• Journal of Power System Engineering
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• v.4 no.2
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• pp.11-16
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• 2000

Simultaneous quantitative measurements are made of the velocity fields for two-dimensional natural convection in a rectangular enclosure using PIV(Particle Image Velocimetry). The experiments are performed at a Prandtl number of 6.62, an aspect ratio of 1.0, Rayleigh numbers from $1.294{\times}10^6\;to\;3.8841{\times}10^6$, and angles of inclination of $0^{\circ},\;30^{\circ}\;and\;60^{\circ}$ inside a $30mm{\times}30mm{\times}8mm$ cavity made of an acrylic glass 10mm, with two isothermal copper walls kept at a prescribed temperature. The experimental results agreed very well with the numerical results. It was found that the flow consisted of a large double convection cell at angle of inclination of $60^{\circ}$.

• Journal of Korean Ophthalmic Optics Society
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• v.3 no.1
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• pp.201-207
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• 1998

It was theoretically calculated the image position and size using matrix to obtain the reflection pattern for eye's cornea and crystalline, and made system to measure the reflection pattern by three light sources and a reflex camera. Hyperopia and myopia were measured by reflect pattern using single light source at retina, and cornea and curvature of crystalline were measured by the reflection pattern using double light sources.

• Proceedings of the Korean Institute of Interior Design Conference
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• 2006.11a
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• pp.193-196
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• 2006

The meaning of the color which has from modern interior space has played important role, i.e. color itself Is the concept creation tool as well as the unique expression sphere in field of interior space far away from fixed idea relevant to the existing color which was only simple decoration or secondary element in space. Thus, this current work expresses that the color is related with decoration effect as well as basic designed-conceptual work process including the space is formed. Furthermore, through the side-composition with color, It activates the various space aspect perceptually, which created the colorful environment in using lightning, reflection of glass and penetrated nature etc. The keyword on color concept is as like various aspects, third dimension, non-materiality and symbolical meaning. In addition, it provides the color space equipped with functionality and artistry capable to arouse the diverse sensual capacity to space users on default of color image language.

• Journal of Multimedia Information System
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• v.4 no.1
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• pp.27-32
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• 2017

Through the development of the medium, Sigmund Freud's uncanny element in the Cinemagraphic technique of digital image is analyzed, and the research problem presented through the case and literature data is interpreted. Look for an Uncanned element as seen from. Interpret the theories found in art paintings and human philosophical perspectives through examples in the overlapping cinema graphs of photographs and videos that we have looked at unfamiliarity. It interprets the double surreal image of Cinemagraph through unfamiliar gaze and evaluates new horizon with digital photograph.

• Journal of ILASS-Korea
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• v.21 no.2
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• pp.88-94
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• 2016

In this study digital holographic microscopy system for measurements of 3-D velocities of particles in MR fluid is developed. Holograms are recorded using either a CCD camera with a double pulse laser or a high-speed camera with a continuous laser. To process recorded holograms, the correlation coefficient method is used for focal plane determination of particles. To remove noise and improve the quality of holograms and reconstructed images, a Wiener filter is adopted. The two-threshold and image segmentation methods are used for binary image transformation. For particle pairing, the match probability method is adopted. The developed system will be applied to measurements of the characteristics of unsteady 3-D particle velocities in MR fluids through the next stage of this study.

• Journal of ILASS-Korea
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• v.15 no.2
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• pp.53-60
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• 2010

This study presents development of digital particle holographic system and its application to spray field to measure three-dimensional velocities and sizes of spray droplets. A double exposure hologram recording system with synchronization system for time control was established and digital holograms can be recorded in a short time interval. To process recorded holograms, the correlation coefficient method was used for focal plane determination of particles. To remove noises and improve the quality of holograms and reconstructed images, the Wiener filter was adopted. The two-threshold and image segmentation methods were used in binary image transformation. For particle pairing, the match probability method was adopted. The developed system was applied to spray field and three-dimensional velocities and sizes of spray droplets were measured. The measurement results of digital holographic system were compared with those made by laser instruments, PDPA(Phase Doppler Particle Analyzer), which proved the feasibility of in-line digital particle holographic system as a good measurement tool for spray droplets.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1997.10a
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• pp.429-434
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• 1997

영상 평활화(Image Smoothing) 작업은 영상 신호 표본화, 정량화, 통신 이동과 같은 과정을 거치면서 잡음 등의 불필요한 신호가 포함된 디지털 영상의 잡음을 감소키는데 많이 이용되고 있다. 이와 같은 영상 평활화 작업에는 대부분 전역적인 공간 영역 혹은 주파수 영역의 전역적인 필터링 기법이 이용되고 있다. 그러나, 기존의 방법들은 왜곡된 잡음 픽셀들의 정보를 그대로 반영하기 때문에 잡음 제거 결과 복원 영상의 선명도는 크게 저해된다. 본 논문에서는 특히나 양자화 과정을 통해 잡음 정보의 변형이 극대화되어지는 압축 영상을 대상으로 하여 적절한 잡음제거 기법을 제안하고자 한다. 특히, 압축 영상의 잡음 추출은 1차 복호화 후의 공간 도메인에서, 추출된 잡음 제거는 주파수 도메인에서 수행함으로써 2차 복호화 후의 잡음제거 결과 영상은 압축 영상의 잡음 제거에 따른 본질적인 문제를 해결하였으며, 실험 결과 역시 다른 기존의 방법에 비해 우수한 성능을 발휘하였다.

• Journal of the Korea Society of Computer and Information
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• v.23 no.3
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• pp.33-40
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• 2018

In this paper, we propose a method to effectively split the adjacent baggage that is moving on high speed conveyor of airport. The proposed method calculate the Angle Histogram(AH) that inspects background pixels within radius r based on the center point of the adjacent baggage. After that, the adjacent baggage is segmented by finding split angles at the AH. We also improved the split quality of adjoining baggage by repeatedly correcting the center point to correctly split adjacent baggage of asymmetric size. And the calculation time of AH is reduced about 1/3 by using the symmetry property of the circle. Experiments have shown that 93% of all adjacent baggage images are correctly segmented and the proposed method is effective.

• Journal of radiological science and technology
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• v.13 no.2
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• pp.15-20
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• 1990

In clinical fields, single screen-film system will be generalized according to high speed and high image qualify of intensifying screen film system in future. In single screen-film system, for imaging the best image, we must choice good film according to speed and gredient. Double screen-film system will be replaced single screen film system in general radiography. Author has thought that single screen film system will be developed new diagnosis area according to X-Ray films.

• Proceedings of the KSME Conference
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• 2000.04b
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• pp.692-697
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• 2000

In Particle Tracking Velocimetry, the analysis of double-exposed photographic plate can be carried out either by means of Young's fringe analysis or by a digital image processing technique. In this study, we used digital image processing to two images in one frame far analyzing in-cylinder flow fields, and compared PTV with PSV(Particle Streak Velocimetry). Additionally, this technique was verified by two different calibration method. One is interpolation by invert distance, the other is interpolation by area ratio. Finally, the results between two interpolation methods were similar in whole flow fields.