.基于GIS的城市道路交通流信息发布系统应用研究*

根据基于GPRS/GPS/GSM浮动车交通流信息采集系统实时采集的交通流瞬时速度、路段速度、车辆定位等信息，借助面向对象技术、GIS技术、数据库技术设计、开发了基于GIS的城市交通流信息发布系统，系统采用数据库中的存储过程技术处理海量交通流信息与GIS信息等数据表的多表连接，实现了高效率信息查询，并融合GIS专题地图技术和数据库技术实现浮动车辆历史轨迹动态回放、交通流路段速度查询、可视化显示。开发的系统在天津市部分路段进行试验，系统能稳定、可靠地实现交通流信息发布，并能快速有效查询城市道路交通流信息及识别城市道路网络路况瓶颈，可以辅助交通管理者进行交通管理决策。

Applied research on urban road traffic flow information publishing system based on GIS

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.