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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.
41

O comportamento do usuário do transporte aéreo frente à variabilidade do tempo de viagem

Weber, Fernanda David January 2015 (has links)
A demanda por transporte é derivada, e seu resultado está relacionado à necessidade de superar barreiras físicas, envolvendo deslocamentos e, consequentemente, tempo. Como a sociedade moderna é orientada pelo relógio, tempo pode ser considerada uma variável de grande importante na dinâmica diária. Sendo assim, os sistemas de transporte têm papel fundamental para garantir que essa dinâmica seja atendida dentro do esperado. Portanto, os sistemas de transporte devem prover um serviço confiável. Ou seja, a operação dos mesmos deve ser regular, resultando em uma variabilidade mínima no tempo de viagem. Esse trabalho tem por objetivo analisar o comportamento do usuário do transporte aéreo frente à variabilidade do tempo de viagem. Para isso, modelos comportamentais foram estimados a partir de um estudo de caso realizado em Porto Alegre, Rio Grande do Sul, com os viajantes que frequentam o Aeroporto Internacional Salgado Filho. Uma comparação entre diferentes abordagens comportamentais, baseadas na teoria da utilidade esperada, também foi contemplada no estudo, com o intuito de encontrar o melhor modelo representativo do comportamento do público estudado. Os modelos estimados apresentam diferentes formas funcionais não lineares, caracterizando diferentes reações dos tomadores de decisão quando em situações de risco. / The demand for transport is derived, and the result is related to the need to overcome the physical barriers involving displacements and hence time. As modern society is driven by the clock, time can be considered a great important variable in the daily dynamics. Thus, the transport systems has a key role to ensure that this dynamic is met as expected. Therefore, transport systems should provide a reliable service. That is, the operation there of is regular, resulting in a minimal variability in travel time. This work aims to study the air transport user behavior against the variability of travel time. To do this, behavioral models were estimated from a case study conducted in Porto Alegre, Rio Grande do Sul, with travelers attending the Salgado Filho International Airport. A comparison between different behavioral approaches based on expected utility theory, the study was also considered in order to find the best studied model representative of the behavior of the public. The estimated models have different nonlinear functional forms, featuring different reactions of decision-makers when at risk.
42

Avaliação da escolha de rota dos motoristas frente à cobrança de pedágio e rodovias de qualidades distintas

Zignani, Rita de Cassia January 2007 (has links)
A malha rodoviária brasileira é caracterizada por vias com níveis de qualidade heterogêneos. Em geral, rodovias que possuem cobrança de pedágio apresentam melhor estado de conservação. Essa dissertação tem como objetivo avaliar a escolha de rota de diferentes classes de usuários, considerando-se a cobrança de pedágio e a diferença na qualidade das vias. A avaliação envolveu a realização de duas fases de pesquisa. A primeira fase buscou estimar os valores monetários dos atributos de tempo e distância de viagem através da técnica de Preferência Declarada. A segunda fase utilizou estes valores monetários como parâmetros da função de custo generalizado da modelagem de alocação de tráfego para estimar a escolha de rota dos usuários. A partir da metodologia proposta, um estudo de caso foi realizado em um trecho rodoviário que apresenta uma rodovia pedagiada e uma rota concorrente de menor qualidade sem cobrança. Os resultados da aplicação prática não refletiram os dados de fluxo observados nas rodovias avaliadas. A partir desta constatação, um questionário complementar foi elaborado buscando identificar o comportamento habitual dos usuários na região de estudo. Através dos resultados da pesquisa complementar, verificou-se que a maioria dos entrevistados não possuía conhecimento sobre a rota alternativa. A utilização dos dados provenientes destes usuários na modelagem não se mostrou apropriada, uma vez que sua escolha de rota não é baseada nas relações de tempo, distância e penalidades nas vias, consideradas nos modelos de alocação de tráfego. Com isso, pode-se verificar neste estudo que os princípios e limitações das técnicas e ferramentas utilizadas, bem como de sua utilização conjunta, devem ser avaliados. / The Brazilian road system is characterized by roads with heterogeneous level of quality. Generally, tolled roads present better quality conditions than those not tolled. This work aimed to evaluate the route choice of different user’s classes considering toll collection and roads of different qualities. This evaluation was carried out with a methodology composed of two phases preceded by definition of the study region and the users classes considered. The first phase intended to estimate monetary values of time and distance through the Stated Preference technique. The second phase used these monetary values as parameters in an assignment model generalized cost function to estimate user’s route choice. From the proposal methodology, a case study was carried out in a road stretch that presents a tolled highway and a worse quality and without charge alternative route. The practical application results did not reflected the observed flow data in the evaluated highways. From these results, a complementary questionnaire was elaborated to identify the habitual user’s behavior in the study region. It was observed that the majority of the interviewed ones did not have knowledge of the alternative route. Using these data in the modeling was not appropriate because their route choice is not based in time, distance and road penalties relationship like in the assignment models. Thus, it was verified in this study that the principles and limitation of the used techniques and tools, as well as the joint use of these, might be taken in consideration.
43

