• 한국멀티미디어학회논문지
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• 제24권8호
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• pp.1012-1019
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• 2021

Currently, since the black-white QR (Quick Response) codes have limited storage capacity, color QR codes have been actively being studied. By multiplexing 3 colors, the color QR codes can allow the code capacity to be increased by three times, however, the color multiplexing brings about the possibility of crosstalk and noises in the acquisition process of the final image, incurring the decrease of bit-recognition rate. In order to improve the bit recognition rate, while keeping the storage capacity high, this paper proposes a new type of color QR code which uses the pattern information as well as the color information, and then analyzes how to increase the bit recognition rate. For this aim, the paper presents an efficient system which extracts embedded information from color QR code and then, through practical experiments, it is shown that the proposed color QR codes improves the bit recognition rate and are useful for commercial applications, compared to the conventional color codes.

• 한국전기전자재료학회논문지
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• 제30권7호
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• pp.463-468
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• 2017

Eight types of LED packages were manufactured according to the type and composition ratio of phosphors by using commercially available white LED phosphors. CRI (Ra), a conventional color quality evaluation method was evaluated by using manufactured white LED; the Rf, Rg, color vector graphic, and color distortion graphic were evaluated with a new method, IES TM-30-15. The results of the evaluation confirmed that the new method compensated for the disadvantages of CRI, which was found to be inadequate when the color was saturated. The added evaluation index identified the chroma variation and color change. Furthermore, the study showed that the changes of Rf and Rg are small when controlling phosphors based on CRI, questioningthe necessity of identifyingchroma variation and color change.

• 한국유기농업학회지
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• 제22권4호
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• pp.645-656
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• 2014

본 연구에서는 우리 식생활과 가장 밀접한 관계가 있는 고추(청고추, 홍고추)를 유기 및 관행으로 재배하여 품질특성과 기능성성분 함량을 비교 분석하였다. 유기 및 관행재배 고추의 품질특성은 pH, 가용성고형물 함량, 경도 및 색도를 분석하였다. 그 결과 유기 및 관행재배 고추의 가용성고형물이 유기재배에서 2.6~10% 높은 경향을 나타내었으나 경도는 관행재배에서 높게 나타났다. 기능성 성분은 클로로필 함량, ASTA 값, 총페놀성화합물 함량 및 SEM을 통한 세포조직을 검토하여 비교분석 하였다. 청고추의 경우 유기재배에서 관행재배에 비해 녹색도(-a value)값이 더 높게 나타났으며 chlorophyll 함량 또한 a, b, total 값이 전반적으로 높게 나타났다. 홍고추의 경우 유기재배에서 붉은색의 정도를 나타내는 ASTA 값이 28% 더 높게 나타났다. 또한 항산화효과가 있는 것으로 알려진 총페놀성화합물 함량은 청고추와 홍고추에서 모두 유기재배가 관행재배 보다 더 높은 것으로 조사되었다. 따라서 고추 유기재배의 경우 고추 색깔에 관계없이 품질특성 측면에서 색택이 더 우수하고 기능성 측면에서 또한 더 우수한 것으로 사료된다.

• 전자공학회논문지B
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• 제33B권4호
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• pp.101-110
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• 1996

Color image quantization is a process of selecting a set of colors to display an image with some representative colors without noticeable perceived difference. It is very important in many applications to display a true color image in a low cost color monitor or printer. the basic problem is how to display 224 colors with 256 or less colors, called color palette. In this paper, we propose an algorithm to design the 256 or less size color palette by using spatial maskin geffect of HVS and subjective distortion measure weighted by color palette by using spatial masking effect of HVS and subjective distortion measure weighted by color activity in 4*4 local region in any color image. The proposed algorithm consists of octal prequantization and subdivision quantization processing step using the distortion measure and modified Otsu's between class variance maximization method. The experimental results show that the proposed algorithm has higher visual quality and needs less consuming time than conventional algorithms.

