Study On Public-travel Traffic Information Service System And It's Key Problems

Traffic information service system is an important part of Intelligent Transportation System. It is necessary for modern traffic development and administration. Public-travel traffic information service system contains three parts: traffic information collection, traffic information treatment and traffic information issuance. Many kinds of traffic information issuance methods are adopted to provide traffic information for the public. It is arranged as "overall to partition" in the thesis and some problems of public- travel traffic information service system are studied in the thesis.Detailed demand analysis of public- travel traffic information service system including public- travel traffic information, travel object and functional demand is given at the beginning of this thesis. The necessity of constructing public- travel traffic information service system is brought forward. Data flow of public-travel traffic information service system is analyzed and logical structure of the system is given.Public-travel traffic information service system which is divided into three parts including traffic information collection, traffic information treatment and traffic information issuance is studied in this thesis. Based on the advantages and disadvantages of different collecting methods, flow of traffic information collection is given. Besides, problems of GPS equipped floating car traffic information collection are discussed. Based on requirements of different traffic parameters measurements, methods of determining probe vehicle sample sizes are analyzed. From the point of view of the probability theory and considering precision of orientation and efficiency of correspondence, the thesis raises an improved method of determining floating car sample sizes.Traffic information obtained from collecting system has to betreated so that it could become useful information to release. This thesis analyzes pretreatment methods of three kinds of dynamic traffic information and the flow of dynamic traffic information pretreatment. The prediction method of road traffic parameters is studied based on information fusion technology. Besides, structure of traffic information treatment subsystem is given in this part.There are various modes of traffic information issuance, but not all of these can be used anytime and anyplace. This thesis analyzes the characteristics of different kinds of traffic information issuance. Functional configuration of traffic information issuance subsystem is also analyzed. Via analyzing and comparing different kinds of information technologies, network topological structure of traffic information issuance subsystem is given in this thesis.