SG	Savitzky–Golay Smoothing
FD	First-Derivative Transformation
SD	Second-Derivative Transformation
MSC	Multiplicative Scatter Correlation
PLSR	Partial Least Squares Regression
BPNN	Back Propagation Neural Network
RF	Random Forest Regression
KNN	K-Nearest Neighbors
$R^2$	coefficient of determination
nRMSE	Normalized Root Mean Square Error
SMOGN	Synthetic Minority Over-Sampling Technique for Regression with Gaussian Noise
DA	Data Augmentation
GA	Genetic Algorithm
SVM	Support Vector Machine
RFC	Random Forest Classification
MLP	Multi-Layer Perceptron