Proposta de método para análise de demanda para um modo combinado de transporte associado a estacionamentos dissuasórios

Moscarelli, Fabiane da Cruz January 2009 (has links)
Estacionamentos dissuasórios são locais destinados a transferência de um modo de transporte de baixa capacidade, automóvel, para um modo de transporte de alta capacidade. A principal vantagem do uso do estacionamento dissuasório, em relação às demais medidas de gerenciamento de demanda, é a manutenção da flexibilidade, associada às viagens de automóvel, no trecho inicial da viagem. Este trabalho tem como objetivo avaliar a demanda para um modo combinado de transporte composto por automóvel, estacionamento dissuasório e transporte público, obtida pela atração de viagens atualmente realizadas em automóvel. É proposto um método de previsão de demanda baseado em quatro etapas dentre as quais estão a modelagem das viagens de automóvel, que fornecerá os dados necessários para as etapas posteriores, e a aplicação de um modelo Logit para previsão da divisão modal. O método foi aplicado a um estudo de caso que consiste na construção de três estacionamentos dissuasórios, ao longo do trajeto de uma linha de transporte público atendida por BRT (Bus Rapid Transit), na cidade de Porto Alegre. Os resultados permitiram avaliar a influência dos atributos, descritivos de cada modo de transporte, na escolha do modo de viagem pelo usuário e identificar o percentual de transferência de viagens para o modo combinado, em nível agregado, considerando o total de viagens, e em nível desagregado através da análise por zonas de origem e destino das viagens. O método foi considerado adequado e os resultados foram coerentes com a literatura. / Park and rides are places to transfer from one low capacity mode of transport, car for example, to a high capacity transportation mode. The main advantage of using park and rides, when comparing to other policies of demand management, is to maintain flexibility, related to traveling by car, in the first stage of the journey. This study aims to analize the demand for a combinated transport mode composed for car, park and ride and public transport, obtained by the attraction of trips currently made by car. In this work, a method based on four steps is proposed for demand analize, and among them are the modeling of car trips, which will provide the necessary data for the subsequent stages, and the implementation of a Logit model for predicting the modal split. The method was applied to a case study, which consists in the construction of three park and rides along the route of a public transport line served by a BRT (Bus Rapid Transit), in Porto Alegre. The results allowed to evaluate the influence of the attributes that describe each mode of transport in the user’s trips mode choices and to identify the percentage of transfer of trips to the combined mode, in an aggregated level, considering the total travel, and in a disaggregated level by analyzing the origins and destination zones. The method was considered appropriated and the results were similar to the literature.
44

Understanding the Value of Travel Time Reliability for Freight Transportation to Support Freight Planning

