Most previous works of transit signal priority merely focus on optimization of signal timings. Bus speed and dwell time at bus stop are used as exogenous inputs. This paper presents a novel approach for integrated optimization of bus holding time at bus stop, signal timings, and bus speed to provide priority to buses at isolated intersections. The objective of the proposed model is to minimize the total intersection cost that includes bus delay and the impact on the overall trafcc near the intersection in the meantime, to the maximum extent possible, ensure bus clearing the intersection without stop by the red light. A set of formulations are developed to capture explicitly the interaction between bus speed, bus holding time and transit priority signal timings. Experimental analyses have shown that the proposed integrated operational model outperforms the no priority, signal priority only, and signal priority with holding control strategies (no bus speed adjustment) in terms of reducing average bus delays and stops, and only causes little acceptable negative impacts on general traffic. The sensitivity analysis has further demonstrated the potential of the proposed approach to be applied in real-time bus priority control system under different levels of traffic demand.
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