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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

Návrh části pohonu elektromobilu pro smíšený provoz / Design of part electric vehicle driving unit for mixed traffic

Matela, Petr January 2013 (has links)
Main goal of this master thesis is designing of a part of electric vehicle driving unit for mixed traffic. The drive purpose is to replace main drive of a utility van. First part of the thesis contains description of methodology used for energy consumption evaluation. In the next part there is description of current electric drive used in the van, design of a new one, best variant selection to suit company needs, energy consumption calculation, design and realization of the drive holder and final comparison of current and new drive design.
112

Neighbourhood effects and the adoption of new vehicle technologies : exploring consumer take-up of Toyota Priuses

Pridmore, Alison January 2016 (has links)
Innovative passenger vehicle technologies are required to make significant contributions to climate change mitigation. A number of challenges exist as barriers to their adoption. One key opportunity is the potential for social influence to have a positive impact on adoption rates. Social influence is how an individual's decisions can be influenced by other people – what their peers and others say and do and how this, in turn, affects the diffusion of new behaviours. The mixed method research detailed in this thesis contributes to an emerging interest in social influence in transport studies addressing a key research gap, the spatial aspects of this influence. Spatial analysis of private Toyota Prius vehicle ownership, was undertaken at the Output Area level for London for the period 2000 to 2011. Exploratory Spatial Data Analysis (ESDA), an important first step in spatial analysis, indicated the presence of spatial autocorrelation and Toyota Prius spatial clusters ('hotspots'). These 'hotspots' enlarged over time which can be indicative of social influence. This informed the need for in-depth quantitative analysis on the role of co-variables through the use of a Zero Inflated Negative Binomial model and the choice of case study areas for qualitative interviews. In the model, 'what your neighbours do' is a key co-variable represented by the average number of Priuses from neighbouring Output Areas (OA). This measure of social influence had a positive impact on the number of Toyota Priuses in a neighbourhood. The likelihood of Prius ownership in an OA increases by over 50% when the average number of Priuses in neighbouring OA increases by one. The case study OAs were examined in detail setting the scene for the qualitative interviews. Nine face-to-face semi-structured interviews were undertaken with current and potential future Toyota Prius owners. All referenced at least one form of social influence. The influences included direct observation of the vehicles, the opportunity to trial vehicles and changes in the symbolism of the vehicle through its adoption by others. Broader findings were consistent with the literature, for example with regard to the role of congestion charge exemptions and the socio-economic background of the participants. The confirmation of social influence indicated by these findings could assist in the geographic positioning of demonstration schemes or in the allocation of grants, with the economic assessment benefits of grant programmes, because of the 'knock-on' effects of social influence, potentially being wider than conventionally assumed.
113

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

Marisa Aparecida Amaro Malvestio 15 December 2005 (has links)
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, considerando os intervalos até 6h,12h, 24h, 48h, até 7 dias e até o término da internação. Os homens (86,9%) e a faixa etária de 20 a 29 anos (36,0%) foram as mais freqüentes. Os atropelamentos (45,1%) e o envolvimento de motocicletas e seus ocupantes (30,9%) foram os destaques dentre os mecanismos de trauma. A média do RTS na cena e do ISS, foram respectivamente 8,8 e 19,4.Os segmentos corpóreos mais atingidos foram: cabeça (58,8%), membros inferiores (45,1%) e superfície externa (40%). A média de tempo consumido na fase de APH foi 41min (tempo de cena 20,2min). Ocorreram 36% de óbitos, (metade em até 6 horas). A análise estatística revelou 24 fatores associados à sobrevivência, dentre eles, os procedimentos respiratórios avançados e os circulatórios básicos, as variáveis relativas ao RTS e a gravidade (ISS, MAIS e o número de lesões). No modelo final de Cox, ter sido submetido a procedimentos respiratórios avançados, compressões torácicas, apresentar lesão abdominal e ISS>25, foi associado a maior risco para o óbito até 48h após o trauma. Até 7 dias, a compressão torácica não se manteve no modelo final e a PAS de zero a 75mmHg apresentou associação com a morte após o acidente. Até a alta hospitalar, a ausência de PAS na avaliação inicial permaneceu no modelo. A reposição de volume foi o único fator com valor protetor para o risco de óbito presente em todos os momentos / The prehospital care (PH) is an important resource to trauma victims’ care. Nevertheless, there is great difficulty in demonstrating the PH intervention’s positive effect in victim’s survival, especially when concerning the advanced life support (ALS). The aim of this study is to characterize motor vehicle crash victims with Revised Trauma Score (RTS) <11 cared by municipal ALS and moved to tertiary hospitals in São Paulo in addition to identifying the prehospital variables associated to survival, and to evaluate their values as victim survival outcome determinant. The variables evaluated were: sex, age, trauma mechanism, basic life support and ALS procedures, physiological measures in the accident scene (considering the RTS, its parameters and fluctuations), the time consumed in PH phase, trauma severity by Injury Severity Score (ISS), the Maximum Abbreviated Injury Scale (MAIS) and number of lesions in each body region. The main results obtained by 175 victims between 12 e 65 years of age were submitted to the Kaplan Meier Survival Analysis and to Cox Proportional hazards Regression Analysis. The dependent variable was the survival time after the motor vehicle accident considering the intervals up to 6,12,24 and 48hs , up to 7 days and until the time of hospital discharge. Men (86,9%) and the 20 to 29 aged group (36%) were the most frequent. The pedestrians struck by car (45,1%) and the motorcycles (and their riders) (30,9%)were the highlight in trauma mechanisms. The RTS and the ISS average were 8,8 and 19,4 respectively. The more damaged body regions were head (58,8%), lower limbs (45,1%) and external surface (40%).The prehospital time average was 41 min (scene time 20,2min).Death rate was 36% (half of which up to 6hs).The statistical analysis revealed 24 survival associated factors. The ALS and the circulatory basic procedures, the RTS variables and the trauma severity (ISS,MAIS and number of lesions) were within them. In the final Cox Model were associated to higher risk of death up to 48hs after trauma: the submission to ALS respiratory procedures, chest compressions, the presence of abdominal injuries and ISS>25 .Until the 7th day the chest compression was not sustained in a final model and the systolic blood pressure (SBP) from zero to 75mmHg revealed statistical association with death after trauma. Until hospital discharge the SBP absence in scene evaluation remained in the model. The prehospital intravenous fluid refilling was the only factor of protector value to death risk in all moments
114

