The bubble shape is changed gently because of the difference between radius of geometric curvature and radius required to equalize normal stress.

由于几何曲率半径和平衡正压力所要求的半径有差别，气泡形状要缓慢地变化。

youdao

Research the basal concepts and formulas of coordinate conversion, the formulas of the radius of curvature in a normal section, the meridional length and the latitude of pedal are given.

对坐标转换的基本概念和基本公式做了研究，给出了法截线曲率半径、子午线弧长和底点纬度的解算公式。

youdao

Using the changing rate of maximum feed-rate as a threshold, the surface of the part is divided into different areas according to the values of normal curvature radius.

以最大工作进给速度的变化比率为阈值，把零件表面的法曲率半径划分为不同的区域；

youdao