• 대한전자공학회논문지TC
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• 제37권12호
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• pp.15-21
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• 2000

본 연구에서는 유전체슬랩으로 덮혀 있고 단락 종단된 평행평판 도파관의 좁은 슬릿을 통한 유전체슬랩 위의 도체스트립과의 전자기적인 결합을 평행평판 도파관에 TEM파가 입사되는 경우에 대하여 고려하였다. 슬릿의 전계와 도체스트립에 유기된 전류를 미지수로 하는 결합적분방정식을 유도하고 모멘트방법을 이용하여 풀었다. 그 결과로부터 슬릿의 폭이 매우 좁음에도 불구하고 도체스트립의 폭과 위치를 적절히 택하면 입사전력의 대부분이 도파관 외부로 결합될 수 있음을 관찰하였다. 또한 도체스트립과 도파관의 윗면이 캐비티를 구성하는 경우와 도체스트립이 기생소자 역할을 하는 경우에 있어서 관찰되는 두 가지 복사현상들 간의 차이점에 대하여 논의하였다.

• 천문학회지
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• 제39권4호
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• pp.151-155
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• 2006

Long slit spectrometers are widely used in optical and infrared bands in astronomy. Absolute flux calibration for extended sources, however, is not straightforward, because a portion of the radiation energy from a flux calibration star is blocked by the narrow slit width. Assuming that the point spread function(PSF) of the star is circularly symmetric, we develop a robust method to extrapolate the detected stellar flux to the unobscured flux using the measured PSF along the slit-length direction. We apply this method to our long slit data and prove that the uncertainty of the absolute flux calibration is less than a few percents.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2005년도 제31회 KOSCO SYMPOSIUM 논문집
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• pp.314-319
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• 2005

In this study, the combustion characteristics were investigated with the variation of design factors on multiple slit gas burner. The design factors consist of slit height, width, spacing, and inner length. The combustion characteristics were made analysis of the CO emission and NOx emission by using CO analyzer and NOx analyzer. The lower perimeter to area and the narrow spacing extends the lift-flame limit. The CO emission increases with the increasing perimeter to area ratio at the same condition. The NOx emission is found to be less significant with the port perimeter to area ratio. The flame interference might highly depend on the spacing and port perimeter to area ratio, and it also affects the burner performance.

• 대한기계학회논문집A
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• 제34권12호
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• pp.1877-1883
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• 2010

선배열 슬릿 마스크를 이용하여 발생시킨 협대역의 레이저 여기 표면파의 주파수 특성을 이론적으로 분석하여 음향비선형성 분석에 영향을 미칠 수 있는 초기 고조파성분의 발생 기구를 규명하였다. 그리고 알루미늄 6061-T6 합금의 음향 비선형성에 대한 슬릿 열림폭과 레이저 세기의 영향을 단일 슬릿과 선배열 슬릿을 이용하여 실험적으로 분석하였다. 고조파 성분의 진폭은 슬릿 열림폭에 의존하는데 본 연구의 경우 슬릿 배열간격을 1.67 mm로 하여 1.75 MHz의 표면파를 발생시켰으며 이 경우 슬릿 열림폭이 0.5 mm에서 1.0 mm로 증가함에 따라 2차 고조파 성분의 진폭은 약 80 % 감소하였다. 또한 레이저 세기에 따라서 기본파 성분 진폭($A_1$)을 변화시키면서 2차 고조파 진폭($A_2$)의 변화를 실험한 결과 $A_1^2$과 $A_2$간에는 우수한 선형 관계를 보였으며, 이는 전형적인 음향비선형성의 특징을 잘 나타낸다.

• Applied Microscopy
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• 제32권3호
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• pp.195-204
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• 2002

TEM 이론의 기초가 되는 델타함수, 콘볼루션 적분, 퓨리에 변환에 관한 개념을 소개하고 이에 대한 응용으로 슬릿함수, 현저한 폭을 갖는 2개의 슬릿, 유한 크기의 파동 train, 좁은 슬릿의 주기적인 배열, 임의의 주기 함수, diffraction grating, 회절 격자, 그리고 gaussian 함수에서의 퓨리에 변환에 관한 수학적인 방법의 적용을 소개하였다.

• 복식문화연구
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• 제8권6호
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• pp.915-929
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• 2000

