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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.
161

A cidade e a mobilidade na era do automóvel: a obra de Colin Buchanan (1958-1966) / The city and mobility in the automobile age: the work of Colin Buchanan (1958-1966)

Seixas, Alexandre Rodrigues 26 August 2010 (has links)
Esta tese busca dar subsídios à compreensão da complexa relação entre cidade e seus sistemas de circulação, sobretudo a partir das diversas transformações urbanas ocorridas ao longo do século XX. É nossa hipótese que a obra do engenheiro-urbanista britânico Colin Buchanan, elaborada entre 1958 e 1966, constitui-se em um momento importante do debate acerca desta relação, sobretudo pelo deslocamento da ênfase das preocupações com a dinâmica da circulação urbana para questões relacionadas à cidade. Neste movimento, Buchanan estabelece um forte posicionamento contra algumas correntes hegemônicas de planejamento de transportes que enfatizavam as questões construtivas ou privilegiavam análises de base econômica. Seu trabalho identifica uma clara opção pelo automóvel como modo de transporte e discute quatro questões urbanas fundamentais: 1) a mobilidade urbana como uma questão política; 2) a circulação urbana como fenômeno; 3) a escala urbana local; 4) a estrutura urbana e regional para o tráfego. Estas quatro dimensões, como foram denominadas neste trabalho, ancoram aquilo que consideramos a sua proposta de cidade para a era do automóvel. / The object of this thesis is to provide subsidies for understanding the complex relationship between the city and its circulation systems, especially from the several urban transformations that have occurred over the twentieth century. It is our hypothesis that the work of the British engineer-planner Colin Buchanan, drafted between 1958 and 1966, constitutes an important contribution to the debate about this relationship, mainly by shifting the focus of concerns about traffic issues for the city. In this movement, Buchanan makes a strong point of view against some hegemonic currents of transportation planning that emphasized the issues favored constructive or economic analysis. This work identifies a clear option for the car as a mode of transportation and discusses four key urban issues: 1) urban mobility as a political issue, 2) the movement as urban phenomenon, 3) the local urban scale, 4) urban structure and regional traffic. These four dimensions, as named in this work, support what we consider his proposal to the city for the automobile age.
162

Transportation engineering assimilated livability planning using micro-simulation models for Southeast Florida

Unknown Date (has links)
Transportation engineering has taken upon a new role; to empower the alternative modes of travel: walking, biking, and bus transit. In this new era, engineers are rethinking a network designed predominately for the automobile. The ultimate goal of this research is to create a process that can make a vehicle dominant corridor a desirable, livable thoroughfare by livability design and context sensitive performance measures. Balancing travel modes requires an account of vehicular traffic and the impact of reconfiguring existing conditions. The analysis herein is conducted by field data collection, transportation equations and microsimulation. Simulating traffic behavior will be the means to apply livable alternatives comparable to existing Southeast Florida conditions. The results herein have shown that micro-simulation can be utilized in transportation planning to reveal good livability alternatives. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2015 / FAU Electronic Theses and Dissertations Collection
163

Hybrid model for optimization of cost operations for a university transit service

Unknown Date (has links)
The demand on transportation infrastructure is dramatically increasing due to population growth causing the transportation systems to be pushed to their limits. With the projected population growth, not only for the U.S. but especially for the higher education field, university campuses are of great importance for transportation engineers. Urban univeristy campuses are considered major trip generators and with the population forecast many challenges are bound to arise. The implementation of an improved transit system provides a lower-cost solution to the continuously increasing congestion problems in university campus road networks and surrounding areas. This paper presents a methodology focused on the development of a hybrid system concentrated in three main aspects of transit functionality : access to bus stop location, reasonable travel time and low cost. Two methods for bus stop locations assessment are presented for two levels of analysis : microscopic and mesoscopic. The resulting travel time from the improved bus stop locations is analyzed and compared to the initial conditions by using a microsimulation platform. The development of a mathematical model targets the overall system's cost minimization, including user and operator cost, while maximizing the service coverage. The results demonstrate the benefits of the bus stop assessment by the two applied methods, as well as, the benefits of the route and headway selection based on the mathematical model. Moreover, the results indicate that the generation of routes using travel time as the impedance factor generates the optimal possible routes to obtain the minimum system's overall cost. / by Alicia Benazir Portal Palomo. / Thesis (M.S.C.S.)--Florida Atlantic University, 2012. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2012. Mode of access: World Wide Web.
164

