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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.
51

Análise de ferramentas computacionais para planejamento estratégico do uso do solo e transportes / Analysis of computer tools for strategic land use-transport planning

Gustavo Rennó Rocha 14 October 2010 (has links)
A constante ausência de planejamento urbano nos países em desenvolvimento é um dos principais fatores responsáveis pela ineficiência da infraestrutura pública de suas cidades, o que é agravado pelo fato de que muitas dessas cidades permanecem em processo de crescimento. Essa falta de planejamento gera inúmeros problemas, principalmente com relação à mobilidade e ao transporte, que por sua vez desencadeiam uma série de outros problemas. Dentre as principais limitações do planejamento sob tais condições, destaca-se a falta de ferramentas apropriadas. Propõe-se assim a caracterização de um modelo para o planejamento estratégico do uso do solo e transportes, com o qual é realizada uma aplicação na cidade de São Carlos, utilizando dados e ferramentas disponíveis. Dessa forma, são analisados os procedimentos executados tanto do ponto de vista técnico do planejamento, quanto do ponto de vista operacional das ferramentas e programas utilizados. Com isso, busca-se construir uma base referencial no sentido de auxiliar o uso, adaptação e desenvolvimento de ferramentas computacionais de planejamento urbano, principalmente para aplicações em cidades médias de países em desenvolvimento e com enfoque no transporte por ônibus. Baseando-se nas principais técnicas de planejamento compatíveis com essa abordagem, o modelo foi definido através de etapas sequenciais, desde a preparação dos dados reunidos, a projeção geográfica de futuros usos do solo, até a previsão e visualização da demanda por transporte urbano. Desse modo, utilizando apenas dados de fácil obtenção, como as informações do Plano Diretor, dados censitários e levantamentos de outras fontes confiáveis, é possível avaliar o impacto do crescimento urbano sobre o sistema de transportes. Para executar o modelo, fez-se uso dos programas What if? e TransCAD, trabalhando os dados através de seus Sistemas de Informações Geográficas e com o eventual auxílio de planilhas eletrônicas. Através da aplicação, o modelo produziu dois cenários distintos, representando diferentes padrões de ocupação e viagem, de acordo com as respectivas hipóteses consideradas. A grande diferença entre os resultados obtidos em cada cenário pode ser explicada principalmente pela falta de políticas de incentivo e controle da ocupação do solo. Entretanto, ambos os cenários apresentaram resultados semelhantes em alguns pontos da cidade, representando tendências bastante prováveis para os próximos anos. As ferramentas e procedimentos utilizados mostraram um bom desempenho do modelo, apesar de eventuais detalhes que podem ser aprimorados. / The absence of a regular urban planning practice in developing countries is one of the main causes of an inefficient use of the public infrastructures. That is aggravated by the fact that many cities of those countries are still growing. That lack of planning generates many mobility and transportation issues, which in turn result in many other problems. One of the constraints faced by planners to cope with that reality is the unavailability of suitable planning tools. As a consequence, a model for strategic land use-transport planning is proposed in this study. The model is then applied in the city of São Carlos, making use of available data and tools. The procedures applied are analyzed in two ways: from a planning standpoint and also regarding the operational performance of the planning tools and computer packages used. The purpose of the process was to build a reference framework for the use, adaptation and development of computer tools for urban planning, with a clear focus on medium-sized cities of developing countries that rely on buses for urban public transportation. The model was based on available and intensely used planning techniques compatible with the proposed approach. It was defined in sequential steps, from the data collection and treatment, the estimation and spatial distribution of projected urban land uses, to the evaluation and visualization of future urban transport demand. In such a way, it is possible to evaluate the impacts of urban growth on the transport system with data available in the city\'s Master Plan, census data files and other reliable sources. As the model was implemented in the computer programs What if? and TransCAD, the data used was treated in Geographic Information Systems and electronic spreadsheets. The model application produced two distinct scenarios, which represent different land use distributions and travel patterns resulting from the adopted hypotheses. The main difference found in the results obtained in the scenarios can be explained by the lack of policies for incentive and control of the urban land uses. However, both scenarios have shown similar results in specific points of the city, what suggests some likely trends for the near future. The tools and procedures used have indicated a good overall model performance, although there are details in which improvements can be done.
52

