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Forma urbana e rotas de pedestresVargas, Júlio Celso Borello January 2015 (has links)
O estímulo aos modos ativos de viagem através de modificações na forma urbana - infraestrutura, edificações e atividades - é objeto do planejamento das cidades contemporâneas desde que os problemas do transporte motorizado se revelaram críticos e contrários à ideia de sustentabilidade urbana. Congestionamentos, poluição, custos monetários e sociais elevados estão associados ao modelo de urbanização e mobilidade da maioria das cidades, especialmente nos países em desenvolvimento, onde a explosão da frota motorizada é concomitante à aceleração dos processos de urbanização e espalhamento urbano. Mais recentemente, a revelação de relações de causalidade entre o excesso de utilização dos veículos particulares e problemas de saúde crônica das populações urbanas levou a um crescimento das pesquisas e iniciativas de estímulo às caminhadas como modo de transporte. Também o interesse pela qualidade da experiência da vida na cidade veio somar-se a este corpo de conhecimento, trazendo as ideias de vitalidade urbana e urbanidade para junto dos estudos de caminhabilidade. O interesse extrapolou a análise de demanda agregada que visa o incremento do modo a pé e passou a dar atenção aos caminhos pelos quais as pessoas se movimentam, conectando origens e destinos nos interior das cidades. Este trabalho procura avançar neste aspecto ao propor um método de avaliação dos atributos da forma urbana baseado no monitoramento de caminhantes com dispositivos de posicionamento global (GPS) e modelos de escolha discreta. Um estudo na cidade de Porto Alegre acompanhou indivíduos durante os anos de 2011 a 2014 e, através da representação de diversos atributos urbanos em ambiente SIG, associou as trajetórias realizadas com as características da forma da cidade, concluindo que elas influenciam a utilidade percebida das alternativas de caminho e, portanto, atuam sobre o processo decisório dos pedestres. Para além da simples distância ou declividade, outras características como o tamanho dos trechos, a hierarquia das vias, a presença de prédios marcantes e espaços abertos e a densidade de edificações ao longo dos eixos revelaram-se influentes neste processo. Poucas intersecções e cruzamentos, predomínio de vias amigáveis ao pedestre e edificações arranjadas de forma menos densa são alguns dos atributos que apresentaram maior relevância para a decisão de “por onde ir” no âmbito deste estudo. A amostra relativamente pequena e a concentração das viagens no entorno do Parque Farroupilha e do campus da UFRGS não permitem generalizar os resultados. Porém, o estudo pode ser considerado válido enquanto exploração, pois constrói uma metodologia que pode ser ampliada e aplicada em outros contextos. Além disso, os resultados revelam particularidades da realidade local que parecem indicar a existência de diferenças comportamentais significativas em relação às cidades do primeiro mundo, tornando-o promissor como instrumento de suporte a políticas e projetos de mobilidade urbana sustentável no Brasil. / Since motorized transport problems have proved to be critical and contrary to the concept of urban sustainability, the idea of increasing the active travel modes through changes in urban form is a key subject of today´s mobility agenda. Traffic congestion, air pollution and severe monetary and social costs are associated with the current patterns of urbanization and mobility, especially in developing countries, where an explosive motorized fleet growth occurs simultaneously to an acceleration of urbanization and sprawl processes. Most recently evidences of a causal relationship between massive use of private vehicles and chronic health disorders have led to an increase in research about walking as an effective and clean mode of transportation. Also, the interest about the quality of life experience in the city came to add up to this body of knowledge, bringing in ideas of livability to walkability studies. Beyond the aggregate demand studies that aim to increase the walking mode share, there is now a growing interest on more localized aspects of the walking phenomenon - the routes - trying to understand the ways in which people travel on foot when connecting origins and destinations. This work proposes a method based on assessing data from actually taken walking trips using GPS devices and on modeling pedestrian´s choice behavior using discrete choice models. A study in the city of Porto Alegre, south of Brazil, followed 82 individuals for three consecutive days and, through the representation of several layers of urban data in a GIS environment, associated their trajectories with the main urban form attributes to allow the modeling experiment. The results show that the built environment features play an important role as a decision attribute, producing perceived utility/disutility on the decision-makers´ minds. They indicated that, in addition to the basic travel effort attributes such as trip distance or street slope, other factors such as the straightness of the trip, the road hierarchy, the presence of busy intersections, landmark buildings, noticeable public spaces and the density of buildings along the walking stretches indeed influence the route choice. The relatively small sample size and the spatial clustering of trips around the city´s central area doesn´t allow to the generalization of results. However, the study can be taken as a valid exploratory analysis, since it builds up a methodology that can be expanded and applied in other urban contexts. Furthermore, the results reveal some particular local features that indicate the existence of significant behavioral differences from the developed cities where previous similar studies were performed. These qualities make the proposed framework a promising decision support tool for sustainable urban mobility projects in Brazil.