As a result of research, the character of the general dress-costumes from the late 17th century to the early 18th century in Genre Paintings of DuSeo Yun and YoungSeok Cho is as follows. Firstly young women wore braided hair at the back of head and married women wore hair in the style of Unjeun-mori with Gache. The length of Jeogori (Korean traditional jacket) covered waistor shortened to waist length. The width of Jeongori was suitable, because side-seam line was straight or oblique as it comes into inner line. The width of Git was enough and Mokpan-git (shape of board) and Kal-kit (shape of knife) appeared, and sometimes used other color fabric. Sleeve was narrow and ostly folded up. Chima (Korean traditional skirt) used darker color fabric than Jeogori and the width of Chima was narrow and its length was short. Sokbaji (Korean traditional underpants) shown below were narrow and its end narrower. They were barefoot or they wore Hye (Korean traditional shoes) after putting on Beoseon (Korean traditional socks). Secondly general man's hair tie a topknot (sangtu) and put on headdres, 'Bang-lip', 'Mang-geon', hairband, 'Tang-geon' on head. The length of Jeogori became shorter from the line which covered hip to the line which covered waist. The width of Jeogori was suitable and sometimes it had a slit of side-seam line. The width of Git (neckand) was wide and the length of Git was long. 'Kal-git'appeared and it used other color fabric. The shape of sleeve was straight and narrow. They folded up their sleeves. They folded up their sleeves. They folded up their slack that look like 'Jam-bang-i'and the width of slacks was not suitable, and it was narrow. Baji (Korean traditional pants) were with or without knot, worn 'Hangjeon'(ankle band). They were barefoot and wore 'Hye'or 'Jipsin'(Korean traditional straw shoes). Thirdly a person of high birth or a low-ranked official put 'Yu-geon', 'Mang-geon', 'Gat', 'Tang-geon', 'Bok-du', 'Bok-geon', 'Whi-hang'on their head on a topknot. They wore 'Po (Shim-ui, Jick-ryeong'Jung-chi-mak, Do-po, etc)'on Baji and Jeogori. 'Po'was long and wide, it knot with 'Se-jo-dae'(string belt) or 'Po-baek-dae'(band belt). It had a slit of sideline and 'Mu'which had or had not or which were hard to confirm. The shape of sleeve was straight or very wide and its length was long. The width of Baji was wide and knotted with 'Hangjeon'and wore'Beoseon'and 'Hye'. Fourthly child's hair was short or knotted to the back of the head. The length of Jeogori reached waist line and its width was wide. It had a 'Jeogori'which had s slit of sideline. The shape of sleeve was 'Tong-su'(straight), and the length of sleeve was diverse. They put 'Baeja'on 'Jeogori'. The width of Baji was not wide. They wore them straight without or with knot, 'Hangjeon'. They were barefoot or put on 'Jipsin'.

• 대한금속재료학회지
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• 제49권3호
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• pp.221-230
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• 2011

The cold spray process is an emerging technology that utilizes high velocity metallic particles for surface coating. Metallic powder particles are injected into a converging-diverging de Laval nozzle and accelerated to a high velocity by a supersonic gas flow. The cold spray process normally uses a circular nozzle that has a rather narrow spraying range. To overcome this fault, a slit nozzle was considered in this study. The slit nozzle is anticipated to reduce the coating process time because it has a wider coating width than the circular nozzle. However, the slit nozzle can reduce the coating efficiency because it does not allow as much gas and particle velocity as the circular nozzle. To improve the coating efficiency of a slit nozzle, the shape of the slit nozzle was modified. And the results of gas flow and particle behaviour according to the nozzlers shape were compared by the a numerical analysis. As a results, as Expansion Ratio(ER) of 7.5 was found to be the most optimal condition for enhancing the spraying efficiency when the ER was changed by the variation of nozzle neck and exit size.

• 한국전자파학회논문지
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• 제18권5호
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• pp.569-575
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• 2007

도체 평판의 좁은 단일 슬릿 구조에서 슬릿을 통한 투과 공진 현상을 전자기학적인 관점에서 모멘트 방법으로 해석하고 투과계수에 대한 수치 결과를 기존의 결과와 비교 검토하였다. 특히 투과 폭(transmission width)에 대한 해석적인 근사 표현식이 유도되었다.

• 한국전산유체공학회지
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• 제20권2호
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• pp.46-51
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• 2015

In this paper, we have developed numerical model for particulated flow through narrow slit using Eulerian-Granular method. Commercial software (FLUENT) was utilized as simulation tool and main focus was to identify the effect from various numerical options for modeling of solid particles as continuos phase in granular flow. Gidaspow model was chosen as basic model for solid viscosity and drag model. And lun-et-al model was used as solid pressure and radial distribution model, respectively. Several other model options in FLUENT were tested considering the cross related effect. Mass flow rate of the particulate through the slit was measured to compare. Due to the high volume density of the stacked particulates above the slit, effect from various numerical options were not significant. The numerical results from basic model were also compared with experimental results and showed very good agreement. The effects from the characteristics of particles such as diameter, angle of internal friction, and collision coefficient were also analyzed for future design of velocity resistance layer in solar thermal absorber. Angle of internal friction was found to be the dominat variable for the particle mass flow rate considerably. More defined 3D model along with energy equation for complete solar thermal absorber design is currently underway.

• 천문학회보
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• 제36권2호
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• pp.74.1-74.1
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• 2011

To probe the connection between starburst and AGN activity, we investigate the relation between the 3.3 micron~PAH emission and AGN properties based on the new AKARI observations and the data collected from the literature. Using a sample of low-z Type I AGN, we measure the global 3.3 micron PAH luminosity from the AKARI slit-less spectroscopy. The 3.3 ${\backslash}$micron~PAH emissions are detected for 7 out of 26 target galaxies, but we find no strong correlation between the 3.3 ${\backslash}$micron~PAH emission and AGN luminosity, suggesting that global star formation may not be tightlyrelated with AGN activity. In contrast the to global star formation, the nuclear 3.3 micron~PAH emission luminosity, which are measured from ground-based long slit spectroscopy with a narrow slit, correlates with AGN luminosity. These results imply that starburst and AGN activity are directly connected at the nuclear region.