Avaliação de cenários para substituição de uma frota veicular na administração pública baseada na determinação da vida útil econômica

Mezzari, Vinicius Troian 10 July 2017 (has links)
A Constituição Federal de 1988, a carta magna do Brasil, foi responsável por estabelecer meios para a modernização na condução da administração pública brasileira. O modelo de administração gerencial, proposto na década subsequente, ampliou o entendimento de que o Estado precisa assemelhar-se cada vez mais à iniciativa privada e tratar as necessidades dos contribuintes como uma empresa trata seus clientes. Este trabalho visa avaliar cenários para substituição de frota na Prefeitura Municipal de Caxias do Sul, avaliando os diferentes custos e critérios para tomada de decisões relativas à substituição. Um método formal é aplicado para calcular a vida útil econômica da frota em análise, baseado em princípios de Engenharia Econômica, aproximando as características de tomada de decisão da administração pública às práticas da iniciativa privada. Diferentes cenários foram simulados que otimizaram a aplicação dos recursos públicos, resultando em melhor aplicação dos recursos públicos. Os resultados das simulações e cenários apontam que se possibilite atingir uma economia de recursos financeiros que podem variar desde 12% e chegar até 41,31%. / Submitted by Ana Guimarães Pereira (agpereir@ucs.br) on 2017-08-15T14:30:23Z No. of bitstreams: 1 Dissertacao Vinicius Troian Mezzari.pdf: 2965752 bytes, checksum: 10d64cc6df554f5e68ae0d41993f7416 (MD5) / Made available in DSpace on 2017-08-15T14:30:23Z (GMT). No. of bitstreams: 1 Dissertacao Vinicius Troian Mezzari.pdf: 2965752 bytes, checksum: 10d64cc6df554f5e68ae0d41993f7416 (MD5) Previous issue date: 2017-08-15 / Brazilian Federal Constitution, created in 1988, was responsible for establishing ways to modernize brazilian public administration practices. The management administration model, proposed in the next decade, expanded the understanding that the State should act even more like private companies and deal with tax payers needs the same way a private company deal with customers. This work aims to analyze different scenarios fleet substitution method applied in Caxias do Sul city hall, evaluating the costs relative to fleet and the actual decision taking criteria, regarding fleet substitution. Subsequently, it applies a formal method to calculate the fleet economic life, based on Economic Engineering principles, turning public administration decision making characteristics closer to the private companies’ administration practices, simulating different scenarios, improving public resources application, resulting in better use of the values taken under taxes. Simulations and scenarios results show that it is possible to achieve costs reductions that start from 12% and goes up to 41.31%.
115

Projeto e desenvolvimento de um sistema de controle para permitir a dirigibilidade de um veículo por meio do acionamento de um joystick. / Project and development of a control system to allow the handling of a vehicle by pushing a joystick.

