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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.
331

Investigation of using radar augmented transit buses as arterial travel time probes

Thornton, Douglas Anthony 02 September 2009 (has links)
No description available.
332

Modeling Transit Vehicle Travel Time Components for Use in Transit Applications

Alhadidi, Taqwa Ibrahim 22 June 2020 (has links)
Traffic congestion has continued to grow as a result of urbanization, which is associated with an increase in car ownership. As a way to improve the efficiency of the transportation system, emerging technologies including Connected Automated Vehicles (CAVs), loop detectors, Advanced Traveler Information Systems (ATISs), and Advanced Public Transportation Systems (APTSs) are being deployed. One of the successful techniques that has demonstrated benefits for system users, operators and agencies is Transit Signal Priority (TSP). TSP favors transit vehicles in the allocation of green times at traffic signals. A successful deployment of TSP depends on different factors including the prediction of various components of transit vehicle travel times to predict when a vehicle would arrive at a traffic signal. Current TSP state-of-the-art and state-of-practice disregards the impact of bus stops, transit vehicle characteristics, driver, and the prevailing traffic conditions on the predicted arrival time of transit vehicles at traffic signals. Considering these factors is important the success of TSP hinges on the ability to predict transit vehicle arrival times at traffic signals in order to provide these vehicles with priority service. The main contribution of this research effort relates to the modeling of the various components of transit vehicle travel times. This model explicitly captures the impact of passengers, drivers and vehicle characteristics on transit vehicle travel times thus providing better models for use in various transit applications, including TSP. Furthermore, the thesis presents a comprehensive understanding of the determinants of each travel time component. In essence, the determinants of each component, the stochasticity in these determinants and the correlation between them are explicitly modeled and captured. To achieve its contribution, the study starts by improving the current state-of-the-art and state-of-practice transit vehicle boarding/alighting (BA) models by explicitly accounting for the different factors that impact BA times while ensuring a relatively generalized formulation. Current formulations are specific for the localities and bus configurations that they were developed for. Alternatively, the proposed BA time model is independent of the transit vehicle capacity and transit vehicle configuration (except for the fact that it is only valid for two-door buses – a separate door for alighting and boarding the bus) and accounts for the number of on-board passengers, boarding and alighting passengers. The model also captures the stochasticity and the correlation between the model coefficients with minimum computational requirements. Next the model was extended to capture the bus driver and vehicle impacts on the transit vehicle delay in the vicinity of bus stops, using a vehicle kinematics model with maximum speed and acceleration constraints to model the acceleration/deceleration delay. The validation of the model was done using field data that cover different driving conditions. Results of this work found that the proposed formulation successfully integrated the human and vehicle characteristics component in the model and that the new formulation improves the estimation of the total delay that transit vehicles experience near bus stops. Finally, the model was extended to estimate the time required to merge into the adjacent lane and the time required to traverse a queue upstream of a traffic signal. The final part of this study models the bus arrival time at traffic signal using shockwave and prediction model in a connected environment. This section aims to model the transit vehicle arrival time at traffic signal considering the impact of signal timing and the prevailing traffic conditions. In summary, the proposed model overcomes the current state-of-the-art models in the following ways: 1) it accounts for the vehicle capacity and the number of on-board passengers on bus BA times, 2) it captures the stochasticity in the bus stop demand and the associated BA times, 3) it captures the impact of the traffic in modeling the delay at a bus stop , 4) it incorporates the driver and vehicle impact by modeling the acceleration and deceleration time, and 5) it uses shockwave analysis to estimate bus arrival times through the use of emerging technology data. Through statistical modeling and evaluation using field and simulated data, the model overcomes the current state-of practice and state-of art transit vehicle arrival time models. / Doctor of Philosophy / Traffic congestion grows rapidly causing increment in travel time, reducing travel time reliability, and reducing the number of public transportation riders. Using the Advanced Public Transportation Systems (APTS) technology with Advanced Traveler Information Systems (ATISs) helps in improving transportation network travel time by providing real-time travel information. One of the successful techniques that has demonstrated benefits for system users, operators and agencies is Transit Signal Priority (TSP). A successful deployment of TSP depends on different factors including the prediction of various components of transit vehicle travel times to predict when a vehicle would arrive at a traffic signal. Current TSP state-of-the-art and state-of-practice disregards the impact of bus stops, transit vehicle characteristics, driver, and the prevailing traffic conditions on the predicted arrival time of transit vehicles at traffic signals. The difficulty of modeling the various determinants of the transit vehicle travel time as explicit variables rather than include some of them are implicitly modeled due to two main reasons. First, there are various significant factors affecting estimating the transit vehicle arrival time including; the passenger demand at bus stop, driver characteristics, vehicle characteristics and the adjacent prevailing traffic conditions. Second, the stochasticity and the fluctuation nature of each variables as they differ spatiotemporally. The research presented in this thesis provides a comprehensive investigation of the determinants of different transit vehicle travel time components of the transit vehicle arrival time at traffic signal leading to a better implementing of TSP. This study was initiated due to the noticeable overlooking of the different factors including human and vehicle behavior in the current state-of-practice and state-of-art which, as a result, fails to capture and incorporate the impact of these components on the implementing of TSP.
333

