http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
곽태수(Tae-Soo Kwak),남우철(Woo-Chul Nam),김유영(Yoo-Young Kim),김경년(Kyung-Nyun Kim),이용철(Yong-chul Lee) 한국기계가공학회 2009 한국기계가공학회 춘추계학술대회 논문집 Vol.2009 No.6
This study has been focused on properties of mirror surface grinding technology by ELID(ELectrolytic In-process Dressing) for structural ceramics using in high precision structural parts on semi conductor manufacturing processes. ELID grinding is an excellent technique for mirror grinding of various advanced metallic or nonmetallic materials as hard to machining materials. The experimental studies have been carried out to get mirror surface for grinding of structural ceramics, SiC, Al₂O₃ and AlN. Grinding process of the ceramics is carried out with varying mesh type, depth of cut and feed rate using diamond wheel. The machining result of the surface roughness and condition of ground surface, have been analyzed by use of surface roughness tester, SEM and three dimensional surface profiler measurement system.
이동희(Donghee Lee),남우철(Woo-chul Nam) 대한기계학회 2021 대한기계학회 춘추학술대회 Vol.2021 No.11
Electromyography (EMG) is the measuring of electrical signal from the skeletal muscles caused by nerve stimulation. Among them, surface electromyography (sEMG) is a non-invasive method of detecting EMG, and it is applied to various fields. Due to its simple acquisition technique, sEMG is widely used as a means of human-computer interaction. For example, the computer could recognize the user’s muscle activation via sEMG and can perform tasks corresponding to the user’s purpose. Usually, classification is required to acknowledge the user’s purpose. However, one of the main obstacles of sEMG is data insufficiency: repetitive experiments can cause muscle fatigue to the user and thereby make it difficult to acquire large amount of data. Accordingly, the classification accuracy can be reduced due to this lack of data. This work proposes a method to augment sEMG signals from a small amount of data by utilizing random field technique. The augmentation of sEMG will enable us to overcome the fundamental obstacle of sEMG on the volume of data.
Covariance matrix decomposition 방법을 통한 인공 뇌파 신호 생성
이회림(Hoi-Rim Lee),남우철(Woo-Chul Nam) 대한기계학회 2021 대한기계학회 춘추학술대회 Vol.2021 No.11
The BMI (Brain-Machine Interface) is difficult to obtain a lot of high-quality datasets due to the characteristics of bio-signals. To address this issue, many previous studies dealing with data augmentation have been conducted. There have been studies using Covariance matrix decomposition (CMD) method to augment brainwave signals. In previous paper, artificial data were generated by multiplying decomposed covariance matrix with random variables that follow standard normal distribution. In this paper, to provide flexibility to CMD, generalized normal distribution (GND) is used instead to augment data. Classification performance using data generated using GND was increased by up to 7.32% and 8.32% in versions 1 and 2, respectively.
유다영(Dayoung You),남우철(Woo-chul Nam) 대한기계학회 2021 대한기계학회 춘추학술대회 Vol.2021 No.11
Brain-Computer Interface (BCI) enables users to communicate and control systems with brainwave signal. P300 is a signal of the event-related potential generated during an oddball paradigm. Recent studies have focused on P300-based BCI because it is relatively easy to be used as control signal. Moreover, no user training before experiment is required. In this study, P300 brainwave was acquired from one subject. Then, the effects of the epoch number on the classification performance (i.e., F1-score) were investigated. The result suggests that high accuracy can be obtained even with a small number of epochs. To verify this model, a real-time experiment was also conducted with the trained models.
곽태수(Tae-Soo Kwak),남우철(Woo-Chul Nam),김유영(Yoo-Young Kim),김경년(Kyung-Nyun Kim),이용철(Yong-chul Lee) 한국기계가공학회 2009 한국기계가공학회 춘추계학술대회 논문집 Vol.2009 No.6월
This study has been focused on properties of mirror surface grinding technology by ELID(ELectrolytic In-process Dressing) for structural ceramics using in high precision structural parts on semi conductor manufacturing processes. ELID grinding is an excellent technique for mirror grinding of various advanced metallic or nonmetallic materials as hard to machining materials. The experimental studies have been carried out to get mirror surface for grinding of structural ceramics, SiC, Al₂O₃ and AlN. Grinding process of the ceramics is carried out with varying mesh type, depth of cut and feed rate using diamond wheel. The machining result of the surface roughness and condition of ground surface, have been analyzed by use of surface roughness tester, SEM and three dimensional surface profiler measurement system.