For rapidly rotating stars, the effect of gravity darkening on the equivalent width (EW)of spectral lines is very small, even when the rotation velocity is close to the critical velocity.

To analyse the color image of driver s face taken by CCD camera under obscure conditions,the image noise jamming is eliminated first by erosion in combination with dilation operation,and the threshold processing is used for the grey level differences in the image to select preliminarily the threshold value of grey level.