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Forma urbana e rotas de pedestresVargas, Júlio Celso Borello January 2015 (has links)
O estímulo aos modos ativos de viagem através de modificações na forma urbana - infraestrutura, edificações e atividades - é objeto do planejamento das cidades contemporâneas desde que os problemas do transporte motorizado se revelaram críticos e contrários à ideia de sustentabilidade urbana. Congestionamentos, poluição, custos monetários e sociais elevados estão associados ao modelo de urbanização e mobilidade da maioria das cidades, especialmente nos países em desenvolvimento, onde a explosão da frota motorizada é concomitante à aceleração dos processos de urbanização e espalhamento urbano. Mais recentemente, a revelação de relações de causalidade entre o excesso de utilização dos veículos particulares e problemas de saúde crônica das populações urbanas levou a um crescimento das pesquisas e iniciativas de estímulo às caminhadas como modo de transporte. Também o interesse pela qualidade da experiência da vida na cidade veio somar-se a este corpo de conhecimento, trazendo as ideias de vitalidade urbana e urbanidade para junto dos estudos de caminhabilidade. O interesse extrapolou a análise de demanda agregada que visa o incremento do modo a pé e passou a dar atenção aos caminhos pelos quais as pessoas se movimentam, conectando origens e destinos nos interior das cidades. Este trabalho procura avançar neste aspecto ao propor um método de avaliação dos atributos da forma urbana baseado no monitoramento de caminhantes com dispositivos de posicionamento global (GPS) e modelos de escolha discreta. Um estudo na cidade de Porto Alegre acompanhou indivíduos durante os anos de 2011 a 2014 e, através da representação de diversos atributos urbanos em ambiente SIG, associou as trajetórias realizadas com as características da forma da cidade, concluindo que elas influenciam a utilidade percebida das alternativas de caminho e, portanto, atuam sobre o processo decisório dos pedestres. Para além da simples distância ou declividade, outras características como o tamanho dos trechos, a hierarquia das vias, a presença de prédios marcantes e espaços abertos e a densidade de edificações ao longo dos eixos revelaram-se influentes neste processo. Poucas intersecções e cruzamentos, predomínio de vias amigáveis ao pedestre e edificações arranjadas de forma menos densa são alguns dos atributos que apresentaram maior relevância para a decisão de “por onde ir” no âmbito deste estudo. A amostra relativamente pequena e a concentração das viagens no entorno do Parque Farroupilha e do campus da UFRGS não permitem generalizar os resultados. Porém, o estudo pode ser considerado válido enquanto exploração, pois constrói uma metodologia que pode ser ampliada e aplicada em outros contextos. Além disso, os resultados revelam particularidades da realidade local que parecem indicar a existência de diferenças comportamentais significativas em relação às cidades do primeiro mundo, tornando-o promissor como instrumento de suporte a políticas e projetos de mobilidade urbana sustentável no Brasil. / Since motorized transport problems have proved to be critical and contrary to the concept of urban sustainability, the idea of increasing the active travel modes through changes in urban form is a key subject of today´s mobility agenda. Traffic congestion, air pollution and severe monetary and social costs are associated with the current patterns of urbanization and mobility, especially in developing countries, where an explosive motorized fleet growth occurs simultaneously to an acceleration of urbanization and sprawl processes. Most recently evidences of a causal relationship between massive use of private vehicles and chronic health disorders have led to an increase in research about walking as an effective and clean mode of transportation. Also, the interest about the quality of life experience in the city came to add up to this body of knowledge, bringing in ideas of livability to walkability studies. Beyond the aggregate demand studies that aim to increase the walking mode share, there is now a growing interest on more localized aspects of the walking phenomenon - the routes - trying to understand the ways in which people travel on foot when connecting origins and destinations. This work proposes a method based on assessing data from actually taken walking trips using GPS devices and on modeling pedestrian´s choice behavior using discrete choice models. A study in the city of Porto Alegre, south of Brazil, followed 82 individuals for three consecutive days