• Journal of Periodontal and Implant Science
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• v.31 no.3
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• pp.501-511
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• 2001

Several indices have been developed that use bleeding and color changes as indicators of early gingival pathology. In the presence of gingivitis, vascular proliferation and reduction of keratinization owing to increase redness in gingiva. Descriptions of healthy gingiva are numerous, ranging from pale pink and coral pink to deep red and violet. This terms are not objective. Because of perception of color depends on a lot of factors such as light source, object, observer and so on. It is difficult to make an objective expression. Therefore the using of mechanical equipment is recommended to exclude these variables and observer's vias. The purpose of this study was to evaluate gingival color change after scaling & subgingival root planing. The other purpose of this study was to research the correlation of pocket depth, P.B.I. score and gingival color change. After photo-taking and storaging the image of gingival color into a computer, color change was examine with an image analysis program. Results were as follow; 1. Color of healed gingiva after scaling & subgingival root planing was significantly differ from color of inflamed gingiva(p<0.01). 2. Color of healed gingiva after scaling was similar to color of healed gingiva after subgingival root planing(p<0.05). 3. There was statistically significant correlation between color change of red component and pocket depth after scaling & subgingival root planing(p<0.01). 4. There was no correlation between color change of green, blue component and pocket depth after scaling & subgingival root planing(p<0.01). 5. There was statistically significant correlation between between color change of red component and P.B.I. score after scaling & subgingival root planing(p<0.01). 6. There was no correlation between color changes of green, blue component and P.B.I. score after scaling & subgingival root planing(p<0.01). 7. Increase of pocket depth and P.B.I. score were significantly correlated to the amount of color change(p<0.01). 8. P.B.I. score had a higher correlation with color change than pocket depth(p<0.01).

• The Journal of Korean Academy of Prosthodontics
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• v.37 no.3
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• pp.343-357
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• 1999

The color change of maxillofacial silicone has been attributed to certain environmental factors such as exposure to the UV component of natural sunlight, wetting and drying of the elastomer and surface abrasion resulting from the application and removal of cosmetics. The purpose of this study was to evaluate the color change of maxillofacial silicone (Silastic MDX4-4210) according to type of pigment (cadmium yellow, titanium white, cosmetic red), and UV absorber application method after 200, 400, and 600 hours of 350nm UV light irradiation. The results were as follows. 1. According to type of pigments, after 200 hours cosmetic red showed significantly larger color change than cadmium yellow and titanium white, and after 400 and 600 hours color change significantly decreased in the order of cosmetic red, cadmium yellow, and titanium white (p<0.05). 2. In the cadmium yellow group, after 200 hours, the non-treatment group showed significantly larger color change, but after 400 and 600 hours, color change significantly decreased in the order of non-treatment, surface application and mixed group (p<0.05). 3. In the titanium white group, there was no significant color change difference between the three groups after 200 and 400 hours, but after 600 hours, the mixed group showed significantly smalt or color change than the non-treatment and surface application groups (p<0.05). 4. In the cosmetic red group, there was significant decrease in color change in the order of non-treatment, surface application and mixed group (p<0.05). From the results above, the effect of UV light absorber differed according to the type of pigment, but mixing UV light absorber with maxillofacial silicone is thought to give superior resistance against UV light irradiation in the long run.

• The Journal of Korean Academy of Prosthodontics
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• v.40 no.2
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• pp.172-183
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• 2002

