• Journal of the Korean Society of Clothing and Textiles
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• v.44 no.1
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• pp.68-83
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• 2020

This study suggests a method to predict the color appearance of textiles that shifts depending on illumination variations. The suggested method allows the calculations of lightness, chroma, and hue appearance values from the spectral reflectance values of the textile and illuminant. The accuracy of the method was evaluated through numerical and statistical comparisons between the predicted and the measured color appearance values of 24 fabric samples under CIE standard illuminant D65. As a result, there were excellent agreements between the two data sets with the error values close to zero. The predicted color appearance values of 24 samples under two illuminating (color temperature-luminance) conditions, 2700 K-100 cd/㎡ and 6500 K-100 cd/㎡, were then compared to prove the significant effect of illumination on the color appearance of textiles. The color appearance values were also compared with spectrophotometrically measured physical color attributes, that is, true colors of the samples. The physical color attributes of samples were unchanged; however, differences in color appearance under different conditions were generally much larger than the suprathreshold color difference tolerances discussed in the color science literature. Finally, the magnitude of the illumination effect depending on the physical color attributes of samples was also analyzed.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.57 no.1
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• pp.88-97
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• 2024

The underwater color environment was assessed by conducting color calculations based on underwater spectral irradiance measurements at various depths. Changes in the distribution of underwater spectral irradiance values between 1 and 3 m, exhibited similar trends in areas Stn. 1, 5, and 6. Likewise, changes between 5 and 20 m displayed comparable patterns in areas Stn. 1, 2, 4, and 6. Color values for each observed area fell between 0.14 and 0.26 (x-values) and 0.2 and 0.36 (y-values), with the y-values exhibiting a variation 1-3 times greater than the x-values. Color a_* and b_* values ranged from a maximum of -17 and -6 to a minimum of -63 and -30, respectively. By classifying fishing grounds based on observed variations, Stn. 1, 9, Stn. 2, 3, Stn. 7, 8 and Stn. 4, 5, 6 were grouped independently. Particularly, Stn. 5, 6, 7, and 8 were categorized into distinct groups that could be visually differentiated, especially when considering the significant changes in color a_* as the water depth increased from 10 to 20 m. Tokyo Bay were classified into different color groups, and Wakayama Prefecture offshore was classified into the same color group as the surveyed fishing grounds.

• Journal of Intelligence and Information Systems
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• v.25 no.1
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• pp.109-125
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• 2019

As interest on intelligent search engines increases, various studies have been conducted to extract and utilize the features related to products intelligencely. In particular, when users search for goods in e-commerce search engines, the 'color' of a product is an important feature that describes the product. Therefore, it is necessary to deal with the synonyms of color terms in order to produce accurate results to user's color-related queries. Previous studies have suggested dictionary-based approach to process synonyms for color features. However, the dictionary-based approach has a limitation that it cannot handle unregistered color-related terms in user queries. In order to overcome the limitation of the conventional methods, this research proposes a model which extracts RGB values from an internet search engine in real time, and outputs similar color names based on designated color information. At first, a color term dictionary was constructed which includes color names and R, G, B values of each color from Korean color standard digital palette program and the Wikipedia color list for the basic color search. The dictionary has been made more robust by adding 138 color names converted from English color names to foreign words in Korean, and with corresponding RGB values. Therefore, the fininal color dictionary includes a total of 671 color names and corresponding RGB values. The method proposed in this research starts by searching for a specific color which a user searched for. Then, the presence of the searched color in the built-in color dictionary is checked. If there exists the color in the dictionary, the RGB values of the color in the dictioanry are used as reference values of the retrieved color. If the searched color does not exist in the dictionary, the top-5 Google image search results of the searched color are crawled and average RGB values are extracted in certain middle area of each image. To extract the RGB values in images, a variety of different ways was attempted since there are limits to simply obtain the average of the RGB values of the center area of images. As a result, clustering RGB values in image's certain area and making average value of the cluster with the highest density as the reference values showed the best performance. Based on the reference RGB values of the searched color, the RGB values of all the colors in the color dictionary constructed aforetime are compared. Then a color list is created with colors within the range of ${\pm}50$ for each R value, G value, and B value. Finally, using the Euclidean distance between the above results and the reference RGB values of the searched color, the color with the highest similarity from up to five colors becomes the final outcome. In order to evaluate the usefulness of the proposed method, we performed an experiment. In the experiment, 300 color names and corresponding color RGB values by the questionnaires were obtained. They are used to compare the RGB values obtained from four different methods including the proposed method. The average euclidean distance of CIE-Lab using our method was about 13.85, which showed a relatively low distance compared to 3088 for the case using synonym dictionary only and 30.38 for the case using the dictionary with Korean synonym website WordNet. The case which didn't use clustering method of the proposed method showed 13.88 of average euclidean distance, which implies the DBSCAN clustering of the proposed method can reduce the Euclidean distance. This research suggests a new color synonym processing method based on RGB values that combines the dictionary method with the real time synonym processing method for new color names. This method enables to get rid of the limit of the dictionary-based approach which is a conventional synonym processing method. This research can contribute to improve the intelligence of e-commerce search systems especially on the color searching feature.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07a
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• pp.85-88
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• 2005

