http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
회전익 항공기 기어박스 상태감시진단을 위한 음향신호 잡음제거 방법에 관한 연구
안병현(Byung Hyun Ahn),김효중(HyoJung Kim),박선휘(Sunwhi Park),김용석(YongSeok Kim),최병근(ByeongKeun Choi) 한국소음진동공학회 2015 한국소음진동공학회 학술대회논문집 Vol.2015 No.4
Gearboxes are very important for many industrial applications such as wind turbine, power generators and rotorcraft gearboxes. Most of all, this research is focused on rotorcraft gearboxes and condition monitoring & diagnosis system. the purpose of health and usage monitoring(HUM) is to improve flight safety, rotorcraft availability, maintainability, the ability to complete a transmission, and to reduce life cycle costs. Acoustic Emission technique is widely applied to develop the early fault detection system for predictive maintenance, and the problem is about a signal processing method for AE signal mainly focused on. but AE frequency is usually in the range of 150-300 kHz which means it has huge modulated data in signal. it has a advantage of early fault detection but also predictive maintenance while a variety of irrelevant data reduces the performance of condition indicators. that is typically noise from the rotorcraft transmissions and bearings. In this paper, Advanced research is performed by noise reduction techniques in time domain and frequency domain by using AE signal from the motor gearbox. In order to study on rotorcraft gearboxes for condition monitoring and diagnosis.
정한얼(HanEol Joeng),김효중(HyoJung Kim),구동식(DongSik Gu),김학은(Hak Eun Kim),최병근(ByeongKeun Chio) 대한기계학회 2006 대한기계학회 춘추학술대회 Vol.2006 No.6
Recently, demands for the reduction of noise generated by transformers have been increasing. Accordingly the noise of transformer occasion displeasing to residents therefore the transformer needs to decrease of noise. One method of reduction such a noise is to build a free-standing enclosure of concrete and steel plates around the transformer. however, this method has some disadvantages, for example, a lage area is needed for equipment installation. In the paper, the vibration and noise effect which is transferred from reinforce channel to insulation panel generated by transformer have been identified for the several kinds of insulation panel and damping sheet experimentally.
박동희(Donghee Park),안병현(Byunghyun Ahn),김효중(Hyojung Kim),하정민(Jeongmin Ha),임강민(Gangmin Lim),최병근(Byeongkeun Choi) 한국소음진동공학회 2017 한국소음진동공학회 논문집 Vol.27 No.5
Ultrasound signal is widely used to detect fault by heterodyned signal. Typically an expert will scan around the object with the scanning module while listening through headphones and observing a display panel. But this diagnosis procedure is required by specialized expert and hardly detect early defect. In this paper, Feature selection based on GA (genetic algorithms) is selected from the features of ultrasound signal on frequency domain and time domain. Then, by using the Support Vector Machine one of the machine learning, the performance of classification is evaluated by extracted features and selected features. The results of classification is compared with feature extraction based on PCA (principal component analysis). Therefore, the feature selected for each defect can be used as a reference by feature analysis for ultrasound.