• Bulletin of the Korean Chemical Society
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• v.31 no.7
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• pp.1981-1987
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• 2010

A novel composite (Ag-CNT/$TiO_2$) of silver treated carbon nanotubes (Ag-CNT) and $TiO_2$ was synthesized via wet chemistry followed by a heat treatment. The dispersion and structure of the silver in the synthesized composites determined by X-ray diffraction (XRD), energy dispersive X-ray (EDX) spectroscopy, scanning electron microscopy (SEM), and transmission electron microscopy(TEM). XRD patterns of the composites showed that the composites contained a mixing anatase and rutile phase. The EDX spectra showed the presence of C, O, Ti and Ag peaks. The $TiO_2$ particles were distributed uniformly in the CNT network, and silver particles were virtually fixed on the surface of the tube. The photocatalysis degraded behaviors of the Ag-CNT/$TiO_2$ composites of the methylene blue, which increased with an increase of the silver component. The Ag-CNT/$TiO_2$ composites have excellent antibacterial activities against Escherichia coli (E. Coli), Pseudomonas aeruginosa (P. Aeru) and Bacillus subtilis (B. Sub) under visible light.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.10 no.4
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• pp.302-308
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• 2000

Stable amorphous calcium carbonate were synthesized from the serial work for the synthetic conditions such as concentration of solution, reaction temperature, aging time and pH of mother liquor. By using this as a precusor, calcite, aragonite and vaterite crystal particles were obtained in the water from adequate crystallization conditions. Furthermore, characterization for flourescence were performed by using crystals which were crystallized from the Sn dopped amorphous calcium carbonate. Calcite showed the most intensive emission and the center of emission wavelength was 464 nm with pure blue color. Calcite is expected to be used as phosphor for flourescent lamp because the maximum emission intensity was obtained from the excitation with 255 nm wavelength.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.29 no.1
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• pp.40-43
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• 2016

Transparent color coating films were fabricated on a glass substrate by using sol-gel hybrid binder and organic dye. Sol-gel hybrid binder coating film fabricated with PTMS of 0.03 mole showed a very high pencil hardness of 9 H. As the withdrawal speed increased from 1.0 mm/s to 5.0 mm/sec, The yellowness ($b^*$) of coating glass also gradually increased. The transmittance of yellow color coating glass was 82.6% and the haze of coating glass was 0.35%. Red and blue color coating glasses also showed the high transmittance of 62.4% and 80.6% respectively. The surface hardness of color coating films was 6 H.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.25 no.5
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• pp.335-347
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• 2013

In February 2008, high storm waves due to a developed atmospheric low pressure system propagating from the west off Hokkaido, Japan, to the south and southwest throughout the East Sea (ES) caused extensive damages along the central coast of Japan and along the east coast of Korea. This study consists of two parts. In the first part, we estimate extreme storm wave characteristics in the Toyama Bay where heavy coastal damages occurred, using a non-hydrostatic meteorological model and a spectral wave model by considering the extreme conditions for two factors for wind wave growth, such as wind intensity and duration. The estimated extreme significant wave height and corresponding wave period were 6.78 m and 18.28 sec, respectively, at the Fushiki Toyama. In the second part, we perform numerical experiments on wave-structure interaction in the Fushiki Port, Toyama Bay, where the long North-Breakwater was heavily damaged by the storm waves in February 2008. The experiments are conducted using a non-linear shallow-water equation model with adaptive mesh refinement (AMR) and wet-dry scheme. The estimated extreme storm waves of 6.78 m and 18.28 sec are used for incident wave profile. The results show that the Fushiki Port would be overtopped and flooded by extreme storm waves if the North-Breakwater does not function properly after being damaged. Also the storm waves would overtop seawalls and sidewalls of the Manyou Pier behind the North-Breakwater. The results also depict that refined meshes by AMR method with wet-dry scheme applied capture the coastline and coastal structure well while keeping the computational load efficiently.

• Journal of Fisheries and Marine Sciences Education
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• v.25 no.6
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• pp.1360-1365
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• 2013

Juvenile sea cucumber, Apostichopus japonicus(wet weight $1.0{\pm}0.2g$, n=250) acclimated to environmental conditions($17^{\circ}C$, 33 psu) during 4 weeks for observation of survival and structural variation of integumentary system according to various salinity concentration. After that, it was exposed 0, 5, 10, 15, 20, 25, 30, 35, 40 psu in 96h, and recovered during 7 days. In this results, The 96-h lethal concentration(LC50) for sea cucumber was a salinity of 21.05 psu. Integumentary system of the sea cucumber exposed to below the salinity of 20 psu mainly observed thickness reduction of epidermal layer, nucleus condensation of epithelial cells, decreased of mucous cells and loose arrangement of connective tissue in dermal layer. Integumentary system of the sea cucumber exposed a salinity of 40 psu mainly observed nucleus hypertrophy of epithelial cells, increase of mucous cells and tight arrangement of connective tissue in dermal layer. Also, observed secretory cells showing the alcian blue(pH 2.5) positive. During 96-h exposure, this cells decreased after increase below the salinity of 20 psu but increased in the salinity of 40 psu compared with 25-35 psu.