An initial implementation of a multi-agent transport simulator for South Africa

Fourie, P.J. (Pieter Jacobus) 24 June 2009 (has links)
Transport demand planning in South Africa is a neglected field of study, using obsolete methods to model an extremely complex, dynamic system composed of an eclectic mix of First and Third World transport technologies, infrastructure and economic participants. We identify agent-based simulation as a viable modelling paradigm capable of capturing the effects emerging from the complex interactions within the South African transport system, and proceed to implement the Multi-Agent Transport Simulation Toolkit (MATSim) for South Africa's economically important Gauteng province. This report describes the procedure followed to transform household travel survey, census and Geographic Information System (GIS) data into an activity-based transport demand description, executed on network graphs derived from GIS shape files. We investigate the influence of network resolution on solution quality and simulation time, by preparing a full network representation and a small version, containing no street-level links. Then we compare the accuracy of our data-derived transport demand with a lower bound solution. Finally the simulation is tested for repeatability and convergence. Comparisons of simulated versus actual traffic counts on important road network links during the morning and afternoon rush hour peaks show a minimum mean relative error of less than 40%. Using the same metric, the small network differs from the full representation by a maximum of 2% during the morning peak hour, but the full network requires three times as much memory to execute, and takes 5.2 times longer to perform a single iteration. Our census- and travel survey-derived demand performs significantly better than uniformly distributed random pairings of home- and work locations, which we took to be analogous to a lower bound solution. The smallest difference in corresponding mean relative error between the two cases comes to more than 50%. We introduce a new counts ratio error metric that removes the bias present in traditional counts comparison error metrics. The new metric shows that the spread (standard deviation) of counts comparison values for the random demand is twice to three times as large as that of our reference case. The simulation proves highly repeatable for different seed values of the pseudo-random number generator. An extended simulation run reveals that full systematic relaxation requires 400 iterations. Departure time histograms show how agents 'learn' to gradually load the network while still complying with activity constraints. The initial implementation has already sparked further research. Current priorities are improving activity assignment, incorporating commercial traffic and public transport, and the development and implementation of the minibus taxi para-transit mode. Copyright / Dissertation (MEng)--University of Pretoria, 2009. / Industrial and Systems Engineering / unrestricted
53

Heuristic Prioritization Of Emergency Evacuation Staging To Reduce Clearance Time

Mitchell, Steven 01 January 2006 (has links)
A region's evacuation strategy encompasses a variety of areas and needs. Primary among these is the minimization of total evacuation time, represented in models as the clearance time estimate (CTE). A generic testbed simulation network model was developed. An input/output (I/O) analysis was performed to establish a theoretical baseline CTE. Results were compared with simulations; analysis showed that the I/O method underestimated simulated CTE as a function of network size, with a correction factor range of 1.09 to 1.19. A regression model was developed for the generic network. Predictors were total trips, and network size defined as a function of origin-destination distance. Total Trips ranged between 40,000 and 60,000. Holding size constant, R-squared values ranged from 97.1 to 99.3, indicating a high goodness of fit. Holding Total Trips constant, R-squared values ranged from 74.5 to 89.2. Finally, both Total Trips and size were used as predictors; the resulting regression model had an R-squared value of 97.3. This overall model is more useful, since real world situations are not fixed in nature. The overall regression model was compared to a case network. The generic network regression model provided a close CTE approximation; deltas ranged from -4.7% to 8.6%. It was concluded that a generic network can serve as a surrogate for a case network over these ranges. This study developed and evaluated heuristic strategies for evacuation using the generic network. Strategies were compared with a simultaneous departure loading scenario. Six different grouping strategies were evaluated. An initial evaluation was conducted using the generic network, and strategies that showed potential CTE reduction were implemented on the case study network. Analysis indicated that the HF-10 (half-far) grouping for 60k total trips showed potential reduction. A complete simulation was conducted on the case network for all HF scenarios; an ANOVA was run using Dunnett's comparison. Results indicated that the HF grouping with 20% and 30% departure shifts showed potential for CTE reduction. From this it was concluded that the generic network could be used as a testbed for strategies that would show success on a case network.
54

