http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
이기택(K. T. Lee),정영국(Y. G. Jung),임영철(Y. C. Lim) 전력전자학회 2009 전력전자학술대회 논문집 Vol.2009 No.1
For some decades, power quality did not cause any problems, because it had no effect on most of the loads connected to the electric distribution system. With the increased use of sophisticated electronics, high efficiency variable speed drive, and power electronic controller, power quality has become an increasing concern to utilities and customers. Voltages sag and swell are the most common type of power quality disturbance in the distribution system. In this paper, a new family of simple topologies called an Quasi Z-Source dynamic voltage sag/swell restorer is proposed. It is based on a single-phase quasi-Z-Source AC-AC converter which has features such as the input voltage and output voltage are sharing the same ground, and the input current operates in continuous current mode. For the detection of voltage drop, every half of sampling values calculates and compensates the difference voltage. PSIM simulation is presented to verify the proposed concept and theoretical analysis.
이상덕(Sang-Duk Yi),주정현(Jeong-Hyeon Joo),이규희(Gyu-Hee Lee),이기택(K. T. Lee),오만진(Man-Jin Oh) 한국식품영양과학회 2003 한국식품영양과학회지 Vol.32 No.5
밀 단백질에 효소가수분해할 때 생산되는 peptide의 항균활성과 천연항균제로서의 이용가능성을 검토하기 위하여 실험을 행하였다. 밀 단백질에 7종의 단백질가수분해효소를 작용시켜 생성된 가수분해물의 항균활성을 측정하고 한외여과, membrane filtration, HPLC를 이용하여 항균성 peptide를 분리 정제한 후 분자량과 아미노산 결합순서를 측정한 결과는 다음과 같다. 밀 단백질에 7종의 단백질 분해효소를 적용시켜 제조한 가수분해물중 Asp. saito protease를 적용시켜 얻어진 peptide만이 항균활성을 나타내었다. Asp. saito protease는 37℃, pH 6.0에서 작용시킨 경우에 항균활성이 가장 높았으며, 50℃ 이상에서는 활성을 나타내지 않았다. 밀단백 효소가수분해물은 membrane filtration에 의하여 분자량 1,000~3,000에서 항균활성이 나타났다. Membrane filtration으로 얻어진 항균활성분획을 HPLC로 분리한 결과 retention time 31.1~31.8 min에서 항균활성을 나타내었다. 밀단백 효소가수분해물은 121℃에서 15분간 가열하여도 효소활성이 유지되는 매우 안정한 화합물이었다. 항균활성분획을 MALDImass로 질량을 분석한 결과 1,633이었다. 항균성 peptide의 아미노산 결합순서는 cysteine, glycine, prolin, valine, valine, alanine, alanine, arginine의 순서였다. This study was carried out to investigate whether peptide produced from wheat protein by enzyme hydrolysis can be used as a natural antimicrobial agent. Antimicrobial peptide was obtained from wheat protein hydrolyzed by 7 of protease. The produced antimicrobial peptide was purified through ultrafiltration, membrane filtration and HPLC, and molecular weight and amino acid sequence of the purified antimicrobial peptide were determined. Among hydrolysate produced from wheat protein by 7 of protease, antimicrobial activity was observed for the peptide obtained from Asp. saito protease. The Asp. saito protease did produce antimicrobial hydrolysate showing the highest antimicrobial activity at reaction condition of 37℃ and pH 6.0, but not at reaction condition above 50℃. Wheat protein hydrolysate was fractionated by membrane filtration and showed antimicrobial activity between molecular weight 1,000~3,000. The antimicrobial activity fraction obtained by membrane filtration was separated through HPLC and showed antimicrobial activity in the peak of retention time 31.1~31.8 min. We could convince this hydrolysate as heat-stable peptide since antimicrobial activity was maintained after treated with heat for 15 min at 121℃. Molecular weight of antimicrobial peptide identified by MALDI-mass was 1,633. Amino acid sequence of antimicrobial peptide was cysteine, glycine, prolin, prolin, prolin, valine, valine, alanine, alanine and arginine.