摘要
将不同坐标系或投影带地图纳入同一个系统或拼接的较好方法是构建基于地理坐标的数字地图,在基于地理坐标的数字地图的量算中,由于参考椭球面与地球自然表面之间有一定的距离,导致椭球面上的计算值与地球自然表面的实测值有一定的差异.考虑到投影面距离地球自然表面越近,投影面上的计算值也就越接近地球表面的实测值,因此可采用建立抵偿坐标系的方法建立地图量算模型.用于投影的抵偿面是计算对象所在的平均高程面,用于投影的中央子午线是计算对象所在的平均经线,因此计算结果最接近实测值.该方法(模型)比较适用于对精度要求较高且工作范围不大的区域.
To construct a digital map based on geographic coordinates is a better method to bring digital maps in different coordinate systems or projection zones into one system or joint them. In the measurement of digital maps based on geographic coordinates, the deviation between the reference ellipsoid surface and the earth＇s surface results in the discrepance between the calculating value on the reference ellipsoid surface and the real surveying value on the earth＇s surface. Because a projection plane is more close to the earth＇s surface, the calculating value on the projection plane is more close the real surveying value on the earth＇s surface. Therefore, the measurement model of digital maps may be set up by establishing a compensation coordinate system. In this model, the compensation projection plane is the surface of average elevation of calculated objects, and the central meridian of projection is the average longitude line of calculated objects, so the calculating result is most close to the real surveying value. This model （method） is more suitable for the regions with a small area and a requirement of high measuring accuracy.
出处
《西南交通大学学报》
EI
CSCD
北大核心
2005年第3期318-321,共4页
Journal of Southwest Jiaotong University
基金
陕西省教育厅专项科研计划项目(01JK179)
关键词
数字地图
地理坐标
地图量算
抵偿坐标系
digital map
geographic coordinate
map measurement
compensation coordinate system