and, through the representation of several layers of urban data in a GIS environment, associated their trajectories with the main urban form attributes to allow the modeling experiment. The results show that the built environment features play an important role as a decision attribute, producing perceived utility/disutility on the decision-makers´ minds. They indicated that, in addition to the basic travel effort attributes such as trip distance or street slope, other factors such as the straightness of the trip, the road hierarchy, the presence of busy intersections, landmark buildings, noticeable public spaces and the density of buildings along the walking stretches indeed influence the route choice. The relatively small sample size and the spatial clustering of trips around the city´s central area doesn´t allow to the generalization of results. However, the study can be taken as a valid exploratory analysis, since it builds up a methodology that can be expanded and applied in other urban contexts. Furthermore, the results reveal some particular local features that indicate the existence of significant behavioral differences from the developed cities where previous similar studies were performed. These qualities make the proposed framework a promising decision support tool for sustainable urban mobility projects in Brazil.
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Modelagem de pedestres : comportamento em travessia e escolha de rotaWerberich, Bruno Rocha January 2013 (has links)
Esta dissertação busca identificar aspectos carentes de melhorias na modelagem de pedestres. A modelagem do comportamento de pedestres se inicia pelo entendimento de seu processo decisório, entendendo como ele se desloca, realiza escolha de rotas, interage com outros pedestres, veículos, obstáculos, etc. Os modelos de simulação de pedestres estão hoje aptos a representar de forma bastante realista o deslocamento dos mesmos, entretanto, a simulação conjunta com veículos apresenta ainda alguns aspectos fracos devido as grandes diferenças de abordagem na modelagem dos dois modos. A representação da travessia de pedestres nos modelos de simulação tradicionais apresenta limitações que podem impactar nos resultados gerados pelos simuladores. Este trabalho enumera diversos comportamentos de pedestres decorrentes da interação com veículos, no momento da travessia, que geralmente não estão presentes nos simuladores. Uma vez identificados estes comportamentos, uma pesquisa foi realizada com usuários do sistema viário, com idades entre 22 e 60 anos, para avaliar o quanto estes comportamentos são frequentes e importantes na estimativa de tempos de viagem dos pedestres. O comportamento indicado pelos entrevistados como mais impactante nos tempos de viagem foi o de “busca por brecha em caminhada”, onde o pedestre percorre trechos na lateral da via, enquanto observa possíveis brechas na corrente de tráfego para realizar sua travessia. O referido comportamento foi então modelado e agregado a um modelo de simulação de pedestres. Os resultados mostraram que a inclusão do novo comportamento provoca redução significativa dos tempos médios de viagem dos pedestres e que a simulação pode ser mais condizente com o comportamento real de pedestres em diversos ambientes urbanos. Para representar o comportamento de um pedestre em um ambiente urbano, é preciso também estudar como ele escolhe suas rotas. No processo de escolha de rotas, o pedestre é influenciado por diversos fatores, como hábitos pessoais, o número de cruzamentos, níveis de poluição e de ruído, segurança, abrigo de condições climáticas ruins, e estimulação do ambiente. Para representar o comportamento de escolha de rota dos pedestres, foi desenvolvido um modelo que considera a interação entre pedestres como uma impedância alterando a rota do pedestre. O estudo foi inspirado por equações de forças de atrito, considerando que pedestres tendem a evitar passar próximo de outros pedestres com elevada velocidade relativa. Para escolher uma rota o pedestre realiza uma ponderação entre a impedância e a distância a ser percorrida. O modelo foi capaz de reproduzir comportamentos emergentes da interação entre os agentes, permitindo concluir que as equações de forças de atrito adotadas nesta modelagem podem ser uma abordagem válida na representação da escolha de rotas de pedestres, podendo também ser uma forma indireta de avaliação de atrasos. / This dissertation aims to identify aspects in need of improvement in modeling pedestrians. The modeling of pedestrian behavior begins by understanding their decision making process, understanding how