Telecommuting Travel Behavior: Examining the Influence of Work Status on Distance and Mode Choice in the National Capital Region

Garden, Benjamin W.C. 10 1900 (has links)
<p>This study explores telecommuter travel behaviour by examining discretionary travel distance and mode choice. The study utilizes data obtained from the 2005 origin-destination survey conducted by TRANS, a joint transportation planning committee serving the National Capital Region of Canada. The study compares and explains the discretionary travel behavior of teleworkers relative to other population groups and identifies that the average teleworker travels 3 times farther than regular workers and 1.7 times farther than non-workers for discretionary purposes. Regression indicates that dependent children, vehicle accessibility, housing type, residential distance to the urban core, land-use mix, residence within a Greenbelt region and day of the week all positively affect travel distance. Conversely, age, proximity to shopping centers and inclement weather demonstrate significant negative effects. Then, through binary logistic regression, the study confirms that work status significantly influences mode choice. Similarly, the following predictor variables demonstrate a significant positive effect towards active mode choice: teleworker work status, larger household size, greater income, warmer temperature, closer proximity to shopping centers, apartment housing type, trips for recreational and restaurant purposes, taking subsequent trips in a day, and travel between 8:00 A.M. and 4:00 P.M. On the contrary, increased entropy, trips within the Greenbelt region, dependent children under 16 years old, increased vehicle accessibility and trips for transporting someone or for shopping purposes all reduce the probability of active travel mode choice.</p> / Master of Arts (MA)
55

Geração de viagens de passageiros urbanos: modelo individual com a inclusão da influência das características do domicílio / Urban passenger trip generation: individual model incorporating the influence of household characteristics

Tandel, Maria da Conceição Farias Freitas 18 August 1997 (has links)
Um dos enfoques mais utilizados na modelagem de geração de viagens de passageiros urbanos é a desagregação em nível de domicílios. Esta tese oferece razões lógicas e fortes evidências estatísticas para substituir modelos baseados em domicílios, introduzindo modelos desagregados em nível de indivíduos incorporando a influência das características e da estrutura do domicílio. Estes modelos provêm um considerável avanço sobre as práticas tradicionais. Um estudo de caso foi conduzido na região metropolitana de São Paulo - SP. Utilizou-se informação em nível individual, através de algumas variáveis disponíveis na pesquisa origem/destino de 1987 da Cia. do Metropolitano de São Paulo. Foi possível verificar várias vantagens em relação aos modelos tradicionais, bem como responder várias críticas aos modelos atuais. Analisou-se também os erros obtidos com o modelo individual com e sem a influência das características e estrutura domiciliares. / One approach that is widely used to conduct the urban passenger trip generation modelling is the disaggregate household based model. This thesis offers logical reasons and strong statistical evidences to replace household based models, indroducing individual disaggregate models, incorporating the influence of household characteristics and structure. These models represent a significant improvement over tradicional practice. A case study was conducted using data from metropolitan region of Sao Paulo City, Sao Paulo State. Information at individual levei was used, tluough some variables available in the Sao Paulo Metropolitan Company, 1987 origin/destination research. It was possible to verify several advantages in relation to traditional models as well as to answer several criticisms to the current models. It was also analysed errors obtained in the individual models with and without the influence of household characteristics and structure.
56

Geração de viagens de passageiros urbanos: modelo individual com a inclusão da influência das características do domicílio / Urban passenger trip generation: individual model incorporating the influence of household characteristics

