Second, a criterion of the stability of relative motion for the nonholonomic mechanical systems was obtained by using the equationofvariation of energy.
其次，基于能量变化方程，给出了非完整力学系统相对运动的稳定性的一个判据；
2
The mass transfer equation was introduced into heat transfer model of falling film evaporation. The radial velocity, mass diffusion coefficient and variation of film thickness were taken into account.
Derives an equation set to reveal the influence of water flow variation on temperature of the heated room and permitted fluctuation of the hydraulic imbalance degree of pipeline.