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Comportamento dinâmico de um veículo implementado com suspensões ativasCorrêa, Juliano Lourega January 2011 (has links)
O objetivo do trabalho é melhorar o controle do comportamento dinâmico sob excitação vertical de um modelo veicular completo levando em consideração os três movimentos principais, de elevação (heave), balanço (pitch) e de rolagem (roll), em termos de aceleração. Com essa finalidade desenvolve-se a programação necessária para implementação de um modelo de veículo completo de 7 GDL no programa MATLAB® que interage com o sistema de controle ativo desenvolvido em diagrama de blocos no programa Simulink®. Em seguida, o desempenho do modelo é avaliado através de programas desenvolvidos de excitações de estrada com perfil senoidal e randômico. Os resultados obtidos mostram que o movimento da massa suspensa, em termos de aceleração, acima e abaixo do valor da frequência natural da roda pode ser diminuído pela filtragem dos coeficientes de mola e amortecimento através de um laço de controle interno, mais a utilização de amortecimento skyhook das velocidades de elevação, balanço e rolagem com um laço de controle externo. A atenuação das constantes de mola abaixo da frequência do corpo do veículo reduz as perturbações da estrada, mas podem bater nos limitadores do percurso da suspensão. / The aim of this work is to improve the control of the dynamic behavior under vertical excitation of a full vehicular model whilst taking into consideration the three main movements of heave, pitch and roll in terms of acceleration. With this goal in mind, the necessary programming was carried out for the implementation of a full vehicular model of 7 DOF using the software MATLAB® which interacts with the active control system developed via blocks diagram using the software Simulink®. Following on from that, the performance of the model is evaluated by means of programmes developed from road excitations with a sinusoidal and random profile. The results show that the motion of the sprung mass, in terms of acceleration, above and below the natural frequency of the wheel can be reduced by filtering the spring and damping coefficients through an internal control loop, plus the usage of skyhook damping of heave, pitch and roll velocities with an external control loop. The mitigation of the spring constants below the frequency of the body of the vehicle reduces the excitations of the road, but may strike against the path limiters of the suspension.
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Comportamento dinâmico de um veículo implementado com suspensões ativasCorrêa, Juliano Lourega January 2011 (has links)
O objetivo do trabalho é melhorar o controle do comportamento dinâmico sob excitação vertical de um modelo veicular completo levando em consideração os três movimentos principais, de elevação (heave), balanço (pitch) e de rolagem (roll), em termos de aceleração. Com essa finalidade desenvolve-se a programação necessária para implementação de um modelo de veículo completo de 7 GDL no programa MATLAB® que interage com o sistema de controle ativo desenvolvido em diagrama de blocos no programa Simulink®. Em seguida, o desempenho do modelo é avaliado através de programas desenvolvidos de excitações de estrada com perfil senoidal e randômico. Os resultados obtidos mostram que o movimento da massa suspensa, em termos de aceleração, acima e abaixo do valor da frequência natural da roda pode ser diminuído pela filtragem dos coeficientes de mola e amortecimento através de um laço de controle interno, mais a utilização de amortecimento skyhook das velocidades de elevação, balanço e rolagem com um laço de controle externo. A atenuação das constantes de mola abaixo da frequência do corpo do veículo reduz as perturbações da estrada, mas podem bater nos limitadores do percurso da suspensão. / The aim of this work is to improve the control of the dynamic behavior under vertical excitation of a full vehicular model whilst taking into consideration the three main movements of heave, pitch and roll in terms of acceleration. With this goal in mind, the necessary programming was carried out for the implementation of a full vehicular model of 7 DOF using the software MATLAB® which interacts with the active control system developed via blocks diagram using the software Simulink®. Following on from that, the performance of the model is evaluated by means of programmes developed from road excitations with a sinusoidal and random profile. The results show that the motion of the sprung mass, in terms of acceleration, above and below the natural frequency of the wheel can be reduced by filtering the spring and damping coefficients through an internal control loop, plus the usage of skyhook damping of heave, pitch and roll velocities with an external control loop. The mitigation of the spring constants below the frequency of the body of the vehicle reduces the excitations of the road, but may strike against the path limiters of the suspension.
