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Predeterminantes de sobrevivência em vítimas de acidentes de trânsito submetidas a atendimento pré-hospitalar de suporte avançado à vida; Survival determinant factors in motor vehicle crash victms submitted to prehospital advanced life support

Malvestio, Marisa Aparecida Amaro
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 15/12/2005 PT
Relevância na Pesquisa
36.22%
O Atendimento Pré Hospitalar (APH) é um importante recurso no atendimento à vítimas de trauma. No entanto, há muitas dificuldades para demonstrar o efeito benéfico das intervenções do APH na sobrevivência das vítimas, sobretudo as de suporte avançado à vida (SAV). A proposta deste estudo é caracterizar as vítimas de acidentes trânsito, com Revised Trauma Score (RTS) <11, atendidas pelo SAV municipal e encaminhadas a hospitais terciários em São Paulo, além de identificar as variáveis da fase pré-hospitalar associadas à sobrevivência e avaliar o valor predeterminante dessas variáveis sobre o resultado obtido pelas vítimas. As variáveis avaliadas foram: sexo, idade, mecanismos do acidente, procedimentos de suporte básico e SAV realizados, repercussão fisiológica do trauma na cena do acidente, (considerando o RTS , seus parâmetros e flutuações), o tempo consumido no APH, gravidade do trauma segundo o Injury Severity Score (ISS),a Maximum Abbreviated Injury Scale (MAIS) e número de lesões para cada segmento corporal. Os resultados obtidos por 175 vítimas entre 12 e 65 anos, foram submetidos a ”Análise de Sobrevivência de Kaplan Meier” e ao “Modelo de Riscos Proporcionais de Cox”. A variável dependente foi o tempo de sobrevivência após o acidente...

Controle robusto multivariável para um veículo submersível autônomo.; Multivariable robust control for an autonomous underwater vehicle.

Cutipa Luque, Juan Carlos
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 02/03/2007 PT
Relevância na Pesquisa
36.17%
Este trabalho trata do controle dos movimentos de um Veículo Submersível Autônomo (VSA). Veículos submersíveis são difíceis de controlar devido à alta não linearidade de seus modelos, ao forte acoplamento de movimentos, ao desconhecimento de certas dinâmicas, às incertezas do próprio modelo, devido a distúrbios externos impostos pelo ambiente e devido ao ruído de sensores. A dificuldade de controle pode ser exacerbada quando o veículo é subatuado. Para realização deste trabalho foi escolhido um VSA do tipo torpedo, cujo modelo matemático disponível na literatura foi devidamente modificado para garantir uma melhor descrição de seus movimentos em seis graus de liberdade (6-GL). O modelo foi então validado através de simulações numéricas. Para a síntese dos controladores utilizou-se uma técnica de controle avançada. Mais especificamente, utilizou-se a abordagem do controle H1 para sistemas multivariáveis. Assim foram obtidos controladores centralizados capazes de superar o problema do forte acoplamento de movimentos. Técnicas de controle avançado permitem também considerar as informações disponíveis sobre perturbações, incertezas, ruídos e diferentes tipos de entrada já na fase de síntese, o que permite obter controladores com desempenho adequado numa ampla faixa de operação. Neste trabalho...

Sistemas multicorpos avançados: modelamento da interação dinâmica entre veículo e via permanente de metrô; Advanced multibody systems: modelling the dynamics interaction between vehicle and permanente way of metro

Candeloro, Lucas Pinotti
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 06/05/2015 PT
Relevância na Pesquisa
36.12%
Nos dias de hoje, a simulação dinâmica de veículos metroviários tem sido um importante método de análise e verificação, tanto no âmbito de projeto, como na engenharia de manutenção. Os pacotes de simulação disponíveis no mercado são altamente desenvolvidos e podem ser adaptados para os mais diversos cenários. O presente trabalho tem por objetivo demonstrar a funcionalidade destes programas, fundamentando a teoria por trás de seu algoritmo computacional, de maneira a expandir a fronteira de conhecimento nas engenharias de projeto e de manutenção. Para isso, são efetuados dois estudos de caso: passagem de veículo em região de abertura de bitola em curva de raio constante; passagem de veículo em sequencia de curvas reversas. Sendo assim, esta dissertação apresenta uma visão geral sobre o estado da arte na simulação da interação veículo e via permanente.; Nowadays, the dynamic simulation of metro vehicles have been an important method of analysis and verification in design engineering as in maintenance engineering. The simulation packages available are highly developed and can be adapted for different scenarios. This paper aims to demonstrate the functionality of these programs, supporting the theory behind its computational algorithm...

