The practice application expresses that effective modalmass could be helpful to find natural frequency and vibration shape.
应用表明用有效模态质量进行模态识别，可以有助于找到尾轴架系统的固有频率和振型。
2
The severe numerical instability in complex frequency modalmass identification from frequency response function makes it difficult to identify physical parameters.
利用频响函数识别复频率模态质量存在着严重的数值计算不稳定性，给物理参数的识别造成困难。
3
By modal stiffness matrix, modalmass matrix and modal frequency, shaft units of simulator is designed. The former three steps natural characteristics are identical with the real units'.