people move, make route choice, interact with other pedestrians, vehicles, obstacles, etc. Simulation models of pedestrians are able to represent the way they move quite realistically, however, the combined simulation of pedestrians and vehicles still presenting some poor aspects due to the wide differences in the modeling approach of the two modes. The pedestrian road crossing representation in the traditional simulation models has limitations that may impact on the results generated by the simulators. This dissertation lists several behaviors arising from the interaction of pedestrians with vehicles at road crossing situations, which are generally not present in the simulators. Having identified these behaviors, a survey was conducted with pedestrians, aged between 22 and 60 years old, to evaluate how these behaviors are frequent and important to estimate travel times. The behavior indicated by the interviewees as more impactful in the travel times was the “search for a gap while walking”, describing the pedestrian that walks laterally to the road, in the sidewalk, at the same time that is trying to cross the road, looking for gaps in the traffic stream. Such behavior was modeled and then aggregated at a simulation model of pedestrians. Results showed that the inclusion of the new behavior causes significant reduction in average travel time for pedestrians and that the simulation can be more consistent with the actual behavior of pedestrians in different urban environments. To represent a pedestrian behavior in an urban environment, it is also necessary to study how he chooses their route. At the route choice process, the pedestrian is influenced by several factors, such as personal habits, the number of road crossings, levels of pollution and noise, safety, shelter from bad weather, and other stimulation of the environment. In order to represent the pedestrians route choice behavior was devised a model that considers the interaction between pedestrians as an impedance to alter pedestrians route. The study is inspired by friction forces equations, considering that pedestrians avoid passing near other pedestrians with high relative velocity. To choose a route a pedestrian consider a balance between the impedance and the path length. The model is able to reproduces emergent behavior between agents, allowing the assumption that friction equations adopted in this modeling may provide a suitable approach to route choice behavior and can also be used as an indirect measure of pedestrians delay.
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Development of Truck Route Choice Data Using Truck GPSKamali, Mohammadreza 06 November 2015 (has links)
Over the past few decades, the value and weight of freight shipments have grown steadily in both developed and developing countries. A recent statistic in the U.S. reveals that weight of shipments increased from 18,879 to 19,662 million tons between 2007 and 2012 (1). It is also expected that this amount will increase to 28,520 million tons by 2040 (1). It is worth mentioning that 67 percent of shipments are shipped by truck mode in 2012. The monetary value of freight is expected to escalate even faster than weight. This value is estimated to rise from US$ 882 per ton in 2007 to US$ 1,377 per ton in 2040. As a result, freight transportation management and modeling has aroused the interest of both public sector and groups of firms to improve the efficiency of the business operations. Traffic assignment plays a central role in the current freight modeling, and freight route analysis is of fundamental importance in understanding the truck flows explicitly.
In the first part of this thesis, large streams of truck-GPS data from the American Transportation Research Institute (ATRI) are cleaned, processed, and analyzed using easy to implement and practical procedures to study the diversity of observed truck routes between a given origin-destination (OD) pair. This is because, for any given OD pair, the analyst could observe and compare the route choices of a large number of trips, as opposed to observing only one or a few trips. Doing so helps in quantifying the number of different routes taken by trucks between an OD pair and paves the way for a systematic analysis of the “diversity” in route choices between any OD pair. This thesis develops methods to measure the diversity of routes between a given OD pair and identifies unique routes used between the given OD pair. From a practical standpoint, such analysis of the diversity in observed route choices helps in improving the existing route choice set generation algorithms.