Mobile application as a tool for urban traffic data collection and generation to advanced traveler information systems using Wi-Fi networks available in urban centers

Dezani, Henrique; Damiani, Furio; Marranghello, Norian; Viudes, Ulysses; Parra, Ícaro Augusto
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Conferência ou Objeto de Conferência Formato: 288-292
ENG
Relevância na Pesquisa
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This paper presents an Advanced Traveler Information System (ATIS) developed on Android platform, which is open source and free. The developed application has as its main objective the free use of a Vehicle-to- Infrastructure (V2I) communication through the wireless network access points available in urban centers. In addition to providing the necessary information for an Intelligent Transportation System (ITS) to a central server, the application also receives the traffic data close to the vehicle. Once obtained this traffic information, the application displays them to the driver in a clear and efficient way, allowing the user to make decisions about his route in real time. The application was tested in a real environment and the results are presented in the article. In conclusion we present the benefits of this application. © 2012 IEEE.

Busca tabu aplicada ao problema de roteamento de veiculos com coleta e entrega; A tabu search for the vehicle routing problem with pickup and delivery

Elias Goraieb
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 14/10/2005 PT
Relevância na Pesquisa
36.12%
Este trabalho aborda o problema de roteamento de veículos com coleta e entrega, visando à minimização do número de veículos utilizado e a distância total percorrida. O pedido de serviço é atendido por um veículo na janela de tempo imposta pelo cliente, e envolve uma coleta na origem que precede a entrega no destino. A capacidade dos veículos é limitada e uma rota tem duração máxima. Um algoritmo de busca tabu é proposto para a resolução deste problema. Diversas estratégias avançadas são incorporadas ao algoritmo, tais como redução de vizinhança, diversificação da busca, e utilização da metodologia path relinking; This work considers the vehicle routing problem with pickup and delivery with the objectives of minimizing the fleet size and the total traveI distance. Each service request is served by a vehicle within time windows imposed by the clients, and involves a pickup origin that precedes a delivery destination. The capacity of the vehicle and the total route duration are limited. A tabu search algorithm is proposed to solve this problem. Several advanced strategies are incorporated in the algorithm, such as neighborhood reduction, search diversification, and path relinking

Special Vehicle Operations: An Activity-Based Plan for Improving the Automotive Vehicle Development Process

Scott, Gregory
Fonte: MIT - Massachusetts Institute of Technology Publicador: MIT - Massachusetts Institute of Technology
Formato: 1044045 bytes; application/pdf
EN_US
Relevância na Pesquisa
36.39%
This brief paper considers the New Product Development (NPD) strategies and practices recently employed by the Ford Motor Company as a base for a substantial, near-term improvement in automotive vehicle development performance. The recognition of current industry "best practices" in lean design and manufacturing coupled with consumer desires for niche vehicles provides an opportunity to significantly reduce the time-to-market for new vehicle designs. This paper proposes that a Special Vehicle Operations plant be established as an ongoing facility to develop and manufacture technology demonstration vehicles for corporate research use and public sale. Such a facility, a manufacturing "proving ground" akin to vehicle test facilities, would support the more rapid introduction of advanced vehicle technologies by routinizing design experiments in a quasi-mass production setting. The expected result would be a steadier and more continuous introduction of advanced processes into mainstream products. The scheduling, technical, financial, and quality risks inherent to such introductions would be lessened as well. The research foundation of this paper is an International Motor Vehicle Program-sponsored report supervised by Professor Michael Cusumano of MIT on the NPD practices under implementation by the Ford Motor Company. Other primary source materials include articles on advanced product development initiatives taking place in the automobile industry.

