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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.
21

VERSO - A SYSTEM TO ADAPT AUTOMOBILES IN EMERGING NATIONS

CONTRERAS, GIOVANNI Jesue 28 September 2005 (has links)
No description available.
22

Travel Behavior of a Mid-West College Community: A case Study of the University of Toledo

Akter, Taslima, Akter January 2016 (has links)
No description available.
23

Cycling towards Sustainability: the path runs through Malmö

Sabaini, Francesco January 2013 (has links)
Set in the sustainable urban development context, the purpose of this work is to depict cycling as a powerful mean to improve social, environmental and economic conditions in our cities. Moving from a qualitative analysis, the work has been conducted by analyzing a series of initiatives that take place in Malmö (Sweden) aimed at raising cycling awareness and practices. The city serves as a model for discussing sustainable development in general.The results show that, even when practicing good cycling policies, public authorities need to adopt broader and more inclusive approaches in order to avoid inconsistencies and divergences. In the diversity of urban cycling dynamics, learning processes and social innovation thrive: if on one hand they help to fill gaps left by public policies, helping to overcome hindrances in cycling promotion, on the other they also set the possibility for a progress in economic and social urban life.
24

Modelling Annual Bike Share Ridership at Hubs with Bike Share Expansion in Mind

Choi, Geun Hyung (Jayden) January 2020 (has links)
Public bike share systems have been recognized as an effective way to promote active and sustainable public transportation. With the health benefits of bike share becoming better understood, North American cities have continued to invest in cycling infrastructure and impose new policies to not only encourage the usage of bike share systems but also expand their operations to new cities. The city of Hamilton, Ontario, implemented its own bike share system in March 2015. Using the system’s global positioning system (GPS) data for annually aggregated trip departures, arrivals, and totals in 2017, this research explores various environment factors that have an impact on users’ bike share usage at hub level. Nine predictive linear regression models were developed for three different scenarios depending on the type of hubs and members for trip departures, arrivals, and totals. In terms of variance explained across the core service area, the models suggested the main factors that attract users were distance to McMaster University and the number of racks available at hubs. Furthermore, the working population and distance to the Central Business District and the closest bike lane in the immediate vicinity (200 m buffer) also played important roles as contributing factors. Based on the primary predictors, this research takes one step further and estimates potential trips at candidate sites to inform future expansion of public bike share system. The candidate locations were created on appropriate land uses by applying a continuous surface of regularly shaped cells, a hexagonal tessellation, on the area of interest. The estimated potential usage at candidate sites demonstrated that the east part of the city should be targeted for future bike share expansion. / Dissertation / Master of Science (MSc)
25

Integrated Multi-Criteria Signal Timing Design for Sustainable Traffic Operations

Guo, Rui 18 March 2015 (has links)
Traffic signal systems serve as one of the most powerful control tools in improving the efficiency of surface transportation travel. Traffic operations on arterial roads are particularly complex because of traffic interruptions caused by signalized intersections along the corridor. This dissertation research presents a systematic framework of integrated traffic control in an attempt to break down the complexities into several simpler sub-problems such as pattern recognition, environment-mobility relationships and multi-objective optimization for multi-criterial signal timing design. The overall goal of this dissertation is to develop signal timing plans, including a day plan schedule, cycle length parameters, splits and offsets, which are suitable for real traffic conditions with consideration of multi-criterial performance of the surface transportation system. To this end, the specific objectives are to: (1) identify appropriate time-of-day breakpoints and intervals to accommodate traffic pattern variations for day plan schedule of signal timing; (2) explore the relationship between environmental outcomes (e.g., emissions) from emission estimators and mobility measures (e.g., delay and stops) for different types of intersections; (3) optimize signal timing parameters for multi-criteria objectives (e.g., minimizing vehicular delay, number of stops, marginal costs of emissions and total costs), with the comparison of performance metrics for different objectives, at the intersection level; (4) optimize arterial offsets for different objectives at the arterial level and compare the performance metrics of different objectives to recommend suitable objectives for integrated multi-criteria signal timing design in arterial traffic operations. An extensive review of the literature, which covers existing tools, traffic patterns, traffic control with environmental concerns, and related optimization methods, shows that both opportunities and challenges have emerged for multi-criteria traffic signal timing design. These opportunities include large quantities of traffic condition data collected by system detectors or non-intrusive data collection platforms as well as powerful tools for microscopic traffic modeling and instantaneous emission estimation. The challenge is how to effectively deal with these big data, either from field collection or detailed simulation, and provide useful information for decision makers in practice. Methodologically, there's a tradeoff between the accuracy of objective function values and the computational efficiency of simulation and optimization. To address this need, in this dissertation, traffic signal timing design that systematically enables the use of integrated data and models are investigated and analyzed in the four steps/studies. The technology of identifying time-of-day breakpoints in the first study shows a mathematical way to classify dynamic traffic patterns by understanding dynamic traffic features and instabilities at a macroscopic level on arterials. Given the limitations of using built-in emissions modules within current traffic simulation and signal optimization tools, the metamodeling-based approach presented in the second study makes a methodological contribution. The findings of the second study on environment-mobility relationships set up the base for extensive application of two-stage optimization in the third and fourth studies for sustainable traffic operations and management. The comparison of outputs from an advanced estimator with those from the current tool also addresses improving the emissions module for more accurate analysis (e.g., benefit-cost analysis) in practical signal retiming projects. The third study shows that there are tradeoffs between minimizing delay and minimizing marginal costs of emissions. When total cost (including cost of delay, fuel consumption and emissions) is set as a single objective function, that objective clears the way for relatively reliable results for all the aspects. In the fourth study, the improvements in marginal cost of emissions and total cost by dynamic programming procedure are obvious, which indicates the effectiveness of using total link cost as an objective at the corridor level. In summary, this dissertation advocates a sustainable traffic control system by simultaneously considering travel time, fuel consumption and emissions. The outcomes of this integrated multi-criteria signal timing design can be easily implemented by traffic operators in their daily life of retiming signal timing.
26

