• Korean Journal of Medicinal Crop Science
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• v.11 no.2
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• pp.161-166
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• 2003

Korean ginseng(Panax gmseng C.A. Meyer) is very difficult to obtain stable production of qualified ginseng roots because of variable stresses in soil environments. In environment stresses, soil condition is the most important factor, among which nutrients, especially inorganic materials such as N, P, K, Ca, Mg, Fe, etc., influence greatly on the ginseng growth. However, present ginseng field soils in Korea contain so much amount of such inorganic materials that a variety of remarkable disorders were noted in many ginseng plantations, resulting in decrease of qualitative ginseng production. Therefore, it is required to search for genetic resources and genes tolerant to salt stress for the development of ginseng cultivars. Selection of stress-tolerant ginseng lines in fields is very difficult because it is almost impossible to control properly the environmental conditions of soil. On the contrary, it can be studied with ease to search for stress-tolerant ginseng lines through in vitro culture because of easy manipulation of stress conditions. Murashige & Skoog(MS) media with 2.5 folds of $KNO_3,\;NH_4NO_3,\;MgSO_4\;7H_2O,\;KH_2PO_4,\;and\;CaCl_2\;2H_2O$ was established for the selection of ginseng lines tolerant to salt stress under the embryo culture.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.16 no.3
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• pp.291-299
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• 2018

Under a pyro-processing concept, an electrolytic reduction process has been developed to reduce uranium oxide in molten salt by electrochemical means as a part of spent fuel treatment process development. Accordingly, a model based on electrochemical theory is required to design a reactor for the electrolytic reduction process. In this study, a 1D model based on the phase-field theory, which explains phase separation behaviors was developed to simulate electrolytic reduction of uranium oxide. By adopting parameters for diffusion of oxygen elements in a pellet and electrochemical reaction rate at the surface of the pellet, the model described the behavior of inward reduction well and revealed that the current depends on the internal diffusion of the oxygen element. The model for the electrolytic reduction is expected to be used to determine the optimum conditions for large scale reactor design. It is also expected that the model will be applied to simulate the integration of pyro-processing.

• Korean Journal of Environmental Agriculture
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• v.20 no.5
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• pp.317-324
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• 2001

Short-term effect of phosphogypsum on soil properties including acidification, salinity and metal availability were investigated under laboratory and field conditions. Phosphogypsum and mixtures of phosphogypsum and compost were added to soil and incubated in a laboratory condition with 15% moisture content. Phosphogypsum treatments were 2.5 and 5.0 g/kg soil and in the treatments of phosphogypsum and compost mixture 10 g of compost was added additionally. After the 30 days of incubation, an additional phosphogypsum and/or compost were added to the remaining soils at the same rates of the first treatments. pH, electrical conductivity, and available hazardous elements were measured periodically during the incubation. Field experiment was conducted in a plastic film house of mellon with four treatments of phosphogypsum and compost mixtures - 25+125, 50+125, 50+250 and 100+250 kg/165 $m^2$. pH, electrical conductivity, and hazardous elements in soil and total hazardous elements in leaf were measured. In the laboratory experiment, after 30 days of the first phosphogypsum application, soil pHs were lowered by 0.7-0.8 units. After the second treatment of phosphogypsum 0.2 units of additional acidification occurred. However, acidification was not observed in the soils treated with mixtures of phosphogypsum and compost. In the laboratory experiment, phosphogypsum treatments increased electrical conductivity very significantly. In field experiment, pH and electrical conductivity of soils treated with phosphogypsum were nearly the same as those of soil not treated with phosphogypsum. Since soil condition in the field study was an open system, the free acids and salts derived from phosphogypsum could be diffused down with water leaching through the soil profile and then any significant acidification or salt accumulation in the topsoil could not be observed. In both laboratory and field experiments, levels of available hazardous elements in soils treated with phosphogypsum were quite low and not different from the levels found in the control soil. Results obtained from this study suggest that application of phosphogypsum at appropriate rates on agricultural land appears of no concern in terms of acidity, salinity and hazardous element content of soil.

• Journal of Korean Vacuum Science & Technology
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• v.3 no.1
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• pp.79-84
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• 1999

the photolithographic patterning on an indium-tin oxide (ITO) glass and the electro-phoretic deposition were combined for preparing the screen of the full-color field emission display(FED). the patterns with a pixel of 400$\mu\textrm{m}$ on the ITO-glass were made by etching the ITO with well-prepared etchant consisting of HCL, H2O, and HNO3. Electrophoretic method was carried out in order to deposit each spherical red (R), green(G), and blue (B) phosphor on the patterned ITO-glass. The process parameters such as bias voltage, salt concentration, and deposition time were optimized to achieve clear boundaries. It was found that the etching process of ITO combined with electrophoretic method was cost-effective, provided distinct pattern, and even reduced process steps compared with conventional processes. The application of reverse bias to the dormant electrodes while depositing the phosphors on the stripe pattern was found to be very critical for preventing the cross-contamination of each phosphor in a pixel.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2015.11a
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• pp.256-257
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• 2015

