http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
단상 계통연계형 태양광 인버터의 출력 전류 직류분 저감을 위한 저비용 션트 전류 측정법
류형민(Hyung-Min Ryu) 한국조명·전기설비학회 2016 조명·전기설비학회논문지 Vol.30 No.5
An unwanted DC component in output current of single-phase grid-connected photovoltaic inverters is strictly limited by regulations. The output DC current component is mainly due to the fact that the offset in a current sensor used to measure the output current drifts with temperature. To solve such a thermal drift problem, several solutions compensating the offset error by detecting the output DC current component, and a shunt-based current sensing technique measuring the voltage of a shunt resistor inserted in the inverter output by isolation have been proposed. In this paper, in order to solve the isolation issue causing almost all of the cost in the conventional shunt-based current sensing technique, a non-isolated shunt-based current sensing technique by changing the position of the shunt resistor is proposed. The validity of the proposed method is verified by experimental results of a 3㎾ prototype.
영구 자석형 동기 전동기를 이용한 고속 엘리베이터 구동 시스템 개발
류형민(Hyung-Min Ryu),김성준(Sung-Jun Kim),설승기(Seung-Ki Sul),권태석(Tae-Seok Kwon),김기수(Ki~Su Kim),심영석(Young-Seok Shim),석기룡(Ki-Riong Seok) 전력전자학회 2001 전력전자학술대회 논문집 Vol.2001 No.7
In this paper, the gearless traction machine drive system using a permanent-maget motor for high-speed elevators is addressed. This application of permanent-magnet motor to the elevator traction machine enables several improvements including higher efficiency, better ride comfort, smaller size and weight, and so on. PWM boost converter is also adopted so that DC-link voltage regulation, bi-directional power flow, and controllable power factor with reduced input current harmonics are possible. To increase reliability and performance, the control board, which can include the car and group controller as well as PWM converter and inverter controller, is designed based on TMS320VC33 DSP. The simulator system for high-speed elevators has been developed so that the drive system of high-speed elevator can be tested without any limitation on ride distance and the load condition. Some experimental results are given to verify the effectiveness of the developed system.
복숭아 씨앗 분말을 첨가한 청포묵의 항산화 기능 맟 품질 특성
류형민 ( Hyung Min Ryu ),전대광 ( Dae Kwang Jeon ),김상아 ( Sang A Kim ),정현정 ( Hyun Jung Chung ) 한국식품저장유통학회(구 한국농산물저장유통학회) 2013 한국식품저장유통학회지 Vol.20 No.3
본 연구는 폴리페놀이 다량 함유되어 있는 복숭아씨를 분말상태로 우리 나라의 전통 식품인 청포묵에 적용하여 품질특성 및 항상화성에 미치는 영향을 알아보았다. 복숭아씨 분말의 비율을 각각 0, 0.5, 1.0, 1.5%로 하여 제조한 청포묵은 비율이 높아질수록 명도(L)와 적색도(a)는 낮아지는 경향을 보였으나, 황색도(b)는 1.5%에서 가장 높은 값인 -58.96을 나타내었다. 청포묵의 기계적 품질 특성은 대조군이 모든 특성면에서 가장 높았고, 복숭아씨 분말이 첨가될수록 경도, 응집성, 탄력성, 씹힘성, 부서짐성이 모두 유의적으로 낮아지는 경향을 보였다. 총 폴리페놀 함량의 경우는 복숭아씨 분말을 첨가한 청포묵이 대주군에 비해 높았으며 복숭아씨 분말을 1.5% 첨가하였을때 가장 높은 값을 나타내었다. 또한 복숭아씨 분말 첨가량이 높은 청포묵이 높은 DPPH라디칼소거능을 나타내었다. 관능적 품질 특성은, 다른 관능적 특성은 비슷한 경향을 보였으나 향과 맛에 있어서는 차이점을 보였다. 특히 0.5%를 첨가한 청포묵에서 향 6.0점, 맛 5.5점으로 가장 높은 기호도를 보였고, 첨가량이 증가하게 되면 오히려 기호도가 줄어드는 경향을 보였다. 이러한 결과를 종합해 보면, 기호도 측면에서 대고죽와의 차이가 크지 않은 0.5%를 첨가하는 것이 청포묵의 항산화성도 증진시키고 기계적 및 관능적 품질 특성에도 기여할 것으로 사료된다. The objective of this study was to evaluate the quality characteristics of mungbean starch gels that were prepared with different concentrations (0, 0.5, 1.0 and 1.5%) of peach seed powders (PSP), which exhibit antioxidant characteristics. Mungbean starch gel samples were prepared and subjected to quality characteristics such as moisture content, general components, color, texture profile analysis, total polyphenol contents, DPPH radical scavenging activity, and sensory qualities. The L-value and the a-value for color decreased significantly, whereas the b-value increased significantly as the PSP concentration increased (p<0.05). In the texture profile analysis, the mungbean starch gel with 1.5% PSP showed significantly lower degrees of hardness, cohesiveness, springiness, gumminess and brittleness (p<0.05). The total polyphenol content was highest in the 1.5% PSP to which mungbean starch gel was added, which also showed a higher than 70% DPPH radical scavenging activity level in a dose-dependent manner (p<0.05). In the sensory test of the mungbean starch gel, its sensory scores for flavor and taste were highest in the 0.5% PSP to which mungbean starch gel was added.
최적화 설계를 통한 혼합가스 성능시험용 고온 고압 용기의 제작
구현곤(Hyoun-Kon Ku),류형민(Hyung-Min Ryu),안재웅(Jae-Woong Ahn),배영관(Young-Gwan Bae),김진희(Jin-Hee Kim) 한국기계가공학회 2019 한국기계가공학회지 Vol.18 No.11
In this study, the high-temperature high-pressure vessel was successfully manufactured, which can be used to store pressurized air and to increase the temperature for the mix performance test of high-temperature high-pressure air with coolant (e.g., water). In this research, static structure analysis and transient thermal analysis were performed using the commercial software Midas NFX 2015 R1. Based on the results, the optimized pressure vessel design was carried out. As a result of the optimized design, the minimum stress and minimum weight were found at 120 ㎜ of the vessel thickness, and the optimized pressure vessel was verified. Finally, through manufacture and performance test (e.g., the non-destructive inspection and hydraulic pressure test), the reliability and safety were validated for the designed pressure vessel.