• The Journal of Korean Academy of Prosthodontics
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• v.47 no.1
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• pp.1-11
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• 2009

Statement of problem: There are two methods of color choice for the esthetic restoration. One is visual shade matching which draws a comparison between shade guide and teeth in dentist's own eye and the other is using a digital shade analysis system recently introduced. Although the visual shade matching has a lot of problems, decision of color by this visual shade matching and the ways of expression for the decided color are still applicable to clinical dentistry. Purpose: This study is designed to investigate shade guides used in the dental clinics and laboratories have the same value using ShadeEye-$NCC^{(R)}$ dental chroma meter (Shofu Inc., Kyoto, Japan) using shade guide are evaluated. Material and methods: At the first experiment, eight Vita Lumin Vacuum shade guides (Vident Inc., California, USA) were collected from the dental clinics. A1 and B1 shade tabs are chosen and the colors are analyzed five times each in both tooth and porcelain modes by digital shade analysis system, ShadeEye-$NCC^{(R)}$. In the second experiment, twelve Vita shade guides using practically in the dental clinics and laboratories were collected and also A1 and B1 shade tabs are chosen and the colors of A1 and B1 are analyzed one time each in both tooth and porcelain modes by ShadeEye-$NCC^{(R)}$. Results and conclusion: There were significant differences among eight shade guides in terms of shade (chroma), value and hue in both of A1 and B1 (P<.05). Shade guides using in present both dental clinics and laboratories did not show significant differences, except A1 in the porcelain mode, it showed significant differences (P<.05) in the shade even though the shade tab has the same name.

• Proceedings of the SCSK Conference
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• 2003.09a
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• pp.178-191
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• 2003

OMC is essentialiy necessary compound in sun goods as organic UV protecting products. But the skin-trouble problem is raising because of skin penetration of OMC. In this study, non-capsulated pure OMC was compared with Organic-Inorganic-Nano-hybrid OMC for skin penetration force and SPF degree. Organic- Inorganic Nano-Hybrid OMC is OMC trapped in the pore of the mesoporous silica synthesized by the sol-gel method after OMC is nanoemulsified in the system of the hydrogenated Lecithin/ Ethanol/caprylic/capric triglyceride/OMC/water. OMC- nano- emulsion was obtained by a microfluidizing process at 1000bar and then micelle size in the nanoemulsion solution is 100-200nm range. Mesoporous silica nano-hybrid OMC was prepared by the process; surfactant was added in dissolved OMC-Nanoemulsion, then the rod Micelle was formed. OMC-nanoemulsion was capsulated in this rod Micelle and then silica precursor was added in the OMC-nanoemulsion solution. Through the hydrolysis reaction of the silica precursor, mesoporous silica concluding OMC-Nanocapsulation was obtained. The nano-hybrid surface of this OMC-Nanoemulsion-Inorganic system was treated with polyalkyl-silane compound. OMC-Mesoporous silica Nano-hybrids coated with polyalkyl-silane compound show the higher sun protecting factor (SPF Analyzer: INDEX 10-15) than pure OMC and could reduce a skin penetration of OMC. The physico-chemical properties of these nano-hybrids measured on the SPF index, partical size, strcture, specific surface area, pore size, morphology, UV absorption, rate of the OMC dissolution using SPF Analyzer, Laser light scattering system, XRD, BET, SEM, chroma Meter, HPLC, Image analyzer, microfluidizer, UV/VIS. spectrometer.

• Journal of the Korean Society of Costume
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• v.54 no.7
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• pp.79-90
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• 2004

In this study we tried to find the skin color of Koreans according to the change of seasons, and to the degree of make-up used by men and women. in order to furnish foundation data that could be used in the cosmetics and clothes industries. The skin color was measured with Minolta's Chrome Meter CR-200 in seven parts of the body with Munsell's hue, value, chroma. The difference in skin color in men and women's groups, and the difference in skin color of each group in March and in September were treated with SPSS's Anova and t-test. 1. In both seasons. March and September, a big difference could be observed between the two groups (men and women's). The body was more yellowish than the face. The men's group had a reddish skin color than the women's groups. In all groups we could observe a big difference in color between seasons, and in March, the skin was more reddish whereas in September, it became more yellowish. 2. As for the value, both in March and in September, the hairline was darkest, and the lightest areas were the jaw and the inner arm which showed a similar value. The group of women who put on make-up had the highest value, whereas the men's group showed the lowest result in value. We suppose it to be due to the fact that Putting on make-up prevented the melanin pigmentation by blocking the UV rays. 3. We could observe the highest value in chrome in the chin area both in March and in September, and there was no significant change. There was a difference in men and women's groups, but not a significant one within the women's groups.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.7 no.4
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• pp.19-25
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• 1993