Hydrogen : what fuel cell vehicles and advanced nuclear reactors have in common

Demirdöven, Nurettin, 1974-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 104 p.; 5506898 bytes; 5512523 bytes; application/pdf; application/pdf
ENG
Relevância na Pesquisa
36.06%
This thesis reports on two technology and policy issues directly related to hydrogen economy. The first issue concentrates on the end-use application of hydrogen as a transportation fuel, and deals with the following question: what is the place of hydrogen fuel cell vehicles among the new, more-efficient advanced vehicle technologies. Our analysis indicates that fuel cell vehicles using hydrogen from fossils fuels offer no significant energy efficiency advantage over hybrid vehicles in urban driving cycle. Therefore, there is a strong justification for federal support for hybrid vehicles that will achieve similar results, quicker. The second issue focuses on another important technology and policy question related to large scale hydrogen production: are there any comparative efficiency, cost and/or political advantages of using an advanced nuclear reactor coupled to a thermochemical conversion plant to produce hydrogen with respect using a conventional nuclear reactor coupled to an electrolysis plant? The results suggest that given the existing technical and cost uncertainties, developing an advanced nuclear reactor technology solely for the use of thermochemical hydrogen production is not good energy (R&D) policy. Electrolysis is a more promising alternative provided a more efficient electrolysis technology can be coupled to an advanced nuclear energy (i.e. electricity) source at a reasonable cost. Therefore...

Evaluating the impact of advanced vehicle and fuel technologies in U.S. light duty vehicle fleet

Bandivadekar, Anup P
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 182 p.
ENG
Relevância na Pesquisa
46.35%
The unrelenting increase in oil use by the U.S. light-duty vehicle (LDV) fleet presents an extremely challenging energy and environmental problem. A variety of propulsion technologies and fuels have the promise to reduce petroleum use and greenhouse gas (GHG) emissions from motor vehicles. Previous work in this domain has compared individual vehicle or fuel alternatives. The aim of this research was to deepen the understanding of the likely scale and timing of the fleet-wide impact of emerging technologies. A model of the light-duty vehicle fleet showed that fuel consumption of mainstream gasoline internal combustion engine (ICE) technology vehicles will determine the trajectory of fleet fuel use and GHG emissions over the next two decades. Using vehicle simulations and historical data, the trade-off between vehicle performance, size and fuel consumption was quantified. It was shown that up to 26 percent reduction in future LDV fuel use is possible with mainstream gasoline ICE vehicles alone if emphasis of vehicle technology is on reducing fuel consumption rather than improving performance. Addressing this vehicle performance-size-fuel consumption trade-off should be the priority for policymakers. By considering both supply and demand side constraints on building up vehicle production rates...

Breathing Clean : Considering the Switch to Natural Gas Buses

Kojima, Masami
Fonte: Washington, DC: World Bank Publicador: Washington, DC: World Bank
EN_US
Relevância na Pesquisa
36.12%
In response to emerging epidemiological evidence of the toxicity of diesel vehicular emissions, there is growing interest in substituting conventional diesel with much cleaner natural gas in cities where ambient concentrations of particulate matter are markedly higher than what is internationally considered acceptable. This paper compares the performance of natural gas and conventional diesel buses, and outlines the barriers to the adoption of natural gas buses in developing countries. In the absence of emissions standards that effectively require natural gas, natural gas-fueled buses are unlikely to be adopted because they are more expensive to operate relative to diesel buses. The social case for replacing diesel with natural gas a fuel for buses rests on environmental grounds. If a local government decides that the reduction in air pollution associated with the substitution of conventional diesel with natural gas for use in buses is worth the cost, then it needs to adopt policies to encourage the switch to natural gas. These might include emissions standards for buses...

Effects of ITS implementations - INMS and ATIS - on greenhouse gas and air quality emissions in an urban road corridor, assessed using an instrumented probe vehicle and microsimulation modelling

Taylor, M.; Zito, R.; Woolley, J.
Fonte: CD-ROM Paper 6403 Publicador: CD-ROM Paper 6403
Tipo: Conference paper
Publicado em //2003 EN
Relevância na Pesquisa
36.08%
This paper reports on the use of a real instrumented probe vehicle and virtual probe vehicles generated using microsimulation in order to study the impacts on emissions of Intelligent Transport Systems (ITS) systems for incident management (INMS) and real time advanced traveler (driver) information (ATIS) in an urban corridor comprising a freeway and a parallel arterial road.; http://ntlsearch.bts.gov/tris/record/tris/00970755.html; M.A.P. Taylor, R. Zito and J.E. Woolley

On-Board Vehicle Tracking and Behavior Anticipation for Advanced Driver Assistance Systems