Arthur Vieira Netto Junior 06 July 2012 (has links)
Este trabalho visa o desenvolvimento de um sistema de controle, para permitir a dirigibilidade de um veículo automotor, por meio do acionamento de um joystick por um usuário, que substitui o volante e os pedais do acelerador e do freio. Foi construída uma placa de controle, que recebe os sinais de controle tais como esterçamento, aceleração e frenagem vindos do joystick operado pelo usuário, processa esses sinais e aciona eletronicamente os atuadores mecânicos no volante da direção, no servo freio e no acelerador, permitindo o controle dinâmico do veículo. Para testar esse sistema de controle foi desenvolvido um simulador de dinâmica veicular, que fornece em tempo real, as respostas dinâmicas de um veículo quando solicitado pelo usuário, por meio de comandos de direção, aceleração e frenagem. Associada ao referido simulador foi desenvolvida uma bancada de testes, que inclui os atuadores mecânicos, sensores, placa de controle e o joystick, que são testados em tempo real por um usuário, dirigindo um veículo com o auxílio do simulador em uma estrada virtual, realizando manobras como curvas, acelerações e frenagens variadas. Durante os testes mencionados foi encontrada uma série de falhas, que comprometiam a segurança e a dirigibilidade do veículo. Com base nessas falhas foi construída uma árvore de falhas, para o sistema proposto, cuja falha principal era a perda da dirigibilidade do veículo. Partindo da análise qualitativa da árvore de falhas foi proposta uma série de ações corretivas, visando manter o sistema no âmbito da dirigibilidade segura, para o usuário. Finalmente, uma proposta de um protocolo de segurança, para desenvolvimento de sistemas drive-by-wire é sugerida tendo como base o desenvolvimento deste trabalho. / This work aims the development of a control system, to allow the handling of a automotive vehicle, by moving a joystick, which replaces the steering wheel, accelerator and braking pedals and is operated by a user. An electronic control board was built to receive control signals, such as steering, acceleration and braking signals, using a joystick handled by a user. It converts those signals and activates the mechanical actuators in the steering wheel, brake booster and accelerator, to allow the dynamic control of the vehicle. To test that control system, it was developed a vehicle dynamics simulator, which provides, in real time, the dynamics responses of a vehicle when driven by a user, by steering, braking and accelerating commands. Together with the simulator it was developed a test bench, with mechanical actuators, sensors, a control board and a joystick, which were tested in real time, by a user driving a vehicle with the assistance of the simulator, on a virtual road, performing maneuvers like curves, accelerations and varied braking. During the test it was found a series of faults, which affected the safety and driveability of the vehicle. Based on these faults, it was built a fault tree, to the proposed system, whose main fault was the loss of driveability of the vehicle. Based on the qualitative analysis of the fault tree, it was proposed a series of corrective actions, in order to keep the system on scope of the safe driveability. Finally, a proposal for a safety protocol for drive-by-wire systems was made, based on the development of this work.
116

Avaliação de cenários para substituição de uma frota veicular na administração pública baseada na determinação da vida útil econômica

Mezzari, Vinicius Troian 10 July 2017 (has links)
A Constituição Federal de 1988, a carta magna do Brasil, foi responsável por estabelecer meios para a modernização na condução da administração pública brasileira. O modelo de administração gerencial, proposto na década subsequente, ampliou o entendimento de que o Estado precisa assemelhar-se cada vez mais à iniciativa privada e tratar as necessidades dos contribuintes como uma empresa trata seus clientes. Este trabalho visa avaliar cenários para substituição de frota na Prefeitura Municipal de Caxias do Sul, avaliando os diferentes custos e critérios para tomada de decisões relativas à substituição. Um método formal é aplicado para calcular a vida útil econômica da frota em análise, baseado em princípios de Engenharia Econômica, aproximando as características de tomada de decisão da administração pública às práticas da iniciativa privada. Diferentes cenários foram simulados que otimizaram a aplicação dos recursos públicos, resultando em melhor aplicação dos recursos públicos. Os resultados das simulações e cenários apontam que se possibilite atingir uma economia de recursos financeiros que podem variar desde 12% e chegar até 41,31%. / Brazilian Federal Constitution, created in 1988, was responsible for establishing ways to modernize brazilian public administration practices. The management administration model, proposed in the next decade, expanded the understanding that the State should act even more like private companies and deal with tax payers needs the same way a private company deal with customers. This work aims to analyze different scenarios fleet substitution method applied in Caxias do Sul city hall, evaluating the costs relative to fleet and the actual decision taking criteria, regarding fleet substitution. Subsequently, it applies a formal method to calculate the fleet economic life, based on Economic Engineering principles, turning public administration decision making characteristics closer to the private companies’ administration practices, simulating different scenarios, improving public resources application, resulting in better use of the values taken under taxes. Simulations and scenarios results show that it is possible to achieve costs reductions that start from 12% and goes up to 41.31%.
117

A critical investigation of plant optimization, to improve the production process of Mercedes-Benz commercial vehicles in South Africa. (Jan 2004 - Sept 2004)

