基于WebGIS的GPS车辆监控调度系统的设计与实现

本文介绍了1个基于B/S 模式的GPS车辆监控调度系统的设计思想及实现方案,此系统突破了传统网络系统的功能局限,使WebGIS技术与短信服务技术（SMS）进行无缝集成,实现网上作业.系统采用了1种新颖的WebGIS的设计构想--利用DCOM/ActiveX技术并采用三层结构模式：将矢量地理信息等需要经常变动的信息由数据库服务器集中管理,这样地理信息的更新维护就很方便;将基础性、全局性的处理交由应用服务器执行,而对数据量较小的简单操作则由浏览器端自定义的ActiveX控件直接完成.系统中用来在浏览器端显示的地图信息突破了传统的静态压缩图片的传输方式,而是深入到服务器端MapX控件中的电子地图图层内部提取的关键型矢量数据,然后在浏览器端重组和成完整的地图,这种方式大大缩减了网络通信量,进而有效地提高了系统的响应速度,能够快速地进行海量地图的浏览显示.此外,系统的浏览器端不需要配备昂贵的专业GIS软件,降低了系统成本,同时也节省了维护费用.

THE DESIGNMENT & REALIZATION OF GPS VEHICLE MONITOR & DISPATCH SYSTEM BASED ON WEBGIS

The design idea and realization scheme of a GPS vehicle monitor and dispatch system based on Browser/Server mode was introduced . This system breaks through the functional restriction in the traditional network system, integrated the WebGIS technique with SMS zeamlessly, and realized working in network. A novel design conception of WEBGIS has been adopted in this system, which used the DCOM/ActiveX technology and the B/S three-layer mode. the mutable information such as the vector data and so on were managed on the database server, it is convenient for the update and maintenance of the geographical information, the basic and global process is executed on the application server, however, the simple operator of the small data can be directly processed by the custom ActiveX control at the browser end. The map information at the browser end is pivotal vector data, which breaks through the traditional mode of transmiting the image data, however, distills in the MapX control at the server end and recombines at the browser end. Thus it so effectively reduces the data transmission amount and improves the response speed that it can browse and display the great capacity of map quickly. In the other hand, the browser end doesnt need expensive and special GIS software, so save the cost and the maintenance expenditure of the system.