In the second part of the thesis, the methodologies developed in the first part are implemented in an FDOT sponsored project entitled “GPS Data for Truck-Route Choice Analysis of Port Everglades Petroleum Commodity Flows”. This project aims to use truck-GPS data from ATRI to derive petroleum tanker trucks’ travel path (or route) information, describing the routes that the tanker trucks take to travel from Port Everglades to their final delivery points.
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Modelagem de pedestres : comportamento em travessia e escolha de rotaWerberich, Bruno Rocha January 2013 (has links)
Esta dissertação busca identificar aspectos carentes de melhorias na modelagem de pedestres. A modelagem do comportamento de pedestres se inicia pelo entendimento de seu processo decisório, entendendo como ele se desloca, realiza escolha de rotas, interage com outros pedestres, veículos, obstáculos, etc. Os modelos de simulação de pedestres estão hoje aptos a representar de forma bastante realista o deslocamento dos mesmos, entretanto, a simulação conjunta com veículos apresenta ainda alguns aspectos fracos devido as grandes diferenças de abordagem na modelagem dos dois modos. A representação da travessia de pedestres nos modelos de simulação tradicionais apresenta limitações que podem impactar nos resultados gerados pelos simuladores. Este trabalho enumera diversos comportamentos de pedestres decorrentes da interação com veículos, no momento da travessia, que geralmente não estão presentes nos simuladores. Uma vez identificados estes comportamentos, uma pesquisa foi realizada com usuários do sistema viário, com idades entre 22 e 60 anos, para avaliar o quanto estes comportamentos são frequentes e importantes na estimativa de tempos de viagem dos pedestres. O comportamento indicado pelos entrevistados como mais impactante nos tempos de viagem foi o de “busca por brecha em caminhada”, onde o pedestre percorre trechos na lateral da via, enquanto observa possíveis brechas na corrente de tráfego para realizar sua travessia. O referido comportamento foi então modelado e agregado a um modelo de simulação de pedestres. Os resultados mostraram que a inclusão do novo comportamento provoca redução significativa dos tempos médios de viagem dos pedestres e que a simulação pode ser mais condizente com o comportamento real de pedestres em diversos ambientes urbanos. Para representar o comportamento de um pedestre em um ambiente urbano, é preciso também estudar como ele escolhe suas rotas. No processo de escolha de rotas, o pedestre é influenciado por diversos fatores, como hábitos pessoais, o número de cruzamentos, níveis de poluição e de ruído, segurança, abrigo de condições climáticas ruins, e estimulação do ambiente. Para representar o comportamento de escolha de rota dos pedestres, foi desenvolvido um modelo que considera a interação entre pedestres como uma impedância alterando a rota do pedestre. O estudo foi inspirado por equações de forças de atrito, considerando que pedestres tendem a evitar passar próximo de outros pedestres com elevada velocidade relativa. Para escolher uma rota o pedestre realiza uma ponderação entre a impedância e a distância a ser percorrida. O modelo foi capaz de reproduzir comportamentos emergentes da interação entre os agentes, permitindo concluir que as equações de forças de atrito adotadas nesta modelagem podem ser uma abordagem válida na representação da escolha de rotas de pedestres, podendo também ser uma forma indireta de avaliação de atrasos. / This dissertation aims to identify aspects in need of improvement in modeling pedestrians. The modeling of pedestrian behavior begins by understanding their decision making process, understanding how people move, make route choice, interact with other pedestrians, vehicles, obstacles, etc. Simulation models of pedestrians are able to represent the way they move quite realistically, however, the combined simulation of pedestrians and vehicles still presenting some poor aspects due to the wide differences in the modeling approach of the two modes. The pedestrian road crossing representation in the traditional simulation models has limitations that may impact on the results generated by the simulators. This dissertation lists several behaviors arising from the interaction of pedestrians with vehicles at road crossing situations, which are generally not present in the simulators. Having identified these behaviors, a survey was conducted with pedestrians, aged between 22 and 60 years old, to evaluate how these behaviors are frequent and important to estimate travel times. The behavior indicated by the interviewees as more impactful in the travel times was the “search for a gap while walking”, describing the pedestrian that walks laterally to the road, in the sidewalk, at the same time that is trying to cross the road, looking for gaps in the traffic stream. Such behavior was modeled and then aggregated at a simulation model of pedestrians. Results showed that the inclusion of the new behavior causes significant reduction in average travel time for