SAE	Stacked Autoencoder
RUL	Remaining Useful Life
GRU	Gated Recurrent Unit
HMM	Hidden Markov Model
CNN	Convolutional Neural Network
CNN Block	Convolutional Neural Network Block
PCHIP	Piecewise Cubic Hermite Interpolating Polynomial
PECG	PCHIP-Enhanced ConvGRU
PCC	Pearson’s Correlation Coefficient
CNC machine	Computerized Numerical Control Machine
MGRU	Multi-head gated recurrent unit
PCA	Principal component analysis
ANN	Artificial Neural Network
SVM	Support Vector Machine
GPR	Gaussian Process Regression
RNN	Recurrent Neural Network
DNN	Deep Neural Network
ReLU	Rectified Linear Unit
EMA	Exponential Moving Average
MAE	Mean Absolute Error
RMSE	Root Mean Square Error
MAPE	Mean Absolute Percentage Error