Study of K-Nearest Neighbour classification performance on fatigue and non-fatigue EMG signal features

© 2020, Science and Information Organization. For our body to move, the muscle must activate by relaxing and contracting. Muscle activation produces bio-electric signals that can be detected using Electromyography or EMG. The signal produced by the muscle is affected by the type of contraction done by the muscle. The eccentric contraction generating different EMG signals from concentric contraction. EMG signal contains multiple features. These features can be extracted using MATLAB software. This paper focuses on the bicep brachii and brachioradialis in the upper arm and forearm, respectively. The EMG signals are extracted using surface EMG whereby electrical pads are placed onto the surface of the muscle. Features can then be extracted from the EMG signal. This paper will focus on the MAV, VAR, and RMS features of the EMG signal. The features are then classified into eccentric, concentric or isometric contraction. The performance of the K-Nearest Neighbour (KNN) classifier is inconsistent due to the EMG data variabilities. The accuracy varies from one data set to another. However, it is concluded that non-fatigue signal classification accuracy is higher than fatigue signal classification accuracy

Effects of Chinese University Students’ Academic Achievement and Course Satisfaction on Their Ratings of Teachers’ Instruction

The purpose of this study was to investigate the relationships between students’ perception of teachers’ instruction, course satisfaction, and student academic achievement. The data were extracted from TsingHua Education Online (THEOL) Management Information System (MIS) and analyzed via structuring equation modeling. The researchers hypothesized student ratings of instruction were affected by their achievement and course satisfaction. The results confirmed a positive relationship between course satisfaction and student ratings of instruction, but did not find direct effect of student academic achievement on their ratings of teachers’ instruction. This suggests that course satisfaction is a more important factor than academic achievement when students rate their teachers’ instruction. The finding also suggests that the student ratings of instruction may be an objective and acceptable performance indicator for teachers’ instruction in a course

Analytical time-domain model for radio over free space optical (RoFSO) systems considering the scintillation effect

This work was supported by the World-Class University (WCU) Program through the National Research Foundation of Korea (R31-10026), and Grant K20901000004-09E0100-00410 funded by the Ministry of Education, Science, and Technology (MEST).An analytical time-domain model is presented to analyze a radio over free space optical (RoFSO) system considering the scintillation effect with a log-normal distribution. This analytical model uses a dual-drive Mach-Zehnder modulator (DD-MZM) and photodetector (PD) for typical optical double sideband (ODSB) and single sideband (OSSB) signals. We show the output current of PD as a function of the summation of each frequency component in time domain. Finally, we calculate the received signal power with respect to the power spectral density (PSD) and derive a closed-form average bit error rate (BER) performance.Peer reviewedFinal Accepted Versio