Urban Traffic Flow Modeling And Dredging Application

Nowadays,the rapid increase in private cars,the low efficiency of traffic control system has been the major reasons that caused the urban traffic congestion.The current traffic control system traffic has been unable to meet the requirement of avoiding urban congestion,hindering the application of intelligent traffic system.The static way used in vehicle traffic at intersections and traffic networks is one factor induced such low traffic efficiency.Effective balance and dynamic method done in traffic control at each intersection and traffic network,as well as intelligent traffic management system with various algorithms,will greatly improve the traffic efficiency,and alleviate or solve the existing urban traffic congestion.The guaranteed low delay network required for the development of intelligent traffic with the large-scale construction of communication infrastructures,as a result,will be help for improving urban traffic efficiency.Based on the above background and problems as well as the National Electronic Manufacturers Association Dual-Ring(NEMA)phase control logic,this study is focused on analyzing the topological structure of the intersections and traffic networks,building a store-and-forward traffic model,and proposing a way to disperse vehicles on the roads and reduce congestions.The main works and results of this thesis are shown as below.1.As for the two-phase and four phase urban road intersections with fixed period,a study on the signal timing method used in urban intersections based on cooperative game had been proposed.In detail,the vehicles in the first,and second and the ones in all fourth phases are taken as the participants of the cooperative game.The green time allocated for each phase is settled as the strategy set of the game.The number of vehicles queuing in each corresponding road is labeled as the winning value of the game.The Shapley valuation method is carried out to solve the game process,and to obtain the variation of the queuing length in each phase with the game cycle.Finally,verifying by MATLAB simulation experiments,the passage efficiency of the proposed scheme was improved by 20%.2.For the traffic maximization required by the urban traffic network and communication network,the investigation had been done on the traffic maximization algorithm of urban road network based on Ford Fulkerson algorithm.With carefully analyzing the urban road network structure,as a result,an urban traffic network model is established.The parameters including upper limit traffic capacity and real-time traffic flow of each road section were recognized.The augmentation path will be found and selected with the Ford Fulkerson network.MATLAB simulation results show that the goal of space-time equilibrium can be achieved with our proposed scheme.In summary,the vehicle grooming algorithms were proposed for the intersection and urban road network.The vehicle congestion at intersections and road networks can be effectively alleviated with the signal timing method used in urban intersections based on cooperative game and the traffic maximization algorithm of urban road network based on Ford Fulkerson algorithm.They also improve the utilization ratio of both the urban intersection and the road network,and achieve the balanced allocation of space-time resources,demonstrating application value.