Fault Diagnosis of Subway Traction Motor Bearing Based on Information Fusion under Variable Working Conditions

Figure 12

Four models of derivation. (a) The test set sample is larger than the upper limit of the training set sample interval. (b) The test set samples are in the training set sample interval. (c) The test set sample is smaller than the training set sample interval lower limit. (d) The sample interval of the test set is equal to that of the training set.

(a)

(b)

(c)

(d)