Optimal and Adaptive Signal Control of Diamond Interchanges
Professor Clara Fang of the department of civil, environmental, and biomedical engineering at the University of Hartford will deliver the second lecture in the Fall 2005 Operations Research / Management Science Seminar series.
Title: Optimal and Adaptive Signal Control of Diamond Interchanges
Abstract: This research has developed a methodology and a corresponding implementation algorithm to provide optimal signal control of diamond interchanges in response to real-time traffic fluctuations. The problem, solved by a forward dynamic programming (DP) method, is formulated as to find a phase sequencing decision with a phase duration that makes a pre-specified performance measure minimized over a finite horizon that rolls forward. The optimal signal switches over each 2.5-second interval are found for each horizon of 10 seconds. The optimization process is based on the advanced vehicle information obtained from loop detectors set back a certain distance from the stop-line. Vehicle trajectories from detections till future arrivals and departures are modeled at the microscopic level to estimate the traffic flows at the stop-line for each horizon. The DP algorithm is coded in C++ language and dynamically linked to AIMSUN, a stochastic micro-simulation package, for evaluation. The simulation results have exhibited that the DP algorithm is superior to PASSER III and TRANSYT-7F in handling demand fluctuations for medium to high flow scenarios when the field demand is increased from the one used in off-line optimization. The performance of the three algorithms is almost identical if the simulation demand is similar to off-line demand situation and dose not vary much.
This series is organized by the UMass Amherst INFORMS Student Chapter. Support for this series is provided by the Isenberg School of Management, the Department of Finance and Operations Management, and the John F. Smith Memorial Fund.
Check here for more details about this speaker series.