Shams, Kollol, 3085942 18 November 2016 (has links)
Today’s logistics practices are moving from inventory-based push supply chains to replenishment-based pull supply chains, leading to a lower and less centralized inventory, smaller shipment sizes, and more just-in-time deliveries. As a result, industries are now demanding greater reliability in freight transportation. Delays and uncertainty in freight transportation translate directly into additional inventory, higher manufacturing costs, less economic competitiveness for businesses, and higher costs of goods that are being passed on to the consumers. Given the growing demand in freight transportation, the emerging needs to better understand freight behavior for better policy and investment decisions, and the increasing role of reliability in freight transportation, this research aims at providing a) better understanding of how the freight system users value travel time reliability in their transportation decisions, and b) advanced methods in quantifying the user’s willingness to pay for the improvement of transportation related attributes, particularly travel time reliability. To understand how the freight industry values travel time reliability in their transportation decisions, and particularly the presence of user heterogeneity, this research designed and conducted a stated preference (SP) survey for freight users in road transportation. Based on the feedback received during the pilot stage, reliability was measured as the standard deviation of travel time and presented as a frequency of on-time and late delivery in the choice scenarios. The survey collected 1,226 responses from 159 firms in Florida between January and May 2016 via online and paper methods. Various modeling approaches were explored to estimate the willingness to pay (WTP) measures among freight users, including multinomial logit (MNL) and mixed logit model. Market segmentation and interaction modeling techniques were employed to investigate preference variations among user groups, commodity groups, product type, and various other shipment characteristics, including shipping distance and weight. In general, across all groups in the sample, values of $37.00 per shipment-hour ($1.53 per ton-hour) for travel time savings and $55.00 per shipment-hour ($3.81 per ton- hour) for improvements of reliability were found in this research. Furthermore, while investigating the effects of shipping characteristics on the user’s preference in WTP, the results suggested that shipping distance and weight were the two most important variables. The results of the study help advance the understanding of the impact of the performance of transportation systems on freight transportation, which will lead to policy and investment decisions that better serve the needs of the freight community.
45

Student preferences for accommodation at a Cape Town University: an application of the stated preference approach

Edwards, Sarita January 2019 (has links)
Thesis (Master of Marketing)--Cape Peninsula University of Technology, 2019 / This thesis sought to investigate students’ preferences regarding university accommodation. The object was to identify the aspects and elements of housing that students deemed most desirable. The research also aimed to ascertain which socio-demographic variables might serve as predictors of preference in student housing. The thesis focused on student housing at a university in Cape Town, South Africa. The researcher adopted a stated preference approach, applying direct measurement and conjoint analysis methods to answer the research questions. The study commenced with qualitative exploratory research, including a literature review and focus group interviews with students. This was followed by collection of cross-sectional quantitative data using person-administered, structured questionnaires distributed among students at the university. SPSS software was used to analyse a total of 457 completed questionnaires. The direct measurement results indicated that most students prioritised convenience, safety, cost and privacy when it came to choosing accommodation. The three most important attributes as ranked by respondents were having unlimited free WiFi, the inclusion of a 24-hour computer lab in the building, and 24-hour on-site security. In addition, respondents favoured the presence of a convenience shop/kiosk in the residence, followed by sharing showers with students of their own gender, and being within walking distance of campus. Preferences for some but not all the dimensions of accommodation appeared to be influenced by gender, age group and study level. When indicating their willingness to pay (WTP) for a variety of elements relating to accommodation, it emerged that the question of sharing the space in their room – their living and learning space – was very important to the students. The results showed that, apart from having unlimited WiFi and 24-hour on-site security, the aspects for which respondents were prepared to pay most concerned the private space of the individual, e.g. room privacy and room size, as well as having their own toilet and shower. WTP attributes also varied among students according to age group, gender and level of study. Results from the stated preference (conjoint) experiment analysis showed that students were most sensitive about the sharing of ablutions and number of roommates, strongly preferring private rooms and facilities, or sharing with fewer other students. Monthly rent is next most influential, followed by distance from campus. The model also showed significant differences in the preferences of students based on their gender. Research in this field is overdue because, owing to recent increases in the tertiary student population in South Africa, there is a growing shortage of student accommodation. Current and future student housing needs must be assessed, and any such assessment requires a thorough grasp of current student accommodation preferences. The results of this research thus contribute to the knowledge and understanding available to managers and developers of student accommodation regarding students’ requirements and preferences. The findings can serve as a set of guidelines for developers of student housing and as a foundation for formulating associated marketing strategies. Despite the existence of extensive research on student housing, few studies have focused on the preferences of students in developing countries, and even fewer in South Africa. This research seeks to fill this gap by increasing awareness and understanding of students’ preferences with regard to university accommodation.
46

