The Contact State Monitoring for Seal End Faces Based on Acoustic Emission Detection

Table 2

Features extraction.

Code name	Feature	Equation
	Root Mean Square (RMS)
	Energy Variance (EV)
	Peak to Average Ratio (PAR)
	Peak Variance (PV)
	Absolute Skewness (AS)
	Center Frequency (CF)
	Frequency Variance (FV)