Maria da Conceição Farias Freitas Tandel 18 August 1997 (has links)
Um dos enfoques mais utilizados na modelagem de geração de viagens de passageiros urbanos é a desagregação em nível de domicílios. Esta tese oferece razões lógicas e fortes evidências estatísticas para substituir modelos baseados em domicílios, introduzindo modelos desagregados em nível de indivíduos incorporando a influência das características e da estrutura do domicílio. Estes modelos provêm um considerável avanço sobre as práticas tradicionais. Um estudo de caso foi conduzido na região metropolitana de São Paulo - SP. Utilizou-se informação em nível individual, através de algumas variáveis disponíveis na pesquisa origem/destino de 1987 da Cia. do Metropolitano de São Paulo. Foi possível verificar várias vantagens em relação aos modelos tradicionais, bem como responder várias críticas aos modelos atuais. Analisou-se também os erros obtidos com o modelo individual com e sem a influência das características e estrutura domiciliares. / One approach that is widely used to conduct the urban passenger trip generation modelling is the disaggregate household based model. This thesis offers logical reasons and strong statistical evidences to replace household based models, indroducing individual disaggregate models, incorporating the influence of household characteristics and structure. These models represent a significant improvement over tradicional practice. A case study was conducted using data from metropolitan region of Sao Paulo City, Sao Paulo State. Information at individual levei was used, tluough some variables available in the Sao Paulo Metropolitan Company, 1987 origin/destination research. It was possible to verify several advantages in relation to traditional models as well as to answer several criticisms to the current models. It was also analysed errors obtained in the individual models with and without the influence of household characteristics and structure.
57

Contribuições ao estudo de implantação de pedágio urbano em São Paulo. / Contributions towards the study of congestion charging systems in São Paulo.

Dias, Felipe Ferreira 01 April 2015 (has links)
A Região Metropolitana de São Paulo (RMSP) sofre de sérios problemas de congestionamento, assim como muitas outras cidades de grande porte. Uma possível solução, proposta por pesquisadores de transportes, economia e ciências ambientais, é a implantação de um sistema de congestion charging, chamada no Brasil de pedágio urbano. Um dos objetivos do presente trabalho foi estabelecer os conceitos relacionados a este assunto e ilustrar as principais questões relacionadas à sua implantação. Espera-se que este trabalho possa auxiliar o desenvolvimento de estudos de avaliação da viabilidade e de impactos de sistemas propostos de congestion charging. Para atingir este objetivo, toca-se em diversos assuntos, como a definição de congestionamento e as formas de medi-lo, a base conceitual e teórica dos sistemas de congestion charging e seus diversos esquemas de diferenciação. São expostas também as medidas de mitigação de congestionamento que já foram implantadas na RMSP, quais foram os estudos já desenvolvidos considerando este tipo de política para a RMSP, e casos em que sistemas de congestion charging já foi implantado. Neste trabalho, desenvolveu-se também um modelo de escolha discreta a partir dos dados da Pesquisa Origem e Destino 2007 do METRÔ, onde pessoas deveriam escolher entre \"Transporte Coletivo\" e \"Transporte Público\". Este modelo foi utilizado para avaliar o potencial de impacto na divisão modal e de arrecadação de um congestion charge aplicado ao centro expandido de São Paulo. Adverte-se, porém, que os resultados obtidos são meramente ilustrativos. Mostra-se, também, que é possível avaliar a capacidade ociosa do sistema de transporte coletivo a partir dos dados disponíveis de bilhetagem e de GPS dos ônibus. Este processo é exemplificado através do cálculo de capacidade de uma única viagem de um único ônibus, dada a dificuldade de automatização deste processo para abranger toda a frota. / The São Paulo Metropolitan Region (SPMR) suffers from severe traffic congestion, as do many other large-scale urban areas around the world. A possible solution to this issue, which has been suggested by transportation, economics and environmental researchers, is the implementation of a congestion charging system. One of the objectives of this project is to establish clear concepts and shed light on the main issues regarding these systems by means of a comprehensive literary review. It is expected that this project may help the development of in-depth studies carried in order to evaluate the viability and impacts of congestion charging proposals. In order to achieve this goal, many subjects are addressed, such as the definition of congestion, how its measured, the theoretical backgrounds that support congestion charging schemes, their different degrees of differentiation, which policies were enacted in order to reduce traffic congestion in São Paulo, what considerations and studies have already been developed for Brazil and São Paulo regarding these systems and where have these systems been successfully installed. Later chapters deal with another goal of this project: estimating how a congestion charging system would affect SPMR. This was achieved through a multinomial logit model, where decision-makers choose between \"Public Transportation\" and \"Private Automobile\". The results presented at this phase are merely indicative of certain tendencies and should not be considered final. This project also attempts to show that given the available Automated Fare Collection (AFC) data and Automated Vehicle Location (AVL) data, it is possible to estimate the current public transportation system\'s unused capacity. The author shows this by calculating the capacity of one bus trip using these data, but also explains the difficulties of expanding this analysis to the whole of SPMR\'s public transportation system.
58

