There are many experiential sound speed formulae now.

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.

An approach to find empirical formula for mine ventilation using rough set theory;

Application of empirical formula to describe effective permittivity of microwave-assisted chemical reaction;

Analysis of variability of empirical formulas for foundation bearing capacities;

Distribution of droplet diameters and the spline of their empirical equation for spiral nozzle;

The empirical equation of milling force is achieved by regression analysis method,and proved to be tried.

The dynameter is of the model 9257B, made by Kistler Corporation of Switzrland By the data obtained from the experimental study and the use of statistic method, an empirical equation of threedimensional burnishing force on an aluminium alloy(LY12) workpiece with a cylinderical polycrystalline diamond tool is es.

The crude oil volume factors for five different complex petroleum fluids were calculated at different pressures by the new method,the Standing experience formula and Vazquez-Beggs experience formula.

In this paper,we chosed some experience formulas from some coal experts to check up our measured calorific values of 48 anthracites, and found we can't give the correct appraising for the measured calorific values only by one experience formula because the errors distribution from different experience formulas have large difference.

By contrasting the PVT parameters between observed and calculations through experience formula,PVT parameters calculating experience formula which suit to geology conditions of the peripheral zones in Daqing oilfields is found.