This dissertation provides three essays. In the first essay, a model with two linguistic variables is built to demonstrate the joint effect of multiple linguistic variables in a dynamic modeling context. Triangular membership function is used to represent the linguistic variables and the joint effect is captured through fuzzy inference method. In this essay, the results obtained by employing fuzzy concepts are compared with the results that one would obtain using generic lookup functions. The second essay develops a system dynamics model by which policy makers can assess the impact of various travel demand management interventions within a metropolitan area and as a consequence understand the complex behavior of affected transportation-socioeconomic systems. This essay builds on a previously formulated approach where fuzzy concepts are used to represent five linguistic variables used in the model. We also compare the level of traffic congestion under the scenarios with and without traffic congestion pricing. The third essay is based on the second essay where different scenarios of the travel demand management policies are evaluated and analyzed. There are two parts in this essay. The first part addresses the construction of a Management Flight Simulator (MFS) that is used to do policy analysis for travel demand management policies. By using the Management Flight Simulator, the second part of the essay describes the evaluation of alternative travel demand management policies. In this research, we found that the revenue generated from congestion pricing does increase mass transit capacity even with the aging of mass transit capacity. However, in the short term traffic congestion is mitigated while in the long term the proposed travel demand management policy actually deteriorates the traffic situation. / Ph. D.

Our cities have been continually growing at an uncontrolled rate leading to the problem of trafficcongestion, which has discernable effects on all the aspects of sustainability, be it social,environmental or economical. This continual shift of increasing size of centre and decreasingsize of periphery poses huge sustainability challenge of meeting the consumption demands. Wepresently face the most unprecedented times in terms of the pace at which our natural resourcesare getting consumed. It is clear that replenishing some of these resources is totally out ofquestion. On the other side of the coin, the advances of human technology have provided itsgreatest gift of information & communication technology (ICT). Today we have access to datafrom any point of the world to anywhere. There is a growing need to use this data andinformation with a holistic view to build more Intelligent Transport Systems. In our paper wediscuss how the advent of ICT can have an impact on bringing a sustainable transportationsystem. The work is divided in two folds, by first understanding the direct role of ICT intransport sustainability and then observing the direct correlation between usage of ICT andtravel demand. The problems of traffic congestion and its solutions like congestion pricing haveexisted in practice since ages; the perspective which we add to it is the role of ICT in making itbetter. The greater perspective that is being researched here is at an absolute fundamental leveland takes us to the question if and how ICT can work on root level challenges, like findingmethods to have a better traceability without compromising on privacy, changing driverbehaviour patterns and stopping the expansion of centre & contraction of periphery.

The question of how to design a congestion pricing scheme is difficult to answer and involves a number of complex decisions. This thesis is devoted to the quantitative parts of designing a congestion pricing scheme with link tolls in an urban car traffic network. The problem involves finding the number of tolled links, the link toll locations and their corresponding toll level. The road users are modeled in a static framework, with elastic travel demand. Assuming the toll locations to be fixed, we recognize a level setting problem as to find toll levels which maximize the social surplus. A heuristic procedure based on sensitivity analysis is developed to solve this optimization problem. In the numerical examples the heuristic is shown to converge towards the optimum for cases when all links are tollable, and when only some links are tollable. We formulate a combined toll location and level setting problem as to find both toll locations and toll levels which maximize the net social surplus, which is the social surplus minus the cost of collecting the tolls. The collection cost is assumed to be given for each possible toll location, and to be independent of toll level and traffic flow. We develop a new heuristic method which is based on repeated solutions of an approximation to the combined toll location and level setting problem. Also, a known heuristic method for locating a fixed number of toll facilities is extended, to find the optimal number of facilities to locate. Both heuristics are evaluated on two small networks, where our approximation procedure shows the best results. Our approximation procedure is also employed on the Sioux Falls network. The result is compared with different judgmental closed cordon structures, and the solution suggested by our method clearly improves the net social surplus more than any of the judgmental cordons.

<p>The question of how to design a congestion pricing scheme is difficult to answer and involves a number of complex decisions. This thesis is devoted to the quantitative parts of designing a congestion pricing scheme with link tolls in an urban car traffic network. The problem involves finding the number of tolled links, the link toll locations and their corresponding toll level. The road users are modeled in a static framework, with elastic travel demand.</p><p>Assuming the toll locations to be fixed, we recognize a level setting problem as to find toll levels which maximize the social surplus. A heuristic procedure based on sensitivity analysis is developed to solve this optimization problem. In the numerical examples the heuristic is shown to converge towards the optimum for cases when all links are tollable, and when only some links are tollable.</p><p>We formulate a combined toll location and level setting problem as to find both toll locations and toll levels which maximize the net social surplus, which is the social surplus minus the cost of collecting the tolls. The collection cost is assumed to be given for each possible toll location, and to be independent of toll level and traffic flow. We develop a new heuristic method which is based on repeated solutions of an approximation to the combined toll location and level setting problem. Also, a known heuristic method for locating a fixed number of toll facilities is extended, to find the optimal number of facilities to locate. Both heuristics are evaluated on two small networks, where our approximation procedure shows the best results.</p><p>Our approximation procedure is also employed on the Sioux Falls network. The result is compared with different judgmental closed cordon structures, and the solution suggested by our method clearly improves the net social surplus more than any of the judgmental cordons.</p>