The purpose of this study was to investigate the scope of color perception for Korean standard color. 99 male and 126 female university students were selected as the random sample. Color perception was made with the naked eyes. Minolta Chroma Meter CR 300 was used for physical measurement of the color. The results were as follows, 1) Color perception was classified into four large groups: simple group includes Red, Yellow Red, Pale Red Yellow, Yellow, X( -axis)group includes Pale Yellow Red, Pale Green Yellow, Green Yellow, Purple, Pale Red Purple, Y( -axis)group includes Pale Blue Green, Blue Green, Pale Green Blue, Blue, Pale Ptuple Blue, complex group includes Pale Yellow Green, Green, Purple Blue, Pale Blue Purple, Red Purple, Pale Purple Red. 2) There is little difference between the values of standard color and mean percept color for Blue, Yellow, Pale Green Yellow, Green Yellow, Pale Yellow Green, Green, Pale Blue Green, Blue Green, Purple, while big difference for Blue, Pale Green Blue, Pale Red Purple, Pale Purple Red. 3) As for as sex was concerned, female is more accurate than male in color perception.

• KIPS Transactions on Software and Data Engineering
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• v.2 no.2
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• pp.145-150
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• 2013

A film colored overlay has been used as an assistive device for dyslexics, Recently, several virtual colored overlays which can be used in computer were developed. But mobile virtual overlay has not been developed yet. In this paper, I implemented a mobile overlay application which is based android operating system and displays a colored overlay of screen all the time while user can freely interact with rest of apps in normal manner by using root window and service. A method is presented to determine the source color of a virtual overlays by estimating alpha value of alpha blending algorithm through measurement of the chromaticity and transmissivity of film overlays and I implemented all colors which are presented by using Intuitive Overlays. Test results of the developed virtual overlay show that all colors of the overlays are almost identical to the colors of Intuitive Overlay by using the chroma meter CS-200A.

• Journal of Life Science
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• v.17 no.12
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• pp.1754-1759
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• 2007

This study is performed to assess the preparation and characterization of lactic acid bacteria (Sterpoccoccus thermophilus) loaded with alginate microsphere using alginate and chitosan for the efficient delivery of lactic acid bacteria to large intestine. Size and morphology of alginate microsphere were confirmed $6{\sim}10{\mu}m$ with spherical shape by scanning electronic microscope (SEM). Biodegradation study of alginate was investigated at different buffer solutions (pH 1.2 and 7.4). This result showed that alginate microsphere did not degrade at pH 1.2 buffer solution but it's degradation occurred from first day at pH 7.4 buffer solution. Survivability test of lactic acid bacteria in alginate microsphere showed that it was keeping activity of lactic acid bacteria by chroma meter. Therefore, the introduction of alginate microsphere might be a potential system to efficiently delivery lactic acid to large intestine.

• Journal of Dental Rehabilitation and Applied Science
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• v.29 no.1
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• pp.81-93
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• 2013

The objectives were to evaluate the accuracy of shade selection by human visual system(VS) and 2 different colorimeters ($ShadeEye^{(R)}$(SE) and Shadepilot (SP)). Maxillary anterior teeth of 30 volunteers which had no caries or restorations were included in the study. Firstly, the accordance in shade selection by 3 dentists and 2 colorimeters was investigated. Secondly, the color of the teeth were measured by 1 observer's naked eye and 2 colorimeters under different illumination conditions (Sunny versus cloudy day). Additionally testing of inter-observer variability selected colors by 2 novice and 2 experienced dentists were compared. For comparing visual and 2 different colorimeters, SP(60%) showed significantly highest rate of accordance than the visual (23.3%) or SE (16.7%) and lowest mean ${\Delta}E$ ($2.62{\pm}0.74$ versus $3.83{\pm}1.38$;SE or $4.04{\pm}1.61$;VS)(p<0.001). If accuracy of shade selection were measured using VS, the mean ${\Delta}E$ value of cloudy day was higher than that of sunny day ($4.35{\pm}1.70$ versus $3.53{\pm}1.31$; p<0.001). There were no significant difference of the mean ${\Delta}E$ value between sunny and cloudy day in both SE and SP. Inter- observer repeatability was higher in 2 experienced group (73.3%) than novice group (36.7%). The mean ${\Delta}E$ of experienced group was lower than that of novice group ($3.60{\pm}1.47$ versus $4.70{\pm}1.67$; p<0.001). Colorimeters (SE or SP) is more accurate and more reproducible compared with human shade assessment. Using visual system may be limited by cloudy and inexperience of tester, then more experience and using colorimeters may be helpful of raising the accurate repeatability of shade selection.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.30 no.2
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• pp.201-205
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• 2004