• Journal of the korean academy of Pediatric Dentistry
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• v.34 no.1
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• pp.73-80
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• 2007

Compomer that release fluoride could be used on proximal caries of child effectively. But oral cavity is always wet, so saliva inhibits bonding of tooth and compomer. When the saliva exist on bonding, it can be occured microleakages. The purpose of this study was to evaluate the influence of salivary contamination on compomer restoration and degree of microleakage according to restoration methods. Dyract $AP^{(R)}$ and prime and $bond^{(R)}$ NT was applied by the manufacture s instructions. Elipar Trilight was applied for light curing. Saliva pool was made for reconstruction of oral cavity. Two premolar was embedded in acrylic resin. After class II cavity preperation, Dyract $AP^{(R)}$ was restored under several condition, the specimen was thermocycled 500 times with 30 second dwell time. 0.5% methylene blue was used for microleakage test. Micoleakage was measured by the ratio of the infiltration length to occlusal and gingival side interface. Data were analyzed statistically using Kruskal Wallis Test, Mann-Whitney Test. The Result were as follows ; 1. In occlusal side, there were no statistical differences. 2. In gingival side, there were no statistical differences in Group III ($ContactMatrix^{TM}$, Rubber dam, $Oraseal^{(R)}$), Group IV (No saliva contamination). 3. In gingival side, there were no statistical differences in Group I$(ContactMatrix^{TM})$, II($ContactMatrix^{TM}$, Rubber dam). 4. In gingival side, there were statistical differences in Group I$(ContactMatrix^{TM})$, II($ContactMatrix^{TM}$, Rubber dam).

• Conservation Science in Museum
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• v.27
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• pp.125-146
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• 2022

The Wooden Gamsil with Inscription of "Botajeon" in the collection of the Dongguk University Museum was made in imitation of the wooden architecture style of the late Joseon period. The Gamsil had suffered exfoliation in the pigment and loss of components and thus underwent conservation treatment. Prior to the conservation treatment, the damage was classified by type and form, scientific analysis was carried out on the fiber and the species of wood, and portable X-ray fluorescence (P-XRF) analysis was conducted for the pigment component analysis. According to the analyses, Korea Pine(Soft pine) was used for most parts of the Gamsil, Manchurian walnut (Jugalns spp.) was used for the signboard, and the fiber used was identified as rice straw (Oryza sativa). The P-XRF identified white lead and zinc oxide in the white pigment, red lead in the red pigment, ultramarine blue in the blue pigment, and emerald green in the green pigment. For the conservation treatment, contaminants attached to the gamsil were removed by both dry and wet cleaning, detached parts were reattached in their original places, and lost parts were restored.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.6
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• pp.2300-2305
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• 2010

This study was performed about color-contained mud to provide fun and diversity for the event of mud self massage as a core program of Boryeong Mud Festival which has become one of representative festivals in Korea. Adjusting its own lower brightness of mud and based on the primary study performed about the expressivity of yellowish colors, inorganic colors (oxidized steel in red, ultra marine pink, ultra marine blue, chrome oxide green) were added for the development of colored mud in diverse colors on the basis of Korean traditional colors. It had been judged about each expressivity of color by methods of colormeter, naked eyes inspection and feeling of usage, etc. For the color decided, it had been examined about the coloring when it got wet with the cleaning condition so that it can be used for the event of mud self massage as a program of Boryeong Mud Festival to increase diversity of the Festival and also attempted to develope colored mud to show Korean traditional colors.

• Journal of the Korean Society of Costume
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• v.61 no.9
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• pp.84-96
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• 2011

This paper investigates the formative features and the historical meaning of the Korean dress collection held in the Museum of Archaeology and Anthropology in Cambridge. The Museum holds a total of eleven items of koran dresses that were donated by two anthropologists in the first half of the twentieth century. Male dresses consist of a white cotton jacket (Jeogori), a under-vest (Deungbaeja) made of light wisteria rings, a headband (Manggeon) made of horsehair, a broad brimmed top hat (Gat) made of black horsehair gauze, an oilskin cover (Galmo) drawn over the hat in wet weather, and a hemispherical hat box (Gatjib). Female dresses comprise a pink silk jacket (Jeogori), a blue silk skirt (Chima) with pleats, a pair of woman's white cotton trousers (Sokgot), a black silk cap (Jobawi) decorated with pink tassels and imitation pearls, and a pair of green and magenta silk shoes (Danghye) with leather soles and metal rivets. Theses Korean dresses show what the western anthropologists had interests in. When collectors collect the folk objects, they thought much of the specificity of shape and material, the esthetic appreciation, and the representation of daily life. In terms of the value as the historical materials in the history of Korean dress, the under-vest of wisteria, the hat box, and the female dresses are worth paying attention to. The under-vest is one that was produced in earlier time among the remaining under-vests. The hat box represents that the hat belonged to the merchant classes. The female dress items show daily dresses worn by women of higher classes of the society in the 1920s.

• Restorative Dentistry and Endodontics
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• v.29 no.3
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• pp.205-211
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• 2004

This study evaluated the microleakage and interfacial gap between enamel and composite resin under the dry and wet condition of the enamel surface. V shaped class 5 cavities were prepared on the occlusal portion of extracted human molars. Samples were divided into three groups：D group (air dry for 10-15s), BD group (blot dry with moist cotton pellet), and DR group (air dry for 10-15s and rewet with Aqua-Prep F for 20s), Cavities were filled using Aelitefil composite resin after applied One-Step. Microleakage was tested by 2% methylene blue dye solution and the data were statistically analysed by Kruskal-Wallis test and Mann-Whitney test. Also Enamel-resin interface was observed under SEM. Group BD showed statistically lower microleakage than group D (p < 0.05). but there was no statistically significant difference between group BD and DR (p > 0.05). At the enamel-resin interface, group D showed the gap of $2{\;}{\mu}m$ thickness, but group BD and DR showed close adaptation. In conclusion, the use of blot dry and rewetting agent (Aqua-Prep F) resulted in decreased microleakage and improved adhesion between enamel and resin when using One-Step.