Autonomous vehicles (AVs) are a disruptive technology that is expected to vastly change the current transportation system. AV potential benefits in terms of safety, mobility, efficiency and other impacts types have been documented in the literature. AVs are expected to increase travel demand due to the enhanced ease of making trips and provision of mobility to people currently with travel-limiting disabilities. The potential increase in travel demand, with its attendant congestion, may probably be offset by the transportation network capacity increase due to the reduced operational headways between AVs. However, such capacity benefits can be fully realized only when AVs fully saturate the market, because operating at low headways may be unsafe for Human Driven Vehicles (HDVs). Thus, to promote AV ownership while capturing the capacity benefits of an AV-only traffic stream, the conversion of traditional lanes to AV-exclusive use is prescribed often. In the AV-exclusive lanes, the vehicles can operate at reduced headways and at higher speeds, sharply increasing throughput. However, the metric used frequently by researchers for AV-exclusive lane evaluation is the total system travel time. AV-exclusive lanes may appear to be beneficial in terms of total system travel time but may come at a cost of environmental protection and social equity, the other two elements of sustainable development. Appropriating HDV lanes for AV-exclusive use will cause congestion on HDV lanes thereby increasing their emissions. Further, the AVs benefits may be accompanied by increased cost of HDV travel, which raises questions about equity. This thesis therefore presents a sustainable AV-exclusive lane deployment strategy by formulating and solving a multicriteria bi-level optimization problem with equity-related constraints. Mathematically, the problem is described as a discrete network design problem. Recognizing the difficulty of solving this NIP hard problem, the thesis combines the active set method with heuristic conditionalities to improve computational efficiency. The thesis’s framework can be used by agencies for evaluation and decision support regarding AV-exclusive lane deployment in a manner that fosters long-term sustainability.

The purpose of this research dissertation is to compare the effects of using small, medium, and large cordon designs in road tolling on residential and commercial neighborhoods in Portland, Oregon. Changes in land use patterns are assessed by comparing the projected output of each cordon scenario to a "no toll" alternative in 2035. The performance of each cordon design is tested using two different prices ($1.65 and $8) and compared to a default scenario 25 years after the initial implementation in MetroScope's year 0, 2010. The following areas embedded within the cordon perimeter were considered in determining changes in land use: all the zones closest to the boundaries, the entire city of Portland, and the neighborhood towns surrounding Portland. Understanding the impact of choosing the "right" cordon size on economic development and residential location choices can be of utmost interest to lawmakers when they assess economic development policies. Unanswered questions remain regarding the impact a cordon scheme has on economic development and business location decisions, as well as its effect on the spatial pattern in the city. While studies on optimal toll pricing are abundant, there are very few studies that determine the optimal cordon location and size for a particular network. Accordingly, a critical question is whether cordon pricing will influence the centralization or decentralization of land use and affect jobs, population, and economic activities. The implementation of a cordon scheme is expected to affect areas both inside and outside of the designated perimeter and is further expected to contribute to changes that will affect land use. Existing studies have ignored land use effects and, instead, assume a monocentric city model. What sets this study apart is that instead of using a monocentric model to test the hypothetical cordon scenarios, the MetroScope model is used to predict changes in economy, demographics, and land use. The MetroScope model is one of only a few models that can assist in forecasting changes in both land use and prices. This study found primary evidence that the implementation of diverse sizes of cordon designs differently affect residential and non-residential land use patterns and trends.

