balance condition的用法和樣例：
例句
- The condition of equilibrium of the member requires that the pair of forces coming from the joints must be equal and opposite.
元件的平衡條件要求來自連接點的一對力必須大小相等，方向相反。 - The coupling matrix is given by the interface displacement compatibility condition and the interface force equilibrium condition.
組合矩陣由交界面位移連續條件和交界面力的平衡條件給出。
