• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 2009년도 추계학술대회
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• pp.223-226
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• 2009

본 논문에서는 플래시 영상을 기반으로 하면서 비-플래시 영상의 색상 정보를 이용하여 디지털 카메라의 사진 영상을 합성하는 알고리즘을 개선하였다. 장호석 등이 제안한 기존의 적응적 색상전달 알고리즘은 대부분의 경우에 만족스러운 결과를 나타냈지만, 두 영상 사이에 변이가 존재하는 경우에 적용하기 곤란한 한계와 함께 플래시로 인한 조도의 차이가 심한 경우에 배경 영역에서 문제점을 가지고 있다. 따라서 본 논문에서는 이러한 문제점을 개선하기 위해 플래시 및 비-플래시 영상 정렬과 배경 영역 개선 기법을 적용하였다. 이로서 제안된 알고리즘은 기존 알고리즘 보다 현실적이고 자연스러운 영상을 보여준다.

• 한국연소학회지
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• 제7권3호
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• pp.37-46
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• 2002

Characteristics of lifted flames in axisymmetric laminar coflow jets have been investigated experimentally. Approximate solutions for velocity and concentration accounting virtual origins have been proposed for coflow jets to analyze the behavior of liftoff height. From the measurement of Rayleigh intensity for probing the concentration field of propane, the validity of the approximate solutions was substantiated. From the images of OH PLIF and CH chemiluminescence and the Rayleigh concentration measurement, it has been shown that the positions of maximum luminosity in direct photography coincide with the tribrachial points, which were located along the stoichiometric contour. The liftoff height in coflow jets was found to increase highly nonlinearly with jet velocity and was sensitive to coflow velocity.

• 한국자동차공학회논문집
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• 제12권3호
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• pp.10-18
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• 2004

It is well known that the stratified charge combustion has many kind of advantages to combustion characteristics, such as higher thermal efficiency and less CO, NOx levels than conventional homogeneous mixture combustion. Although this combustion can be caused low fuel consumption, it is produced the high unburned hydrocarbon and soot levels because of different equivalence ratio in the combustion chamber. Moreover it has a lot of possibility of low output and misfire if the mixture gas would not be in existence around the spark plug. In this paper, fundamental studies for stratified combustion were carried out using a constant volume combustion chamber. The effect of locally mixture gas distribution according to control the direct injection and premixed injection in the chamber were examined experimentally. In addition, the effects of turbulence on stratified charge combustion process were observed by schlieren photography.

• 한국자동차공학회논문집
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• 제15권5호
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• pp.153-159
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• 2007

The performance of a direct-injection type diesel engine often depends on the strength of air flow in the cylinder, shape of combustion chamber, the number of nozzle holes, etc. This is of course because the process of combustion in the cylinder was affected by the mixture formation process. In the present paper, high speed photography was employed to investigate the effectiveness of holes penetrated from the bottom of cavity wall to piston crown for some more useful utilization of air. The holes would function to improve mixing of fuel and air by the increase of air flow in the cylinder. The results obtained are summarized as follows, (1) Activated first of the combustion by shorten of ignition timing and rapid flame propagation (2) Raised the combustion peak pressure, more close to TDC the formation timing of peak pressure.

• 한국산업융합학회 논문집
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• 제11권1호
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• pp.5-10
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• 2008

A flame speed of methane mixture of water vapor and air have been measured to study the process of flame propagation using schlieren photographs. The quantity of water vapor contained were changed 5% and 10% of total mixture, and equivalence ratio of mixture between 0.8 and 1.2 were tested under the ambient temperature 323K and 373K. The results showed that the burning velocity was decreased by increasing the water vapor contents due to the interruption of flame development. And, the reduction rate of burning velocity was smaller by increasing the water contents under the same ambient temperature. The effects of ambient temperature on burning velocity was decreased by increasing the water vapor contents.

• 대한한의학회지
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• 제27권2호
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• pp.57-69
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• 2006

For decades, scientists and clinicians have examined methods of measuring scalp hair growth. There has been a greater need for reliable, economical and minimally invasive means of measuring hair growth and, specifically, response to Oriental medicine therapy. We review the various methods of measurement described to date, their limitations and value to the clinician. In our opinion, the potential of computer-assisted technology in this field is yet to be maximized and the currently available tools are less than ideal. The most valuable means of measurement at the present time are global photography and phototrichogram-based techniques (with digital image analysis). Subjective scoring systems are also of value in the overall assessment of response to therapy and these are under-utilized and merit further refinement.

• 한국인쇄학회지
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• 제2권1호
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• pp.23-33
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• 1984

천연색 사진에서 전사과정중 발색화합물을 Polaroid 사 제품과 Kodak사 제품을 선정하여 고찰하였다. 이들 화합물은 초기에 Alkali 가동이거나 불가동이었다. Alkali 가동 화합물은 분해에 의하여 상적으로는 불가동화가 요구되며 Alkali0불가동 화합물은 상적으로 가동화가 요구된다. 고찰겨과 Polaroid사 제품은 Alkali 가동을 나타내며 Kodak제품은 Alkali불가동을 나타냇다.

• 한국인쇄학회지
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• 제13권1호
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• pp.25-37
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• 1995

Today, regarded as a science in photography, the role of the lens and sensitizer is important. In this research, we manufactured simple test lens with a various diaphragm which is based on the general purpose lens, and measured the quantity of light and flare. The objective of this study is to figure out the characteristics of our test lens and maximize its usefulness. The results showed that (1) The quantity of light through the lens was not constant. (2) As for flare, its value was consist. (3) Our lens had the characteristics of the soft lens and (4) It had much chromatic abberation. Therefore, We found that a hand-made lens is to acquire visual image such as the effects of a specialized lens.

• 한국인쇄학회지
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• 제14권1호
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• pp.55-74
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• 1996

In the today, regarded as a science on photography, the role of the lens and sensitized is important. In this research, we manufactured a hand-made lens which is based on the general purpose lens, and made a diapgragm. We measured the quantity of light and resolving power, and take pictures with it. The purpose of this research is to figure out the characteristics of our hand-made lens and maximize its usefulness. The result showed that (1) quantity of light and resolving power through hand-made lens are distributed constant. (2)Our lens had the characteristics of a soft lens and (3)it had much chromatic abberation. Therefore, we found that the hand-made lens is th acquire visual image such as the effects of a specialized lens.

• 한국농촌건축학회논문집
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• 제14권1호
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• pp.91-98
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• 2012

This study is aimed to survey on the perception of residents about general contents and current status of urban traditional houses in Cheongju. A study on methods is using questionnaire which 12 items of attraction in Urban Traditional Houses and experimental study focusing on residents in Seowoon-dong and Seokgyo-dong where traditional houses are concentrated. As a result, residents of urban traditional houses were categorized 6 sectors, which 4 sectors of Seowoon dong and 2 setors of Seokgyo-dong, caused by the road construction. The urban spatial structures of these sectors are maintained, comparing with aerial photography on 1960's. And residents recognize eco-friendly attraction higher than awareness on traditionality, locality and aesthetic beauty. It is proposed to prepare political alternative about traditionality, locality and aesthetic beauty. Low awareness about traditionality and locality have influenced that residents hope the change of the traditional houses.