The Modeling And Characteirstics Researching On Two-dimensional Traffic Flow In Real Traffic Of The Roads

Our country is a developing country, the traffic problem in the city has becamevery serious so that restrict the development of city on the diversified andconvenient. The traffic problem has become a hot spot of the current problems,engaged in the research of the theoretical model in a variety of version, on whichmainly by the basis of the research on the cellular automata model, and guide thenew chapter of intelligent transportation system. This topic is based on the basicprinciple of the cellular automata, researching on the characteristics of2-d trafficmodel of traffic flow,it includes the urban traffic density, velocity, traffic flow,acceleration, lane changing probability, driving rules, green wave rate andintersection setting,in which has an important influence on the transport networkSettings and the layout structure.This article mainly from the following three aspects:(1) a H crossroads inurban areas narrow lanes place very easy to see, in the open boundary conditions, theredirecting probability in the intersection of vehicle will generate interference in thetraffic flow, so as to establish the H cellular automata model. Through the researchto probability and traffic light setting on traffic flow characteristics influence, andpoints out that between the position point of quantitative change and the changing ofredirecting probability, in addition to the average speed is closely related to it, andtraffic lights timing differences so as to reduce vehicle interference and increasetraffic flow, at the same time, play analysis to the critical redirecting probability onthe traffic flow significance.(2) Based on the driving-lane problem in the crossintersection of two-dimensional traffic network with traffic lights, put forward afour-direction traffic model，and it included the parameters of acceleration and theprobability of change lanes is putting the impact on traffic flow, took advantage ofthe methods of cellular automata of2-d traffic flow model so as to simulate thewhole dynamic process of vehicle. Lane changing probability reveal the problemfrom a side to the vehicles in urban transportation driving, and lane changing is anindispensable factor in traffic, besides increasing maximum flow is the main purpose.(3) In1992,based on Biham, Middleton and Levine proposed2-d (BML) model andthe symmetrical2-d cross road conditions were studied. Considering the mechanismof redirecting probability and the green wave parameters on the influence of traffic flow, and through the computer simulation that the whole dynamic process of trafficrunning. The redirecting probability and boundary conditions on the traffic lanespresent different characteristics in phase change, and the simulation shows that thevehicle from free movement phase to maximum flow phase or blocked phase, the twoexternal factors produce organization function on implementing lanes traffic.(4)Different vehicles under the mixture ratio of traffic flow, two-lane bidirectionalstrong coupling or weak coupling, present basic characteristics consistent, butcritical value different, in the emergence of local mixed vehicles for traffic flowplays a leading role, and affect the entire traffic.