Rotor-System Log-Decrement Identification Using Short-Time Fourier-Transform Filter

<table class="figure-group"><tr class="fig-image" id="a"><td><object data="https://static.hindawi.com/articles/ijrm/volume-2015/809785/figures/809785.fig.0015a.svgz" name="809785.fig.0015a" type="image/svg+xml"></object></td></tr><tr class="fig-caption"><td><b>(a) </b>Without STFT filtering  (Nat. Fre. = 68.4 ± 0.08 Hz; Log Dec. = 0.348 ± 0.004)</td></tr><tr class="fig-image" id="b"><td><object data="https://static.hindawi.com/articles/ijrm/volume-2015/809785/figures/809785.fig.0015b.svgz" name="809785.fig.0015b" type="image/svg+xml"></object></td></tr><tr class="fig-caption"><td><b>(b) </b>With STFT filtering (Nat. Fre. = 68.4 ± 0.09 Hz; Log Dec. = 0.350 ± 0.004)</td></tr></table>

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International Journal of Rotating Machinery

fig15

Figure 15

Figure 15: Rotor-System Log-Decrement Identification Using Short-Time Fourier-Transform Filter 