• The Bulletin of The Korean Astronomical Society
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• v.40 no.2
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• pp.50.1-50.1
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• 2015

The origin of globular cluster (GC) color bimodality, which is one of the salient phenomena observed in most large galaxies, has not yet been fully resolved. The phenomenon has conventionally been interpreted as a bimodal metallicity distribution based on an assumption of linear GC color-metallicity relations (CMRs). Recent studies however suggest that nonlinear GC CMRs can cause a bimodal color distribution even from a single-peaked metallicity spread. Using photometric and spectroscopic data on GCs in NGC 5128 (Cen A) and NGC 4594 (Sombrero), we investigate the nonlinearity of GC CMRs and compare the observed GC CMRs with the predictions of stellar population simulation models. Our careful selection of old GCs effectively reduces the scatter and reveals the nonlinear nature of the GC CMRs for various colors. The overall shape of the observed CMRs agrees well with that of the modeled CMRs, while offsets are present for some colors. We discuss the implications of our results in terms of the GC color bimodality and GC formation in NGC 5128 and NGC 4594.

• Journal of the Korean Graphic Arts Communication Society
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• v.16 no.3
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• pp.121-131
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• 1998

The object color does not look same under the different light source. It depends on the surface spectral reflectance and the spectral distribution of light source. Therefore we should find the surface spectral reflectance of object color and the spectral distribution of light source for color reproduction. Using Wiener estimation, we can estimate the spectral reflectance from low dimensional images obtained with multi-band image acquisition system. The kind and the number of imaging filters have the effect on the estimation of the spectral reflectance. Therefore it is important that optimal filters are selected to minimize the error of the result. In this paper, we describe methods to select optimal filters with minimum error between measured and estimated surface spectral reflectance and to estimate surface spectral reflectance of Munsell color chart from six multi-band images by using Wiener estimation.

• Proceedings of the Korean Printing Society Conference
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• 1998.10a
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• pp.1-6
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• 1998

The object color does not look same under the different light source. It depends on the surface spectral reflectance and the spectral distribution of light source. Therefore we should find the surface spectral reflectance of object color and the spectral distribution of light source for color reproduction. Using Winer estimation, we can reconstruct the spectral reflectance from low dimensional images obtained with a few filters. The kind and the number of filters have the effect on the estimation of the spectral reflectance. Therefore it is important that optimal filters are selected to minimize the error of the result. In this paper, we describe methods to select optimal filters with minimum error between measured and estimated surface spectral reflectance and to estimate surface spectral reflectance of Munsell color from six band images by using Wiener estimation.

• Korea Science and Art Forum
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• v.26
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• pp.179-187
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• 2016

The purpose of this study is to analyze the color environment of urban small parks. We selected the urban small parks located in the subway stations around the line 2 and the Yamanote line in Seoul and Tokyo, and measured the environmental color with a spectroscopic colorimeter. Four urban parks, four urban parks, four urban parks, four urban parks, and four urban parks in Tokyo, and conducted field surveys. The study was divided into social sports facilities, park facilities and floor paved areas. The results of the study are as follows. The color of Y, YR, and GY colors were high in the environmental color of the first sports facilities in Seoul and Tokyo. In the case of Seoul, B, BG, PB, and Tokyo are R and P series, respectively. econd, in the case of social sports facilities, Tokyo has a different color distribution than Seoul, and Seoul has a somewhat higher brightness, so bright colors have been applied to the facilities. Third, the colors of park facilities showed similar brightness and saturation values in Seoul and Tokyo. In color distribution, Seoul is higher in Y-series and B-series, and Tokyo is higher in Y-series and R-series. The brightness and the saturation of the bottom pavement are similar to those of Seoul and Tokyo. However, the difference in color distribution shows that the color difference of the social facilities of urban small parks in Seoul and Tokyo varies depending on the color distribution rather than brightness and saturation.

• Journal of Korea Multimedia Society
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• v.12 no.5
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• pp.633-643
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• 2009

We propose a color transfer method that used color contrast based templates to express the visual difference clearly between objects, while remaining the quality of the input image. Our algorithm employs colors of both the input image and template distributed on the $a^{\ast}b^{\ast}$chrominance plane of CIE $L^{\ast}a^{\ast}b^{\ast}$color space. The templates are made by considering the effect of color contrast and have the shape of either a line or a curve represented color distribution of the basic colors based gradation image. These tempates can be modeled on spline curves. We also generate simply new templates with the different basic colors by moving the control points of that curve. The color transfer method using the templates is done through a regressive analysis and color matching. We maintained color coherence of the input image by transforming similarly the color distribution of an input image to the one of templates.

