“…Data capturing can be conducted by various wearable sensors, such as an accelerometer [3,14,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32], a gyroscope [15,21,28,31,32,33,34,35,36], a magnetometer [19,34,35,36,37,38], an Electrocardiogram sensor (ECG) [31,39], a Global Positioning System (GPS) sensor [22], Electromyography sensor (EMG) [8,40,41], etc. Besides wearable sensors, data collection can be conducted using non-contact sensing [4,42,43,44], and with various sensors that are integrated into smartphones [45,46,47,48,49,50]. Many problems during data collection from wearable sensors may occur.…”