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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 renewableEdson Elpidio Neto 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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An Efficient QoS MAC for IEEE 802.11p Over Cognitive Multichannel Vehicular NetworksEl Ajaltouni, Hikmat January 2012 (has links)
One of the most challenging issues facing vehicular networks lies in the design of an
efficient MAC protocol due to mobile nature of nodes, delay constraints for safety applications and interference. In this thesis, I propose an efficient Multichannel QoS Cognitive MAC (MQOG). MQOG assesses the quality of channel prior to transmission employing dynamic channel allocation and negotiation algorithms to achieve significant increase in channel reliability,
throughput and delay constraints while simultaneously addressing Quality of Service.
The uniqueness of MQOG lies in making use of the free unlicensed bands. To consider
fair effective sharing of resources I propose a Mobility Based Dynamic Transmit Opportunity
(MoByToP) while modifying the 802.11e TXOP (Transmit Opportunity). The proposed protocols were implemented in OMNET++ 4.1, and extensive experiments demonstrated a faster and more efficient reception of safety messages compared to existing VANet MAC Protocols. Finally, improvements in delay, packet delivery ratios and throughput were noticed.
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A Lane Detection, Tracking and Recognition System for Smart VehiclesLu, Guangqian January 2015 (has links)
As important components of intelligent transportation system, lane detection and tracking (LDT) and lane departure warning (LDW) systems have attracted great interest from the computer vision community over the past few years. Conversely, lane markings recognition (LMR) systems received surprisingly little attention. This thesis proposed a real-time lane assisting framework for intelligent vehicles, which consists of a comprehensive module and simplified module. To the best of our knowledge, this is the first parallel architecture that considers not only lane detection and tracking, but also lane marking recognition and departure warning. A lightweight version of the Hough transform, PPHT is used for both modules to detect lines. After detection stage, for the comprehensive module, a novel refinement scheme consisting of angle threshold and segment linking (ATSL) and trapezoidal refinement method (TRM) takes shape and texture information into account, which significantly improves the LDT performance. Also based on TRM, colour and edge informations are used to recognize lane marking colors (white and yellow) and shapes (solid and dashed). In the simplified module, refined MSER blobs dramatically simplifies the preprocessing and refinement stage, and enables the simplified module performs well on lane detection and tracking. Several experiments are conducted in highway and urban roads in Ottawa. The detection rate of the LDT system in comprehensive module average 95.9% and exceed 89.3% in poor conditions, while the recognition rate depends on the quality of lane paint and achieves an average accuracy of 93.1%. The simplified module has an average detection rate of 92.7% and exceeds 84.9% in poor conditions. Except the conventional experimental methods, a novel point cluster evaluation and pdf analysis method have been proposed to evaluate the performance of LDT systems, in terms of the stability, accuracy and similarity to Gaussian distribution.
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Relay Selection for Heterogeneous Transmission Powers in Connected VehiclesAlotaibi, Maryam January 2017 (has links)
It is widely believed that the advances of Vehicle-to-Vehicle (V2V) communications will help to remodel the prospect of road transportation systems. By virtue of V2V communications, information generated by the vehicle control system, on-board sensors or passengers can be effectively disseminated among vehicles in proximity, or to vehicles in multiple hops away in a vehicular ad-hoc network (VANET). Without assistance from any built infrastructure, a variety of active road safety applications (e.g., Vehicle-Based Road Condition Warning, Cooperative Collision Warning, Approaching Emergency Vehicle Warning) and traffic efficiency management applications (e.g., Wrong Way Driver Warning) are enabled by inter-vehicle wireless links. The purpose of connecting vehicle technologies is to improve road safety, awareness, and transportation systems efficiency.