This study is going to compare the degree of color change which occurs in the following two cases of the factors which cause the color change of extra-staining, one is during glazing by the dental technician, the other is tooth brush abrasion which makes the biggest influence on color change. To compare the degree of color change before and after glazing, a sample was made with vintage incisal porcelain No. 59 OPAL(Shofu Inc, Japan), after that it was painted with three colors of porcelain stainers, then the degree of color was measured with a spectrophometer(Model Chromaview 300, Spectoron Tech Co. Korea) after it had been treated with firing only and glazing after firing 40,000-cycle and 80,000-cycle of tooth brush abrasion test were carried out in order to simulate the brushing effect of 4 years and 8 years by using the abrasion tester. The colors were measured before the test, and after the 40,000-cycle and 80.000-cycle operations and the surfaces were examined by SEM. The results of this study were as follows ; 1. The color change before and after glazing was not great enough to have a clinical significance but the orange color was changed more significantly statistically than the blue and light brown(p<0.05). 2. In the case of the color change of stained porcelain by tooth brushing, carrying out staining and glazing with two-times firings resulted in statically less color change than one firing only(p<0.05). 3. In the case of the difference in the stainer's color, the orange color which has higher chroma was statically more sensitive than the blue color(p<0.05) 4. In the case of the color change after the 80,000-cycle abrasion, all showed color change when there was one firing and the orange stainer showed some color change with clinical significance when firings were done two times.

• Korean Institute of Interior Design Journal
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• v.15 no.2 s.55
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• pp.166-173
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• 2006

Architectural color has been preserved the multiple characteristics reflected the change of social value criteria and technical development. Especially, the change of technical paradigm has led to variation from simple and fixed color system, as through the considerable change of architect's subject thinking, favored and symbolic system. Now, architectural color has also been revealed as the timely, moving, behavioral and existent color by anthropolatric thinking system. Therefore, it could be transformed expressive system reflected from abstract-pictorial characteristics, from the fixed to non-determining system, constructive to non-constructive system, context to expressive system, reasonal to emotional system, respectively. So, the range of architectural color has been extended as a element in reinforced the planned concept of the architect beyond the past decorated and symbolic color scope. As thereinafter, future's architectural color could be expected to concrete to the public-friendly relation system, developed widely to the system for reinforcing the concept not introduction of meaningless, fragmental and instinct color through the relational adaptation with design concept.

• Journal of the Korean Ceramic Society
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• v.53 no.4
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• pp.450-455
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• 2016

Color change in single-crystal, yellow, red, purple, and colorless cubic zirconias (CZs) was investigated as a function of annealing in vacuum and air atmosphere at $800-1400^{\circ}C$ for 30 min, for development of a damascene process of plugging a precious metal paste at the elevated temperature. Coloring-element contents of the CZs were evaluated using WD-XRF, and the color change determined visually by naked eye, and using a digital camera and UV-Vis-NIR color analyzer. WD-XRF showed that all of the CZs had cubic-phase stabilizer elements and coloring elements. All CZs that underwent vacuum annealing exhibited a slight color change at $<900^{\circ}C$, while their colors began to change to black at $1100^{\circ}C$, and became opaque black at $1400^{\circ}C$. After air annealing, there was almost no color change up to $1400^{\circ}C$. Since red and purple CZs showed greater color difference (CD) values than the others, the degree of CD is likely to depend on the original color of the CZ due to the different stabilities of their coloring elements during annealing. Based on our results, it is suggested that annealing in air at $<900^{\circ}C$ is advantageous, and assorted colored CZs can be used for precious metal damascene.

• Journal of Environmental Impact Assessment
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• v.22 no.4
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• pp.389-395
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• 2013

Geostationary Ocean Color Imager(GOCI), the World's first spaceborne ocean color observation satellite operated in geostationary orbit, was successfully launched on May 2010. The main missions of GOCI is the coastal environment monitoring of GOCI in order to meet the necessity of long-term climate change monitoring and research. The GOCI have higher spatial resolution than MODIS, $500m{\times}500m$, and 8 spectral ocean color channels. GOCI have a capability for observation on the coastal environment change, GOCI perform the observation with 8 times a day. In this paper, we presented the more improved results for observation on the coastal environment change than MODIS ocean color sensor and detected the spatial difference of CDOM for monitoring coastal environment change.