A low-cost and high-speed PDP color inspection system can be constructed by using a CCD camera against a colorimeter. Though the inspection can be done using RGB signals obtained by a camera, it has some difficulty to introduce human color sensitivity. Thus, it is quite desirable to convert the RGB values into the XYZ values that can be compared to the values of a colorimeter. Accordingly, the current study proposes a color conversion method that can analytically calculate the RGB-to-XYZ conversion matrix by utilizing the RGB primaries and the reference white. Experiments on Macbeth colorchecker colors showed that the average color difference between the converted XYZ values of the proposed method and the measured XYZ values of a colorimeter is much below the threshold of distinguishing two adjacent color patches.

• Journal of Fashion Business
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• v.11 no.1
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• pp.1-14
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• 2007

This study was aimed at giving help to the people intending to change their own hair color design and also providing the guide line to the cosmetic circles for developing new hair color design and promoting sales by statistically analyzing seasonal changes of hair colors puplished on women's magazines(Vogue Korea, Estetica Korea, Woman Chosun, Ce.ci) from 2003 to 2006. The researching methods were as follows; (1) hair colors published on women's magazines from september 2003 to August 2006 were measured by N.C.S. color reader(4 magazines $\times$10 main hair colors/magazine $\times$ 12 months $\times$ 3 years = 1,440 colors). (2) N.C.S. tone is made of percentage, so measured values and chromas were statistically analyzed by mean, standard deviation, and seasonal deferences were statistically analyzed by t-test and specified on high significant values. But hues were not made of percentage, so these were statistically analyzed by cross tabulation analysis, $x^2$ -test and specified on high significant values. These all had been analyzed by SPSS program(ver. 11.0). The results were as follows; (1) Usually seasonal changes of hair values were significant, specially in foreign licensed magazines, and bright values appeared in S/S and dark values in F/W. (2) Seasonal changes of hair hues were significant only on foreign women's magazines. Therefore seasonal changes of korean hair colors were not significant compared by foreign hair colors because of hardness of color changes of dark black hair and hair damages by hair tints and bleaches and trends of well being and hair care. But hair color changes have been developed gradually and will developed furthermore. So korean hair cosmetic circles have to present hair color trends deferenciated by seasons. And S/S hair values have to be brignt and F/W have to be dark. And new seasonal hair hues matched by korean have to be developed and presented.

• Journal of Korean Dental Science
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• v.8 no.2
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• pp.49-56
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• 2015

Purpose: The effect of accelerated aging on color stability of various dual-cured self-adhesive resin cements were evaluated in this study. Materials and Methods: Color stability was examined using three different brands of dual-cured self-adhesive resin cements: G-CEM LinkAce (GC America), MaxCem Elite (Kerr), and PermaCem 2.0 (DMG) with the equivalent color shade. Each resin cement was filled with Teflon mold which has 6 mm diameter and 2 mm thickness. Each specimen was light cured for 20 seconds using light emitting diode (LED) light curing unit. In order to evaluate the effect of accelerated aging on color stability, color parameters (Commission Internationale de l'Eclairage, CIE $L^*$, $a^*$, $b^*$) and color differences (${\Delta}E^*$) were measured at three times: immediately, after 24 hours, and after thermocycling. The $L^*$, $a^*$, $b^*$ values were analyzed using Friedman test and ${\Delta}E^*$ values on the effect of 24 hours and accelerated aging were analyzed using t-test. These values were compared with the limit value of color difference (${\Delta}E^*=3.7$) for dental restoration. One-way ANOVA and Scheff's test (P<0.05) were performed to analyze each ${\Delta}E^*$ values between cements at each test period. Result: There was statistically significant difference in comparison of color specification ($L^*$, $a^*$, $b^*$) values after accelerated aging except $L^*$ value of G-CEM LinkAce (P<0.05). After 24 hours, color difference (${\Delta}E^*$) values were ranged from 2.47 to 3.48 and $L^*$ values decreased and $b^*$ values increased in all types of cement and MaxCem Elite had high color stability (P<0.05). After thermocycling, color change's tendency of cement was varied and color difference (${\Delta}E^*$) values were ranged from 0.82 to 2.87 and G-CEM LinkAce had high color stability (P<0.05). Conclusion: Color stability of dual-cured self-adhesive resin cements after accelerated aging was evaluated and statistically significant color changes occurred within clinically acceptable range.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.4
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• pp.641-646
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• 1994