Optimization of bus system characteristics in urban areas under normal and emergency conditions

Unknown Date (has links)
Catastrophic events in the past revealed the need for more research in the field of emergency evacuation. During such a procedure, different problems such as congestion at the related traffic networks because of the large number of the evacuating vehicles can occur. Current best practices, in order to deal with such problems, suggest the further involvement of buses in evacuation operations. On the first part of this study after the accurate development of the related simulation model, the optimization of a selected bus system characteristics focusing on the vehicle routing parameter will follow through the development and the application of a non-linear cost minimization problem. On the second part, the potential use of the regular-everyday bus routes in a no-notice emergency evacuation in order to save time comparing to the time needed so as to assign the actual evacuation routes to the evacuation bus vehicles will be analyzed. / by Ioannis Psarros. / Thesis (M.S.C.S.)--Florida Atlantic University, 2012. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2012. Mode of access: World Wide Web.
165

A multi-criteria framework for appraisal of rural roads in developing countries.

Chew, Keat Soon January 1978 (has links)
Thesis. 1978. M.S.--Massachusetts Institute of Technology. Dept. of Civil Engineering. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Bibliography: leaves 131-134. / M.S.
166

Análise do processo de planejamento dos transportes como contribuição para a mobilidade urbana sustentável / Analysis of the transportation planning process as a contribution to a sustainable urban mobility

Azevedo Filho, Mário Angelo Nunes de 02 October 2012 (has links)
Esta pesquisa tratou de uma avaliação do processo de planejamento de transportes urbanos e suas implicações para o funcionamento das cidades. Foi feita inicialmente uma revisão dos métodos mais consagrados de planejamento, aqui chamados de tradicionais, contrastando- os com abordagens alternativas que visam a mobilidade urbana sustentável. Alguns planos de transportes e de mobilidade, principalmente referentes a casos brasileiros, foram analisados e, a partir daí, foi selecionada para estudo de caso a Região Metropolitana de Belém - RMB. Para esta região foram desenvolvidos nove estudos de transportes no período de 1978 a 2010. Nas propostas destes estudos percebe - se, de maneira geral, um viés de favorecimento dos modos motorizados de transportes. Mesmo com o grande número de estudos, no entanto, a mobilidade urbana em Belém não chegou a ser considerada como boa durante a investigação. Isso foi verificado com o cálculo do Índice de Mobilidade Urbana Sustentável para diferentes cenários, centrados nos anos de 1980, 1991, 2001 e 2011. Outro experimento envolveu a avaliação dos possíveis impactos das medidas propostas nos estudos caso fossem implantadas. Os estudos melhor avaliados foram os Planos Diretores de Transportes Urbanos concluídos em 1991 e 2001. Embora a preocupação com os impactos ambientais causados pelo sistema de transportes esteja presente em todos os estudos, as propostas não contemplaram bem esta questão. O discurso de melhoria do meio ambiente começou de maneira mais moderada nos primeiros planos e foi ganhando mais força ao longo do tempo, até mesmo pelas exigências, cada vez maiores, da legislação nacional e local. Apesar disso, no conjunto dos planos, o Domínio \"Aspectos Ambientais\" foi, comparativamente, o menos importante. A ideia de que, na medida