The Method for Determining Optimal Analysis Length of Vibration Data Based on Improved Multiscale Permutation Entropy

<div>Vibration signal and permutation entropy value change at the pump opening moment. (a) Time course graph of pipeline vibration. (b) Diagram of entropy change under different sequence lengths. Note: the black line is the change of the entropy value of the subsequence <i>N</i> = 1000; the red line is the change of the entropy value of the subsequence <i>N</i> = 2000.</div>

Shock and Vibration

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Figure 9

Figure 9: The Method for Determining Optimal Analysis Length of Vibration Data Based on Improved Multiscale Permutation Entropy 