• Korean Journal of Optics and Photonics
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• v.14 no.3
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• pp.236-243
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• 2003

We discussed the design of lens module schematic eyes equivalent to finite model eyes, which are used to model the human eye based on spherical aberration and Stiles-Crowford effect. The optical system for head mounted display (HMD) is designed and evaluated using lens module schematic eyes. In addition to a compact HMD system, an optical system with high Performance is required. To satisfy these requirements, we used diffractive optical elements and aspheric surfaces so that the color and mono-chromatic aberrations were corrected. The optical system for HMD is composed of 0.47 inch micro-display of SVGA grade with 480,000 pixels, a plastic hybrid lens for the virtual image, and the lens module schematic eyes. The designed optical system fulfills the current specifications of HMD: such as, EFL of 31.25 mm, FOV of 24H$\times$18V$\times$30D degrees, and overall length of 59.1 mm. As a result, we could design an optical system useful for HMD; the system is expected to be comfortable while the user wears it.

• The Research Journal of the Costume Culture
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• v.30 no.1
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• pp.50-65
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• 2022

The aim of this study was to provide data to enable the development of skateboarding pants. From the Chinese skateboard club SNS, 126 skateboarders in their 20s and 30s were chosen to participate in a survey. Data was gathered using a questionnaire from May 14 to May 28, 2021, and then analyzed using SPSS 23. The results concerning production were as follows: clothing sizes are generally divided into six stages: XS, S, M, L, XL, and 2XL. The silhouette is wide, and most pants have e-bands and normal hems. The pants are made from cotton-blend fabric, which is mostly moisture-absorbing and quick-drying. Baggy pants are preferred by skateboarders, with cotton being the most common fabric. The crotch, knees, and buttocks of pants are the least satisfying for skateboarders. When they skateboard, their ankles sustain the most injuries, followed by their knees and wrists. In the survey of consumers' preferences for skateboarding pants, different styles were rated in the following order: straight pant silhouette, ribbed knit and string waistband design; full-rise waist height, string hemline design; and ankle-high pants length (fit), fabric and design. The hygroscopicity and ventilation of the fabric are crucial considerations when purchasing pants. In terms of color, chromatic and pastel colors are most popular. In addition, some people expect new fibers to be used and expect protective equipment and pants to be integrated.

• Journal of Conservation Science
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• v.25 no.4
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• pp.451-464
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• 2009

To do conservation for ceramics, sometimes it needs to clean the ceramics chemically to remove stains on the ceramics, which should be performed with caution. This study will provide quantitative data about the extraction characteristics of major elements from ceramics through the soaking test to evaluate the stability of ceramic cleaning agents. As soft textured pottery(fired at $700^{\circ}C$) had high absorption, it showed higher extraction characteristics in short soaking time. Especially the strong acid among chemical cleaning agents caused the expoliation and the color change on the surface of soft textured pottery. But these color change had no effect on the physical characteristics of soft textured pottery. The hard textured pottery(fired at $1,000^{\circ}C$) is relatively stable in the cleaning agent because it is ascertained the extraction of that was not enough and also it had little chromatic and physical change by strong acid. Porcelains(Celadon, Whiteware and Puncheong ware) was safer than the soft textured pottery due to their low extraction. But it should take precautions to clean the porcelains with lots of cracklewares such like Puncheong ware chemically in connection with the extraction characteristics and their cracklewares.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.38 no.4
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• pp.392-400
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• 2001

This paper proposes an illuminant estimation algorithm that estimates the spectral power distribution of an incident light source from a single image. The proposed illumination recovery procedure has two phases. First, the surface spectral reflectances are recovered in the maximum achromatic region (MAR) which is the most achromatic and highly bright region of an image after removing partially the effect of illumination using a modified gray world algorithm. Here, the surface reflectances of MAR are estimated using the principal component analysis method along with a set of given 1269 Munsell samples. Second, the Population of reflected lights is determined with 1269 Munsell samples and a set of illuminations then the spectral distribution of re(looted lights of MAR is selected from the spectral database. That is, color differences are compared between the reflected lights of the MAR and the spectral database, which is the set of reflected lights built by the given set of Munsell samples and illuminants. Then the closest colors from the spectral database are selected. Finally, the illuminant of an image can be calculated dividing the average spectral distributions of reflected lights of MAR by the average surface reflectances of the MAR. In order to evaluate the proposed algorithm, experiments with artificial scenes, which are exposed to chromatic illuminants, were performed and the spectral distribution of estimated illumination and color difference are compared with results of the conventional method.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.2
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• pp.323-327
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• 2014

