The Studies Of Cellular Automata Models Of Traffic Flow With Open Boundary Conditions

Cellular automata (CA) is nonlinear dynamical system in which space, time and state values are discrete. By using simply rules, CA has attained very good results in simulating variable complex natural phenomena and physical problems. That enlightens people to simulate traffic flow by CA models.First, the recent studies of CA models for traffic flow, based on the statistical physics, are introduced in the thesis. At the same time, all kinds of models based on the determined CA are also introduced in detail. Second, we introduce the improved NS model presented by XueYu to the CA traffic flow model of a two-lane roadway in a highway and on a urban main road.In the third chapter, an improved CA model of the traffic flow in the two-lane roadway is proposed to describe highway traffic under the open boundary conditions by the consideration of the relative motion of vehicles and the relation of deceleration probability. Numerical simulations have been carried out. The results show the complicated evolution process of traffic flow. The flow of vehicles can be controlled by the coupling coefficient. Different values of have different effects on the critical point from free to jam phase.In the fourth chapter, we consider the effect of bus stations on traffic flow. By Numerical simulations, we attain the idea results.In the fifth chapter, a multi-speed CA traffic flow model on the one-dimen-sional urban main road on the control of traffic lights is proposed to simulate the traffic under the open boundary conditions.