Control And Manage For Urban Main-Road

For both developing and developed countries ,effective transportation systems are of primary importance in the development of society and economy. The establishment of efficient traffic models to reveal fundamental traffic characteristics is an essential requirement in the design ,planning and operation of transportation systems .Cellular automata (CA) are non-liner dynamical system in which space,time and state values are discrete ,Using simply rules ,CA has attained very good results in simulating several complex natural phenomena and physical problem .That enlightens people to simulate traffic flow by CA method .Urban major road performs critically on dredging traffic ,Therefore ,It is very necessary to study the control and manage for urban main-road .In this thesis ,firstly we introduce the recent studies on traffic flow ,which based on the statistical physics ,secondly the fundamental principles and characteristics of one-dimension (1D) determined CA model (DCA) and two-dimension determined CA model (BML) are described in detail. Based on these models ,a main-road traffic flow model with two speeds on one dimension is designed . This model simulate the situation of one road in the city ,traffic lights placed on the crossing ,using the computer simulation ,Firstly ,in the case of synchronized traffic lights ,we investigated the velocity and flow of the model when the initial density ,the turning probabilities ,the number of the traffic lights ,the green to signal ratio and the period of the signal are changed ,then we have advanced some meliorate measure to traffic flow ;Secondly ,in the case of the traffic lights' signal update delay in turn ,we found the optimal matching between the period of the signal and the delay time of the traffic lights so as to the perfect velocity and the flow of the model are attained.