Alin, Andreas Berthold
Fonte: Universität Tübingen Publicador: Universität Tübingen
Tipo: Dissertação
EN
Relevância na Pesquisa
36.44%
This thesis develops a probabilistic vehicle tracking and behavior anticipation system for advanced driver assistance systems. Advanced Driver Assistance System(s) (ADAS) need to know where other vehicles in the surrounding of the ego-vehicle are or will be in a few seconds, in order to maintain a safe driving state by activating evasive actions or issuing warnings to the driver in the event of a critical situation. The difficulty of this task are the uncertainties in driver behavior and sensor readings. Since sensors are never accurate and behavior cannot be predicted exactly, the internal estimate of the surrounding world state has to be modeled probabilistically. In contrast to most state-of-the-art approaches in the vehicle tracking domain, this thesis represents the uncertainty of an individual vehicle position estimate by a probabilistic grid representation also known as a Bayesian Histogram Filter (BHF). This representation handles multi-modal distributions by saving the probability in individual grid cells and propagates them through the grid by model assumptions that simulate real-world vehicle kinematics and driver behavior. In this thesis, first, the probabilistic position and velocity representation by the grid cells is discussed...

Acquisition streamlining: a viable method for accelerated procurement of the advanced amphibious assault vehicle

Clark, James W., Jr.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado Formato: 105 p.
EN_US
Relevância na Pesquisa
36.15%
Approved for public release; distribution is unlimited; Acquisition streamlining is enjoying increased attention since procurement of weapon systems has become more complex and lengthy from identification of a Mission Need Statement (MNS) to deployment of the system. Streamlining is required by directives governing the acquisition process for the Department of Defense, yet procurement remains quite cumbersome in execution. This thesis goes beyond streamlining the acquisition cycle and provides methods of accelerating the procurement process within current laws and directives. Using the Marine Corps' Advanced Amphibious Assault Vehicle Program as an example, the researcher discovered that strategies exist which can specifically be tailored to accelerate procurement of the AAAV without adding prohibitive program risk. To implement these methods tailoring of the acquisition cycle to specifically fit the unique characteristics of the AAAV is required. While there is no prohibition against tailoring the acquisition cycle to specific programs, the Department of Defense tends to be very risk averse with respect to acquisition of weapon systems. The AAAV represents a weapon system that is uniquely poised for acceleration of the acquisition cycle through tailoring. Recognition by DOD that there is a legitimate need for accelerating procurement of the AAAV...

A comparison of heavy lift launch vehicle options for the 1990's

Schreiber, Jonathan K.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado Formato: v, 70 p.;28 cm.
EN_US
Relevância na Pesquisa
36.22%
This thesis compares attributes of the heavy lift launch vehicle options that are available for the United States to use in support of the Space Exploration Initiative. The systems compared are the Advanced Launch System, Shuttle-C, Saturn V/F-1 and Energia. The F-1 development history is presented along with the proposed development of the ALS and Shuttle-C. Advantages and disadvantages of each of the systems are presented and possible trade-offs between them are discussed. The thesis shows that the option that is most cost effective and can be used to support the deployment of Space Station Freedom is that of developing a booster with a core engine like the F-1. In conclusion, a recommendation is given as to what the best option, with regard to both short and long term mission requirements, is for a new heavy lift launch vehicle for the United States.; US Navy (USN) author

Analysis of current Department of Defense risk management practices in weapon system acquisition : a case study of the Advanced Amphibious Assault Vehicle (AAAV) PDRR and SDD risk management practices

Bailey, Robert O.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Thesis; Thesis Formato: xvi, 135 p. : ill. (some col.) ;
Relevância na Pesquisa
36.4%
Approved for public release; distribution in unlimited.; Approved for public release; distribution in unlimited.; This thesis discusses risk in Department of Defense (DoD) weapon systems acquisition. It uses the Marine Corps' Advanced Amphibious Assault Vehicle (AAAV) as a case study in risk management strategy and techniques. The AAAV will provide the Marine Corps with a fast deploying, over-the-horizon, waterborne insertion capability. The AAAV's improvements over the currently fielded Amphibious Assault Vehicle (AAV) will provide Marines with a highly survivable and lethal weapon system ashore. Risk is the possibility of damage, inj ury or loss. The severity of a risk is determined by a combination of both the probability of an unfavorable event occurring and the severity of the event's occurrence. Risks are present in virtually all DoD developmental programs. Programs suffer from risks in technical challenges, unstable system requirements, missing schedule milestones, unpredictable funding and cost overruns. The DoD currently uses techniques to mitigate risks inherent in advanced system development. This thesis analyzes the AAAV's Program Definition and Risk Reduction (PDRR) acquisition phase risk management strategy. The thesis concludes by drawing from the lessons learned in the AAAV program during PDRR and analyzing the application of the lessons learned during the AAAV's cu rrent acquisition phase...

