Aiming at the irregular polygon charac- teristic of geologic units,polygon partition is proposed to extract gravity and magnetic data.

The author uses the principle of coordinate trnsformation to develop a new equation for the calculation of the number of transfer units in a packed distillation column.

By reasonably dividing the end surface area of gear s tooth, presentation of big blunt angles among end surface meshes is avoided effectively and element quality is improved by employing the algorithm.

With a thermodynamic system of a cogeneration power plant serving as a target investigated,using basic theory of engineering thermodynamics,thermodynamic cycle was divided into different mass units based on particular analysis of thermodynamic cycle characteristics.