• Journal of the Korean Society of Clothing and Textiles
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• v.20 no.3
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• pp.429-437
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• 1996

This paper surveys extraction condition-temperature, pH, and changes of adsorbance in accordance with extraction condition of curcuma Longa L. solution. Using extracted curcuma Longa L. Solution, dyeing behaviors with natural fiber, effect of mordants to color fastness and color change were investigated. It was found that the amount of absorption (K/S value) was increased by mordants (Fe, Cr) and mordants treatment affected color change of dyed fabric. Among the mordants, effect of citric acid to color change of dyed fabric was the smallest, and color difference of post- mordant treatment is smaller than that of pee-mordant treatment in making use of citric acid as mordant. And K/S value of post mordant was higher than that of pre mordant. It was found that the pre - and post- mordants treatment little affected color fastness, but affected the amound of adsorption and color change of dyed fabric.

• The Journal of Korean Academy of Prosthodontics
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• v.38 no.1
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• pp.73-84
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• 2000

Dental porcelain should have adequate strength and similar esthetics as natural teeth. Recently esthetics has become a high priority in clinical dentistry. Thus the evaluation of color stability of dental porcelain has become an important part in dental research. The purpose of this study was to evaluate the difference in color stability of 3 types of porcelain(Vintage, VMK 95, CERAMCO II). The porcelain were divided into groups by 2 types of treatment(glazing or non-glazing and thermocycling or non-thermocycling). The porcelain were dyed with methylene blue and distilled water, and then the color stability was evaluated with a spectrophotometer The results were as follows; 1. The color change of porcelain increased in the order of VMK 95, Vintage, CERAMCO II. But there was no significant difference. 2. The color change decreased in the glazing group compared to the non-glazing group(p<0.05). 3. The color change increased after thermocycling But there was no significant difference. 4. The color change according to dye method was significantly larger with methylene blue copared to distilled water(p<0.05).

• Korean Institute of Interior Design Journal
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• v.16 no.5
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• pp.89-97
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• 2007

This study compares, analyzes and reevaluates color conditions and images before and after the execution of the 7th curriculum with elementary schools in Gwang-ju Metropolitan City based on the fact that color among physical environments of elementary classrooms has an important influence on children's emotion and draws problems and aims to accumulate the basic materials for preparing guidelines of improving color environment at general classrooms of elementary schools. Consequently, according to color conditions, major colors on ceiling and wall were high brightness/nigh chroma of Y and YR line regardless of division of grades and other color factors of classroom showed that wall and ceiling used similar colors, but brightness was higher after change than before it. In evaluation of color images, lower grades showed negative color images such as 'common,' 'rustic,' and 'strange' before change, but they showed positive color images after change such as 'clean,' 'unique,' and 'soft'. But, most of higher grades showed negative reactions before change such as 'common,' 'strange,' and 'rustic' and they showed positive reactions after change only in such items as 'clean,' 'warm,' and 'unique', but Indicated negative reactions in remaining items such as 'strange,' 'rustic,' 'stiff,' and 'artificial'. Accordingly, in using colors for lower grade classroom, arrangement of colors through adjustment of brightness and chroma between ceiling, wall and other components based on coloring of high brightness and low chroma of similar colors should be considered and for higher grade classroom, arrangement of colors of unique images of mid-brightness/mid-chroma among warm color lines of similar colors should be examined.

• The Journal of Advanced Prosthodontics
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• v.6 no.4
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• pp.309-316
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• 2014

PURPOSE. The color of the ceramic restorations is affected by various factors such as brand, thickness of the layered the ceramic, condensation techniques, smoothness of surface, number of firings, firing temperature and thickness of dentin. The aim of this study was to evaluate the color change and surface roughness in dental porcelain with different thicknesses during repeated firings. MATERIALS AND METHODS. Disc-shaped (N=21) metal-ceramic samples (IPS Classic; Ivoclar Vivadent; Shaar, Liechtenstein) with different thickness were exposed to repeated firings. Color measurement of the samples was made using a colorimeter and profilometer was used to determine surface roughness. ANOVA and Tukey tests with repeated measurements were used for statistical analysis. RESULTS. The total thickness of the ceramics which is less than 2 mm significantly have detrimental effect on the surface properties and color of porcelains during firings (P<.05). CONCLUSION. Repeated firings have effects on the color change and surface roughness of the dental ceramics and should be avoided.