Utility-based approaches to understanding the effects of urban compactness on travel behavior: a case of Seoul, Korea

Gim, Tae-Hyoung 13 January 2014 (has links)
Automobile use is associated with significant problems such as air pollution and obesity. Decisions to use the automobile or its alternatives, including walk, bicycle, and public transit, are believed to be associated with urban form. However, in contrast to the hypothesis that compact urban form significantly reduces automobile travel, previous studies reported only a modest effect on travel behavior. These studies, largely built on microeconomic utility theory, are not sufficient for assessing the effect of compactness, for several reasons: (1) The studies postulate that travel invokes only disutility, but travel may also provide intrinsic utility or benefits insomuch as people travel for its own sake; (2) the studies have traditionally focused on how urban compactness reduces the distance between trip origin and destination and accordingly reduces trip time, but urban compactness also increases congestion and reduces trip speed, and thus increases trip time; and (3) the studies have mostly examined automobile commuting, but people travel for various purposes, using different travel modes, and the impact of urban compactness on the utility of non-automobile non-commuting travel has not been duly examined. On this ground, to better explain the effects that urban compactness has on travel behavior, this dissertation refines the concept of travel utility using two additions to the microeconomic utility theory: activity-based utility theory of derived travel demand and approaches to positive utility of travel. Accordingly, it designs a conceptual model that specifies travel utility as an intermediary between urban compactness and travel behavior and examines the behavior associated with and utility derived from travel mode choices for alternative purposes of travel. Twenty individual models are derived from the conceptual model and tested within the context of Seoul, Korea, using a confirmatory approach of structural equation modeling and data from geographic information systems and a structured sample survey, which is initially designed and validated by semi-structured interviews and subsequent statistical tests. By comparing the individual models, this research concludes that the urban compactness effect on travel behavior, represented by trip frequencies and supplemented by mode shares, is better explained when travel utility is considered and if travel purposes are separately examined. Major empirical findings are that urban compactness affects travel behavior mainly by increasing the benefits of travel in comparison to its modest effect on the cost reduction and people’s behavioral response to urban compactness is to shift modes of commuting travel, decrease travel for shopping, and increase travel for leisure. These purpose-specific findings have implications for transportation planners and public health planners by assisting them in linking plans and policies concerning urban compactness to travel purposes.
59

Contribuições ao estudo de implantação de pedágio urbano em São Paulo. / Contributions towards the study of congestion charging systems in São Paulo.

