“…The window width was 128 ms and the sliding distance was 78 ms. We selected 13 specific features including zero-crossings (ZC), root mean square (RMS), mean absolute value (MAV), waveform length (WL), variance (VAR), slope sign change (SSC), Willison amplitude (WAMP), mean value (MEAN), the standard value (STD), mean frequency (MNF), median frequency (MF), mean power frequency (MPF), and Lempel-Ziv complexity (LZC). The ZC, RMS, MAV, WL, VAR, SSC, and WAMP have commonly used time-domain features (Hua et al, 2020 ; Qu et al, 2020 ; Wu et al, 2020 ; Duan et al, 2021 ). In addition to these parameters, we further calculated the MEAN and STD, so that the time-domain features reached nine.…”