Dynamic Traffic Assignment (DTA) is gaining wider acceptance among agencies and practitioners because it serves as a more realistic representation of real-world traffic phenomena than static traffic assignment. Many metropolitan planning organizations and transportation departments are beginning to utilize DTA to predict traffic flows within their networks when conducting traffic analysis or evaluating management measures. To analyze DTA-based optimization applications, it is critical to obtain the dual (or gradient) information as dual information can typically be employed as a search direction in algorithmic design. However, very limited number of approaches can be used to estimate network-wide dual information while maintaining the potential to scale. This dissertation investigates the theoretical/practical aspects of DTA-based dual approximation techniques and explores DTA applications in the context of various transportation models, such as transportation network design, off-line DTA capacity calibration and dynamic congestion pricing. Each of the later entities is formulated as bi-level programs. Transportation Network Design Problem (NDP) aims to determine the optimal network expansion policy under a given budget constraint. NDP is bi-level by nature and can be considered a static case of a Stackelberg game, in which transportation planners (leaders) attempt to optimize the overall transportation system while road users (followers) attempt to achieve their own maximal benefit. The first part of this dissertation attempts to study NDP by combining a decomposition-based algorithmic structure with dual variable approximation techniques derived from linear programming theory. One of the critical elements in considering any real-time traffic management strategy requires assessing network traffic dynamics. Traffic is inherently dynamic, since it features congestion patterns that evolve over time and queues that form and dissipate over a planning horizon. It is therefore imperative to calibrate the DTA model such that it can accurately reproduce field observations and avoid erroneous flow predictions when evaluating traffic management strategies. Satisfactory calibration of the DTA model is an onerous task due to the large number of variables that can be modified and the intensive computational resources required. In this dissertation, the off-line DTA capacity calibration problem is studied in an attempt to devise a systematic approach for effective model calibration. Congestion pricing has increasingly been seen as a powerful tool for both managing congestion and generating revenue for infrastructure maintenance and sustainable development. By carefully levying tolls on roadways, a more efficient and optimal network flow pattern can be generated. Furthermore, congestion pricing acts as an effective travel demand management strategy that reduces peak period vehicle trips by encouraging people to shift to more efficient modes such as transit. Recently, with the increase in the number of highway Build-Operate-Transfer (B-O-T) projects, tolling has been interpreted as an effective way to generate revenue to offset the construction and maintenance costs of infrastructure. To maximize the benefits of congestion pricing, a careful analysis based on dynamic traffic conditions has to be conducted before determining tolls, since sub-optimal tolls can significantly worsen the system performance. Combining a network-wide time-varying toll analysis together with an efficient solution-building approach will be one of the main contributions of this dissertation. The problems mentioned above are typically framed as bi-level programs, which pose considerable challenges in theory and as well as in application. Due to the non-convex solution space and inherent NP-complete complexity, a majority of recent research efforts have focused on tackling bi-level programs using meta-heuristics. These approaches allow for the efficient exploration of complex solution spaces and the identification of potential global optima. Accordingly, this dissertation also attempts to present and compare several meta-heuristics through extensive numerical experiments to determine the most effective and efficient meta-heuristic, as a means of better investigating realistic network scenarios. / text

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.

Managed lanes are a form of congestion pricing that use occupancy and toll payment requirements to utilize capacity more efficiently. How socio-spatial characteristics impact users’ travel behavior toward managed lanes is the main research question of this study. This research is a case study of the conversion of a High Occupancy Vehicle (HOV) lane to a High Occupancy Toll (HOT) lane, implemented in Atlanta I-85 on 2011. To minimize the cost and maximize the size of the collected data, an innovative and cost-effective modeling framework for socioeconomic analysis of managed lanes has been developed. Instead of surveys, this research is based on the observation of one and a half million license plates, matched to household locations, collected over a two-year study period. Purchased marketing data, which include detailed household socioeconomic characteristics, supplemented the household corridor usage information derived from license plate observations. Generalized linear models have been used to link users’ travel behavior to socioeconomic attributes. Furthermore, GIS raster analysis methods have been utilized to visualize and quantify the impact of the HOV-to-HOT conversion on the corridor commutershed. At the local level, this study conducted a comprehensive socio-spatial analysis of the Atlanta I-85 HOV to HOT conversion. At the general scale, this study enhances managed lanes’ travel demand models with respect to users’ characteristics and introduces a comprehensive modeling framework for the socioeconomic analysis of managed lanes. The methods developed through this research will inform future Traffic and Revenue Studies and help to better predict the socio-spatial characteristics of the target market.

This paper examines the issues of equity, as applicable to the HOV-to-HOT conversion project planned for the I-85 North corridor in the Metropolitan Atlanta Region. A review of literature is undertaken to describe the typology of transportation equity issues within the wider context of environmental justice, and to highlight socio-economic factors and local and national transportation funding factors that influence people's travel choices and their mobility and accessibility options. Demographic data on the I-85 corridor peak period commuters in Metropolitan Atlanta is analyzed, in addition to results of focus groups polling current Metropolitan Atlanta interstate commuters on the topic of managed lanes during 2008. The thesis makes a conclusion that a final decision about the equity impact of the I-85 HOV-to-HOT conversion is likely not possible without undertaking a Metropolitan area-wide analysis. Some of the equity findings that emerge indicate that there are no significant income differences between the the HOV lane users and general purpose lane I-85 commuters; that there are differences between median incomes of block groups represented by current I-85 commuters (both HOV lane users and general purpose lane users) and median incomes of block groups typical for the base geography; and that investing in Xpress bus service improvements would primarily serve those households with more vehicles than drivers, unless improvements to reverse commute options and feeder bus networks are made. The focus group findings suggest that current interstate highway users in Metropolitan Atlanta, originating in the suburbs, are generally accepting of the HOT concept and recognize the value of travel time savings.