ELMSS	Extreme learning machine of single-track scanning
ELMPS	Extreme learning machine of plane scanning
MRR	Material removal rate
BP	Back propagation
RBF	Radial basis function
ANN	Artificial neural network
LP	Laser power
PF	Pulse frequency
SS	Scan speed
LS	Line spacing
D	Depth of ablation
W	Width of ablation
Ra	Surface roughness
GA-ELMSS	ELMSS optimized by genetic algorithm
GA-ELMPS	ELMPS optimized by genetic algorithm