摘要
就中国建立现代大地测量平面基准而言,目前主要焦点在于是否采用地心3维坐标系统,也就是在中国这样一个大国进行这一坐标系更换的必要性和可行性的论证。在必要性方面重点讨论下面几个方面的问题:中国大地坐标系统和大地坐标框架的现状和问题;中国地心3维坐标框架应具有的特点;中国采用地心3维坐标系统的优点;以及建议采用何种大地测量基本常数。可行性是中国能否采用地心3维坐标系统的核心问题。只讨论了可行性可能涉及的4个问题中的2个,一是必须具备有足够数量,适宜密度,动态的高精度坐标框架来实现地心3维坐标系统;二是坐标系统更换对全国千万张现有各类地图,特别是地形图的影响,其中包括地面点经纬度和高斯平面坐标的变更幅度,地图上两点间连线(包括图廓线)的方位和长度变化等。 收稿日期:2003 08 05作者简介:陈俊勇(1933 ),男,浙江宁波人,中国科学院院士,主要研究方向为天文大地测量。
So far the Chinese modern geodetic datum as concerned, the focus is whether the geocentric three dimension (3D) coordinate system should be employed in China or not. As a matter of fact it is essentially a problem of necessity and feasibility for a geodetic coordinate system updating in a large developing country like China. The following topics in necessity are discussed: The situation and problems in Chinese existing geodetic coordinate system and its frame; The characteristics of a Chinese modern geocentric 3D coordinate frame; The advantages for a geocentric 3D coordinate system if it is employed in China. What kind of the Geodetic Fundamental Constants should be taken for a Chinese modern geocentric 3D coordinate system.The feasibility is the key point for updating a Chinese coordinate system. Only two among the four issues concerning the feasibility are discussed. One is that a Chinese geocentric 3D coordinate frame with enough points, suitable density, high accuracy, and dynamic is the necessary condition to realize the Chinese geocentric 3D coordinate system; The other one is the influences on the current existing millions various Chinese maps, especially the topographic map, caused by the change of the coordinate systems. Such as the changes of latitude, longitude, and Gauss plane coordinates of the surface points and their projection on the map, as well as the variation of the orientation and the length of the lines between the points on the map (including map outlines).
出处
《测绘学报》
EI
CSCD
北大核心
2003年第4期283-288,共6页
Acta Geodaetica et Cartographica Sinica
关键词
平面基准
坐标系统
坐标框架
坐标系统更换
大地测量基本常数
地图
geodetic datum
coordinate system
coordinate frame
replacement of coordinate system
geodetic fundamental constants
map