pedestrians and that the simulation can be more consistent with the actual behavior of pedestrians in different urban environments. To represent a pedestrian behavior in an urban environment, it is also necessary to study how he chooses their route. At the route choice process, the pedestrian is influenced by several factors, such as personal habits, the number of road crossings, levels of pollution and noise, safety, shelter from bad weather, and other stimulation of the environment. In order to represent the pedestrians route choice behavior was devised a model that considers the interaction between pedestrians as an impedance to alter pedestrians route. The study is inspired by friction forces equations, considering that pedestrians avoid passing near other pedestrians with high relative velocity. To choose a route a pedestrian consider a balance between the impedance and the path length. The model is able to reproduces emergent behavior between agents, allowing the assumption that friction equations adopted in this modeling may provide a suitable approach to route choice behavior and can also be used as an indirect measure of pedestrians delay.
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Estimation of Tourist Travel Patterns with Recursive Logit Models based on Wi-Fi Data with Kyoto City Case Study / Wi-Fiデータを用いた再帰的ロジットモデルによる観光行動パターンの推定に関する研究-京都市を例として-Gao, Yuhan 23 March 2021 (has links)
京都大学 / 新制・課程博士 / 博士(工学) / 甲第23178号 / 工博第4822号 / 新制||工||1753(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
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Akzeptanz-und Befolgungsgrade von VerkehrsleitsystemenKurreck, Claudia 01 March 2016 (has links)
Effects of route choice by Advanced Traveller Information Service (ATIS) were investigated in a study. To support the route choice behavior, the possibility of using collective traffic management systems which are mounted in public road space. To investigate what factors and what information must be communicated to the driver so that they change their route. In this work ATIS be examined in city traffic. The empirical study will verify what the role of ATIS is and which characteristics of the Information Service influence the decision strat-egy. Variable Message Signs will inform the driver while driving on possible alternatives and issues that have a major impact on the driver\\\'s decision. Here, the driver does not always make a decision within the meaning of homo oeconomicus, which increases the subjective benefits. But other determinants such as socio-demographic variables interacts with decision.
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Are Dominant Routes the Least Stressful Routes in a Bike Share System? An Investigation of Hamilton Bike Share using Weighted Level of Traffic StressUbhi, Rajveer January 2021 (has links)
Level of Traffic Stress (LTS) is a four-level system that classifies the stress experienced by cyclists on road segments and at intersections. While LTS has been used in past studies to assess cycling connectivity, accessibility, and safety, very little is known concerning its influence on cycling preferences. This study investigates this topic using a dataset containing 323,163 unique GPS trajectories of Hamilton Bike Share (HBS) users collected over a 12-month period (January 1st to December 31st, 2019). A GIS-based map-matching algorithm is used to generate users’ routes from these trajectories along with attributes such as route length, number of intersections, and number of turns. Unique routes and their use frequencies are then extracted from all routes. The most popular routes between bike share hub (station) pairs are then identified as dominant routes while shortest distance routes are derived by minimizing distance traveled. Weighted level of traffic stress (WLTS), a novel measure of impedance (travel cost) developed for this study, is used to derive the least stressful routes between hub pairs. The three types of routes are compared statistically. The comparison finds that HBS users tend to choose longer routes with bicycle infrastructure in an effort to reduce their traffic stress. However, they do not choose to minimize traffic stress in its entirety by choosing the lowest WLTS routes. In other words, dominant routes are not the least stressful routes in a bike share system. Likewise, minimizing distance is not the sole consideration of HBS users. The findings suggest that other factors also influence route choice. This study not only enhances our understanding of cyclist route preferences with respect to LTS, it also presents a novel measure of impedance – WLTS – that could be used when planning new cycling infrastructure or as an alternative means to route cyclists between origins and destinations. / Thesis / Master of Science (MSc)
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User Equilibrium in a Disrupted Network with Real-Time Information and Heterogeneous Risk AttitudePothering, Ryan J 01 January 2012 (has links) (PDF)