Assessment Of Scenarios For Sustainable Transportation At Metu Campus

Altintasi, Oruc 01 January 2013 (has links) (PDF)
Sustainable transportation aims encouragement of non-motorized (pedestrian and bicyclist) and shared-ride transportation modes instead of car-dependent travels. This is important for university campuses, as they have better chance to implement such policies in a rather controlled traffic network, and can set an example to other communities. Most of sustainable campus transportation programs boil down to reduction of car-based emission cost of campus mobility, which is always the first step in developing more sustainable transportation policies. Middle East Technical University (METU), Ankara has a large campus area and a population over 30,000 people. To develop sustainable campus transportation policies, it was important to quantify the current levels of mobility and vehicle emissions within the campus, which was the main motivation behind this study. This required determination of i) campus origin-destination matrix, ii) in-campus vehicle-km-travelled (vehicle-km), and iii) carbon emissions. Travel data obtained from different sources, including the gate entry with RFID systems enabled analysis of different user groups, such as academic and administrative personnel and students, separately. The traffic simulations were prepared in PTV VISUM, which provided both speed and vehicle-km values for road segments, and could represent multi-user group demand matrices in a single traffic assignment. Based on the base case mobility and emission values, more sustainable campus transportation policies were simulated in PTV VISUM, and assessed in terms of carbon emission impacts. Discouraging of private car usage by students seemed the first and simplest action.
27

Incorporating Sustainability into Transportation Planning and Decision Making: Definitions, Performance Measures, and Evaluation

Jeon, Mihyeon Christy 14 November 2007 (has links)
An increasing number of agencies have begun to define sustainability for transportation systems and are taking steps to incorporate the concept into the regional transportation planning process. Planning for sustainable transportation systems should at the very least incorporate their broader impacts on system effectiveness, environmental integrity, economic development, and the social quality of life. This study reviews definitions, performance measures, and evaluation methodologies for transportation system sustainability and demonstrates a framework for incorporating sustainability considerations in transportation planning and decision making. Through a case study using data from the Atlanta Metropolitan Region, the study evaluates competing transportation and land use plans based on a broad range of sustainability parameters using relevant spatial and environmental analyses. A multiple criteria decision making (MCDM) method enables the aggregation of individual performance measures into four basic indexes and further into a composite sustainability index based on regional goals and priorities. The value of the indexes lies in their ability to capture the multidimensional nature of sustainability as well as important tradeoffs among the potentially conflicting decision criteria. A decision support tool is proposed to visualize dominance and tradeoffs when evaluating alternatives and to effectively reflect changing regional priorities over time. The proposed framework should help decision makers with incorporating sustainability considerations into transportation planning as well as identifying superior plans for predetermined objectives.
28

Analyzing the impacts of last mile mobility and studying the implementation of alternative vehicles in Swedish cities.