em que as pessoas melhoram de condição econômica elas deixam de utilizar o transporte público e passam para o automóvel, parece levar a um problema sem solução. Não são consideradas medidas que restrinjam o uso do automóvel, o que poderia levar a melhores soluções. Outros fatores que impedem a implantação de um sistema de transportes mais adequado é a inexistência de uma estrutura de gerência metropolitana e os entraves para alterar o arranjo atual das empresas de transporte coletivo e suas áreas exclusivas de operação. Embora não tenha aqui sido feita uma avaliação detalhada de outros casos, as práticas observadas no caso de Belém são seguramente muito próximas daquilo que ocorre em outras cidades e regiões metropolitanas brasileiras. Por outro lado, a entrada em vigor em 2012 da lei que estabelece as diretrizes para a Política Nacional de Mobilidade Urbana abre perspectivas para uma mudança nos procedimentos de planejamento visando à mobilidade urbana sustentável. / The research dealt with the process of urban transportation planning and its consequences on the cities\' functioning. It started with a literature review, which was carried out for comparing the well established planning methods, here named as traditional, with the ones that propose an alternative approach aiming at a sustainable urban mobility. Some transportation or mobility plans, mainly from Brazilian cities, were thoroughly examined thereafter. Their inspection led to the selection of the RMB (which is the abbreviation of Belém Metropolitan Area, in Portuguese), as a case study. From 1978 to 2010, nine transportation studies or plans had been produced for that region. In general, most proposals found in these studies are biased towards motorized transport modes. Despite all these studies, however, the mobility of Belém was never classified as good along the investigation. This was assessed with the estimation of a Index of Sustainable Urban Mobility - I_SUM for different scenarios in the years 1980, 1991, 2001 and 2010. Another experiment consisted of an evaluation of the potential impact of the solutions proposed in the reports. As a result, the better ranked studies were the Urban Transportation Master Plans developed in 1991 and 2001. Also, although a concern about the environmental impacts of the transportation system had been found in all studies, this question was far from being solved. The arguments in favor of environmental improvements started with moderate emphasis in the first plans and grew stronger toward the recent plans, in part due to local and national legislation. Nevertheless, the set of plans performed poorly in the Environmental Aspects Domain. The idea that improvements on people financial condition leads to a modal shift from transit to cars seems to produce an unsolvable problem. Restrictions on motoring would possibly open space for better solutions, but they were never effectively consid ered in the analyzed plans. In the case considered, the lack of a metropolitan organization for the mobility management and the present setting of bus companies exclusive operational areas also make difficult the implementation of better transportation system. Even though detailed analyses were not conducted here for other cases, the practice observed in Belém is surely quite similar to what is found in other Brazilian cities and metropolitan areas. In contrast, the fact that a federal law establishing the guidelines for a National Policy for Urban Mobility was recently passed, opens prospects of changes on planning procedures aiming at a sustainable urban mobility.
167