Modeling Diesel Bus Fuel Consumption and Dynamically Optimizing Bus Scheduling Efficiency

Edwardes, William Andrew 11 August 2014 (has links)
There are currently very few models that estimate diesel and hybrid bus fuel consumption levels. Those that are available either require significant dynamometer data gathering to calibrate the model parameters and also produce a bang-bang control system (optimum control entails maximum throttle and braking input). This thesis extends the Virginia Tech Comprehensive Power-Based Fuel Consumption Model (VT-CPFM) to model diesel buses and develops an application for it. A procedure is developed to calibrate the bus parameters using publicly available data from the Altoona Bus Research and Testing Center. In addition, calibration is also made using in-field bus fuel consumption data. The research presented in this thesis calibrates model parameters for a total of 10 standard diesel buses and 3 hybrid buses from Altoona and 10 buses from Blacksburg Transit. In the case of the Altoona data, the VT-CPFM estimated fuel consumption levels on the Orange County bus cycle dynamometer test produce an average error of 4.7%. The estimation error is less than 6% for all but two buses with a maximum error of 10.66% for one hybrid bus. The VT-CPFM is also validated using on-road fuel consumption measurements that are derived by creating drive cycles from acceleration information producing an average estimation error of 22%. These higher errors are attributed to the errors associated with constructing the in-field drive cycles given that they are not available. In the case of the Blacksburg Transit buses, the calibrated parameters produce a low sum of mean squared error, less than 0.002, and a coefficient of determination greater than 0.93. Finally an application of the VT-CPFM is presented in the form of a dynamic bus scheduling algorithm. / Master of Science
334

Demand-responsive transit : problems and possibilities.

Ewing, Reid Harris. January 1978 (has links)
Thesis: Ph. D., Massachusetts Institute of Technology, Department of Civil Engineering, 1978 / Bibliography: leaves 255-264. / Ph. D. / Ph. D. Massachusetts Institute of Technology, Department of Civil Engineering
335

The Dallas Transit Company: Transition from Private to Public Ownership

Duke, Jimmy D. 08 1900 (has links)
Dallas, Texas, faces transportation problems common to all metropolitan areas. This thesis will examine the effort of the City of Dallas to find a solution to a particular transportation problem, that of public transit. Events leading to the city's purchase of a privately owned transit company and problems encountered during the year after the purchase will be primarily considered in this thesis. The basic methodology consisted of interviews with persons directly connected with the transit operation, including city administrators, City Council members, and transit board members. A newspaper reporter, closely associated with the problem from beginning to end, gave an objective, eye-witness account of the situation. Additionally, newspaper accounts of the transition from private to public transit ownership provided a useful chronology, and letters and public documents supplied other information. City leaders realized that a good transit system was a vital part of a balanced Metropolitan program of transportation. Because the privately owned transit company was not providing adequate bus service, the city found it desirable to assume public ownership of the transit operation through purchase of the Dallas Transit Company in January, 1964.
336

