短語詞組短語drill string longitudinal vibration 鉆柱的縱向振動string g vibration 弦振動string free vibration 弦自由振動drill string lateral vibration 鉆柱橫向振動drill string vertical vibration 鉆柱縱向振動drill string torsional vibration 鉆柱的扭轉(zhuǎn)振動piano string vibration 鋼琴弦振動string vibration equation 弦振動方程 返回 string vibration