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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.
241

Analysis of Traffic Accidents at Daytona Beach in Volusia County, State of Florida

Hajian, Mohammad Reza 01 April 1980 (has links) (PDF)
Anyone who has been tempted to cross a beach or walk along a beach is aware of the potential conflicts that can arise between pedestrians and vehicles. The competing use of the beach space results in conflicts between vehicles and pedestrians; many times the pedestrian's disregard for signed pedestrian safety provisions in the close vicinity and on the space allocated for car lanes results in avoidable conflicts. This report addresses the pedestrian and vehicle interaction at Daytona Beach in Volusia County of the State of Florida. This report has consolidated accident data for the period January 1, 1977 through July 22, 1979. The information was obtained through the Volusia county Department of Highway Safety and Motor Vehicles. Based on this information, suggestions have been given for continued improvement of the traffic accident situation at Daytona Beach.
242

A System Dynamics Model to Test Urban Transportation Policy Alternatives

Burtle, John Paul 01 January 1974 (has links) (PDF)
This study investigates the structure of urban transportation systems, the bases of commuter mode selection, and the effects of alternate transportation system management policies. The study was based on the hypothesis that changes in transportation system management policies are possible which will significantly increase the demand for public transportation in urban areas.
243

Using the Macroscopic Fundamental Diagram to Characterize the Traffic Flow in Urban Network

Ahmed, Istiak 04 February 2016 (has links)
Various theories have been proposed to describe vehicular traffic flow in cities on an aggregate level. This dissertation work shows that a number of MFDs exist in an urban network. The number of MFDs basically indicate the existence of different levels of service on different network routes. It also demonstrate that the modification of control strategy can optimize the signal timing plan for the links with high congestion and spillbacks. With the proposed control strategy, the location of points are shifted from lower MFDs to upper MFDs which means the congestion are reduced and the overall network traffic flow operation is improved. In this thesis, the emergency vehicle preemption (EVP) operation is also evaluated by using the MFDs. The concept of MFD can help to illustrate the effect on various types of roads due to EVP operation. The results show that the volume of links along the emergency route is increased and the volume of other links closed to the emergency route is decreased due to preemption. The researchers and practitioners can apply the proposed approach to identify the affected links and minimize the total network delay during EVP. / Master of Science
244

A location-allocation model and algorithm for optimally locating shelters to minimize evacuation times

Carter, Todd B. 08 September 2012 (has links)
Location â allocation models are designed to seek the concurrent location of a set of service facilities and an allocation scheme to satisfy the demands of a set of customers or users of a given system. If the location-allocation model is based on a graph-theoretic formulation, then the demand-fulfilling items will move from a designated origin or origins, through arcs and transshipment nodes, to a set of destinations selected by the model. It is suggested in this research effort that such a modeling structure may be employed to simulate transportation evacuation conditions that may arise in the case of a natural disaster, namely a hurricane. A nonlinear mixed integer mathematical program is formulated to route passengers in automobiles on paths in the transportation network, such that the endangered area is evacuated in the minimum amount of time. One heuristic and two exact, convergent, implicit enumeration algorithms based on the generalized Benders' decomposition method are presented. The algorithms are designed to exploit the inherent problem structure. Computational experience is provided against a set of realistic test problems formulated on the Virginia Beach network. Potential avenues for further research are also explored. / Master of Science
245

Influence of the city geometric features on the two fluid model parameters

Ayadh, Mohammed Thabet 14 November 2012 (has links)
The traffic flow in an urban street network is a complicated system which involves many variables. Some of these variables relate to the network's geometric features; some of these variables reflect the characteristics of the vehicles, drivers and pedestrians using the network. The Two Fluid Model was introduced to help evaluate the quality of traffic service in urban street networks. The model parameters, T<sub>m</sub> and n, are used as a scale to compare traffic quality in two or more urban street networks. It is known that the higher the values of the two parameters in a network, the lower the quality of the network's traffic service. This report presents material which may be used to predict the correlation between the Two Fluid Model parameters and the geometric features of a specific street network. The Two Fluid Model parameters will be used as dependent variables in this analysis. Seven network geometric features were selected to be used as independent variables. Using linear regression techniques, the variables will be analyzed to formulate two models. One model will explain the relationship between Tm and corresponding geometric features; the other model will explain the relationship between T<sub>m</sub> and its corresponding features. A basic understanding of these two models will allow traffic engineers to develop strategies and/or network changes to improve traffic service in a city's street network. This will especially help networks still in the planning and/or design stage. Because the trip time per unit distance, T, is an important traffic variable for both the Two Fluid Model and in fuel consumption models, portions of this report concentrated on establishing a relation between the two models. / Master of Science
246

Development of a methodology to interface transportation planning and traffic simulation

Raghunathan, Ranga 16 December 2009 (has links)
The purpose of this research is to develop a methodology to interface transportation planning and traffic simulation. Differences in representations of planning and traffic networks prohibits planners and engineers from sharing the input data for the same area being studied. Therefore the planning data need to be utilized to create data that the traffic engineers can use for traffic simulation, thus avoiding duplication of effort to collect data for the two purposes. The methodology developed specifically for the Urban Transportation Planning Software (UTPS) and Traffic Simulation Software (TRAF), can be modified to interface planning and simulation performed by other software as well. The methodology is demonstrated using a typical urban town network. / Master of Science
247

