Coordinated Optimization Of Bus Priority Signal And Departure Frequency

High efficiency,low energy consumption,and environmental characteristics of public transport have been considered as effective measures in improving urban air quality and traffic congestion,which are important contents of public transport development to improve the efficiency and service level of public transportation.It is also one of the focuses of scholars in China and abroad.The departure frequency and the bus signal priority are two important contents of public transportation dispatch,and the two are interrelated with each other.However,in current studies,the departure frequency optimization considers only the traffic of the lines and vehicle ownership,while the impact of the bus signal priority on the departure frequency are rarely considered;and vice versa.Therefore,this thesis considered the relationship between the bus priority signal and the departure frequency,constructed a two-layer planning model which is coordinated and optimized to further improve the dispatch level of public transportation.Firstly,this thesis analyzed the current situation f domestic and international research on the frequency of public transportation and the priority of public transit signal.In this thesis,the influencing factors and methods of frequency are expounded and the control methods such as passive priority,active priority and real-time priority are analyzed.Secondly,considering that bus signal priority of single intersection and departure frequency are correlated,the bi-level programming model is proposed to optimize the two.The upper layer is a frequency optimization model with the smallest of the passenger and bus travel total cost,the lower is an active bus signal priority model.An iterative optimization algorithm for bi-level programming model is designed.The upper layer programming model is solved by genetic algorithm and the experimental analysis is carried out to verify the validity of the model.Then,considering the interaction between the adjacent bus intersections,a linkage control method of the adjacent bus intersections of the same bus line is constructed.And a bi_level programming model is constructed that coordinates the traffic priority linkage control of bus and the frequency of the line.The iterative optimization algorithm of bi-level programming model is designed and anayzed experimentally.The experimental results shows that this coordination optimization can effectively reduce the total cost of buses and passengers.The thesis takes full account of the interaction between signal priority and departure frequency.The frequency is optimized by taking into account the interests of passengers and operators.It provides a new method and train of thought for improving the level of public transportation dispatching and operating efficiency.