Applied research on urban road traffic flow information publishing system based on GIS
.基于GIS的城市道路交通流信息发布系统应用研究*

According to instantaneous velocity, link velocity, vehicle positioning information of the floating car information collection system based on GPRS/GPS/GSM, urban road traffic flow information publishing system is designed and developed with the technology of objected-oriented, GIS, and database. Stored procedure of database is used to dealing with the inner-join interrelation of multiple database table between large-scale traffic flow information and geographic information. And so, the high performance of information query is guaranteed. Moreover, not only the historical driving trace of floating car can be dynamically played back, but also car link velocity can be queried and visualized by using thematic map and database technology. Finally, the system is of stable and reliable during the application to the trial of partial urban roads in Tianjin City. And that urban road traffic information can be queried in high speed, and the bottleneck of urban road traffic network can be easily recognized. Therefore, traffic manager can be aided to make decision to dealing with traffic jam.