Is there a willingness to pay for shade provision as part of cycling urban infrastructure? Eliciting attributes of a discrete choice experiment in Neiva, Colombia

Arce Correa, Jorge Andres January 2023 (has links)
This manuscript reports on an exploration of whether shade provision is valued by urban users of cycling infrastructure. A description of the elicitation process has been outlined in order to build a general but detailed analysis of the different stages included in the exercise of attribute elicitation. As a departure point, a thorough literature review was conducted in order to establish a state of the art’s scenario. Different kinds of attributes that have been evaluated previously within discrete choice experiments and other relatable methods linked to bicycle commuting and bike route choices were compiled, however, shade appeared as an overlooked attribute. From this, a theoretical and methodological approach based on welfare economics and, the concept of willingness to pay as an indicator of shade provision’s value is proposed for the context of Neiva, Colombia, a medium size city in a developing country. Preliminary focus groups were conducted to build a surveying tool for eliciting the proposed attribute and gathered more contextual information. Finally, a pilot survey was launched in order to test the perceived value of shade and its importance for commuters. Special attention is devoted to the description of how the tools and methods were used in order to help future efforts. Several sets of data and information were reviewed and contrasted in order to build an accurate image of the current status of shade within the local commuters’ minds, what barriers were found while executing the research plan, and what can be some important implications for future urban planning studies and sustainable mobility research. Several different commuting conditions and individual realities were found, nonetheless, the existence of valuing shade provision was pervasive across all the surveyed university students and graduated staff. Furthermore, the benefits were perceived as socially broad, even by motorized, non-walking, and cycling commuters. Other valuable insights were found, like the effect of corruption when asking for policy implementation, further research needs to be conducted due to sampling limitations, the scarcity of previous research aimed at the subject, and for gathering more information about how acknowledging the attribute might be potentially critical for the future.
47

The behavioral impacts of uncertain access to free floating bicycle services / アクセスの不確実性がフリーフロート型のシェアサイクルの行動にもたらす影響に関する研究

YAO, ZIANG 26 September 2022 (has links)
京都大学 / 新制・課程博士 / 博士(工学) / 甲第24217号 / 工博第5045号 / 新制||工||1788(附属図書館) / 京都大学大学院工学研究科都市社会工学専攻 / (主査)教授 山田 忠史, 教授 藤井 聡, 准教授 SCHMOECKER Jan-Dirk / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
48

Evaluation of a Bicycle Facility User Survey in the Dayton, Ohio Area

Siler, Emily A. 23 September 2016 (has links)
No description available.
49

Investigating Real-Time Employer-Based Ridesharing Preferences Based on Stated Preference Survey Data

Shay, Nathan Michael January 2016 (has links)
No description available.
50

Valuing Biological diversity in Navarino island, Cape Horn Archipelago, Chile - a choice experiment approach / Valoración de la diversidad biológica en isla Navarino, Archipiélago Cabo de Hornos, Chile - una aproximación con experimento de elección

Cerda, Claudia 03 July 2006 (has links)
No description available.

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