If the processing basis ,measuring basis misalign with the design basis,a false waste zone will occur on the part s dimensions in mechanical processingUsing extremum method to determine the false waste zone can decrease the product costs,guarantee the processing accuracy

A new centre-extracted method that combines genetic algorithm with extremum method is proposed in this paper.

This paper suggests an extreme value method to calculate the working sizes of injection mold shaping parts, and explains the application of this method in practical calculations.

In the experiment for measuring ultrasonic velocity,the accuracy in measureing wavelength by extreme value method or phase method are discussed,through experiment and theory analysis,it is proved that accuracy of phase method is better than that of extreme value method in measure wavelength at one time,it is better to measure an extreme value rate point than a extreme value point.

This paper proposed a new combined assessing based on extreme value method,using data from medical universities journals of Institute of Scientific & Technical Information of China,in order to solve the problem of results dis-agreement by different assessing methods in academic periodical evaluation.