Wednesday, November 2, 2022
Virtual on Zoom
Proper calibration process is key for traffic safety evaluations using simulation models. Allowing for a with and without comparison under controlled environment that is not directly testable in the field, microsimulation-based approach has drawn considerable attention for the performance evaluation of emerging technologies, including connected vehicle (CV) safety applications. Different from the traditional approaches to evaluate mobility impacts, safety evaluations of such applications demand the simulation models to be well calibrated to match real-world safety conditions. This seminar will present a novel calibration framework which combines traffic conflict techniques and multi-objective stochastic optimization to calibrate the operational and safety measures simultaneously. The conflict distribution of different severity levels categorized by time-to-collision (TTC) is applied as the safety performance measure. Simultaneous perturbation stochastic approximation (SPSA) algorithm, which can efficiently approximate the gradient of the multi-objective stochastic loss function, is used for model parameters optimization that minimizes the total simulation error of both operational and safety performance measures. A case study will be demonstrated by calibrating a microscopic simulation model to evaluate CV safety applications as a part of the NYC Connected Vehicle Pilot Deployment Program.
Dr. Kaan Ozbay is a Professor at New York University's Tandon School of Engineering, and Director of C2SMART Center, a Tier 1 USDOT University Transportation Center. Dr. Ozbay served as Principal Investigator (PI) of the NYU/C2SMART team as part of the NYCDOT-led New York City Connected Vehicle Pilot, under USDOT's Connected Vehicle Pilot Program. He joined NYU's Department of Civil and Urban Engineering and Center for Urban Science and Progress (CUSP) in August 2013, and is also Global Network Professor of Civil and Urban Engineering, NYU Abu Dhabi (NYUAD) and Global Network Professor of Engineering and Computer Science, NYU Shanghai (NYUSH).