It is discovered that a river occurs to wa-ver along a river axis at initial stage, then the axis bends gradually; due to Coriolis Force action, the center ofcurvature is usually located at the south side of the river and the bending reach of south side develops quickerthan its north side; as a result, the bending radius of axis reduces.

Analyses of the curvature radius of the cam outline in constant flow reciprocating pump;

Quantitative relation between decomposition rate and curvature radius of hump on phase diagram during binary chemical compound melting;

Linearity measuring mechanism of the curvature radius of sphere lens;