Deep learning Convolutional neural network Face recognition AlexNet Artificial neural network (ANN) Automated applications Body language COVID-19 Color histogram Convolution Convolutional neural networks Data augmentation Developed applications Drowsiness Emotion recognition Engineering education Face expressions Facial Expressions Fatigue GoogLeNet Gray-Level Co-Occurrence HOG Herbal plant recognition Hu-histogram LBP Leaf recognition Learning approach Learning habits factor Learning technology Maize leaves