Research On Urban Area Traffic Signal Control Based On Short - Term Traffic Flow Forecast

Urban transport problems is an important factor troubled urban development, restricting urban economic construction. Traffic guidance and traffic control are main solutions to solve the problem of traffic congestion and short-term traffic flow forecasting is the key technology to achieve traffic guidance and control. In this paper, we study the short-term traffic flow forecasting as the breakthrough point, and improve and optimize the shortcomings of this algorithm, and we propose the urban traffic signal control scheme based on improved short-term traffic flow forecasting model.Firstly, the thesis introduces the research background and practical significance, summarizes main models of short-term traffic flow forecasting, and introduces some representative urban traffic signal control systems at home and abroad. And briefly introduced neural network and wavelet theory and the combination of both that is wavelet neural network, we use wavelet neural network as framework to build a short-term traffic flow forecasting model. In view of the problem that the number of hidden layer nodes of wavelet neural network is difficult to determine, a bilateral search method based on empirical formula is proposed to find the optimal value; for the problem of slow convergence and easy to fall into local minimum, we added momentum term and adaptive learning rate in the network training process and optimize the initial parameters with genetic algorithm. The improved forecasting model is simulated and compared with other traditional forecasting models by using the actual traffic flow data, the simulation results show that the forecasting model has good results.Secondly, the thesis introduces the theory of urban regional traffic signal control. The urban area is divided into some sub-regions, then we forecast the traffic flow data of the sub-region by using the improved forecasting algorithm, based on these data, the key intersection and main road of the sub-region are determined. The control of the sub-region is realized through the control of main road and others, and the control of the urban area is realized through the coordinated control of sub-regions. Then we compare the proposed control scheme with traditional timing control scheme, the simulation results show that the proposed scheme has better control effect and certain application value.Finally, the thesis summarizes the results of research, and put forward the shortcomings of this paper and some directions for further research.