• Journal of Technologic Dentistry
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• v.4 no.1
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• pp.5-7
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• 1982

This study was performed to examine the effect of repeated firing on porcelain color stability. Sixty sepcimens of generally uniform size and shape(9.7 12mm)were prepared using the manufactorer's specifications and among them 50 specimens that showed no defect after firing procedure were selected. All samples, abraded with sandpaper disc, ultrasonically cleaned, and air fired to amedium glaze were devided into 10 groups according to the number of repeated firing and, upon completion, mounted on a 13 by 16cm board. 30 persons(five dentists, ten dental techanicians, and fiftheen students) were asked to compare the samples for variations, in hue, chroma and value under natural and artificial light. The results were as follows:(1) There were no color change detected in the first four firings.(2) Slight color change were noticed in subsequent firings(ie: greater decreases in value with slight increases In chroam)(3) However, the hue remained constant in all 10 groups after repeated firings.

• Journal of The Korean Society of Grassland and Forage Science
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• v.5 no.2
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• pp.162-166
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• 1985

• Journal of the Korean Society of Industry Convergence
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• v.1 no.2
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• pp.65-74
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• 1998

The purpose of this paper is to investigate the mount of relief of human solar heat load and thermal comfort in outdoor environment in summer, Six different types of sites, T garden and its neighboring area in Japan, were selected as the experiment sites. The experiments were conducted from 22 to 29 August, 1994 to find the relationship between climatic conditions and human responses, Climatic conditions, subjects's thermal sensation and skin temperature were measured. Radiant heat exchange on the human body was estimated on the basis of the measured air and surface temperature and solar radiation. Thermal index Operative Temperature and New Effective Temperature was modified with the effect of the radiant heat exchange. Human thermal comfort and skin temperature is affected by the solar radiation and the sky factor in an outdoor environment. The effect of tree shade was verified on thermal comfort, The mount of relief of human solar heat load is relation to the existence of shade a solar radiation and the sky factor. The urban garden is one of the effective design element in an urban environmental planning.

• The Journal of Advanced Prosthodontics
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• v.5 no.4
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• pp.448-451
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• 2013

PURPOSE. Translucency of all-ceramic restorations is an important factor which affects the final appearance and esthetic outcome of the restoration. The aim of this study was to evaluate the effect of the shade of coloring liquid on the translucency of zirconia framework. MATERIALS AND METHODS. Thirty zirconium oxide core plate ($15{\times}12{\times}0.5$ mm) were divided into 6 groups of 5 plates each. Each group was classified according to the shade of coloring liquid based on Vita Classic Scale (A2, A3, B1, C2, and D2), and each sample was immersed in coloring liquid for 3 seconds as recommended by the manufacturer, except for the control group. Contrast ratio, as a translucency parameter, was calculated using a spectrophotometer and the data were analyzed with oneway analysis of variance (ANOVA) and Tukey's honestly significant differences (HSD) tests (${\alpha}$=.05). RESULTS. Significant differences in translucency among the control and test groups, and the B1 shaded group and other shades was observed. There were no significant differences among A2, A3, C2, and D2 shaded groups. CONCLUSION. The translucency of the zirconium oxide cores was affected by the coloring procedure and significant differences in the translucency measurements were identified between specific shades.

• Restorative Dentistry and Endodontics
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• v.34 no.2
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• pp.154-161
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• 2009

This clinical study evaluated the whitening effect and safety of polymer based-pen type BlancTis Forte (NIBEC) containing 8.3% carbamide peroxide. Twenty volunteers used the BlancTis Forte whitening agent for 2 hours twice a day for 4 weeks. As a control. Whitening Effect Pen (LG) containing 3% hydrogen peroxide was used by 20 volunteers using the same protocol. The change in shade (${\Delta}E^*$, color difference) was measured using $Shadepilot^{TM}$ (DeguDent) before, during, and after bleaching (2 weeks, 4 weeks, and post-bleaching 4 weeks). A clinical examination for any side effects (tooth hypersensitivity or soft tissue complications) was also performed at each check-up. The following results were obtained. 1. Both the experimental and control groups displayed a noticeable change in shade (${\Delta}E$) of over 2. No significant differences were found between the two groups (p > 0.05), implying that the two agents have a similar whitening effect.2. The whitening effect was mainly due to changes in a and b values rather than in L value (brightness). The experimental group showed a significantly higher change in b value, thus yellow shade, than the control (p < 0.05). 3. None of the participants complained of tooth hypersensitivity or soft tissue complications, confirming the safety of both whitening agents.

• Asian Journal of Turfgrass Science
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• v.18 no.3
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• pp.129-139
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• 2004

This study conducted to find out the best way to prolong green period of Zoysiagrass and Cool-season grass from 1999 to 2001 in Korea. Treatments were control, vinyl, black shade net, green shade net, black shade net+vinyl, green shade net+vinyl, vinyl+black shade net, and vinyl+green shade net for Zoysiagrass. For cool-season grass, treatments were control, non-punched vinyl and punched vinyl. Data on temperature, light intensity, humidity, leaf color and chlorophyll were collected. Plot size was 2 by 2 and the experiment was conducted using completely randomized design with three replication. Zoysiagrass Green period of Zoysiagrass depended on temperature and light intensity than humidity. Effective method of prolongation of green period in Zoysiagrass was to covered it with vinyl during early October to early November, and then using vinyl+black shade net from end of November. Cool-season grass Effective method of prolongation of green period in Cool-season grass was by covering it with vinyl during mid-November to mid-December, and then using vinyl+black shade net from end of December.

