Optimization Model for Traffic Signal Control with Environmental Objectives

A bi-level optimization model with environmental objectives is proposed to describe the traffic signal control under the user-equilibrium constrains. The performance index function for optimization is defined to improve traffic quality and reduce emission at intersections. The heuristic genetic algorithm and its solution with the aid of Genetic Algorithm (GA) tool of Matlab are presented so that the optimal signal cycle length and green time are obtained. At last, a case study illustrates the applications of the model and its algorithm. It is concluded that the bi-level optimization model for traffic signal control of intersections with environmental objectives is feasible.