The Angle subtended at the center of a sphere by an area on its surface numerically equal to the square of the radius.

在单位半径的球体中心对球表面上的投影面积所张的角。

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Having tested and analyzed the bicycle joints, the authors propose a new design method with which CAM is designed as an equal radius CAM at its working portion.

本文通过对自行车接头的分析和试验，提出设计工作部分等半径凸轮的方案。

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