마그네슘 합금은 낮은 비중, 높은 비강도, 주조성 및 절삭가공성, 치수안정성, 내흠집성이 우수한 특성을 지니고 있는 경량금속으로써 우수한 주조성과 상온강도, 연신율을 나타낸다. 최근에는 마그네슘 합금을 사용한 IT 기기의 케이스 및 자동차 내, 외장 부품 등의 제품이 다양하게 출시되어지며 금속 질감의 감성 기능까지 적용시킨 전자 기기 제품에 대한 수요가 급증하고 있는 추세이다. 하지만 마그네슘 합금의 낮은 부식 저항성은 마그네슘 합금을 적용시킨 제품에 큰 단점으로 작용되고 있으며 이를 해결하기 위한 연구가 활발히 진행 중이다. 본 연구에서는 플라즈마 전해산화법과 실리카 졸-겔 코팅법을 이용하여 마그네슘 합금의 내부식성을 향상시킴과 동시에 금속질감의 감성 기능을 구현하고자 하였다. 플라즈마 전해산화 공정으로 형성된 산화피막층과 $SiO_2$ 코팅으로 형성된 코팅층의 표면과 단면에 대해서는 FE-SEM(Field emission Scanning Electron Microscope)과 FE-TEM(Field emission Transmission Electron Microscope)으로써 확인하였고 전기화학적 특성 분석을 통한 동전위(Potentiodynamic polarization)와 EIS(Eletrochemical Impedance Spectroscopy) 그리고 Salt spray등을 분석하였다.

• Journal of the Korean GEO-environmental Society
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• v.20 no.4
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• pp.31-38
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• 2019

Field tests with carbon fiber heating wire (CFHW) embedded inside concrete slab were performed to present the alternative heating material capable of avoid the adverse effects of traditional de-freezing salt on the structures and environment. The CFHW was inserted into the concrete slab in the shape of 'ㄷ' to improve the heat superposition and the temperature on the surface was measured using iButton. The results showed that the temperature where the CFHW's were faced with each other increased to above zero after 12-hour at outdoor air temperature of $-6^{\circ}C$. Comparatively, the temperature slightly increased where the CFHW was embedded on one side because the heat was not superimposed. Hence, it can be said that the CFHW is a suitable heating material to prevent the concrete road from being frozen.

• Animal Bioscience
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• v.35 no.4
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• pp.631-637
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• 2022

Objective: Surface disinfection is important in the proper running of livestock farms. However, disinfection of farm equipment and facilities is difficult because they are made of different materials, besides having large surface areas and complex structures. 3-(trimethoxysilyl)-propyldimethyloctadecyl ammonium chloride (Si-QAC) is a quaternary ammonium salt-based disinfectant that attaches to various surfaces by forming covalent bonds and maintains its disinfecting capacity for a considerable time. Our aim was to evaluate the potential use of Si-QAC for disinfection of farm equipment and facilities. Methods: The short- and long-term antimicrobial and antiviral effects of Si-QAC were evaluated in both laboratory and farm settings using modified quantitative assessment method based on the standard operating procedures of the United States Environmental Protection Agency. Results: Si-QAC was highly effective in controlling the growth of the Newcastle disease virus and avian pathogenic Escherichia coli. Electron microscopy revealed that the mechanism underlying the disinfection activity of Si-QAC was associated with its ability to damage the outer membrane of the pathogen cells. In the field test, Si-QAC effectively reduced viral contamination of surfaces of equipment and space. Conclusion: Our results suggest that Si-QAC has great potential as an effective chemical for disinfecting farm equipment and facilities. This disinfectant could retain its disinfection ability longer than other commercial disinfectants and contribute to better farm biosecurity.

• The Plant Pathology Journal
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• v.22 no.3
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• pp.295-302
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• 2006

The present study addressed the efficacy of nanosized silica-silver for controlling plant pathogenic microorganisms. The nanosized silica-silver consisted of nano-silver combined with silica molecules and water soluble polymer, prepared by exposing a solution including silver salt, silicate and water soluble polymer to radioactive rays. The nanosized silica-silver showed antifungal activity against the tested phytopathogenic fungi at 3.0 ppm with varied degrees. In contrast, a number of beneficial bacteria or plant pathogenic bacteria were not significantly affected at 10 ppm level but completely inhibited by 100 ppm of nanosized silicasilver. Among the tested plant pathogenic fungi, the new product effectively controlled powdery mildews of pumpkin at 0.3 ppm in both field and greenhouse tests. The pathogens disappeared from the infected leaves 3 days after spray and the plants remained healthy thereafter. Our results suggested that the product developed in this study was effective in controlling various plant fungal diseases.

• Proceedings of the Korean Geotechical Society Conference
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• 1999.03a
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• pp.539-542
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• 1999

In this study, acrylate salt material of new chemical composition for injection grouting was prepared in the state of aqueous solution, and the chemical and physical properties of the material were investigated. The gelation time of the material was freely controllable through the control of added catalysts amount. As the viscosity of the material was very low (2∼3cps), its injection efficiency was expected to be very excellent. The variation of its viscosity plotted with the process of gelation revealed that the efficiency of its penetration into the ground soil was very excellent. The LD$\sub$50/ test on white mouse verified the toxicity of the material was very slight and substantially negligible. The grouting effect using the material was examined through field case histories.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2003.09a
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• pp.563-566
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• 2003

Quality measures play an important role in the field of image processing. Such measures are commonly used to assess the performance of different algorithms that are designed to perform a specific image processing task. In this paper we propose two novel measures for image quality assessment based on the notion of correlation between fuzzy sets. Two different definitions fur the correlation between fuzzy sets have been used. In order to calculate the proposed quality measures two approaches were evaluated, one with direct application of the measures to the image′s pixels and the other using the fuzzy set corresponding to the normalized histogram of the image. A comparative study of the proposed measures is performed by investigating their behavior using images with different types of distortions, such as impulsive "salt at pepper" noise, additive white Gaussian noise, multiplicative speckle noise, blurring, gamma distortion, and JPEG compression.