Estimation of first empirical frequency confidence region of historical floods recorded at Tian e Hydrometric Station;

In frequency computation of hydrology, empirical frequency has a significant effect on the results of the curvefitting method.

Programming with VB6 for hydrologic experimental frequency curve-fitting software;

For application in planning and design,it is necessary to retrieve the burst flow volume to check the reasonableness of the flood calculation,and to estimate the experimental frequency of the peak and flood volume of the extraordinary floods occured in Nenjiang River and Songhua River in 1998.

In order to correctly evaluate the trophic state of a lake and then to establish a scientific basis for the prevention of lake eutrophication, a lake eutrophication stochastic assessment method (LESAM) by using empirical frequency curve (EFC) is proposed.

This paper, after analyzing the theoretical bases of three plotting position formulae, uses statistics test method to choose the best one for P Ⅲ distribution.

The empirical mode frequency decomposition(EMFD) is presented based on the empirical mode decomposition (EMD).

With the cracked wrapping strip replaced on the35stage rotor,frequency test was run with the turbine vanes,and the vane wrapping strip was adjusted according to the test results on the35stage rotor so that the frequency spectrum of its vanes was basically in agreement with that of.