The Wireless Access for Vehicular Environments (WAVE) technology/Dedicated Short-Range Communications (DSRC) is the main enabling wireless technology for both V2V and vehicle-to-Infrastructure (V2I) communications. From USDOT and stakeholders detailed analysis, it is resolved that WAVE is the only viable option for critical safety and other low latency mobility and environmental applications. WAVE technology has reached to a mature stage and a basic V2V system is expected to be deployed in the next few years. In the late part of 2015, USDOT announce that WAVE is sufficiently robust to proceed with the preparation for deployment of connected vehicle environments. The USDOT has created a roadmap with preliminary plans to guide industries and public agencies implementation efforts. However, there are persisting major concerns regarding the V2V initiative needing more analysis and testing. One of the concerns is the channel congestion. Channel congestion may impact WAVE effectiveness, which may in turn impact the effectiveness of supported safety applications. Suggested solutions to mitigate congestion are focused on supporting adaptive control of the message transmission power. The Institute of Electrical and Electronics Engineers (IEEE), and European Telecommunications Standards Institute (ETSI) have included transmit power component per packet to be used for channel congestion control mechanism. The adjustment of transmission powers has created an environment of vehicles with different transmission powers. Such environment will affect the performance of the proposed protocols to disseminate warning messages. It may also affect the performance of periodic beaconing that is required by most of the safety applications. Thus far, several protocols have been proposed to help identify appropriate relay vehicles. However, such approaches neglect the fact that vehicle transmission ranges are typically heterogeneous due to different transmission power values or dynamic adjustment of power to alleviate congestion. The proper selection of relay nodes governs high delivery ratio, acceptable overall end-to-end delay and efficient bandwidth usage. In this work, area-based relay selection protocols that work in heterogeneous transmission powers are introduced. Mathematical functions are developed for a timer and decision probability to be used by each vehicle receiving the message. The values of the two functions allow the vehicle to determine if it is the next to act as relay node or not. Geometric taxonomy for all possible overlap patterns in wireless environment is constructed with the related math calculations. Moreover, an adaptive expiry time for neighbours-table entries that harmonizes with dynamic beacon scheduling is proposed.
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A Quality Guaranteed Video Dissemination Protocol over Urban Vehicular Ad Hoc NetworksLi, Yang January 2014 (has links)
Video dissemination over Vehicular Ad Hoc Networks (VANETs) is an attractive technology which supports many novel applications. Hence, the merit of this thesis has twofold. Firstly, we evaluate and compare three routing techniques and two error resilience techniques. We select a sender-based routing technique called SUV and compare it with the other two selected receiver-based routing techniques named REACT-DIS and CDS. The results, more specifically, show that the receiver-based solutions outperform the sender-based solution. In addition, only CDS method fulfils the general quality requirements as it is the best that reduces redundancy packets and covers the whole topology. The results also indicate that the video coding scheme, Interleaving, can fix the multiple consecutive packet losses and guarantee reliable video qualities over VANETs. Network Coding, however, fails to provide satisfactory video quality for urban scenarios. This study next combines the selected receiver based routing techniques and the two error resilience techniques. We find the best combination is Interleaving over CDS. Secondly, we design a quality guaranteed video dissemination protocol for urban VANETs scenarios. Based on our comparison result, our protocol selects the CDS and Interleaving as the routing and error resilient techniques. To fix the single packet loses caused by the topology’s intermittent disconnection and collisions, we propose a store-carry-broadcast scheme for the nodes to re-transmit the local buffer saved packets. The results, when compared to the selected techniques and combinations, show that our proposed protocol is the most efficient one in terms of packet delivery, delay, overhead and video quality.
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A Design and Evaluation of a Secure Neighborhood Awareness Framework for Vehicular Ad-Hoc NetworksAbumansoor, Osama January 2014 (has links)
Vehicular ad-hoc networks (VANETs) are envisioned to provide many road and safety applications that will improve drivers' awareness and enhance the driving experience. Many of proposed applications are location-based that depend on sharing the location information of vehicles and events among neighboring nodes. The location-based applications should provide vehicle operators with knowledge of the current surrounding conditions to help them make appropriate traveling decisions, such as avoiding traffic congestion. Drivers expect to receive accurate and reliable information from other vehicles. Therefore, securing localization service integrity is important to support a VANET's overall system reliability.
