• Journal of Surface Science and Engineering
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• v.50 no.6
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• pp.523-530
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• 2017

In this study, we developed the h-BN interphase for ceramic matrix composites (CMCs) through a wet chemical coating method, which has excellent price competitiveness and is a simple process as a departure from the existing high cost chemical vapor deposition method. The optimum condition for nitriding an h-BN interphase using boric acid and urea as precursors were derived, and the h-BN interphase coating through a wet method on a carbon preform of 2.5 D was conducted to apply the optimum conditions to the CMCs. In order to control the coating property via the wet coating method, four parameters were investigated such as dipping time of the specimen in the precursor solution, the ratio of boric acid and urea in the precursor, the concentration of solution where the precursor was dissolved, and the cycle of dipping and dry process. The CMCs was fabricated through polymer impregnation and pyrolysis (PIP) processes and a three-point flexural strength test was conducted to verify the role of the coated h-BN interphase.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.44 no.6
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• pp.50-57
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• 2012

In this study, the beeswax extraction methods using organic solvents were examined to develop a optimal dewaxing technology for beeswax-treated Hanji. Thermally-aged beeswax-treated Hanji was dewaxed using four types of extraction methods including dipping, Soxhlet extraction, ultrasonic washing and shaking methods. Then, the aging stability of the dewaxed Hanji was evaluated in terms of variations in paper strength and in the color of the printed area with muk. The experimental results suggested that the dewaxing methods allowing solvent to flow during extraction showed superior extraction efficiency. The dipping method in which the organic solvent does not flow showed the slowest extraction rate of beeswax compared to three other methods. In terms of variations in tensile strength and folding endurance, however, no obvious differences in the aging stability were observed amongst these four extraction methods. Regarding the aging stability in terms of the color of the printed area with muk, Soxhlet extraction method showed the best performance of dewaxing.

• Journal of Applied Biological Chemistry
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• v.57 no.4
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• pp.301-305
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• 2014

The Antioxidant activity screening identification of five kind compounds in Artemisiae annuae herba with the on-line screening high performance liquid chromatography (HPLC) $ABTS^+$ assay. The various experimental variables such as the extraction time (h) and extraction solvent composition (%) of dipping method were investigated efficiently extraction at the room temperature $25^{\circ}C$. The results, the highest yield of total extract amount (0.458 g, 15.250%) was obtained by dipping method with 100% water and extraction time to 3 h. And the on-line screening HPLC-$ABTS^+$ assay method was rapid and efficient to search for bioactivity from natural products.

• Economic and Environmental Geology
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• v.12 no.1
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• pp.1-12
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• 1979

A model study was conducted for the interpretation of simple geologic structures. Experiments were carried out for the cases of two horizontal beds and dipping beds in a water tank by using Wenner and Schlumberger arrays respectively. As a geologic stratum of experimental model, cement be (cement: sand=1:2) of $70cm{\times}60cm{\times}10cm$ was used. It was found out from a preliminary experiment that a measuring sounding of Wenner arrays is one third of the distance between two current electrodes, and Schlumberger arrays is one fourth of the distance which is a half of the value determined by usual method of calculation. Equi-resistivity curves were obtained for the cases of horizontal beds and dipping beds, and mapped on the longitudinal and cross sections of the water tank. These curves delineate the shape and degree of dip of bed to some extent. The calculation of depth to beds by using a master curve is somewhat complicated and inexact. In this study, new method for this calculation using a ${\rho}_a/{\rho}_1-a$ graph was proposed, and turned out that this method is simpler and exact.

• Journal of the Korea Society for Simulation
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• v.20 no.2
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• pp.59-66
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• 2011

In this paper, a method to allocate a submarine search mission to an ASW(Anti-Submarine Warfare) helicopter is proposed. The aim of the proposed method is to increase the submarine detection capability. For this purpose, we modeled the behaviors that the ASW helicopter conduct during the search mission, and the relations between the behaviors are also modeled. To measure quantitatively the effectiveness of ASW search mission, the measure of effectiveness(MOP) is defined. Scenarios are designed to analyze the effectiveness utilizing the ASW mission model. We conducted simulations applying the designed scenarios and some parameters concerned with the friendly ship and the enemy submarine interacting each other in the ASW missions. We analyzed the result of simulation depending on the dipping interval and the pattern of dipping positions in the situation that the helicopter operates for a long time and should resupply several times on the friendly ship. From the analyzed data, we suggested the practical value of ratio between the detectable range of the sonar and the dipping interval to improve the effectiveness of ASW mission.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.6 no.6
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• pp.25-28
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• 2003

