The Research Of Signal Optimization Based On Maximization Researve Capacity Of Road Network

Traffic assignment and signal optimization is a research of the urban traffic network design problem (NDP), The traffic distribution and signal optimization problems are extremely challenging because of the traffic network has the characteristics of large and complex, Any time of traffic network modification and optimization needs after careful planning and calculation and analysis.So for traffic network optimization problem of research not only has to guide practical traffic management significance, but also has the important theoretical value for study.In order to achieve the aim of increasing traffic network tolerance and improve traffic network usage efficiency, This paper combined with the traffic flow characteristics and the signal control parameters to optimize, but escape for rebuilding and diffusing the road.Under the guidance of the concept above,This paper firstly describe the research significance of traffic assignment and signal optimization combination,Combining the current domestic and international situation,this paper give the main research contents and the theme structure.Because of research needs,In this paper, the traffic network and its spare capacity, traffic distribution principle (key for equilibrium traffic assignment) traffic signal control basic theory is also briefly introduced,And the commonly used traffic impedance functions of generalization,The linear programming, nonlinear programming and bi-level programming model and algorithm are briefly described.Based on the analysis of different flow of entering the intersection, this paper thinks that the time delay and steering traffic signal control parameters have relationships and establish separate intersection delay function and steering intersection delay function is coupled to the user steering optimum equilibrium network distribution of Beckmann transform type, the lower programming model is established;For the aim of maximizing the network reserve ability, The upper programming model is established considering the signal control constraint; based on the bi-level programming model features,the solving algorithm is designed using the sensitivity analysis method through a simple example to prove this idea,Finally this paper give a summary and problems to study in the further.