No abstract

Facial electromyography is myoelectric signals that formed by human facial muscles. This signal can be acquired by attaching an electrode to the facial muscle that has been connected with an electromyography sensor. When human say certain words, the articulation muscles contract and facial electromyography signals appear in the muscles. This study aims to recognize patterns in facial electromyography signals by classifying signals using naïve bayes and learning vector quantization classifier. Feature extraction used one-dimensional discrete wavelet transforms. Wavelet transform type used wavelet daubechies2 level 5. The transformation produces a level 5 approximation coefficient called a5 and five detail coefficients called d1, d2, d3, d4, and d5. The result of this study show that the average classification accuracy for ho neuk jak sentence using naïve bayes and LVQ classifier was 62.5% and 92.5% respectively. The average classification accuracy for ja’ word using naïve bayes and LVQ classifier was 70% and 92.5% respectively. The average classification accuracy for ja’ wo sentence using naïve bayes and LVQ classifier was 52.5% and 90% respectively. The average classification accuracy for pane word using naïve bayes and LVQ was 70% and 90% respectively. The average classification accuracy for soe word using naïve bayes and LVQ classifier is 85% and 95% respectively. Thus, this study shows that when humans say the words, facial electromyography signals that appear on facial muscles difference for each subject.

Power electronics is a field of science that studies and discusses electronics applications related to large-power electrical equipment, one of the sub-subject studied is the AC to DC converter such as a three-phase half-wave controlled rectifier with a resistive load in which output voltage can be controlled by adjusting the triggering delay angle of gate SCR. The components used include a three-phase step-down transformer where the output is used as a reference signal to determine the starting point (30o) and the endpoint (150o) of triggering delay angle, it is also used as a power source for the system, LM393 is used as a comparator between three-phase rectifier (Vd) with DC voltage (Vreference), likewise to compare triangular waves with DC voltages that resulting from changes in the voltage on the potentiometer in order to control the triggering delay angle (α) of SCR. The first step that must be taken to make measurements using an oscilloscope is to determine the ton and toff values for each angle by rotating the potentiometer on the comparator circuit and then measuring the average output voltage (Vo),  determination the triggering angle in this research is still done manually so that the measurement results compared to the calculation has a difference this is due to the level of accuracy in observing the oscilloscope, on the other hand, the three-phase transformer and sources used are not in ideal conditions.