• 한국연소학회:학술대회논문집
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• 한국연소학회 2000년도 제21회 KOSCO SYMPOSIUM 논문집
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• pp.17-23
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• 2000

Knock in SI engines causes physical damage to the piston and combustion chamber and lowers the thermal efficiency. The increase in compression ratio which can improve the thermal efficiency and engine performance has been limited by engine knock. So the need of making clear the knocking phenomenon has increased. This paper reviews the methods of knock detection, characterization and prediction of knock with the reduced chemical kinetic modeling.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2007년도 춘계학술대회 논문집
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• pp.74-78
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• 2007

This study purports to survey on the illumination environment design in gallery. These gallery spaces need to improve individual illumination environments, in compliance with the recommended ratio of illumination intensity to brightness, and to create a new illumination design using a wide variety of illuminations.

• 한국식품영양학회지
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• 제9권2호
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• pp.116-122
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• 1996

This study aimed at the effect of carbohydrate level on serum glucose and lipid in Korean female 300 NIDDM patients. Mostly NIDDM appears in 50-64 years. As carbohydrate level increased, nutrient intakes increased. Most carbohydrate intakes were polysaccharides. High carbohydrate diets made blood glucose level increased. But high carbohydrate-fiber diets result lowering effect on serum LDL /HDL-cholesterol ratio and triacylglycerides. In conclusion, NIDDM patients need regular exercise and total energy intake balance. High carbohydrate-fiber diets are recommendable.

• 한국연소학회지
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• 제5권2호
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• pp.29-35
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• 2000

Knock in SI engines causes physical damage to the piston and combustion chamber and lowers the thermal efficiency. The increase in compression ratio which can improve the thermal efficiency and engine performance has been limited by engine knock. So the need of making clear the knocking phenomenon has increased. This paper reviews the methods of knock detection, characterization and prediction of knock with the reduced chemical kinetic modeling.

• 교육시설
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• 제6권4호
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• pp.5-15
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• 1999

This study aims to suggest guidelines of open classroom in open elementary school. It consists of following three parts. The first part takes a theoretical review of open education and open classroom. And the second makes analysis of architectural characteristics of open classroom as case studies which are analyzed in terms of modul, function and ratio of open space, etc. The last part is user need analysis of the open space.

• 한국광학회:학술대회논문집
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• 한국광학회 2000년도 하계학술발표회
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• pp.126-127
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• 2000

In this paper, we proposed an optical encryption method based in the concept of visual cryptography and interferometry. In our method a secret binary image was divided into two sub-images and they were encrypted by 'XOR' operation with a random key mask. Finally each encrypted image was changed into phase mask. By interference of these two phase masks the original image was obtained. Compared with general visual encryption method, this optical method had good signal-to-noise ratio due to no need to generate sub-pixels like visual encryption.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2003년도 춘계 학술발표회논문집
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• pp.259-266
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• 2003

This paper begins with the seismic performance evaluation of an existing building, which exhibits the need of additional damping to reduce its response. Required damping ratio is found by capacity spectrum method to satisfy a target response. It is expressed with the design parameter of active mass damper by adopting Linear Quadratic Regulator, Optimal gains are obtained and then weighting matrices are found. Finally the seismic performance by added active mass damper is demonstrated, which satisfies the target response.

• 한국위성정보통신학회논문지
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• 제9권3호
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• pp.5-8
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• 2014

최근 스마트 디바이스는 다양한 프로그램의 사용이 가능하고 무선 데이터 통신과 개인 서비스를 통해 소셜네트워크 서비스가 가능하다. 이러한 특성으로 인해 우리나라 교육 시설에서는 이미 많은 인프라를 구축하여 스마트 디바이스를 이용한 강의를 제공하고 있다. 그러나 작은 디스플레이는 학습자의 강의 시청에 불편함이 발생하여 학습능률을 저하시킬 수 있다. 이러한 학습저하를 극복하려면 작은 디스플레이에서 효과적인 학습을 할 수 있는 컨텐츠 레이어 포맷이 필요하다. 본 논문에서는 황금비율 기반의 스마트 디바이스용 컨텐츠 레이어 포맷을 벡터방식인 일러스트 프로그램으로 개발하여 제안한다.

• 소성∙가공
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• 제4권2호
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• pp.151-158
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• 1995

In this study, the width spreads of spring steel including Mn-Cr steel(SUP 9A), Mn-Cr-V steel(SUP 11A), and Si-Cr steel(SAE 9254) and were investigated under different reduction ratios and thickness-width ratios friction coefficients. The experimental results were compared with the theoretical prediction by the Ekelund equation, Geuze equations, etc. The width spreads of the three spring steels were found to be 10-15% larger than mild steel, and the optimal reduction ratio for the spring steel was found in a range from 20 to30%. Among the spring steels, the width spread of Mn-Cr-V steel was measured to be the largest followed by those of Si-Cr steel and Mn-Cr steel. It was found that the width spread increased with friction coefficient, width-thickness ratio and reduction ratio as predicted. However, the theoretical predictions revealed smaller width spread than the experimental results. This finding indicates that the coefficients of the width spread of the theoretical models need to be modified in order to predict the actual behavior of the width spreading of the spring steels. In this study, the coefficients of width spread of the Geuze equation were determined from the experimental results.

• 한국항행학회논문지
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• 제17권2호
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• pp.202-207
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• 2013

본 논문에서는 병렬 연결된 전송선로를 이용하여 고 비율 비대칭 전력 분배기를 설계하였다. 병렬 연결된 전송선로는 마이크로스트립 기술로 구현하기 어려운 낮은 임피던스의 전송선로를 높은 임피던스 전송선로로 구현하는 방법이다. 비율 비대칭 분배기 구현 시 사용되는 낮은 임피던스를 구현하기 위하여 병렬 연결된 전송선로를 이용함으로서 구현을 쉽게 할 수 있었다. 이러한 설계방법의 타당성을 보이기 위해서 중심 주파수 1 GHz에서 10:1 비율의 비대칭 전력 분배기를 제작하였고, 이것의 특성은 시뮬레이션과 거의 동일함을 확인하였다.