoretical and practical aspects of wireless communication deployment. This dissertation starts with presenting a feasibility analysis using queueing theory to model and estimate the performance of VDSA within a TV whitespace environment. The analytical tool uses spectrum measurement data and vehicle density to find upper bounds of several performance metrics for a VDSA scenario in TVWS. Then, a framework for optimizing VDSA via artificial intelligence and learning, as well as simulation testbeds that reflect realistic spectrum sharing scenarios between vehicle networks and heterogeneous wireless networks including wireless local area networks and wireless regional area networks. Detailed experimental results justify the testbed for emulating a mobile dynamic spectrum access environment composed of heterogeneous networks with four dimensional mutual interference. Vehicular cooperative communication is the other proposed technique that combines the cooperative communication technology and vehicle platooning, an emerging concept that is expected to both increase highway utilization and enhance both driver experience and safety. This dissertation will focus on the coexistence of multiple vehicle groups in shared spectrum, where intra-group cooperation and inter-group competition are investigated in the aspect of channel access. Finally, a testbed implementation VDSA is presented and a few applications are developed within a VDSA environment, demonstrating the feasibility and benefits of some features in a future transportation system."
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[en] ENVIRONMENT COMPUTATIONAL FOR INTEGRATION OF THE SIMULATION AND OF THE VISUALISATION FOR THE DYNAMICS OF VEHICLES / [pt] AMBIENTE COMPUTACIONAL PARA INTEGRAÇÃO DA SIMULAÇÃO E DA VISUALIZAÇÃO DA DINÂMICA DE VEÍCULOSERNANDES PEREIRA DE OLIVEIRA 08 August 2003 (has links)
[pt] Este trabalho tem como objetivo apresentar um ambiente
computacional integrado para a simulação e visualização
tridimensional da dinâmica de veículos, o SVDV. O ambiente
está dividido em três módulos: interface gráfica, simulação
e visualização gráfica. O módulo de interface, desenvolvido
em Visual Basic, gerencia os bancos de dados e serve como
ligação entre os módulos de simulação e visualização
gráfica. O módulo de simulação permite a inclusão de
diferentes modelos de dinâmica de veículos, estando
disponíveis atualmente modelos em Matlab/Simulink, Visual
C++ e MS Excel. O módulo de visualização gráfica faz
uso da poderosa linguagem de programação Maxscript, que
emprega scripts do 3D Studio Max (3DS Max). Com esta
linguagem é possível incluir inúmeros efeitos de
iluminação, texturização e modelagem, disponíveis no 3DS
Max, garantindo um elevado grau de realismo na visualização
da simulação. / [en] This work presents na integrated computational system for
the simulation and visualization of vehicular dynamics,
SVDV. The system is divided in three modules: graphics
interface, simulation and graphics visualization. The
interface module, developed in Visual Basic, manages the
databases and behaves as a link between the simulation and
visualization modules. The simulation module allows
the inclusion of different vehicular dynamics models. At
the present stage there are models developed in
Matlab/Simulink, Visual C++ and MS Excel. The graphics
visualization module makes use of the powerful Maxscript
programming language, a script language from 3D Studio Max
(3DS Max). Hence, it is possible to incorporate a variety
of illumination and texture effects and also modeling
techniques from 3DS Max, thus guaranteeing a realistic
visualization.
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