Cost benefit analysis of government furnished equipment versus contract furnished equipment for the procurement and integration of the MK-44 chain gun with the United States Marine Corps Expeditionary Fighting Vehicle; Cost benefit analysis of government furnished equipment versus contract furnished equipment for the procurement and integration of the MK-44 chain gun with the United States Marine Corps Expeditionary Fighting Vehicle

Howard, James E.; Collins, Patrick B.; Howard, James E.; Collins, Patrick B.
Fonte: Monterey California. Naval Postgraduate School; Monterey California. Naval Postgraduate School Publicador: Monterey California. Naval Postgraduate School; Monterey California. Naval Postgraduate School
Tipo: Thesis; Thesis Formato: xiv, 77 p. : col. ill.; xiv, 77 p. : col. ill.
Relevância na Pesquisa
36.32%
MBA Professional Report; Approved for public release, distribution is unlimited; MBA Professional Report; Approved for public release, distribution is unlimited; The Direct Reporting Program Manager (DRPM) for the USMC's Expeditionary Fighting Vehicle (EFV) is conducting an analysis of two acquisition tactics concerning the commercial procurement of the MK-44 to be integrated with the EFV. The EFV is manufactured by General Dynamics (GD) and the MK-44 chain gun is manufactured by Alliant Techsystems Inc. (ATK). The analysis is the topic of this thesis and will assist the DRPM in determining which of two tactics the Government should use for the procurement of the MK-44. The two arrangements of acquiring and integrating the MK-44 are 1) to procure the MK-44 as government furnished equipment (GFE) or 2) to procure the MK-44 as contractor furnished equipment (CFE). The fundamental difference is that a GFE arrangement will provide a direct contractual relationship between the Government and ATK, whereas, a CFE contract will eliminate that relationship as ATK will become a sub-contractor to GD, the prime contractor for the EFV. These two options present a variety of issues, both tangible and intangible, for analysis in determining which approach is most advantageous...

A case study of the application of reliability centered maintenance (RCM) in the acquisition of the advanced amphibious assault vehicle (AAAV)

Garza, Luis
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado Formato: x, 73 p.
Relevância na Pesquisa
36.24%
Approved for public release, distribution is unlimited; This thesis examined the application of Reliability Centered Maintenance (RCM) in the acquisition of the Marine Corps' Advanced Amphibious Assault Vehicle (AAAV). RCM is referred to throughout various service and DoD wide references, but in the absence of specific guidance on how to apply RCM to an acquisition, the AAAV program provided a unique opportunity to analyze key decisions and results. The research included an examination of the RCM process to include RCM training provided on site at the AAAV program, a review of pertinent program documents, interviews with program representatives, and an analysis of the critical decision to utilize the RCM process. The key findings of the research effort concluded that when RCM is applied to an acquisition with program commitment, the program will gain a greater, more focused understanding of the system and subsystems, than with the traditional Failure Modes and Effects Analysis (FMEA) and Failure Modes, Effects and Criticality Analysis (FMECA). AAAV also demonstrated that RCM benefits were broad and not limited to just maintenance analysis and that these benefits could be gained at any stage of the acquisition. This thesis concludes by recommending that the acquisition community recognize the benefits and institutionalize RCM into the acquisition process.; Captain...

Modelagem e controle de trajetória de um veículo robótico terrestre de exterior; Modeling and path tracking control of an outdoor robotic ground vehicle

Rafael de Angelis Cordeiro
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 24/05/2013 PT
Relevância na Pesquisa
36.09%
Veículos terrestres autônomos tem recebido uma atenção especial dos estudos de robótica nos últimos anos. Suas aplicações incluem segurança na condução, exploração de locais inóspitos e automatização agrícola. O enfoque deste trabalho situa-se no projeto VERO, em parceria com o CTI, e tem por objetivo o desenvolvimento de aplicações de controle de trajetória para um veículo do tipo todo-terreno. Para tal, um modelo completo (dinâmico e tridimensional) é desenvolvido, com uma atenção especial para os modelos de interação entre solo e pneu, responsáveis pelas forças não lineares atuantes sobre o veículo. Em seguida, dois modelos reduzidos e linearizados são obtidos e estes são utilizados para a síntese de controladores LQR. Uma comparação entre os controladores é realizada e a resposta de um deles é detalhada para uma análise sobre a influência das características do modelo veicular sobre o controle do veículo. Por fim, três abordagens são propostas para melhorar a resposta obtida pelos controladores.; Autonomous ground vehicles have received special attention from robotics studies in past years. Their applications include advanced driver assistance systems (ADAS), exploration of inhospitable environments and harvest autonomous machines. In partnership with CTI...