• Journal of The Institute of Information and Telecommunication Facilities Engineering
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• v.9 no.2
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• pp.73-79
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• 2010

The most popular technique for image retrieval in a heterogeneous collection of color images is the comparison of images based on their color histogram. The color histogram describes the distribution of colors in the color space of a color image. In the most image retrieval systems, the color histogram is used to compute similarities between the query image and all the images in a database. But, small changes in the resolution, scaling, and illumination may cause important modifications of the color histogram, and so two color images may be considered to be very different from each other even though they have completely related semantics. A new method of color feature representation based on the 3-dimensional RGB color map is proposed to improve the defects of the color histogram. The proposed method is based on the three 2-dimensional projection map evaluated by projecting the RGB color space on the RG, GB, and BR surfaces. The experimental results reveal that the proposed is less sensitive to small changes in the scene and that achieve higher retrieval performances than the traditional color histogram.

• Journal of information and communication convergence engineering
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• v.2 no.2
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• pp.123-127
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• 2004

The most popular technique for image retrieval in a heterogeneous collection of color images is the comparison of images based on their color histogram. The color histogram describes the distribution of colors in the color space of a color image. In the most image retrieval systems, the color histogram is used to compute similarities between the query image and all the images in a database. But, small changes in the resolution, scaling, and illumination may cause important modifications of the color histogram, and so two color images may be considered to be very different from each other even though they have completely related semantics. A new method of color feature representation based on the 3-dimensional RGB color map is proposed to improve the defects of the color histogram. The proposed method is based on the three 2-dimensional projection map evaluated by projecting the RGB color space on the RG, GB, and BR surfaces. The experimental results reveal that the proposed is less sensitive to small changes in the scene and that achieve higher retrieval performances than the traditional color histogram.

• Journal of The Korean Astronomical Society
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• v.38 no.3
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• pp.345-355
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• 2005

We present a photometric study of the star cluster system in the merging galaxy NGC 1487, based on the BI photometry obtained from the F450W and F814W images in the HST /WFPC2 archive data. We have found about 560 star cluster candidates in NGC 1487, using the morphological parameters of the objects. We have investigated several photometric characteristics of the clusters: color-magnitude diagrams (CMDs), color distribution, spatial distribution, age, size and luminosity function. The CMD of the bright clusters with 18.5 < B < 24 mag in NGC 1487 shows three major populations of clusters: a blue cluster population with $(B-I){\le}0.45$, an intermediate-color cluster population with $0.45<(B-I){\le}1.55$, and a red cluster population with (B - I) > 1.55. The intermediate-color population is the most dominant among the three populations. The brightest clusters in the blue and intermediate- color populations are as bright as $B{\approx}18mag$ ($M_B{\approx}-12mag$), which are three magnitudes brighter than those in the red population. The blue and intermediate-color clusters are strongly concentrated on the bright condensations, while the red clusters are relatively more scattered over the galaxy. The CMD of these clusters is found to be remarkably similar to that of the clusters in the famous interacting system M51. From this we suggest that the intermediate-color clusters were, probably, formed during the merging process which occurred about 500 Myrs ago.

• Development and Reproduction
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• v.15 no.4
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• pp.325-329
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• 2011

The main objective of this study is to investigate the distribution of coat color among Ulleung Korean Native Brindle Cattle, and to identify basic genetic elements required for the fixation of coat color traits. 1. The distribution of coat color among Ulleung Korean Native Brindle Cattle was 24.3% yellow (67/276),13.0% black (36/276), 62.7% brindle (173/276). The frequency of Brindle coat color was slightly higher (66%, 105/159) among embryo transfer from outside than that of cows produced by embryo transfer from jurisdiction. 2. Investigation of coat color distribution in each sex group showed that the frequency of yellow coat color was lower in males (18.1%, 25/138) than in females (31.4%, 43/137). On the other hand, the frequency of brindle coat color was slightly higher among males (68.1%, 94/138) than in females (56.9%, 78/137). 3. Examination of Brindle coat color expression based on the intensity of black dots on the nose indicated that the expression of black coat color increase in proportion to the intensity of black dots.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.66 no.4
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• pp.350-357
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• 2021

In the present study, the seed color of 200 common bean genetic resources was analyzed and located on the HTML color chart to classify these resources according to color characteristics. This classification method predicts the components of seed and may serve as a new method for efficiently using secured genetic resources. The imagary data of common bean exhibiting various seed colors were expressed using the HTML color chart. According to the proposed classification method, the seed color was distributed in seven categories: yellow-green, yellow, brown, red, white, gray, and indigo. In addition, the distribution of each seed color was according to its concentration. The distribution by concentration was the highest for red, whereas the distribution of gray and yellow-green was not concentration-dependent. As the dominant pigments based on color distribution, chlorophylls in yellow-green; carotenoids in yellow; and anthocyanins in brown, red, white, gray, and indigo significantly affected seed color. When expressed objectively, seed colors can be applied to the systematic management, breeding, and cultivation of genetic resources and can be useful for marketing or developing products of desired colors. This method can also be applied to other crops.