Machine Learning Techniques for Automated Tremor Detection in the Presence of External Stressors

In this study tremor data of 25 subjects (Senile tremor = 5, Alcohol induced tremor = 9, Healthy individuals = 11) were collected using a wearable device consisting of five Inertial Measuring Units (IMUs) and an embedded optical sensor. The subjects were made to draw the Archimedes spiral under the influence of external stressors. Features were extracted from measured acceleration data and also from an optical sensor. Using the selected features few supervised machined learning algorithms were explored for automatic classification of tremor. Performance matrix used to evaluate the classifier was accuracy, recall, and precision. It is observed that the algorithms are able to accurately classify healthy, senile tremor and alcohol induced tremor.

Studi Eksperimental Sistem Pengarah Aliran Pada Turbin Hidrokinetik Archimedes Spiral

Archimedes Spiral Turbine has characteristic of blade which can catch water flow well. It uses two force concepts, i.e. drag and lift forces. Flow direction change greatly influences Archimedes Spiral turbine performance. Therefore, it needs flow direction system in form of truncated cone and tail vane. Archimedes Spiral turbine with flow direction system generated Cp value of 0,19–0,22 and TSR value between 1,76–1,85. Torque value obtained is between 0,013–0,017 Nm on RPM value range of 28,64–33,60. Limitation between truncated cone with Archimedes Spiral turbine blade causes vortex flow at the back of blade to decrease. Truncated cone addition can enlarge flow catchment force. When flow speed captured by Archimedes Spiral turbine increase, resulting in a compressive force on enlarged. The addition of tail vane capable of passing the flow vortex is elongated to downstream. The flow of vortex which is passed on inhibits the rotation of the turbine blades and result in a compressive force on the turbine is enlarged. Compressive force on blade which grows bigger causes torque value to increase as well. The increasing torque value causes drag force concept used in Archimedes Spiral turbine with flow direction system higher than lift force concept.