Rockburst Prediction Based on the KPCA-APSO-SVM Model and Its Engineering Application

Table 1

Commonly used kernel functions.

Kernel function type	Kernel function expression
Linear kernel function (LKF)
Polynomial kernel function (PKF)
Radial basis function (RBF)
Sigmoid kernel function (SKF)
Gaussian kernel function (GKF)

Note. c, a, , and are manually set parameters, q is the degree of a polynomial, and σ is the gauss kernel bandwidth.