Timing in traffic lights is influnced by value of traffic volume, Saturation capacity in each approach and Type of movement. Increasing the number of phases is caused increase in ratio of beginning and ending loss, and total loss to cycle of time which it is decreasing the intersection efficency. In other hand, decreasing in number of phases is caused left turning movement of vehicles is permited. In permited turning, left turn equivalent factor true car has a great effect on Congestion of traffic. With considering different parameters can effect on left turning movement traffic factor, six approach in five signalized intersection is Examined in isfahan intersections. and This coefficient influnced from condition of this intersection from aspect of traffic and geometric of intersection using advices of HCM is compared. Information of each intersection after of gathering using linear Regression and S-pluss software is applied in order to make a model for left turning movement. After make a statistical model, using neural network in MATLAB software, data correlation and therefore a model is proposed for evaluating of parameters. Finally with applying of one traffic simulator software (HCS), traffic flow in these intersection simulated. Simulatin in first step accomplish with using HCM standards, and their quantities calculated.whenas in next step from calculated quantities, is used in left turning movement, then output are compared. From case study in this thesis is explained that quantities of E L In HCM between 10 percent to 37 percent depend on volume of different approach more than quantities calculated in these intersetion. Lower values of E L coefficient towards refrences and following that higher capacity of these intersection are the important results of this thesis. Key words: Permitted left turn, signalized intersection, timing, intersection deley.