This study was conducted to development of rapid propagation method by leaf cuttings in Hibiscus hamabo native to southern seaside of Korea, and special object of this study was to determine the effects of IAA, IBA, and NAA on rooting in leaf cuttings of H. hamabo. Rooting was promoted by dipping treated with IAA and IBA. And rooting percentage was greatest at 1,000 and 2,000$mg{\cdot}L^{-1}$ IBA. At higher concentrations of IAA and IBA, more adventitious roots were developed. Also, IAA at high concentrations (above 2,000$mg{\cdot}L^{-1}$) and IBA ranged from 500~2,000$mg{\cdot}L^{-1}$ promoted on root number and rootingratio. However, root formation in Hibiscus leaf cuttings inhibited by NAA application.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.2
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• pp.111-118
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• 2001

Tungsten probe is the most important part of a probe card, which is widely used for the performance test of wafer chips. Electro chemical etching becomes an exclusive choice for mass production of the tungsten probes. In the mass production, not only the shape of the probe but also the shape distribution of machined probes is important. A new method is proposed for the mass production of the tungsten probes. Tungsten wires are separated by a distance, and dipped into electrolyte. The dipping rate is controlled to shape the probes. Several experimental tests are performed to study the machining characteristics. From the test results, machining parameters including electrical conditions and anode position showed significant influences on the shape, repeatability, precision and quality of sharp tips.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2015.05a
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• pp.128-129
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• 2015

Al-rich coatings were prepared on hot rolled low carbon steel by hot dipping method in molten Al-bath to investigate the corrosion resistance with the possible outcomes and defects of aluminized coatings in air and $Ar-0.2%SO_2$ mixed gases. Coating microstructure was composed of an inner Al-Fe intermetallic layer and outer Al-rich layer. Aluminum oxidized preferentially to the thin, outer, protective ${\alpha}-Al_2O_3$ layer, without forming the nonprotective iron/sulfur-oxide layer after heating at $800^{\circ}C$ for 20 h, in both the gases and provided the resistance against corrosion.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2015.05a
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• pp.122-122
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• 2015

Al-rich coatings were prepared on hot rolled low carbon steel by hot dipping method in molten Al-bath to investigate the corrosion resistance with the possible outcomes and defects of aluminized coatings in air and $Ar-0.2%SO_2$ mixed gases. Coating microstructure was composed of an inner Al-Fe intermetallic layer and outer Al-rich layer. Aluminum oxidized preferentially to the thin, outer, protective ${\alpha}-Al_2O_3$ layer, without forming the nonprotective iron/sulfur-oxide layer after heating at $800^{\circ}C$ for 20h, in both the gases and provided the resistance against corrosion.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.10
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• pp.1517-1522
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• 2002

The effect of post milking teat dipping on somatic cell count (SCC) of milk was determined in 20 Crossbred cows and 20 Murrah buffaloes selected from institute's herd. The animals were divided into two groups of 10 each. Animals of Group I (control) were teat washed with water before the milking while Group II animals were applied teat dipping solution after the completion of milking. The cows were milked 3 times a day while buffaloes were milked twice a day. The milk samples were collected from control and treated animals on day 0, 5, 10, 15, respectively. The milk samples were analyzed for milk constituents like fat, protein, lactose, chloride, IgG, NEFA, pH and EC and total and differential somatic cell counts. The changes in milk composition and somatic cell counts were significantly different (p<0.01) between the animals and between the breeds. However SCC, chloride content (p<0.05) and epithelial cells (p<0.01) varied during different days of study. The alterations in SCC, epithelial cells, TLC, lymphocyte, neutrophil, IgG, and protein content were significantly different (p<0.01) between control and treated groups. The pH, EC, protein, SCC, epithelial cells, lymphocyte and neutrophil cells of milk declined significantly (p<0.05) after the application of teat dipping, the respective values were 6.5 vs 6.40, 2.28 vs 2.37 mhos, 3.33 vs 4.04%, 1.00 vs $0.87{\times}10^5cells/ml$, 0.39 vs 0$0.34{\times}10^5cells/ml$, 0.36 vs $0.31{\times}1,000cells/ml$ and 0.17 vs $0.14{\times}1,000cells/ml$ in cows. However in buffaloes, epithelial cells, lymphocytes, neutrophils, EC and SCC declined (p<0.05) after application of teat dipping, the values being 0.37 vs $0.29{\times}10^5cells/ml$, 0.37 vs $0.25{\times}1,000cells/ml$, 0.14 vs $0.11{\times}1,000cells/ml$, 2.56 vs 2.37 mhos and 0.94 vs $0.73{\times}10^5cells/ml$, respectively. The study indicated that post milking teat dipping could be used as an effective method for the lowering of SCC in milk of crossbred cows and buffaloes.