The objective of this study was to provide an estimate of the protected dual left turn saturation flow rates in the Tucson area. The data were collected from dual left turn lanes at six intersections. The headway times were measured in order to calculate the saturation flow rates at each of the study sites. Observations were made at four intersections with left turn protected and at two intersections with permitted plus protected left turns. Saturation flow was measured from the third to the last vehicle in the queue. Observations were made during the time of expected peak traffic flow. A stop watch was used to measure the time intervals to the nearest tenth of a second. The saturation flow rates were then calculated and varied from 1621 to 2017 Vehicles Per Hour of Green Per Lane (VPHGL) for the inside lane to 1737 to 1802 VPHGL in the outside lane.

Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2010. / Cataloged from PDF version of thesis. / Includes bibliographical references (p. 35). / Traffic simulation is an important aspect of understanding how people move throughout various road systems. It can provide insight into the design of city streets and how well they can handle certain traffic patterns. There are various simulators available, ranging from free tools such as TRANSIMS to commercial implementations such as TransCAD. The available tools provide complex, large scale and very detailed simulation capabilities. The Virtual City Testbed addresses aspects that are not available in these tools. Primarily, the test bed provides the ability for interaction with the traffic system in real time. Instead of basing the simulation solely on automated vehicle models, we allow for human participants to interact with individual cars via a remote simulation client. Thus we are able to inject realistic human input into our simulation. A second feature provided by our simulation is the ability to disrupt a simulation in progress. A disruption usually involves disabling access to a set of streets which forces the traffic to adapt as it moves around the road system. This yields a way to study the way traffic motion changes within a road system under the presence of unexpected events such as natural disasters or other real life disruptions. Ultimately, we provide a test bed for studying traffic under varying environmental conditions. / by Oleg I. Kozhushnyan. / M.Eng.

Highway systems world wide continue to see an ever increased number of vehicles and subsequently a rise in congested traffic. This results in longer commute times, wasted energy as vehicles idle in stop and go traffic, and increases the risk of accidents. In short, increased congestion costs time and money. These issues have prompted much research into Automated Highway Systems (AHS). In AHS vehicles using computer algorithms can safely travel at much smaller inter-vehicle distances than human drivers are capable of. This increases the capacity of existing highway systems. Sensors aboard each vehicle make this possible by monitoring their surroundings. Vehicles equipped with Adaptive Cruise Control (ACC) are capable of this type of close proximity travel. ACC packages are becoming common as a standard package on many mid-priced vehicles. Another form of automation, Cooperative Adaptive Cruise Control (CACC), which utilizes wireless communication between vehicles, has been proposed and will likely become available within the next couple decades. CACC allows each vehicle to communicate their intended speed or position changes to surrounding vehicles, further decreasing the possibility of collisions. These automation methods are proposed to reduce driver stress, increase highway throughput, and decrease accident rates. However, the fact that vehicles are being automated creates new opportunities for malicious individuals to wreak havoc on society. This research investigates the possibility that some vehicles on the highway might be under the control of malicious individuals who have modified their automated control systems to negatively affect vehicles around them. These malicious actors might also exploit the wireless communication of CACC vehicles and hack their control algorithms, causing them to become unstable. These hacked vehicles could become passive participants in the attack unbeknownst to the driver of the vehicle. The result of such attacks could be congested traffic, rapid changes in acceleration causing drivers discomfort, or multi-vehicle collisions. Such attacks could effectively negate the benefits of implementing AHS. The goal of this work is to bring to light possible weaknesses in the proposed systems so they can be rectified before becoming an issue to the public at large.

At head of cover title: Australian Road Research Board / Bibliography: leaves 108-114 / xi, 114 leaves : ill ; 25 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, 1971

Thesis (M.A. in City and Regional Planning)--University of California, Berkeley, Fall 2005. / Title from PDF title page (viewed Dec. 13, 2007). "Fall 2005." Includes bibliographical references (p. 81-87).

In recent years, traffic congestion in transportation networks has grown rapidly and has become an acute problem. The impetus for studying this problem has been further strengthened due to the fast growing field of Intelligent Vehicle Highway Systems (IVHS). Therefore, it is critical to investigate and understand its nature and address questions of the type: how are traffic patterns formed? and how can traffic congestion be alleviated? Understanding drivers' travel times is key behind this problem. In this paper, we present macroscopic models for determining analytical forms for travel times. We take a fluid dynamics approach by noticing that traffic macroscopically behaves like a fluid. Our contributions in this work are the following: (i) We propose two second-order non-separable macroscopic models for analytically estimating travel time functions: the Polynomial Travel Time (PTT) Model and the Exponential Travel Time (ETT) Model. These models generalize the models proposed by Kachani and Perakis as they incorporate second-order effects such as reaction of drivers to upstream and downstream congestion as well as second-order link interaction effects. (ii) Based on piecewise linear and piecewise quadratic approximations of the departure flow rates, we propose different classes of travel time functions for the first-order separable PTT and ETT models, and present the relationship between these functions. (iii) We show how the analysis of the first-order separable PTT Model extends to the second-order model with non-separable velocity functions for acyclic networks. (iv) Finally, we analyze the second-order separable ETT model where the queue propagation term - corresponding to the reaction of drivers to upstream congestion or decongestion - is not neglected. We are able to reduce the analysis to a Burgers equation and then to the more tractable heat equation. / Singapore-MIT Alliance (SMA)

The calculation of path travel times is an essential component for the dynamic traffic assignment and equilibrium problems. This paper presents a simulation method for calculating actual path travel times for the traffic network with dynamic demands. The method is based on a path-based macroscopic simulation model of network traffic dynamics. There is no need to explicitly model intersection delays in this method. Discontinuity in the travel time caused by traffic light control can be captured by this method. It's flexible in terms that the model is not limited to a specific velocity-density relationship. Some numerical results for signalized and unsignalized networks are reported. / Singapore-MIT Alliance (SMA)

by Andrew Kurkjian ... [et al.]. / Bibliography: p. 63-64. / "April 1979." / U.S. Department of Transportation contract DOT-OS-60137

Thesis (Master)--Concordia University (Canada), 2000. / Advisers: Maria Elektorowicz, John Zacharias. Includes bibliographical references.

The Kinematic-wave model is one of the models proposed to simulate vehicular traffic. It has not received widespread use because of poor understanding of associated interface conditions and early use of incorrect numerical schemes used. This thesis analyzes mathematically correct boundary and interface conditions in the context of the Godunov method as the numerical scheme for the simulation software created. This thesis simulates a set of scenarios originally proposed by Ross, to verify the validity of simulation. The results of the simulation are compared against the corresponding results of Ross, and against intuitive expectation of the behavior of actual traffic under the scenarios. Our results tend either to agree with or improve upon those reported by Ross, who used alternate models.