Selling transit: perception, participation, and the politics of transit in Kansas City, Missouri

Wood, James Patrick January 1900 (has links)
Master of Regional and Community Planning / Department of Landscape Architecture/Regional and Community Planning / Huston John Gibson / Informed and robust stakeholder participation in the transit-planning process gives residents and communities a remarkable opportunity to take ownership of the shaping of their city’s future form and function, and allows planners to design transit networks that serve the full range of citizen needs. Therefore, the degree to which citizens are permitted to participate in the formation of a city’s transit plan has a significant influence on both its final design and its subsequent adoption by civic and political leaders. Concurrent with the influence of citizen input is the role of political strategy, since many urban transit plans must meet voter approval and a poorly-run political campaign can sink even the most substantial of transit plans. In seeking to analyze both the role of public participation and the role of campaign strategy, this study employs descriptive historical research and stakeholder surveys to assess the impact and perceived importance of inclusive design practices, as well as the political impact of a transit campaign’s general strategy, on the voter approval of transit-related ballot initiatives in Kansas City, Missouri. There are two central implications of this project. One is that the failure of transportation planners and civic activists in Kansas City to accommodate the wishes and input of diverse groups of residents and community leaders in the planning process has led to repeated defeats whenever said plans are presented to Kansas City voters for approval. The other is that urban politics and campaign strategies play a larger role in selling transit proposals than many leading figures in Kansas City have realized, and that the city’s unique political and geographic structure requires a more nuanced and technologically-diverse approach to voter persuasion than has been applied thus far. It can be theorized that reversing both of these trends will increase the likelihood of future voter approval of transportation initiatives. In addition to a political and historical analysis of transit in Kansas City, this study seeks to examine whether deliberate public participation in the transportation planning process has a direct impact on citizen support for transportation-related ballot initiatives in Kansas City.
337

Analýza celních režimů v EU se zaměřením na režim tranzitu / The analysis of customs procedures in the EU with the focus on transit

Lukavská, Dana January 2008 (has links)
The thesis responds to the changes in customs procedures which Czech companies had to face after the Czech republic was joined to the customs territory of the EU. The first part of the thesis provides the basic characteristic of individual customs procedures and it is focused on the area of customs operations. The following sections concentrate on the issue of "transit" customs procedure. The scope of the thesis is a general approach of the realisation of international transport in transit. It demonstrates the most important changes which were caused by the membership of the Czech Republic in the EU. The thesis emhasizes Community transit, Common transit betweeen the Community and the EFTA countries and the carriage of goods based on the customs documents TIR a ATA. Due to its importance for facilitating international trade a special attention is given to the TIR customs transit system.
338

Riding Red Ink: Public Ownership of Mass Transit in Indianapolis

Wilhite, Ryan Daniel January 2011 (has links)
**Note** During the research process, IndyGo donated some of the resources cited within this paper to the Indiana Historical Society. That collection has not been archived yet. Further, IndyGo may have placed other documents (created during the time of public ownership) in the Indiana State Archives or the Indiana State Library. / Indiana University-Purdue University Indianapolis (IUPUI) / Today, most urban mass transit providers are publicly owned. Just a few decades ago, and for a majority of the history of mass transit, private owners provided transportation for communities. The decline of private ownership in Indianapolis resulted in transit crisis that pitted private owners against local government, riders and community groups. Advocates lambasted the private owners for their profit-first tactics, pointing to the dividends gained by the private owners. These owners, the Midland Transportation Corporation, also owned the mass transit companies in Milwaukee, Wisconsin and Louisville, Kentucky. Indianapolis politicians, residents and newspapers, all firmly conservative, hoped private owners could continue to operate Indianapolis Transit Systems without public assistance. The imminent failure prompted a discussion of the future of transportation in the city of Indianapolis. Community groups hoped the new public corporation would increase service for Indianapolis and not continue the skeleton system managed by the private owners. A storm of uncontrollable events prevented the robust expansion of the new public corporation and its lack of funding resulted in a continuing decline of service, much akin to the private owners that were abhorred by transit riders. Public ownership in Indianapolis revealed the importance of public ownership in the historiography of mass transportation and urban history. The regional investigation of Midland Transportation confirmed the notion of transit as a unique industry, both in its industrial relations and influence of the locality. The basic rationale for public ownership in Indianapolis would be the most important: the provision of public transportation for those unable to afford private transportation to obtain necessary services.
339