• 한국염색가공학회지
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• 제18권5호
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• pp.72-79
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• 2006

There are many discrepancies between visually perceived color-difference and that which is quantified from an instrumental measurement when dark color samples are measured in the textile industry. The samples were prepared to represent these dark shades and the values of the instrumental results from conventional color-difference formulae(CIELAB, CMC, BFD II, CIE94, LCD99 and CIEDE2000). Those of visual assessment were compared. The experimental results show that the CIELAB formula gives the best performance over other formulae, and the CIEDE2000 formula for the color-difference according to chroma presents the worst performance. Therefore, we can say that the problems in color matching of dark shades are caused by imperfect formula, because the results obtained from a color-difference formulae are different and the CMC which is used as a standard color-difference formula in the textile industry is not correct. So, a revised color-difference formula is proposed in this study, to account for these problems.

• 조명전기설비학회논문지
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• 제25권2호
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• pp.43-52
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• 2011

LED lighting may cause different sensation and color appearance due to the different spectral power distributions compared to those of conventional lightings. Particularly, the CCT (Correlated Color Temperature) of LED lighting has a major effect on color appearance so that this study conducted an experiment through a subjective evaluation and luminance measurement for effective color appearance in a space. This study performed a subjective evaluation under the seven different LED CCT conditions, and color appearance was evaluated with major five colors in a customized lighting box. In addition, luminance measurement was conducted for each CCT and color condition to compare the results from a subjective evaluation. The results of this study may help to select a proper LED CCT for specific color conditions.

• 한국인쇄학회:학술대회논문집
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• 한국인쇄학회 2000년도 추계학술발표회 논문집
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• pp.0.2-0
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• 2000

Most important step for the color matching in scanner is the color coordinate transformation from the scanner RGB space to device independent uniform color space. A variety of color calibration technologies have been developed for input device. Linear or nonlinear matrices have been conveniently applied to correct the color filter\`s mismatch with color matching function in scanners. The color matching accuracy is expected to be further improved when the nonlinear matrices are optimized into subdivided smaller color spaces than in single matrix of the entire color space. This article proposed the scanner calibration method using subspace division regression analysis and it were compared with conventional method.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 신호처리소사이어티 추계학술대회 논문집
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• pp.245-248
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• 2003

This parer proposes the six color separation using th color difference and granularity. Conventional method using the color difference increases the graininess in the bright region due to the usage of the cyan or magenta. To reduce the graininess in the bright region, we proposed the six color separation minimizing the graininess within the tolerance of the co]or difference. Initially, granularity is calculated based on the standard deviation of the lightness value and chrominance of the SCIELAB space and is applied to the six color separation using the color difference. Proposed six color separation using the color difference and granularity reduces the graininess in the bright region and obtains the smooth tone.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 1995년도 학술대회
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• pp.69-74
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• 1995

An object color can be seen differently under the various outer illuminants. However, human visual system has color constancy that the object color can be seen constantly under the different outer illuminants. When the viewer watches TV under specific outer illuminants, he perceives distorted color due to the emitting spectrum of outer illuminants as well as the radiation of CPT itself. Namely, when the outer illuminants such as fluorescent and incandescent lamps incident on CPT, brightness, saturation, hue, and contrast on color pictures are changed, he perceives distorted color from the original color. In this paper color enhancement algorithm based on light intensity and outer light decision function using RGB sensor was proposed. The implemented TV of proposed algorithm has higher visual quality at the view point of human visual system and more vivid than that of conventional color TV.

• 한국인쇄학회지
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• 제19권1호
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• pp.4-16
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• 2001

Most important step for the color matching in scanner is the color coordinate transformation from the scanner RGB space to device independent uniform color space. A variety of color calibration technologies have been developed for input device. Linear or nonlinear matrices have been conveniently applied to correct the color filter's mismatch with color matching function in scanners. The color matching accuracy is expected to be further improved when the nonlinear matrices are optimized into subdivided smaller color spaces than in single matrix of the entire color space. This article proposed the scanner calibration method using subspace division regression analysis and it were compared with conventional method.