Metaheuristica para a solução de problemas de roteamento de veiculos com janela de tempo; Metaheuristics for the solution of vehicle routing problems with time windows

Heloisa Passarelli Vieira
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 11/12/2008 PT
Relevância na Pesquisa
36.09%
Nos últimos anos, diversas heurísticas e meta-heurísticas foram propostas para o Problema de Roteamento de Veículos com Janela de Tempo (PRVJT), cujo objetivo é determinar a rota a ser seguida por uma frota de veículos para servir um número de clientes em um dado intervalo de tempo, sem violar a capacidade dos veículos. Cada cliente é visitado por exatamente um veículo e somente uma vez. Esta disertação apresenta um estudo das técnicas utilizadas para o PRVJT, dando ênfase para os Algoritmos Genéticos. Diversos tipos de cruzamento e esquemas de mutação, além de outras técnicas avançadas, tal como o Hill-Climbing, são analisados. Para o algoritmo que implementamos, são apresentados vários resultados numéricos baseados em um conjunto de 56 problemas, cada qual com 100 clientes, proposto por Solomon. O desempenho do algoritmo que implementamos também é comparado aos melhores resultados publicados na literatura.; In recent years, several heuristic and metaheuristic methods were proposed for the Vehicle Routing Problem with Time Windows (VRPTW). The objective of the problem is to serve a set of customers within a given time interval, without violating the capacity of the vehicles. Each customer must be visited once and by only one vehicle. This dissertation presents a survey on the techniques used to solve the VRPTW...

Advanced vehicle safety and content distribution system

B, Anita; Sheril, Beena; E, Ramesh B.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 07/06/2014
Relevância na Pesquisa
46.33%
Advanced vehicle content distribution system (ACDS)is complemented by improved network connectivity with Mobile Network 3G, 4G network. Advanced content distribution system uses Access Points deployed along roadside. APs co-ordinate and collaborate to distribute content to vehicles in mobility. The infrastructure of deployed APs solves real time issues like predicting errors in movement, limited information shared to vehicles on movement due to limited resources. The advances vehicle content distribution system structures APs in to form a map which is considering the vehicle contact pattern which is analyzed by APs. The system is more effective by optimizing the network consumption by sharing prefectched data between APs. The process depends on APs storage, bandwidth and load on the origin APs which is connected to internet. With the features Advanced System to distribute the content the system takes care of improving road safety, delivery accuracy and important content distribution.; Comment: 4 pages, 2 figures, Published with International Journal of Engineering Trends and Technology (IJETT)

Lateral guidance control of a low-speed vehicle

Sahin, Haydar
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Tese de Doutorado
EN_US
Relevância na Pesquisa
36.15%
This thesis examines the lateral guidance control of a low-speed vehicle. Several topics are studied in detail: (1) vehicle error-state model for lateral guidance based on Ackerman steering and (2) lateral guidance control of a low-speed vehicle using fuzzy logic. Independently written research papers address each topic. The first paper presents a second order "error-state" kinematic model based on Ackerman steering appropriate for studying the lateral guidance control of low-speed vehicles traversing on roads of constant curvature. Lateral guidance control of vehicles is of great interest to the Advanced Vehicle Control Systems (AVCS) Division of the Intelligent Transportation System (ITS) community. Both linear and nonlinear models are derived in detail. The error states considered are the vehicle's lateral error and heading error measured with respect to the instantaneous road centerline tangent. In addition to the derivation, both simulation and experimental results are presented with very good correspondence being achieved. The second paper investigates the performance of several different controllers used to perform lateral guidance control of a low-speed vehicle described as a linear nonminimum-phase "error-state" bicycle model based on Ackerman steering. Both a conventional type I proportional-integral (PI) controller and a fuzzy logic controller (FLC) are considered. The PI controller is designed using standard techniques and the two-level FLC / PI controller adjusts both proportional and integral feedback control gains around the baseline values based on heuristics and the current conditions as measured by the lateral error. Time-based simulations using MATLAB / SIMULINK permit a comparison between both controllers for several different simulation scenarios of interest. Primary performance metrics considered were percent overshoot and settling time in response to a step input. In general...