Article human 5 signal noise ratio Humans 4 adult 4 female 4 machine learning 4 male 4 mathematical model 4 physical activity 4 Walking 3 electroencephalography 3 human experiment 3 normal human 3 random forest 3 walking 3 Classification (of information) 2 Decision trees 2 Electrocardiography 2 Support vector machines 2 Support vector regression 2 Wearable Electronic Devices 2 Wearable sensors 2 algorithm 2 artificial neural network 2 breathing 2 classification algorithm 2 comparative effectiveness 2 continuous wavelet transform 2 cross validation 2