1-D	One-dimensional
2-D	Two-dimensional
AI	Artificial intelligence
ANOVA	Analysis of variance
CNN	Convolutional neural network
DL	Deep learning
EMD	Empirical decomposition mode
GAN	Generative Adversarial Network
HR	Heart rate
ICU	Intensive care unit
K-fold CV	K-fold cross-validation
LOOCV	Leave-one-out cross-validation
LSTM	Long short-term memory
MA	Motion artifact
ML	Machine learning
mRMR	Minimum redundancy–maximum relevance
OCSVM	One-class support vector machine
PCA	Principal component analysis
PPG	Photoplethysmogram
RFE	Recursive feature elimination
RMSE	Root mean square error
ROC	Receiver operating characteristic
RSL	Reference signal-less
SOM	Self-organizing map
SQI	Signal quality index
SpO2	Peripheral oxygen saturation
SVM	Support vector machine