• The Journal of the Korean dental association
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• v.49 no.4
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• pp.203-210
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• 2011

The aims of this study were to evaluate the adequate thickness of opaque resins for situations such as an oral black cavity and discolored tooth structure, as well as the translucency of each opaque material at various thicknesses. Six opaque-shade composite resins (Z-350 OA3, Amelogen Universal A2O, Esthet-X A2O, Esthet-X A4O, Charmfil UO and Aelite Universal OA3) were prepared in metal molds with a hole of 8 mm in diameter and various thicknesses (0.5mm, 1.0mm, 1.5mm, 2.0mm, 2.5mm, 3.0 mm and 4.0mm). Four backgrounds (white tile, black tile, C4 shade porcelain and opaque resin itself) were used to determine the translucency parameter (between black and white backgrounds). and to mimic a black oral cavity (between black and opaque resin backgrounds) and a discolored tooth structure (between C4 and opaque resin backgrounds). Color measurements were made by a colorimeter to determine the CIELAB values of each specimen with each background and to calculate the translucency parameter and ${\Delta}E^*$ value difference among the specimens on the backgrounds. The translucency parameter and ${\Delta}E^*$ obtained between black and opaque resin backgrounds decreased in similar pattern as thickness increased. A C4 background was masked by resin thicknesses of 0.5-1.0mm, while a black background required thicknesses of 1.0-2.0mm. Adequate knowledge about differences in the optical character like translucency of the materials used is essential, together with the accumulated experience of the individual clinician.

• 한국태양에너지학회:학술대회논문집
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• 2008.04a
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• pp.196-202
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• 2008

Effective climate protection is a most important tasks of our time. The BIPV is one of the most interesting and promisingly possibilities of an active use of solar energy at the building. In this study it was analyzed by the case study the function of the requirement of the BIPV-module as building material and this architectural characteristic according to the kind of the module. Therefore the goal of this study is to get securing the application information of BIPV as windowpane. BIPV modules are manufactured in the form of G/G. In the case of the crystal type the Transparent and the light Transmission is to be adjusted by the spacer attitude of the cell. Although this type could not be optimal for light effect of indoors because of the inequality of shade, the moving shade play makes a dramatic Roomimage by the run of sun. The application of this type would be for canopy, window or roof in the corridor or resounds. With amorphous the type it is to be manufactured simply largely laminar, and thus that will shorten building process. There is a relatively good economy to use and to the window system easily. After the production technology is easy the transparency of the modules to adjust, and the module shows to a high degree constant characteristics of light permeability and transparency. Without mottle of module shade is good the use for the window or roof glazing of office, library, classroom, etc. to adapt. The BIPV modules took generally speaking a function as building material to the daylight use, shading, isolation and also to the sight. That means that BIPV modules have as multifunctional system to sustainable architecture good successes and they are at the same time as Design element for architecture effectively.

• International Journal of Oral Biology
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• v.41 no.4
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• pp.243-251
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• 2016

This study was undertaken to achieve a high bleaching efficacy with plasma, through longer application and reparative bleaching processes, by different shade evaluation methods. Extracted human teeth were divided into 6 groups (n=10). All teeth were treated in pairs. Low concentration of 15% carbamide peroxide (CP) was applied, with and without plasma, for 10, 20, and 30-min tooth bleaching, respectively. The bleaching procedure was repeated once daily for four days. The teeth were maintained in a moist environment provided by artificial saliva. The Vitapan Classical shade guide and Commission Internationale de L'Eclairage (CIELAB) color system were collectively used to measure the bleaching efficacy. Color evaluation was statistically analyzed using Student t-test and one-way analysis of variance (ANOVA) complemented by Tukey's test. Combining the plasma with 15% CP showed significantly greater color changes compared to bleaching without plasma (p<0.05). A high bleaching efficacy with plasma is proportional to the repetitive application and the treatment time. A 30-min application with plasma provided the best bleaching. Repetitive bleaching showed lower probability of color relapse of the bleached tooth. The color change by shade guide correlated with the changes in CIELAB color system. A value of 1 color change units (CCU) conversion factor for overall color change (${\Delta}E$) values comparisons was 3.724 values. The two measuring methods provide a more accurate correspondence of color change. The repetitive and longer application for tooth bleaching, combined with plasma, has a strong bleaching effect and produces whiter teeth.

• Korean Journal of Environmental Agriculture
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• v.28 no.2
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• pp.106-112
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• 2009

The increased $CO_2$ and temperature (700 ${\mu}$mol.$mol^{-1}$ $CO_2$ and $30^{\circ}C$) was compared with ambient growth conditions (400 ${\mu}$mol.$mol^{-1}$ $CO_2$ and $25^{\circ}C$) in hot pepper. Gas exchange measurements, including net photosynthesis ($P_{net}$) and stomatal conductance ($g_s$), were taken according to treatment in fields of peppers grown in Suwon and Asan during 2008. The increased treatment $P_{net}$ by 35-45% throughout the season and was statistically significant in t-tests (p < 0.001); however, it did not significantly affect $g_s$. In addition, the gas exchange parameters in sun and shade leaves were measured. The difference between the sun and shade leaves was much greater than that between the elevated and ambient treatments, especially at harvest. Four commercial cultivars of hot pepper, Chunhasangsa, Ryukang, Manitta, and Olympic, were also compared by ANOVA. Chunhasangsa had the highest $P_{net}$, which decreased by 30% from the vegetative to the harvest stage. Based on a factorial design, the effect of the increased $CO_2$ and temperature was assessed based on the temperature, $CO_2$, and their interaction effects. Orthogonal contrasts showed that the effects of temperature on $P_{net}$ and $g_s$ were significant, whereas $CO_2$ and their interactions were not.