A dynamic traffic simulation/assignment model in the context of Advanced Driver Information Systems

Ozbay, Kaan 22 October 2009 (has links)
Growing congestion problems of many metropolitan areas which cause excessive traffic delay, instability of travel time generated the need for the development of an Intelligent Vehicle Highway System (IVHS) program that is capable of making significant improvements in mobility, highway safety, and productivity on highways and urban streets. The success of such real time control system highly depends on the new methods that address dynamic traffic assignment. Thus there is an urgent need for an effective dynamic assignment model. The main objective of this research is to emphasize the importance of dynamic traffic assignment for Advanced Driver Information Systems (ADIS) which is one of the major components of IVHS and to present a practical traffic assignment model that is capable of running in real time and which can accurately predict link travel times, queue build up, and network performance. DYNTRAS (DYNamic Traffic Simulation Assignment), a simulation /assignment model is developed. The model uses an incremental loop that assigns a portion of the Origin-Destination matrix, and simulates the movement of the vehicles. Then, it updates travel times and assigns an additional portion of the O-D matrix. In contrast to traditional traffic assignment models like "capacity restraint" and “incremental assignment" techniques that do not consider time dimension, DYNTRAS incorporates time as a third dimension by keeping track of the vehicle movements in time. As a result, it is capable of predicting time-dynamic impacts of congestion and effects of diverted traffic on traffic flow more realistically. The model is applied to a test network. “Several experimental factors are varied to test the sensitivity of the model. The results obtained are presented and general conclusions are derived. The differences between dynamic and static traffic assignment results are also discussed by considering results obtained from both methods. The model needs to be calibrated using real traffic data. According to the results obtained, it needs to be validated. In addition, its long computation time should be reduced to be able to use it for real time applications. / Master of Science
248

The Effects of Altered Traffic Signs upon Vehicular Driving Modes and Consequent Fuel Conservation and Environmental Benefits, as Measured by Vehicular Noise-imprints

Pfarrer, Mark Daniel 01 January 1976 (has links) (PDF)
The hypothesis is that the recorded noise-imprints of a vehicle at an intersection can be used to identify and accurately time the driving modes of deceleration, idle, slow cruise, and acceleration. This is proven by analyzing and comparing noise-imprints of vehicles at an uncontrolled intersection marked first with a "stop" sign, and then by a "yield" and an experimental "dead slow" sign. By relating the duration of each driving mode to known relations, the overall efficiency of an intersection can be characterized. A new technique for studying various types of traffic conditions at intersections is the result. Initial noise-imprint analysis and comparison shows that a "yield" sign is to be preferred over a "stop" sign to decrease travel time, air pollution emissions, gasoline consumption, and wear-and-tear on the car. The experimental "dead slow" sign is used as a demonstration of the noise-imprint technique upon an unknown situation. The efficiency of a "dead slow" sign proved to be less than that of a "yield" sign, but still greater than that of a "stop" sign.
249

Automated collection of vehicular delay data at intersections

Legere, Jay Francis January 1983 (has links)
Most current methods used for the estimation of vehicular delay at intersections involve some form of manual data collection. These methods rely on statistical correlation to improve the accuracy of the delay estimates. In addition, most require significant data collection and reduction efforts. This work presents the theory, design, and operation of a microprocessor-based system for the collection of vehicular delay data at intersections. The hardware design is described in detail including schematic diagrams of the microprocessor system and the associated interface circuitry. Documented software listings and flowcharts are provided as well as a description of the data collection and reduction processes. A benefit/cost analysis was made based on the construction and operation of a prototype system. The system performance was evaluated both in the lab and through analysis of data collected in the field. Recommendations for further development of the device are presented as well as applications of the microprocessor to other forms of transportation and traffic engineering data. / M.S.
250

Improving Dilemma Zone Protection Control Issues at Signalized Intersection Using a Web-Game

Kasaraneni, Yatish 05 November 2009 (has links)
Web games provide a platform for creative instructional activities that can capture the students' attention towards the course. These games can be used to emulate the realistic situations which can be used as effective lab experiments that could give the students a hands-on experience using real world scenarios. This thesis presents an innovative web-based game developed for the demonstration of the driver-behavior at signalized intersections that can be used as a supplementary tool for the Transportation Engineering course. The game format is carefully designed to supplement the understanding of the class learning material through a fun environment. It was designed to be widely accessible through the internet and have an attractive user interface and was improved from the feedback obtained from the pilot study. The game is programmed on the .NET Framework using the Microsoft Visual C# as a core programming language, ASP to develop the web interface, and Microsoft Access as the databases for the program. The thesis also provides a methodological framework for collecting data about student engagement in a course and in particular presents the data collection procedure used in Transportation Engineering Course (CEE 4609). The collected data was analyzed to find the student engagement in the course after the introduction of the game. The thesis gives the conclusions drawn from the research with insights into possible drawbacks and scope for future improvements. / Master of Science

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