Research On Key Theories And Methods For Cooperation Of Urban Traffic Control System And Urban Traffic Flow Guidance System

Urban Traffic Control and Urban Traffic Flow Guidance are two main measures of traffic management. The cooperation of Urban Traffic Control System (UTCS) and Urban Traffic Flow Guidance System (UTFGS) is the development direction of the modern traffic management. Because of the traffic problems such as traffic jam are increasingly serious, the cooperation of UTCS and UTFGS is the problem to be solved mostly in the modern urban traffic management. The traffic flow of road network can be dynamicly assigned from time and space through the cooperation of UTCS and UTFGS. The cooperation of UTCS and UTFGS can improve traffic management efficiency and the whole system functions, which is better than each subsystem function independently.The research in this paper is outspreaded mostly around the integration requirement of UTCS and UTFGS—Intelligence and Integration. This paper involves seven chapters:Chapter One: Introduction.The meaning of cooperation of UTCS and UTFGS is presented from the angle of Synergetics, the necessity of cooperation about UTCS and UTFGS is analysed from the relevancy and differentiation. The characteristics of the cooperation system are also analysed. This paper reviews and summarizes the cooperation patterns, cooperation models and algorithms of UTCS and UTFGS roundly. At last, the purpose and meaning of this research, the main research content and the composing of the whole paper are presented. Chapter two: Research on cooperation framework of UTCS and UTFGS based on MAS.The principle and technique of agent is introduced. The Distributed Hierarchal Architecture of UTCS and UTFGS based on Multi-agent System (MAS) is presented after analysing the characteristics of traffic flow. The basic idea is: when the cooperation opportunity hasn't come, we use self-governed mode; when the cooperation opportunity is coming, we use integrative mode. The configuration of agent model is established, and blackboard-based coordination mechanism between agents is presented.Chapter three: Determination of cooperation opportunity and dynamic partition of cooperation subareaThe determination of cooperation opportunity provides theoretical foundation for the implementation of cooperation strategy from the angle of time,namely when to carry out cooperation. After analyzing the phenomena of traffic jam and the variety of traffic parameters, the twice deternimation arithmetic of cooperation opportunity is presented. Using this arithmetic, one example is calculated. The result shows that the arithmetic can supervise the traffic flow state and hint the phenomena of jam or dissipation quickly. This method can find out the cooperation opportunity effectively.The dynamic partition of cooperation subarea provides theoretical foundation for the implementation of cooperation strategy from the angle of space,namely where to carry out cooperation. After analysing the principles of dynamic partition about subarea, the dynamic partition of cooperation subarea based on key intersection principle and traffic volume principle is presented. The material partition process is provided. Different projects are carried out in different subareas. The whole optimization of road network can be realized by local optimization.Chapter four: Research on optimum cooperation model of UTCS and UTFGS The integration model of UTCS and UTFGS is established from the angle of system optimization, whose goal is minimizing the total travel time. Make the control and Guidance projects as the components. Different with prevenient cooperation models, this model considers the harmony of intersections in cooperation subarea. It introduces the variable of offset into model, it divides delay at the intersection into two instances: the head of motorcade is blocked and the middle of motorcade is blocked. This method can make the travel time calculated much more exact. This paper uses genetic algorithm to solve the model after analysing the differentces between genetic algorithm and traditional methods. The material process of solving the model and the design of coding mode, fitness funtion and genetic operators are provided. The variables'value of control and guidance can be received at the same time through solving the model. The traffic flow of road network will be assigned at the same time from time and space. And then the genuine cooperation of UTCS and UTFGS will be realized. We make GA program using program using Visual C++ and upbuild a small road network to simulate and test by VISSIM, the results show that the model and algorithm can reduce the total travel time effectively and improve moving efficiency of the road network.Chapter five: Foundation of evaluation index system about the cooperation of UTCS and UTFGS.Cooperative evaluation is the essential tache before implement of cooperative items. This paper sets up the evaluation index system about the cooperation of UTCS and UTFGS using aim-hierarchy expanding taxonomy and maximum unrelated principle based on the selection principle of the cooperation evaluation indexes. This paper mainly evaluates the cooperation effect. It contains some aspects such as improving degree of convenience and comfort about traffic sysytem, improving security of traffic system, improving moving efficiency of traffic system, reducing environment pollution, reducing waste of energy sources and so on. The signification of every evaluation index is provided.Chapter six: Research on evaluation method of cooperation about UTCS and UTFGS.After contrasting some comprehensive evaluations, this paper evaluates the cooperation effect using the method of Fuzzy Comprehensive Evaluation based on Analytic Hierarchy Process (AHP-FCE). The evaluation principle and process are provided. We can not only determine the degree of cooperative effect, but also compare different projects. At last, we evaluate before and after the implementation of cooperation method, the later comprehensive index has been increased much higher than the former. It shows the validity of this evaluation index system and evaluation method. Also it shows the feasibility of the cooperation method provided in this paper from cooperation effect.Chapter seven: Summarization and Expectation.The main research achievements and further study problems are pointed out.