Table 4.

Working condition feature table.

Feature	Name	Describe
Time domain feature	mean	The mean value of data
	med	The median value of data
	std	The standard deviation of data
	mad	The median absolute value of data
	quantile1	The 25th percentile of signal
	quantile2	The 75th percentile of signal
	iqr	Interquartile range
	skewness	The skewness of time signal
	kurtosis	The kurtosis of time signal
	var	The variance of time signal
	entropy	The entropy value of signal
	sepctral entropy	The sepctral entropy value of signal
Frequency domain feature	maxfreq	The maximum frequency of frequency features
	maxval	The maximum value of frequency features
	maxratio	The maximum ratio of frequency features
	peak	The main peak of autoregression features
	height	The second peak height of autoregression features
	position	The second peak position of autoregression features
	spwf	The spectral power features in 5 adjacent frequency