This study was carried out to provide basic data on the anion, element, chromatic and antioxidant activities of commercial dried lavers cultivated from Seocheon, Wando, Goheung and Busan in Korea. The highest concentrations of several anions ($Cl^-$, $NO_3{^-}$, $SO_4{^2-}$, and $PO_4{^3-}$ per 100 g of dried laver) were 412.00 mg in Wando, 545.90 mg in Goheung, 297.35 mg in Seocheon, and 79.70 mg in Wando, respectively. The highest concentrations of N, C, and S were 6.40%, 41.36%, and 0.98%, respectively, in dried laver cultivated from Wando. Hunter's color values were significantly high in the order of Seocheon < Goheung < Busan < Wando for lightness, Wando < Busan < Goheung < Seocheon for redness, and Goheung < Seocheon < Busan < Wando for yellowness in the dried lavers. Total phenolic content and DPPH (1,1-diphenyl-2-picryl-hydrazyl) radical scavenging activities showed highest values of 166.10 mg/100 g and 28.48%, respectively, in dried laver cultivated from Wando.

• Food Science of Animal Resources
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• v.29 no.3
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• pp.334-339
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• 2009

This study was carried out to determine the effects of olive-oil prepared tomato powder (OPTP) and lycopene on seasoned raw pork. 1.5% OPTP was added in T1 and 3.0% in T2; and 0.03% refining lycopene was added in T3. While in storage, pH values of the treated samples were lower (p<0.05) than those of the control samples. Upon increasing storage, salinity values of OPTP samples increased as well, however, the values of T3 did not change. There were significantly higher TBARS values observed in the OPTP samples compared to control, but no significant difference between T3 and the control samples in TBARS values during storage. VBN values of T2 samples were lower than that of other samples at Day 3 and Day 6 of storage. At Day 9 however, the VBN values of T1 and T2 were significantly higher than those of the control and T3. There was no significant difference between the control and the treated samples in the total plate counts. There were relatively higher redness, yellowness and chromatic values observed in the treated samples than in control. In sensory evaluation, there was no significant difference between the control and the treated samples in color, tenderness, juiciness and overall acceptability.

• Restorative Dentistry and Endodontics
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• v.21 no.2
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• pp.530-545
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• 1996

The purpose of this study was to investigate by spectrophotometry the changes in color parameters of composite resins after exposure to distilled water, filtered coffee, and artificial saliva. Five kinds of fine particle composite resin in experiment 1, and six kinds of composite resin in experiment 2 were used. In experiment 1, each group of composite resin was stored in distilled water at $4^{\circ}C$, $50^{\circ}C$, and filtered coffee solution at $4^{\circ}C$, $50^{\circ}C$. And then each specimen was measured by spectrophotometer. Measurements were repeated in 1 hour, 2 hours, 4 hours, 8 hours, 16 hours, 24 hours, and 48 hours. In experiment 2, all specimens of each brand were stored in distilled water at $37^{\circ}C$, artificial saliva not contained mucin at $37^{\circ}C$, and artificial saliva contained mucin at $37^{\circ}C$. All specimens of each brand were measured by spectrophotormeter in 1 week, 2 weeks, 4 weeks, 8 weeks, and up to 12 weeks. The results were as follows : 1. In cold coffee, five of fine particle composite resins showed ${\Delta}E{^*}_{ab}$ values less than 2. However, in hot coffee ${\Delta}E{^*}_{ab}$ values of Amelogen Universal and Prisma TPH were higher than those of Conquest Crystal, ${\AE}$litefil and Z100. 2. Z100 and ${\AE}$litefil had better cleansibility of extrinsic coffee staining than Amelogen Universal, Conquest Crystal and Prisma TPH. 3. In distilled water and artificial saliva not contained mucin, five of fine particle composite resin showed ${\Delta}E{^*}_{ab}$ values less than 2 up to 12 weeks. However, Silux Plus showed higher than ${\Delta}E{^*}_{ab}$ values of fine particle composite resin. 4. As an immersion solution for discoloration experiment, artificial saliva not contained mucin showed similar appearance as distilled water. However, artificial saliva contained mucin had different appearance from the others. 5. In artificial saliva contained mucin, ${\AE}$litefil, Prisma TPH and Z100 showed ${\Delta}E{^*}_{ab}$ values less than 1 up to 12 weeks. However, Silux Plus, Amelogen Universal and Conquest Crystal showed ${\Delta}E{^*}_{ab}$ values more than 1 up to 12 weeks. But, Conquest Crystal showed different characteristics of chromacity difference value(less chromatic) and lightness difference value(lighter) from Silux Plus and Amelogen Universal.