datum surface

基本解释

Select planar surface or datum plane.
任意选择一个平面。
In order to establish the datum surface before precisely grinding inner surface, it is necessary to reconstruct of the free curved surface according to the measurement data.
加工前实际内廓型面是按需去除的基准，故必须先对内廓面进行测量，再根据测量型值点重构出内廓型面，建立精密修磨的相对参考基准。
A method for deriving the smoothed ground surface from CMP datum of static correction is given to form a common datum for velocity spectrum, time-depth conversion and depth migration in depth domain.
本文还给出了根据（静校正的）CMP基准面计算地表圆滑面的方法，统一了深度域中速度谱、时深转换和深度偏移的基准面。