Naidoo, Desalin Rajoo January 2005 (has links)
The research thesis reflects a positive improvement to the plant efficiency through strategic optimisation planning and controlling systems. It’s important to note that the set goals of the research were achieved, with total employee buy-in contributing to the success and sustainability of these improvements. Purposive sample methods allowed for the twenty employees from a total of 172, to be interviewed for both the pre and post testing. The paradigm of the research contributed to integrative communication between brainstorming and action. The efforts of the total workforce must be commended, for strategically aligning the organizational goals and objectives to realization. The content of the thesis, show a direct relationship between the plant optimisation and the increase in the production volumes. The understanding of the downtime reports for the period specified is a direct reflection to the improvement in quality, and the reduction of the overall poor workmanship graphs indicates positively to the reduction in cost. The last value driver, on-time delivery shows a vast improvement in maintaining the customer satisfaction, when considering the increase to the production volume capacity. These improvements have made further volume increases probable, and the understanding of Ikhwezi Trucktech management to negotiate with realized information for future capacity planning.
118

An analysis of strategies used to manage conflict at Volkswagen of South Africa

Conybeare, Gaily January 2008 (has links)
This research study addresses the problem of determining the strategies that can be used by Internal Audit at Volkswagen of South Africa to manage conflict effectively. To achieve this objective a comprehensive literature study was performed to determine the views on conflict and evaluate the various conflict models. The study also included the reasons for and sources of conflict and the effects of conflict on the performance and controls within VWSA. The identification of conflict management strategies and subsequent conflict management styles were revealed by the literature study. Various discussions from different authors on how to resolve conflict situations are also discussed. The literature review serves as a model in the development of a guideline for VWSA Internal Audit team and management to manage conflict. Senior Management, middle management and staff from various departments within VWSA were requested to complete a questionnaire in order to determine the strategies and effectiveness of these strategies used by Internal Audit to manage conflict. The questionnaire was developed in accordance with the findings from the research. A pilot study was conducted to evaluate the relevance of the study to the problem questions and to evaluate whether the questionnaire will be easily understood. The answers of the respondents were analyzed and compared to the findings of the literature study. The information obtained from the literature study and from the respondents resulted in various recommendations and conclusions.
119

An assessment of the supplier development practices at Volkswagen of South Africa

Erasmus, Bradley Quentin January 2006 (has links)
The underlying objective of the research is to assess the nature of the supplier training at Volkswagen of South Africa (VWSA). To achieve this objective, a theoretical study was conducted to establish what literature reveals to be the most important theory of supply chain management as well as supplier development geared towards lean manufacturing. The information obtained in the literature study was analysed to solve the main problem namely, an assessment of the nature of the supplier training at Volkswagen of South Africa (VWSA). The research was divided into two questionnaires: The first questionnaire is targeted at the suppliers. This questionnaire has two sections namely section A, the biographical data and section B attempts to determine the quality systems and manufacturing requirements. It further attempts to gauge training support and needs as compared to other OEM’s. The second questionnaire is targeted at the Supplier Development Manager. The aim of this questionnaire is to establish what the current training offerings are, the source of what VWSA teachers and the awareness of the Toyota Training College.
120

Understanding the Challenges of the Older Driver: Attention, Road Complexity and Assessment

Stinchcombe, Arne January 2011 (has links)
Older adults are at an increased risk for motor-vehicle collisions (MVCs) once distance driven is considered, a finding that is partly attributed to a decline in attention related processes associated with age. MVCs typically occur in highly specific areas, suggesting a role of the complexity of the driving environment contributing to the occurrence of MVCs. The goal of this thesis was to explore the attentional demands of simulated driving events of varying complexity among young, mature and older drivers. In the present studies, attentional demand associated with driving was assessed through the peripheral detection task (PDT), a method in which a stimulus unrelated to the driving task is presented and drivers manually respond immediately upon its detection; latency to respond is recorded. The complexity of the driving environment was operationalized in terms of vehicle handling and of information processing elements. In the first study, inexperienced drivers completed a series simulated driving scenarios that varied according to their information processing and vehicle handling demands. The results showed a reduction in PDT performance at intersections where information processing is increased as well as when handling maneuvers behind a lead vehicle were required. Building on these findings, the second study employed the identical protocol as the first but examined differences in attentional demand between mid-aged and older drivers. The results indicated that when information processing demands were increased through the addition of traffic, and buildings, all participants exhibited greater workload regardless of age. The third study presented young, mid-aged, and older drivers with a simulated driving assessment course and administered several cognitive tasks. The results of the third study supported the hypothesis in that complex driving situations elicited greater attentional demand among drivers of all ages. Older adults showed greater attentional demand in comparison to young and mid-aged adults even after controlling for baseline response time. Older drivers also scored poorer on a global measure of driving safety. The results of this thesis highlight the roles of intrinsic and extrinsic factors involved in safe driving and are discussed in terms of appropriate interventions to improve road safety.

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