principle of virtual work

• 虚功原理

principle of virtual work的用法和样例：

例句

1. Then, the principle of virtual work is used to derivate the equilibrium condition of CM.
   在以上基础上，应用虚功原理，推导出柔性机械稳态的条件。
2. On the principle of the deformation work this paper words out a very simple method for approximate calculation of the extrusion force in the metalic plastic extrusion processes.
   运用变形功原理，推导出求金属塑性挤压过程中挤压力的一种极其简捷的近似计算式。