他使用了出现频率轨迹的另一个版本。

He used a version of the frequency trick.

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用本文提出的方法，不仅可以求得系统的固有频率、振型、动态响应，还可以模拟轴上各点的涡动轨迹。

Using this method not only the natural frequencies, mode shapes, dynamic responses but also the whirl orbits of the rotor system can be obtained.

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利用该系统可对电子束扫描轨迹、扫描频率以及加热区域电子束能量密度的分配进行离线编辑和在线调节。

The EB scanning track, scanning frequency and energy density distribution at heating zone could be programmed off-line and adjusted on-line.

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