Based on the spatial distribution rule of water quality in rivers, a method to evaluate the influence of multi point sources on river water quality was established using geostatistical method for constructing spatial statistic structure of variables and superposition principle.

By employing magnetic field distribution in the form of cylindrical coordinates and superposition principle, the general expression for tne magnetic field of Helmholzs coils is achieved, with elliptic integrals.

When certain part of the bcamdeformates independently, then the displacement of the cross section can be calculated repidly andaccurately with the superposition principle of mechanics.

Mathematics base of principle of superposition and its application in physics;

Moreover,in the light of the principle of superposition,the composition of above mentioned profiles vertical each other in two directions is carried out and the imitative diffraction patterns ob.

The argumentation of introducing Schrdinger equation,the explanation of the principle of state superposition and the statement of the problems about bound states,continuous and discrete spectrum are improved.

It deduces the permanent deformation calculation of single-rutting specimen under cyclic loading based on the integral-type creep constitutive equation (Boltzmann superposition principle of integral-type).

Basing on the basic principle of element dynamic analysis, the calculation formula of seismic acceleration of the sole rock under the condition of known ground seismic acceleration was derived and the calculation method of seismic acceleration of the sole rock was proposed by using of the principle of model superposition and Fourier transform.