라면 유지의 안정성에 대한 당과 아미노산의 영향

차경식,이강표,최형택,양 융,오두환 연세대학교 산업기술연구소 1989 논문집 Vol.21 No.1

The effects of various sugars and amino acids of the stability of the plam oil in Ramyon, was studied. Stability of the palm oil in Ramyon was determined from acid, peroxide, anisidine values and color development. The effects of sugars added on the stability of the palm oil in Ramyon was in order of arabinose, xylose, glucose, fructose, lactose, sucrose, raffinose. In addition of amino acids and glucose, the stability of the palm oil in Ramyon showed a significant increase in order of β-alanine, glycine, valine, lysine, but threonine and glutamic acid showed less stability. The effects of glycine concentration on the stability was increased to 0.5%. After deep-fried, color developments of Ramy on surface increased in darkness to 0.5% glycine concentration and decreased during the storage period.

가변 인덱스 방식을 이용한 디지털 잔향기

차경환 東西大學校 2001 동서논문집 Vol.7 No.-

In this paper, we implemented a realtime digital reverberator using feedback type IIR filter and variable index method. This reverberator can reduce the amount of calculation by directly convolution. Also the variable index method can minimize the memory of the reverberant system. So it can represent a various reverberation effect by using recorded room impulse response. The result of reverberator implementation using TMS320C32 DSP Board, we could felt a sense of distance and a space perception in a virtual room.

지각 부호화에서 음향심리모델의 SMR값에 의한 비트 할당 속도 향상

차경환 東西大學校 1996 동서논문집 Vol.2 No.1

Recently developed perceptual coding techniques will play an important role in the future of broadcasting and telecommunications. This paper presents an new method for improvement of the bit allocation time in perceptual coding. The performance of the proposed method is compared to that of the conventional MPEG audio method in terms of bit allocation processing clocks in the TMS320C40 simulator. The results showed that, in case of using zurasic movie sound, the reduction rates were 45.5% and, in case of using violine sound, the reduction rates were 29.3%.

SISO방식을 이용한 폐쇄공간의 능동소음제어

차경환 東西大學校 2001 동서논문집 Vol.7 No.-

In this paper, we implemented the real-time active noise control of system using SISO method. This algorithm could settle the howling problem, which the MIMO system has in general. The SISO system which one microphone can not only input the signal but also observe the error signal was implemented with TMS320C32 DSP Board. Experimental results demonstrate that the noise level was reduced about 80% when the noise level was measured inside closed box after noise source radiated to the closed box.

베르가못(Bergamot) 에센셜오일을 이용한 향기 흡입법이 중년 여성의 스트레스 증상에 미치는 효과

차성환,박경숙 중앙대학교 간호과학연구소 2001 중앙간호논문집 Vol.5 No.2

The purpose of this study was to investigate the effects of Aromatherapy, inhalation method using Bergamot essential oil on stress in middle-aged woman. The study design was a one-group pretest-posttest design. The subject were The inhalation method of Bergamot essential oil was to drop 3 drops of oil on tissue at 09,13,19, before bed for week. The scale used in the study was the stress scale of Park, Sun Young (1999). 45 middle-aged woman with stress. The study was carried out from August 5, to October 5, 2001. The study data was analyzed by percentage, mean, standard deviation and Wilcoxon signed ranks test using SPSS/PC+WIN 10.0 program. The result were as follows; 1. The Score of physical stress scale was significantly decreased after use of inhalation of Bergarmot essential oil. 2.The Score of psychological stress scale was significantly decreased after use of inhalation of Bergarmot essential oil. In Conclusion, the results of this study suggests that inhalation method using Bergarmot essential oil is positively supported in stress reduction in middle-aged women.

AMDF를 이용한 화자위치 추정에 관한 연구

차경환,박수홍,송도훈,이채봉 東西大學校 1999 동서논문집 Vol.5 No.-

본 연구에서는 원격 화상회의 시스템 등에서 Camera를 자동적으로 제어하기 위해 화자의 음성신호를 4개의 마이크폰 배열(Microphone Array)로 수음하여 그 신호에 의해 화자의 위치를 추정한다. 마이크로폰으로 수음한 음성신호의 TDE(Time Delay Estimation)를 계산할때 그 연산량을 감소시키기 위해 AMDF알고리즘을 사용한다. 각 마이크로폰 출력신호에 대해 amdf 알고리즘으로 시가니연을 구하고 DOA(Direction of Arrival)를 계산한다. 다양한 조건하에서 음성신호로 실험한 결과, AMDF 알고리즘을 이용한 화자위치 추정의 정확도가 기존의 cross-correlation 방법에 비해서 우수한 성능을 나타내었다. This paper decribes the estimation of speech source using four microphones array singnal for the automatic control caramera position in the teleconference system. To reduce the calculation rate, AMDF algorithm is empoloyed for the TDE(Time delay Estimation) of the speech signal with microphone. The time delay is calculated using AMDF algorithm of each microphone output signal and DOA is obatained. According to the estimation of speech source in speech signal/아/under various conditions. AMDF-technique-based method yields superier performance to the one with cross-correlation method.

다이아몬드상 카본 박막의 레이저공정 변수에 따른 상변이와 내마모성 특성변화

심경석,차금환,이상렬,김대은 연세대학교 산업기술연구소 1999 논문집 Vol.31 No.2

Diamond-like carbon(DLC) thin films have been fabricated by pulsed laser deposition method with various deposition parameters. The characterization of fabricated thin films was performed depending on the deposition parameters. As the kinetic energy provided by deposition temperature and the laser energy density were increased, the film showed graphite properties. Structural properties of the films were investigated by Raman spectroscopy. The growth energy should be optimized to fabricate high quality DLC thin films. DLC films showed high hardness and their friction coefficients were measured to be about 0.2 regardless of the load of the ball pin.

혈액정상치에 대한 고찰

정경환,차덕원,박재윤 順天鄕大學校 1977 의대논문집 Vol.2 No.-

We have determined the mormal ranges using the probability graph method to the laboratory data. From within ranges there were found that hematolgical normal values and ranges calculated from it were applied to the determination of those, except red blood cells

닥터소음의 피드포워드제어에 관한 연구

김천덕,차경환 釜山水産大學校 1989 釜山水産大學 硏究報告 Vol.29 No.1-2

This paper has described the efficiency for the new method of the active control of the duct noise which is adaptive filtering application by experiment which set the additional sound source. Firstly the active noise control system becomes stable since the acoustic feed back quantity can be set under -30 dB by setting the additional sound source at an excite of duct and for the signal which is supplied to additional sound source by the setting the microphone at the upstream of duct. Secondly, since the noise of duct output and additional sound source constructs dipole source, radiating power will be decreasing over all the direction in comparison with the case without the additional sound source in the range of frequency which the distance between the duct and the additional sound source is shorter than wave length that is a center frequency of the duct noise. The result of noise cancelling amount for simulation and fan noise experiment by the active control system has been attenuated about 5∼6 dB by only using the proposed active control system and about 9∼10 dB can be attenuated by using adaptive filtering algorithm with the proposed active control system on the desired frequency band.

중등도 심부전증 환자에서 Carvedilol의 치료 효과

차동훈,차영수,국진환,황경화,김형태,임상욱,김태용,조윤경,박필원 대한순환기학회 1998 Korean Circulation Journal Vol.28 No.4