In this thesis, we study the exchanged location information in VANETs and designed a framework to prevent potential security threats that will violate users' privacy and overcome limitations that can impact the exchanged data integrity and reliability. The solution developed a secure neighborhood awareness service and shared localization information management protocol in a VANET. The proposed framework is constructed through several components: (i) a location verification protocol that will secure location information by providing a non-line-of-sight (NLOS) verification protocol to overcome moving obstacle effects; (ii) privacy-preserving location information management to detect data inconsistency and provide a recovery process while preventing attackers from tracking individual vehicles; (iii) a trust model evaluation mechanism based on neighborhood awareness; (iv) an adaptive beacon protocol that will reduce the number of messages and provide quality of service(QoS) control for network managers and authorities. We also propose a security evaluation model that quantifies the security attributes for the localization service in a VANET. The model will help evaluate an integrated security measures that are provided by different components of the network services.
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Cooperative Vehicular Communications for High Throughput Applications / 大容量車載アプリケーションに向けた車車間協調通信Taya, Akihiro 24 September 2019 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(情報学) / 甲第22099号 / 情博第709号 / 新制||情||122(附属図書館) / 京都大学大学院情報学研究科通信情報システム専攻 / (主査)教授 守倉 正博, 教授 原田 博司, 教授 梅野 健 / 学位規則第4条第1項該当 / Doctor of Informatics / Kyoto University / DFAM
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Service Car ExpressAndrade Ccalluche, Mayra Alexsandra, Maximiliano Dominguez, Lusian, Reyes Santa Cruz, Katherine Dora, Yrrazabal Acosta, Ruty Ines 17 July 2018 (has links)
El presente trabajo corresponde al curso de Desarrollo de Negocios 2, a lo largo del desarrollo aplicaremos conceptos y herramientas aprendidas a lo largo de la carrera de la Universidad Peruana de Ciencias Aplicadas.
Actualmente el Perú presenta un crecimiento paulatino en el parque automotor, con mayor concentración en Lima Metropolitana y Callao. Muestra de ello se puede apreciar a simple vista en la cotidianidad, siendo específicos el tráfico.
Service Car Express, plantea la idea de negocios que apunta al sector automotriz, al cuidado de los vehículos y asesoramiento vehicular. Nuestra idea está dirigida al NSE B y C y a personas o empresas que cuenten con vehículos considerados de segunda mano o a aquellos que estén planeando adquirir un vehículo dentro de distritos como Miraflores, Surco, Chorrillos, Barranco, San Miguel, Surquillo y Jesús María.
Service Car Express, llega con una propuesta de valor diferente a la que está acostumbrado el cliente, servicios netamente a domicilio buscando reducir el tiempo perdido de nuestros clientes y volviendo esa parte de sus vidas tan tediosa de ir al taller en algo simplemente práctico e innovador, disponible en el momento.
Con la finalidad de cumplir esta propuesta de valor, ScarX ha creado un modelo de negocios que a través de la tecnología por aplicativos busca optimizar los tiempos de servicios que pueda brindar a sus clientes, de este modo buscara alcanzar la máxima calidad y perfeccionar sus procesos operacionales identificando y aprovechando todos sus recursos disponibles. / The present work corresponds to the course of Business Development 2, throughout the development we will apply concepts and tools learned throughout the career of the UPC University.
Currently, Peru presents a gradual growth in the automotive fleet, with a greater concentration in Lima Metropolitana and Callao. Sample of this can be seen in everyday life, when see traffic everywhere.
Service Car Xpress, raises the business idea that points to the automotive sector, car care and vehicle advice. Our idea is directed to B and C socioeconomic status and to people or companies that have vehicles considered second-hand or to those who are planning to acquire a vehicle within districts such as Miraflores, Surco, Chorrillos, Barranco, San Miguel, Surquillo and Jesús María.
Service Car Xpress, arrives with a different value proposition, services purely at home trying to reduce the lost time of our customers while they are in workshops, we are going to make it be something simply practical and innovative, available at the time.
In order to fulfill this value proposition, ScarX has created a business model that, through technology is going to optimize the time a car service can take. We offer our clients the highest quality in all processes taking advantage of all available resources. / Trabajo de investigación
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