经过我军测绘工作者历时10年艰苦奋战,我国第一个大型地形数字信息工程——全国1:25万地形图数据库建成。 运用现代信息技术建设全国1:25万地形图数据库是一项规模浩大的跨学科系统工程,需要解决地图要素分类分级、图形拓扑结 After 10 years of painstaking efforts by our army mapping workers, the first large-scale digital terrain information project in China - the 1: 250,000 topographic map database in China was completed. The use of modern information technology to build the national 1: 250,000 topographic map database is a vast scale of interdisciplinary systems engineering, need to address map classification and classification of elements, graphics topology