“…In the past years, many vibration signal processing techniques, such as wavelet packet transform [5], ensemble empirical mode decomposition (EEMD) [6], local mean decomposition (LMD) algorithm [7] and Variational mode decomposition (VMD) algorithm [8], higher order energy operator fusion [9], Quaternion singular spectrum [10], blind source separation method [11], low-rank matrix approximations [12], sparse representation [13,14] and deep learning [15], etc., have been developed to extract the fault features from measured signals for bearing fault diagnosis. Currently, the turntable -factor wavelet transform (TQWT) was original proposed by Selesnick, and the advantage of TQWT is that the -factor is easily and continuously adjustable [16,17].…”