seconds in each file; 3) seven inner ring fault datasets sampled at 48828 Hz for three seconds in each file; 4) some other datasets which are not used in this paper (more detailed information can be referred to the website of MFPT datasets [@MFPT]). In Table \[Tab\_2\], one health state bearing and two fault bearings including the inner ring fault and the rolling element fault are classified into ten categories (one health state and nine fault states) according to different loads.

\[Tab\_2\]

    Fault Mode                   Description:
  -------------- ---------------------------------------------
   Health State      Fault-free bearing working at 270 lbs
   Outer ring 1   Outer ring fault bearing working at 25 lbs
   Outer ring 2   Outer ring fault bearing working at 50 lbs
   Outer ring 3   Outer ring fault bearing working at 100 lbs
   Outer ring 4   Outer ring fault bearing working at 150 lbs
   Outer ring 5   Outer ring fault bearing working at 200 lbs
   Outer ring 6   Outer ring fault bearing working at 250 lbs
   Outer ring 7   Outer ring fault bearing working at 300 lbs
   Outer ring 1    Inner ring fault bearing working at 0 lbs
   Inner ring 2   Inner ring fault bearing working at 50 lbs
   Inner ring 3   Inner ring fault 