Mota Lozano, David January 2022 (has links)
The growing population of cities and the rise of e-commerce are increasing the transportation of both goods and people. This can generate problems such as traffic jams, increased pollution, and lower living standards for citizens. To reduce the negative impacts, a change in last mile mobility could be made, replacing traditional combustion vehicles with electric ones or, ideally, with bikes and cargo bikes.  This thesis examines the case of the Swedish cities of Gävle and Uppsala, trying to explain how the last mile affects the lives of their inhabitants, if and why electric vehicles and cargo bikes are implemented (or not), and how authorities can promote their use. For this purpose, after a literature review, some questions were developed, and seven city managers were interviewed: five from Gävle and two from Uppsala.  The study shows that city managers are aware of the impacts that the last mile, and mobility in general, has on its inhabitants, and of the need for a shift towards a more sustainable mobility. Despite this awareness, policy makers are not doing everything possible to accelerate the transition. According to city managers, both the public and private sector advocate more for a change of energy source (from combustion to electric vehicles) rather than a model change using bikes. In addition, the study shows the opportunities that the new model based on non-traditional vehicles can offer and the barriers that prevent its implementation. Finally, different measures that could make cities more sustainable are proposed.
29

Sustainability Analysis Of Intelligent Transportation Systems

Ercan, Tolga 01 January 2013 (has links)
Commuters in urban areas suffer from traffic congestion on a daily basis. The increasing number of vehicles and vehicle miles traveled (VMT) are exacerbating this congested roadway problem for society. Although literature contains numerous studies that strive to propose solutions to this congestion problem, the problem is still prevalent today. Traffic congestion problem affects society’s quality of life socially, economically, and environmentally. In order to alleviate the unsustainable impacts of the congested roadway problem, Intelligent Transportation Systems (ITS) has been utilized to improve sustainable transportation systems in the world. The purpose of this thesis is to analyze the sustainable impacts and performance of the utilization of ITS in the United States. This thesis advances the body of knowledge of sustainability impacts of ITS related congestion relief through a triple bottom line (TBL) evaluation in the United States. TBL impacts analyze from a holistic perspective, rather than considering only the direct economic benefits. A critical approach to this research was to include both the direct and the indirect environmental and socio-economic impacts associated with the chain of supply paths of traffic congestion relief. To accomplish this aim, net benefits of ITS implementations are analyzed in 101 cities in the United States. In addition to the state level results, seven metropolitan cities in Florida are investigated in detail among these 101 cities. For instance, the results of this study indicated that Florida saved 1.38 E+05 tons of greenhouse gas emissions (tons of carbon dioxide equivalent), $420 million of annual delay reduction costs, and $17.2 million of net fuel-based costs. Furthermore, to quantify the relative impact and sustainability performance of different ITS technologies, several ITS solutions are analyzed in terms of total costs (initial and operation & maintenance costs) and benefits (value of time, emissions, and safety). To account for the uncertainty in benefit and cost ii analyses, a fuzzy-data envelopment analysis (DEA) methodology is utilized instead of the traditional DEA approach for sustainability performance analysis. The results using the fuzzy-DEA approach indicate that some of the ITS investments are not efficient compared to other investments where as all of them are highly effective investments in terms of the cost/benefit ratios approach. The TBL results of this study provide more comprehensive picture of socio-economic benefits which include the negative and indirect indicators and environmental benefits for ITS related congestion relief. In addition, sustainability performance comparisons and TBL analysis of ITS investments contained encouraging results to support decision makers to pursue ITS projects in the future.
30

Can Institutional Reforms Promote Sustainable Planning? Integrating Regional Transportation and Land Use in Toronto and Chicago (2001-2014)

Tremblay-Racicot, Fanny Rose January 2015 (has links)
Although governments have implemented several reforms to better integrate or coordinate regional transportation and land use decisions, little is known about the effects of new institutional designs on planning and development outcomes. This study compares the effects of two different types of institutional reforms on the planning process, transportation investments and land use decisions, while assessing their characteristics in terms of accountability, democracy, and effectiveness. Using semi-structured interviews, planning documents, as well as transportation spending and land use decisions, this longitudinal, comparative case study assesses the effects of the centralized, regulatory framework implemented in Toronto in 2005-2006, to the collaborative governance framework adopted in Chicago in 2005. Although each institutional design features different sets of constraints and opportunities, both reforms improved the planning process by establishing a renewed commitment to the exercise of regional planning. However, their impact on transportation investments was limited because the allocation of transportation funds is still primarily controlled by the province and the state governments who continue to control the purse strings and allocate money to advance their own political agendas. Both cases also show how difficult it is to increase densities and curb urban sprawl because local land uses, zoning and development approvals remain the prerogative of local governments and a function of locational preferences of individuals and corporations, which are contingent upon the market and shaped by global economic forces. Besides stronger regional institutions, the evidence presented in this study calls for new political strategies that address the fiscalization of land use and that offer financial incentives for the adoption of smart growth policies. / Urban Studies

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