Measuring low stress bike access to MARTA

Bearn, Cary Briscoe 07 January 2016 (has links)
Level of Traffic Stress (LTS) is a bicycle quality of service measure originally developed by the Mineta Transportation Institute (MTI) that categorizes road infrastructure into four levels based on amount of traffic stress perceived by a bicyclist. The concept builds on research indicating that bicyclists can be grouped based on their comfort level. Riders identifying as strong and fearless as well as enthused and confident bicyclists represent most of the current users of the bicycle network across the US. However, there is a large group of cautious and concerned bicyclists that might be more likely to bike if the bicycle infrastructure were less stressful. This research applies the LTS methodology to quantify low stress bicycle access around the West End, Oakland City, and Lakewood/Ft. McPherson (Metropolitan Atlanta Rapid Transit Authority) MARTA rail stations. The Equitable Transit Oriented Development (TOD) typology analysis conducted by Reconnecting America identified these station areas as highly vulnerable with lagging markets. Additional analysis compares the existing low stress network, improved low stress networks, and the entire (low and high stress) bike network. Ultimately this work can serve as a model for both transportation planners interested in improving bike access both in general and specifically to transit.
340

Increasing the usage of demand-response transit in rural Kansas

Geiger, Brian Christopher January 1900 (has links)
Master of Science / Department of Civil Engineering / Sunanda Dissanayake / Public transportation in rural America has existed for decades. Its providers are challenged with low populations and long distances in rural areas. Many of these rural transit providers have been in existence for many years, but ridership still remains low. These providers usually operate in a demand-response format, as opposed to large cities, where buses run on fixed routes. This research was conducted to see if any type of service improvements or enhancements could be found in order to increase ridership of demand-response transit service in rural Kansas. In order to determine if ridership of public transportation in rural Kansas can be increased, customer satisfaction surveys were conducted. One survey was distributed to current riders of demand-response systems, one survey distributed to non-riders of public transportation, and the last survey given to providers to obtain basic system information throughout Kansas. Ridership is significantly skewed toward the elderly, disabled, and those who either choose not to drive or are unable to drive. Those who do not fall into one of these three categories often do not use public transportation in rural areas. For most of the riders, public transportation is their only reliable method of mobility as they are transit dependent. Only 35% of the riders had a personal vehicle they could use to make the trip had public transportation not been available. Riders of demand-response transit systems in rural Kansas are pleased with the service provided as a whole. Non-riders are ambivalent toward demand-response transit service. They appreciate the fact that in many cases general public transportation service exist, but they are also generally unwilling to use it themselves. These are typically choice riders, and are unlikely to switch to demand-response transit due to their other mobility options. It was found that the more vehicles a person has access to in their household, the less knowledge they have about public transportation in their area. These people are content to use the vehicles they have, because it is more convenient than using public transportation in rural Kansas. Improvements to the provider’s system, like extending operating hours and days, along with implementing GIS-assisted scheduling may bring higher ridership. However, this may only increase the number of rides by the same current riders with few new riders grained. Increasing the usage of demand response ridership will continue to be a challenge in the future with the increasing number of elderly in the years to come.

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