http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
정진은,전세훈 한국산학기술학회 2019 한국산학기술학회논문지 Vol.20 No.12
Turbochargers are an effective device to reduce the fuel consumption. In this study, the mass flow rate of pulsating flow in the twin-scroll turbocharger for the gasoline engine of passenger vehicles was measured. Pulsating flow was achieved using a pulse generator and the mass flow rate of the unsteady pulsating flow was analyzed by comparing it with those of the steady flow. The pulse generator consisted of a rotating upper plate and a fixed lower plate. To measure the mass flow rate of unsteady flow, the orifice flow meter equipped with the difference pressure transducer was used. To analyze the low speed performance of the turbocharger, the measurement was carried out in the speed of turbocharger from 60,000rpm to 100,000rpm. The mass flow parameters of the unsteady pulsating flow showed a large difference compared to those of the steady flow. Those of the unsteady flow showed the hysteresis loop surrounding the mass flow parameters of the steady flow and the maximum variation of the mass flow parameters were 5.0 times those of the steady flow. This phenomenon is the result of the filling and emptying the turbine volute space due to pulsating flow. 터보과급기는 엔진에 장착하여 연비를 개선하는 효과적인 장치로 디젤엔진과 가솔린엔진 모두에서 광범위하게 사용되고 있다. 본 연구에서는 승용차용 가솔린엔진에 사용되는 트윈스크롤 터보과급기에서 발생하는 맥동유동의 질량유량을 측정하였다. 자체 설계 제작한 맥동유동장치를 사용하여 맥동이 있는 비정상상태에서 유동의 질량유량을 측정하였고, 맥동이 없는 정상상태의 질량유량과 비교 분석하였다. 맥동유동장치는 회전하는 상판과 고정된 하판을 사용하여 변하는 엔진의 배기밸브 유효면적을 반영하였다. 맥동이 있는 비정상상태 질량유량을 측정하기 위하여 차압식 압력계를 이용한 오리피스 유량계를 사용하였다. 이때 기체의 온도와 절대압력을 측정하여 기체 밀도 변화를 고려하였다. 터보과급기의 저속 성능을 분석하기 위하여 압축공기를 사용하여 터보과급기 회전속도 60,000rpm에서 100,000rpm의 범위에서 측정을 수행하였다. 비정상상태의 질량유량은 정상상태와 비교하여 크게 다른 결과를 보였다. 정상상태 질량유량 계수는 터빈 팽창비가 증가함에서 따라 증가하지만, 비정상상태 질량유량 계수는 정상상태 값 주변의 히스테리시스 루프를 형성하며 변화량은 정상유동 기준 최대 5.0배이다. 이것은 맥동유동에 의하여 터빈 볼류트 공간에서 충진과 방출이 일어나기 때문이다.
정진은,장성태 한국기술교육대학교 2003 論文集 Vol.10 No.1
It is proven that most air pollution of the big city results from the emissions of vehicles. Therefore the proper maintenance of the emissions control system of them is important. In this study a portable automotive emission analysis system which can instantaneously and continuously measure the emissions was developed. The system consists of the portable gas analyzer, the computer with A/D board, and the program with LabVIEW and Excel. By using this the concentration of the emissions were measured and analyzed for the warm-up, bad ignition, bad injection, lean mixture and rich mixture. The results show that this system may be used to diagnose the emission control system of the vehicles in the repair field.
정진은 한국식생활문화학회 1992 韓國食生活文化學會誌 Vol.7 No.3
This study was designed to investigate and quantify components of the connotative meaning of foods, and to analyze the correlations between food concepts and food frequencies on elderly Korean. It involves adapting a communications research tools, the semantic differential and demonstrating its use with two population groups, urban and rural aged. The data were collected by interviewing 217 males and females of 70 years of age and older living in urban and rural areas. To assess how they feel and what they know about foods, the instrument which contains concepts of price, taste, goodness of health, interest, usuality, likes and dislikes, appetite, fattening, quality, and nutritive value about foods were developed. The result shows that there are significant correlations between food concepts and food frequencies. The more affirmative concepts the elderly have, the more food frequencies tend to be. positive concepts are appeared on the meat, fishes, vegetables & fruits, Kimchi and the rice, but negative connotations are appeared on the milk and sugar. There are significant differences between the urban and rural elderly on food concepts.