Study On Dynamic Traffic Information Collecting Processing And Sharing Technology Of Public Travel In Central City

With the development of intelligent traffic systems, more and more attentions have been paid to ATIS(Advanced Transportation Information Service). The hotspot of the research is turning from theory and technology to practical application. Constructions of various ATIS systems have been also in proceeding. ATIS which is based on information network is the core of ITS and can supply timely information of road traffic, public traffic, traffic transferring, traffic weather, parking and other information related to traveling. People who will go out can decide their way and route according to those information. Public traveling information service which is an important part of ATIS is made up of three parts: information collection, data processing and information publishing. And information collection is the precondition to realize of public traveling information service.To implement advanced traffic information service for public traveling, the precondition is the identify of real-time and accurate road traffic running state. So the acquiring of real time, sufficient, accurate dynamic traffic information flow is very important. Nowadays, single, static traffic information can't satisfy travelers. What they need are 'point-to-point' traffic decision-making information before traveling, 'play to score' dynamic traffic information during traveling and 'effective' traffic feedback information. But the devices for current dynamic traffic information are all single ones, which haven't been conformed and have low overlay rate. The technology of collecting traffic information with floating car, which is a research with emphasis, is an effective supplement and perfection.In order to implement advanced traffic information service for travelers, besides the acquiring of dynamic traffic information, the integration of related information of traveling services is a necessity. However, subsystems for traffic information were developed in different time which have different operation functions. They were developed with different developing tools, different operating system platforms and different database platforms. Because of those above, the operation can hardly implement effective transferring among different subsystems. So the resulted 'information isolated island' problem lock useful information in a serials of subsystems. On this background, service oriented architecture (SOA) emerged as time requires, which divides the functions of subsystems in different granularities. So, to implement information sharing, the transferring of functions among different subsystems converted to the transferring of different services.This paper discusses technology of information sharing and collecting in the aspects of the collecting of dynamic traffic information, information sharing, data processing, information publishing and system implementation.Firstly, based on detailed explanation of basic principles, advantages, disadvantages and structures of technology about information collection using floating cars, algorithms of map-matching based on data collection through floating car and timing on section of journey are brought forward for the first time. The feasibility and superiority of the two algorithms are also validated through concrete examples. Those two algorithms can preferably solve problems of dynamic traffic information collection and disposition based on floating car technology.Secondly, methods of how to confirm minimum quantity of floating cars and "relation model between road overlay rate and update cycle" are designed and advanced for the first time so as to solve problem of low reliability in practical application of technology for floating car information collection. Practicability and validity of the two are also validated through concrete examples.Thirdly, information origins of integrated information service system for public traveling of Chengdu city are researched deeply. Aimed at the isomerous character and requirement of information sharing, "system architecture model based on local central database and web service" and scheme of information sharing among isomerous traffic information systems based on SOA technology are brought forward for the first time. Through the exploitation of public traveling information system of Chengdu city, problems of data sharing and operation application among different systems are solved successfully. At the same time, comparing with other schemes, architecture based on SOA is excellent at the aspects of lower system coupling, better expansibility, independent of platform and exploitation language, which is a good choice to solve problems for integrating of isomerous systems.Fourthly, through research of key technologies of data disposition of traffic traveling information and information publishing of Chengdu public traveling system, "algorithm of multi-pattern route layout based on ant colony and experts systems" and "two service modes of traffic information—pushing/pulling " are brought forward for the first time. At the same time, "intelligent model of pulling service based on Neural Network and expert system" is also advanced first.