Table 3: The used variable in this paper.

VariableDefinition

p(x) The probability density function from the observed vibration signal’s amplitude
x The vibration amplitude
Waveform index
Impulse index
Margin index
Peak index
Kurtosis index
A dimension parameter named as root of mean square(RMS)
The sensitivity of the th kind of nondimensional index detector to the jth kind of failure
The effective information preserved in the total feature information of a dimensionless index to generate a mature immune detector
The diagnosis capability factor of the kind of th dimensionless index immune detector to the kind of jth fault