changes in HMF content, capsanthin content, Hunter tirstimulus values, color-preference, and pruchasing intent were investigated during storage of industry-produced kochujang packed with polyethylene and nylon complex film at 13, 27 and 37$^{\circ}C$. HMF content, which was very low at initial , did not showed significant increase during storage at 13$^{\circ}C$ for 180 days, but the accumulation of HMF was accelerated by higher temperature. Capsanthin content decreased more rapidly at higher temperature . L values decreased up to 60 days of storage and the storage temperature had little influence on the rate . But, after 60 days, L value decreased more slowly at 13 than at 27 and 37$^{\circ}C$ , a and b values showed linear decrease at 37$^{\circ}C$, but increase in a and b values at 13 and 27 $^{\circ}C$ during early storage was followed by decrease. ΔE decreased more rapidly at higher temperature . Color-preference and purchasing-intent for kochujang decreased during storage at 27 and 37 $^{\circ}C$, but did not show significant changes during storage at 13 $^{\circ}C$ for 180 days. L, and ΔE values of kochujang stored at 37 and 27Δ showed positive correlation with color-preference, but Hunter tristimulus values of Kochujang stored at 13$^{\circ}C$ did not show not any significant correlation with color preference.

• Korean Institute of Interior Design Journal
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• no.27
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• pp.3-11
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• 2001

The CMYK is the mathematical color model and the Musell system is an intuitive color model. CMYK color model needs to be proposed in the information age. These two models need to be integrated for convenience of color design. This paper deals with CMRK values, which have appeared in interior design, in association with the Munsell code. Firstly, color samples have been extracted from the cases of interior design. Secondly, the CMRK values of the color sample and the Munsell code have been found. Thirdly, relationship between the CMRK values has been formularized in comparison with the Whelan's color pallette by using the regression method. This paper concludes by proposing the formular which can be used to develope color palette in further research.

• Journal of the Korean Academy of Esthetic Dentistry
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• v.6 no.1
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• pp.10-17
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• 1997

It is pointed out that the color of composite resin is changing according to it's ploymerization and this color change is a harmful effect for the clinical satisfacion of composite resin restoration. The purpose of this study was to compare the changes of color of newly developed composite resins between before and after exposure of activating light. Five Compostie resins (8 shades) were employed: Palfique Estelite(UL, U, DY, G ; Tokuyama), Photo Clearfil A (US : Kuraray), Photo Clearfil Bright (US ; Kuraray), GC Graft LC(A3 ; GC), Silux Plus(U; 3M), Tristirnulus values of each material were determined before and after curing-light exposure by using a Micro Multi Photometer (MMP-1001, Nihon Denshoku Kogyo). The values were transformed into $L^*\;a^*\;b^*$ system and color changes of the resins were evaluated by the changes of $L^*$, $a^*$ and $b^*$ values for the individual shades. In addition, the effects of resin thickness and background color on color changes were also studied The finding were as follows: 1. Color changes of $L^*$, $a^*$ and $b^*$ values were recognized due to the light exposure for all products. The $b^*$ values of Palfique Estelite showed negligible changes for all shades. 2. The $b^*$ values were affected strongly by the background color, especially when decreasing the brightness on the background color.(Request original article reprints to Dr. Aoshima)

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.2
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• pp.274-278
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• 1994

Correlation between pH and color of Kimchi during fermentation was investigated to visually evaluate the fermentation degree of Chinese cabbage Kimchi. Color "a" and 'H" values in the white part, "a", "H" and "C" values in the green part of the Kimchi showed a high correlation with pH, respectively. "a" and "H" values of Kimchi juice. "L" and "V" values of red pepper attached to kimchi had a high correlation with pH. The color of the white part was light greenish white in unripended Kimchi, but changed to redish in ripended kimchi. Green part changed from light green to redish green as ripening. Red pepper powder attached to kimchi showed redish color in unripening, but changed to yellowish re din over ripening.