The traffic network is subject to random disruptions, such as incidents, bad weather, or other drivers’ random behavior. A traveler’s route choice behavior in such a network is thus affected by the probabilities of such disruptions, his/her attitude towards risk, and real-time information on revealed traffic conditions that could potentially reduce the level of uncertainty due to the disruptions. As the road network’s performance is de-termined collectively by all travelers’ choices, it is also affected by these factors. This thesis features the development of a multi-class user equilibrium model based on hetero-geneous risk attitude distributions and a user equilibrium model based on various disrup-tion probabilities and information penetration rates that can be used to perform sensitivity analyses for a traffic network. The method of successive average (MSA) is used to solve for the equilibrium conditions. Laboratory experimental data are used to calibrate the risk attitude model. A sample sensitivity analysis is performed to show the disruption and in-formation penetration effects on network performance. Initial calibrations show promis-ing results for route flow predictions in a congested network with respect to heterogene-ous attitude. With respect to disruption probability and information access, having too v high information penetration will not improve the network’s performance, while having a small disruption probability can improve traffic conditions in the network
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Travelers' Route Choice Behavior in Risky NetworksTian, Hengliang 01 September 2013 (has links)
The accurate modeling of travelers’ route choice decision making when faced with unreliable (risky) travel times is necessary for the assessment of policies aimed at improving travel time reliability. Two major objectives are studied in this thesis. The first objective is to evaluate the applicability of a process model to route choice under risk where the actual process of decision making is captured. Traditionally, we adopt “as-if” econometric models to predict people’s route choice decisions. The second objective is to investigate travelers’ capability to incorporate future real-time traffic information into their current route choice decision making. Two separate stated preference (SP) surveys were conducted for each objective. The first SP survey used an interactive map in a computer based test. The second SP survey used a full-scale high-fidelity driving simulator.
Compared with econometric models, process models have been rarely investigated in travel decision making under risk. A process model aims to describe the actual decision making procedure and could potentially provide a better explanation to route choice behavior. A process model, Priority Heuristic (PH), developed by Brandstatter et al. (2006) is introduced to the travel choice context and its probabilistic version, Probabilistic Priority Heuristic (PPH), is developed and estimated in this study. With data collected from a stated preference (SP) survey which is based on an animated computer interface, one econometric model, Rank-Dependent Expected Utility (RDEU) model, and two other alternative models were compared with the PPH model in a cross validation test to investigate their data-fitting and predictive performance. Our results show that the PPH model outperforms the RDEU model in both data-fitting and predictive performance. This suggests that the process modeling paradigm could be a promising new area in travel behavior research.
With the advance of information and telecommunication technology, real-time traffic information is increasingly more available to help travelers make informed route choice decisions when faced with unreliable travel times. A strategic route choice refers to a decision taking into account future diversion possibilities at downstream nodes based on real-time information not yet available at the time of decision-making. Based on the data collected from a driving simulator experiment and a matching PCbased experiment, a mixed Logit model with two latent classes, strategic and nonstrategic route choice, is specified and estimated. The estimates of the latent class probabilities show that a significant portion of route choice decisions are strategic and subjects can learn to make more strategic route choice as they have more experience with the decision scenarios. Non-parametric tests additionally show that network complexity adversely affects travelers’ strategic thinking ability in a driving simulator environment but not in a PC environment and a parallel driving task only affects strategic thinking ability in a difficult scenario but not a simple one. In addition, we find that people’s strategic thinking ability are influenced by their gender and driving experience (mileage) in the non-parametric analysis, but not in the modeling work. These findings suggest that a realistic route choice model with real-time traffic information should consider both strategic and non-strategic behavior, which vary with the characteristics of both the network and the driver.
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