Hesham Rakha

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Recent progress in technology has facilitated the design, testing, and deployment of traffic signal priority strategies for transit buses. However, a clear consensus has not emerged regarding the evaluation of these strategies. Each agency implementing these strategies can have differing goals, and there are often conflicting issues, needs, and concerns(More)
This paper involves a field test on 60 test participants to characterize driver behavior (perception-reaction time (PRT) and stopping/running decisions) at the onset of a yellow phase. Driver behavior is analyzed for five trigger distances that are measured from the vehicle position at the start of the yellow indication to the stop bar. This paper(More)
The paper characterizes driver behavior at the onset of a yellow-phase transition on high-speed signalized intersection approaches using field data gathered from 60 test subjects (approximately balanced in gender and age). The driver stopping/running decisions are analyzed for five trigger distances as drivers approach the intersection at a speed of 72 km/h(More)
Within the context of transportation modeling, driver route choice is typically captured using mathematical programming approaches, which assume that drivers, in attempting to minimize some objective function, have full knowledge of the transportation network state. Typically, drivers are assumed to either minimize their travel time (user equilibrium) or(More)
The estimation of path or trip travel-time reliability is critical to any advanced traveler information system. The state-of-practice procedures for estimating path travel-time reliability assumes that travel times follow a normal distribution and requires a measure of trip travel-time variance. The study analyzes AVI data from San Antonio and demonstrates(More)
Traffic simulation models have the potential to provide a cost-effective, objective, and flexible approach to assessing design and management alternatives, particularly when these alternatives involve the emerging technologies of Intelligent Transportation Systems (ITS). However, in order for this potential to be realized, models must be valid for the(More)
This paper provides an attempt at evaluating the safety impacts of an Adaptive Cruise Control (ACC) system relative to Conventional Cruise Control (CCC) utilizing data that were gathered as part of a Field Operational Test (FOT) in Ann Arbor, Michigan. The safety of the ACC system is quantified considering three surrogate safety measures. The first safety(More)
The authors examine the traffic engineering potential and limitations of routeing strategies that are system optimized, as opposed to routeings that minimize the travel times of individual drivers. This examination is based on a simple two-route traffic network. The user- and system-optimum traffic assignments are illustrated for this network, and the(More)