Felipe Ferreira Dias 01 April 2015 (has links)
A Região Metropolitana de São Paulo (RMSP) sofre de sérios problemas de congestionamento, assim como muitas outras cidades de grande porte. Uma possível solução, proposta por pesquisadores de transportes, economia e ciências ambientais, é a implantação de um sistema de congestion charging, chamada no Brasil de pedágio urbano. Um dos objetivos do presente trabalho foi estabelecer os conceitos relacionados a este assunto e ilustrar as principais questões relacionadas à sua implantação. Espera-se que este trabalho possa auxiliar o desenvolvimento de estudos de avaliação da viabilidade e de impactos de sistemas propostos de congestion charging. Para atingir este objetivo, toca-se em diversos assuntos, como a definição de congestionamento e as formas de medi-lo, a base conceitual e teórica dos sistemas de congestion charging e seus diversos esquemas de diferenciação. São expostas também as medidas de mitigação de congestionamento que já foram implantadas na RMSP, quais foram os estudos já desenvolvidos considerando este tipo de política para a RMSP, e casos em que sistemas de congestion charging já foi implantado. Neste trabalho, desenvolveu-se também um modelo de escolha discreta a partir dos dados da Pesquisa Origem e Destino 2007 do METRÔ, onde pessoas deveriam escolher entre \"Transporte Coletivo\" e \"Transporte Público\". Este modelo foi utilizado para avaliar o potencial de impacto na divisão modal e de arrecadação de um congestion charge aplicado ao centro expandido de São Paulo. Adverte-se, porém, que os resultados obtidos são meramente ilustrativos. Mostra-se, também, que é possível avaliar a capacidade ociosa do sistema de transporte coletivo a partir dos dados disponíveis de bilhetagem e de GPS dos ônibus. Este processo é exemplificado através do cálculo de capacidade de uma única viagem de um único ônibus, dada a dificuldade de automatização deste processo para abranger toda a frota. / The São Paulo Metropolitan Region (SPMR) suffers from severe traffic congestion, as do many other large-scale urban areas around the world. A possible solution to this issue, which has been suggested by transportation, economics and environmental researchers, is the implementation of a congestion charging system. One of the objectives of this project is to establish clear concepts and shed light on the main issues regarding these systems by means of a comprehensive literary review. It is expected that this project may help the development of in-depth studies carried in order to evaluate the viability and impacts of congestion charging proposals. In order to achieve this goal, many subjects are addressed, such as the definition of congestion, how its measured, the theoretical backgrounds that support congestion charging schemes, their different degrees of differentiation, which policies were enacted in order to reduce traffic congestion in São Paulo, what considerations and studies have already been developed for Brazil and São Paulo regarding these systems and where have these systems been successfully installed. Later chapters deal with another goal of this project: estimating how a congestion charging system would affect SPMR. This was achieved through a multinomial logit model, where decision-makers choose between \"Public Transportation\" and \"Private Automobile\". The results presented at this phase are merely indicative of certain tendencies and should not be considered final. This project also attempts to show that given the available Automated Fare Collection (AFC) data and Automated Vehicle Location (AVL) data, it is possible to estimate the current public transportation system\'s unused capacity. The author shows this by calculating the capacity of one bus trip using these data, but also explains the difficulties of expanding this analysis to the whole of SPMR\'s public transportation system.
60

Revenue Management in High-Density Urban Parking Districts: Modeling and Evaluation

Roper, Martha Annette 22 February 2010 (has links)
This thesis explores how revenue management (RM) principles would integrate into a parking system, and how advanced reservation-making, coupled with dynamic pricing (based on booking limits) could be used to maximize parking revenue. Detailed here is a comprehensive RM strategy for the parking industry, and an integer programming formulation that maximizes parking revenue over a system of garages is presented. Furthermore, an intelligent parking reservation model is developed that uses an artificial neural network procedure for online reservation decision-making. Next, the work evaluates whether the implementation of a parking RM system in a dense urban parking district (and thus avoiding "trial-and-error" behaviors exhibited by drivers) mitigates urban congestion levels. In order to test this hypothesis, a parallel modeling structure was developed that uses a real-time decision-making model that either accepts or rejects requests for parking via a back-propagation neural network. Coupled with the real-time decision-making model is a micro-simulation model structure used to evaluate the policy's effects on network performance. It is clear from the results that the rate at which parkers renege is a primary determinant of the value of the implementation of RM. All other things being equal, the RM model in which the majority of parkers is directed to their precise parking spot via the most direct route is much more robust to the random elements within the network that can instigate extreme congestion. The thesis then moves from micro-evaluation to macro-evaluation by measuring the performance of the urban parking system from the perspective of the set of relevant stakeholders using the hyperbolic DEA model within the context of the matrix DEA construct. The stakeholder models, including that of the provider, the user, and the community, have defined inputs/outputs to the hyperbolic DEA model, which allows for the inclusion of undesirable outputs such as network delay and incidence of extreme congestion. Another key contribution of this work is that of identifying design issues for current and future dense urban parking districts. Clearly, reneging rate and the tenacity of perspective parkers is a key consideration in cases where RM policy is not implemented. / Ph. D.

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