Modelagem da geração e distribuição de viagens para escolas utilizando cellular automata e avaliação multicritério / Generation and distribution models of school trips using cellular automata and multicriteria evaluation

Vanessa da Silva Santos 27 September 2005 (has links)
Em condições acentuadas de restrições de recursos para a construção e manutenção de infra-estruturas urbanas, torna-se importante caracterizar e localizar espacialmente sua demanda para auxiliar os planejadores no processo decisório que envolve sua implementação, ampliação e manutenção, de forma que os usuários sejam atendidos da melhor maneira possível e dentro das possibilidades financeiras das prefeituras. Este foi o ponto de partida para este trabalho, cujos objetivos são modelar a dinâmica populacional intra-urbana de uma cidade de médio porte brasileira através da combinação de modelos com cellular automata e avaliação multicritério e, a partir daí, a distribuição de viagens para uma infra-estrutura pontual específica, as Escolas Municipais de Educação Infantil (EMEIs). Na aplicação prática da pesquisa inicialmente modela-se a dinâmica populacional intra-urbana na cidade de São Carlos como um todo com um modelo de cellular automata e um modelo demográfico de extrapolação de tendências. Baseando-se em valores de densidade populacional obtidos com dados dos censos do IBGE referentes aos anos de 1980, 1991 e 2000, obteve-se o cenário referente ao ano de 2010. O modelo urbano de cellular automata utilizado foi construído em três fases: quantificação da dispersão (cálculo da área total que deveria ser incorporada à mancha urbana), localização da dispersão (definição da localização das áreas que deveriam ser incorporadas à mancha urbana) e diferenciação da dispersão (cálculo das densidades demográficas na mancha urbana prevista). O modelo conseguiu apresentar bons resultados tanto na localização quanto na diferenciação da dispersão. Para caracterizar a demanda por EMEIs neste caso estabeleceu-se uma relação matemática entre a população total e a população na faixa etária que utiliza o serviço das EMEIs (4 a 6 anos). No caso do modelo demográfico, no qual a densidade populacional foi calculada a partir de uma curva de tendência linear, notou-se que devido à restrição da mancha urbana à área previamente ocupada, surgem valores de densidade populacional acima da faixa observada na série histórica. A demanda por EMEIs neste modelo também foi obtida através de uma curva de tendência linear, utilizando dados específicos da faixa etária de 4 a 6 anos. Após a caracterização da demanda por EMEIs foram criados cenários de distribuição de viagens para as mesmas nos anos de 2000 e 2010. Observou-se que os modelos apresentaram comportamentos distintos na caracterização da demanda, que foi expressivamente maior no modelo de cellular automata mas quando tiveram a demanda adaptada à oferta existente, através da multiplicação por uma taxa de atendimento, apresentaram resultados bastante semelhantes. No entanto, considerando um cenário muito provável de aumento da oferta, seja em escolas novas ou nas já existentes, o impacto sobre os transportes seria muito melhor caracterizado no caso dos modelos de CA, não só porque as estimativas de demanda foram significativamente maiores, mas também porque incorporaram a possibilidade de ocupação de novas áreas urbanas / In conditions of extreme restrictions of resources for construction and maintainance of public facilities, the correct demand alocation is essential not only for the decision-making process, which involves their implementation and rational use, but also for reaching a significant share of the demand with a reasonable level of service and within the budget limits. That was the starting point for the definition of the objectives of this work, which are to model the population dynamics in a medium-sized city by using a cellular automata approach and multicriteria evaluation techniques and to simulate trip distribution patterns to a particular public facility, the EMEIs, i.e., schools for children between 4 and 6 years-old. The study starts with an application of two urban dynamics models in the city of São Carlos: a cellular automata model and a demographic model based on linear regression. A scenario of the year 2010 was built based on 1980, 1991, and 2000 census data. The cellular automata model was constructed in three fases: quantification of sprawl (definition of the total area added to the existing urban area), location of sprawl (alocation of areas of expansion), and differentiation of sprawl (definition of the population density in each cell of the new urban area). The model captured reasonably well the urban dynamics process in both location and differentiation of sprawl. The demand for EMEIs was then defined through the definition of a mathematical relationship between the total population and the target population. The population density predicted by the demographic model was calculated through a linear trend applied to historical data. It was significant in this case the occurrence of estimated values higher than the actual values mainly due to the restrictions of the urban area to its previous boundaries. The demand for EMEIs was also obtained using a linear trend, this time using specific data of the target population. Scenarios of trip distribution in the years 2000 and 2010 were created after the demand was modeled. The predictions of the models were very different, and the total demand estimation of the cellular automata model was higher than that obtained with the demographic model. When adjusting the demand to the existing supply in the year 2000, the trip distribution results were quite similar, although resulting in extremely different service rates. However, in a very likely scenario of supply growth, either through new or existing schools, the impacts on transportation would be better identified in the case of CA models, not only because they have produced higher demand estimates, but also because they have considered the inclusion of new areas into the modeled space
168

Relationships between economies of scale and the shape of transportation networks.

Gordon, Steven Ronald January 1975 (has links)
Thesis. 1975. Ph.D.--Massachusetts Institute of Technology. Dept. of Civil Engineering. / Bibliography: leaves 221-224. / Ph.D.
169

Transportation networks equilibration with discrete choice models.

Sheffi, Yosef, 1948- January 1978 (has links)
Thesis. 1978. Ph.D.--Massachusetts Institute of Technology. Dept. of Civil Engineering. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Bibliography: p. 119-124. / Ph.D.
170

An interorganizational analysis of urban transportation project development in Cairo, Egypt.

Michael, Martin Frank January 1978 (has links)
Thesis. 1978. M.C.P.--Massachusetts Institute of Technology. Dept. of Urban Studies and Planning. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ROTCH. / Bibliography: leaves 88-91. / M.C.P.

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