In these several years, as many people have been attracted by the functional cosmetics, there are a lot of study to enhance the stability of active ingredients for light, heat, oxygen, etc. in the academic and industrial field. Especially, catechin is well known as strong anti-oxidant, anti-inflammatory and reducing agent for oxidative stress but it is very unstable for light, heat, oxygen. etc. In this study, the stability and skin penetration of catechin are improved by 3-dimensional method. As I-dimension, porous silica is prepared using sol-gel method, and then catechin is adsorbed in pores of silica. As 2-dimension, solid lipid nanoparticles (SLN) are obtained using non-phospholipid vesicles. Finally 3-dimension is completion through lamellar phase self-organization that combines SLN catechin with skin lipid matrix. We used laser light scattering system, cyro-SEM, chromameter, HPLC and image analyzer to analyze our 3-dimentional systems. According to chromameter date, the color stability of 3-dimensional catechin is enhanced by 5-10 times compared with general liposome systems. We also confirmed through HPLC analysis that 3-dimensional catechin is more long lasting. The effect of skin penetration and wrinkle reduction are improved, too.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.17 no.1
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• pp.10-16
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• 2003

The purpose of this study was to investigate the scope of standard color perception for Americans and to compare the differences in color perception between Korean and American undergraduates. Sixty male and fifty-one female American undergraduates were selected as a random sample. Color perception was tested with the naked eyes. Minolta Chroma Meter CR 300 was used for physical measurement of the color. Based on the objective of this study and the data generated the following results were drawn: 1) We found no distinctive difference in color perception by different eye colors. 2) Color perception of American undergraduates is largely classified into four different groups: simple group includes Yellow, Green, Blue, White, Gray, and Black, X(-axis)group includes Yellow Red, Y(-axis)group includes Blue Green, Purple, complex group includes Yellow Red, Purple Blue. 3) The differences in color perception between the two undergraduate groups were found to be significant with four colors: Yellow Red, Green, Blue, and Purple. 4) There is a wide difference between the values of standard color and inn percept color. When undergraduates in both countries were compared, it turned out that Korean students were more accurate than Americans in color perception. 5) American students perceived Red, Yellow, and Green colors relatively correctly, but showed an extremely low degree of accuracy in Blue and Purple Blue color perception.

• Restorative Dentistry and Endodontics
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• v.35 no.5
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• pp.387-394
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• 2010

Objectives: The purpose of this study was to evaluate the whitening efficacy and longevity of home bleaching. Materials and Methods: A total of 28 patients were divided into either experimental group (Opalescence F; 15% carbamide peroxide) or control group randomly. The patients in experimental group were instructed to wear individual trays applied with bleaching gel for 2 hours a day for 4 weeks. Any treatments weren't applied to the patients in control group. The color measurements of central incisors, lateral incisors & canines of upper and lower arch were recorded at base line, immediately after the finishment of treatmemt (4 weeks), 8 weeks and 12 weeks using Colorimeter (Chroma Meter, 2600d Konica Minolta co.) and Vitapan classical shade guide (Vita Zahnfabrik). Results: A significantly stronger color change was observed for overall teeth samples in experimental group immediately after treatment (at 4 weeks) compared to ones in control group (p < 0.05). There was also a significant difference between baseline and 8 weeks or 12 weeks separately though color rebouncing phenomenon occurred as time went by (p < 0.05). Conclusions: The clinical effecacy and longevity of home bleaching without combined application of in-office bleaching was observed through this experiment.