A simple method of analysis is presented for calculating the deflection curve, elastic critical load and fundamental period of single and coupled shear wall structures with either uniform or variable thickness.

This paper includes an investigation on a model test for dynamic soil-structure interaction,the approximate effective fundamental period and the limit of considering the dynamic soil-structure interaction.

Empirical formulas for the relationships of the fundamental period ratio and damping factor with structure-to-soil stiffness ratio and mass ratio are presented.

The article expounds the nature of periodic function and proves the existence of the base period of the continuous periodic function.

The results show that when TN/TP changes within the range of 25∶1~12∶1,the period of algae production reduces and quantity of algae production increase.

Based on the fact that production cycle of the evaporator (NaCl 150,000tpa) of System No.

Markets develop daily, commodity sales are becoming into an unascertained information, and markets are diversified, enterprise production cycles tend to be unascertained.

The calculation of the parallel coefficient when defining the production cycle of technological stage,and determination of the subjective coefficient when de.