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The development and role of accident predictive modelsChatterjee, Kiron January 1995 (has links)
No description available.
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Effects of Connected Vehicle Technology on Mobility and Mode ChoiceMinelli, Simon 11 1900 (has links)
Connected vehicle is a fully connected transportation system in which vehicles, infrastructure, and mobile devices are enabled to exchange information in real-time to bring advancements in transportation operations. It is important to incorporate the new characteristics of the connected vehicle in the transportation planning process. Also, it is vital for planning and road agencies to better understand the impacts of connected vehicle on transportation networks, system demand, and travel behavior of road users in order to properly prepare for them. In addition, developers of connected vehicle systems can gain insight into how their systems will impact road users and network performance. When a change in performance of a transportation network occurs it can potentially cause users to change travel modes, known as mode choice. In this research, the change in mode choice, due to the change in network performance by introduction of connected vehicle is studied. This provides a more accurate depiction of the performance of the network and indicates how connected vehicles could change travellers’ preference in travel mode. The effect of this technology is explored on the performance of the Toronto waterfront, in a microsimulation environment. The results show that average travel time increases for high market penetrations when a dynamic route guidance algorithm is implemented, a phenomenon that occurs in dense, and complex traffic networks. Analysis of mode choice shows a loss in the auto mode share, for high market penetrations, due to the increased auto travel times. This loss in the auto mode share is compensated by increases in the other modes. / Thesis / Master of Applied Science (MASc)
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A Microsimulation Approach Assessing the Impact of Connected Vehicle on Work Zone Traffic SafetyGenders, Wade 06 1900 (has links)
Safety in transportation systems is of paramount concern to society; many improvements have been made in recent decades and yet thousands of fatalities still occur annually. Work zones in particular are areas with increased safety risks in transit networks. Advances in electronics have now allowed engineers to merge powerful computing and communication technologies with modern automotive and vehicular technology, known as connected vehicle. Connected vehicle will allow vehicles to exchange data wirelessly with each other and infrastructure to improve safety, mobility and sustainability. This thesis presents a paper that focuses on evaluating the impact of connected vehicle on work zone traffic safety. A dynamic route guidance system based on decaying average-travel-time and shortest path routing was developed and tested in a microscopic traffic simulation environment to avoid routes with work zones. To account for the unpredictable behaviour and psychology of driver’s response to information, three behaviour models, in the form of multinomial distributions, are proposed and studied in this research. The surrogate safety measure improved Time to Collision was used to gauge network safety at various market penetrations of connected vehicles. Results show that higher market penetrations of connected vehicles decrease network safety due to increased average travel distance, while the safest conditions, 5%-10% reduction in critical Time to Collision events, were observed at market penetrations of 20%-40% connected vehicle, with network safety strongly influenced by behaviour model. / Thesis / Master of Applied Science (MASc)
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An adaptive strategy for providing dynamic route guidance under non-recurrent traffic congestionLee, Sang-Keon 06 June 2008 (has links)
Traffic congestion on urban road networks has been recognized as one of the most serious problems with which modern cities are confronted. It is generally anticipated that Dynamic Route Guidance Systems (DRGS) will play an important role in reducing urban traffic congestion and improving traffic flows and safety. One of the most critical issues in designing these systems is in the development of optimal routing strategies that would maximize the benefits to overall system as well as individual users.
Infrastructure based DRGS have advantage of pursuing system optimal routing strategy, which is more essential under abnormal traffic conditions such as non-recurrent congestion and natural disaster. However user compliance could be a problem under such a strategy, particularly when some of equipped drivers are urged not to choose minimum travel time path for the sake of improving the total network travel time. On the other hand, In-vehicle based DRGS can utilize the user-specified route selection criteria to avoid "Braess Paradox" under normal traffic conditions. However, it may be of little use under abnormal traffic conditions and high DRGS market penetration.
In conducting the comparative analysis between system optimal strategy and user equilibrium strategy, significant differences were found within the mid-range traffic demand. The maximum total travel time difference occurs when the level of traffic demand is half of the system capacity. At this point, system optimal route guidance strategy can save more than 11% of the total travel time of user equilibrium route guidance strategy.
The research proposes an adaptive routing strategy as an efficient dynamic route guidance under non-recurrent traffic congestion. Computation results show that there is no need to implement system optimal routing strategy at the initial stage of the incident. However, it is critical to use system optimal routing strategy as freeway and arterial are getting congested and the queue delay in freeway increases.
The adaptive routing strategy is evaluated using Traffic simulation model, INTEGRATION. According to simulation results using an ideal network, the travel time saving ratio is maximum when both arterial and freeway have normal traffic demand under incident. In case of a realistic network, the adaptive routing strategy also proved to save the total travel time between 3% to 10% over the traditional user equilibrium routing strategy. The reduction of total travel time increases as the incident duration increases. Consequently, it is concluded that the adaptive routing strategy for DRGS is more efficient than using user equilibrium routing strategy alone. / Ph. D.
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