Coordination of semi-actuated signals on arterials

This paper formulates an integrated mixed-integer nonlinear programming model for coordinating semi-actuated signals on arterials, with the vehicle actuation logic explicitly modeled and embedded. The decision variables are the common cycle length; offset points; phase sequences; green splits of the major phases; minimum green, unit green extension and maximum green of the minor phases which are optimized simultaneously. Two algorithms are employed to search for the optimal signal plans: one is the traditional genetic algorithm (GA), and the other is a GA-based heuristic to save computation effort in earlier search stages. Numerical example is carried out to demonstrate the proposed model and algorithms.