• Corrosion Science and Technology
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• v.11 no.1
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• pp.15-19
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• 2012

Both electrogalvanized and hot-dip galvanized steel sheets have been finally produced via organic-inorganic surface coating process on the zinc surface to enhance corrosion resistance and afford additional functional properties. Recently, POSCO has been developed a variety of chromate-free coated steels that are widely used in household, construction and automotive applications. New organic-inorganic hybrid coating solutions as chromate alternatives are comprised of surface modified silicate with silane coupling agent and inorganic corrosion inhibitors as an aqueous formulation. In this paper we have prepared new type of hybrid coatings and evaluated quality performances such as corrosion resistance, spot weldability, thermal tolerance, and paint adhesion property etc. The electrogalvanized steels with these coating solutions exhibit good anti-corrosion property compared to those of chromate coated steels. Detailed components composition of coating solutions and experimental results suggest that strong binding between organic-inorganic hybrid coating layer and zinc surface plays a key role in the advanced quality performances.

• Journal of Korea Society of Digital Industry and Information Management
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• v.10 no.1
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• pp.89-97
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• 2014

Recently, spread of Smartphones caused activation of mobile services, because of that Big Data such as clouding service able to proceed with large amount of data which are hard to collect, save, search and analyze. Many companies collected variety of private and personal information without users' agreement for their business strategy and marketing. This situation raised social issues. As companies use Big Data, numbers of damage cases are growing. In this Thesis, when Big Data process, methods of analyze and research of data are very important. This thesis will suggest that choices of security levels and algorithms are important for security of private informations. To use Big Data, it has to encrypt the personal data to emphasize the importance of security level and selection of algorithm. Thesis will also suggest that research of utilization of Big Data and protection of private informations and making guidelines for users are require for security of private information and activation of Big Data industries.

• Proceedings of the IEEK Conference
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• 2002.06d
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• pp.97-100
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• 2002

In this paper, we propose a watermarking technique that embeds a digital watermark into digital images for the proof of owner or copyright protection. Proposed algorithm is based on discrete wavelet transform. Zerotree structure defined by Shapiro's embedded zerotree wavelet(EZW) algorithm is used. In the proposed algorithm, a digital watermark is embedded on only significant wavelet coefficients chosen by QSWT for the robustness of the algorithm. In other words, only the values of significant wavelet coefficients are modified in accordance with the given watermark pattern. We use the relationship among neighboring coefficients when modifying chosen coefficients to keep good image quality. Visual recognizable patterns such as binary images are used as a watermark. The experimental results show that the proposed algorithm has robustness under a variety of attacks such as JPEG compression, sharpening and blurring and also show that it has a better performance in PSNR comparing with other algorithms.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.2
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• pp.358-370
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• 1994

Plant cell walls consist of a variety of chemical constituents such as cellulose, humicelluloses, pertins, lignin, glycoproteins, etc. These components are strongly linked through hydrogen , covalent, ionic and hydrophobic bondings, which thus confers the self-protection capability on plants. Some processing by-products (hulls, brans, pomaces) of cereal, fruits and vegetables are very limited in further utilization due to their compact structural rigidity. In view of the fact that the plant cell walls are essentially composed of dietary fiber components , solubilization of the strong intermolecular linkage s can contribute to increasing the soluble dietary fiber content and thus diversifying the functional and physiological role of plant cell walls as dietary fiber sources. This article reviews the chemical constituents of cereals, fruits & vegetables and brown seaweeds with reference to their intermoleuclar linkages. An particular emphasis will be placed on the solubilizing phenomena of rigid plant cell walls by extrusion and the resulting change of functional properties. It is suggested that underutilized food resources, typically exemplified by various food processing by-products and surplus seaweeds, can be successfully modified toward improved functional performance by extrusion.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.49 no.4
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• pp.143-151
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• 2000

Electric power distribution feeders are susceptible to faults caused by a variety of situations such as adverse weather conditions, tree contacts, equipment failure, accidents, etc. Distribution circuit faults result in a number of problems related to the reliability of service and customer power quality. In the distribution line, the permanent interruption of customer service resulting from a blown fuse or a recloser lockout was the only factor which was used to determine service reliability. On underground distribution line, the serving of cables by earth-moving equipment is a prevalent cause of faults and the most cable faults quickly develop into bolted current. we introduce th multi-circuit breaker coordination methods in the Underground Distribution Line.

• Proceedings of the KIEE Conference
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• 1998.07c
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• pp.1244-1246
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• 1998

This paper present a variety fault problem brought out with the multifunctional Battery Energy Storage System [MBESS] expected to be practical in the short future interconnected to power distribution system. Multifunctional BESS model and interconnection model to power system is simply configured, the problems of protection coordination and operation is studied. A line fault in the power distribution system are discussed such as line to ground and three phase fault in order to show the impact on power utilities, demand-side and BESS-side. In order to simulate a variable transient phenomenon due to 2 the BESS interconnection operation to power distribution system, in this paper, PSCAD/EMTDC simulation tools is used.

• Journal of Ginseng Research
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• v.42 no.3
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• pp.264-269
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• 2018

Panax ginseng, also called Asian or Korean ginseng, has long been traditionally used in Korea and China to treat various diseases. The major active ingredients of P. ginseng are ginsenosides, which have been shown to have a variety of therapeutic effects, including antioxidation, anti-inflammatory, vasorelaxation, antiallergic, antidiabetic, and anticancer. To date, approximately 40 ginsenoside components have been reported. Current research is concentrating on using a single ginseng compound, one of the ginsenosides, instead of the total ginseng compounds, to determine the mechanisms of ginseng and ginsenosides. Recent in vitro and in vivo results show that ginseng has beneficial effects on cardiac and vascular diseases through efficacy, including antioxidation, control of vasomotor function, modulation of ion channels and signal transduction, improvement of lipid profiles, adjustment of blood pressure, improvement in cardiac function, and reduction in platelet adhesion. This review aims to provide valuable information on the traditional uses of ginseng and ginsenosides, their therapeutic applications in animal models and humans, and the pharmacological action of ginseng and ginsenosides.

• Proceedings of the Korean Society of Life Science Conference
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• 2007.10a
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• pp.26.2-26.2
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• 2007

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• Journal of Power Electronics
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• v.10 no.2
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• pp.125-131
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• 2010

Switched-resonator converters are a new family of soft switching DC-DC converters where the energy is transferred via a resonator. This paper introduces some isolated topologies of this family. The achieved advantages include, load independent soft-switching, self short-circuit protection, and optimization capability due to topology variety. Compared to conventional series-resonant converters, outstanding advantages such as a smaller fewer number of switches and diodes, a smaller transformer, and lower current stresses are achieved. A general synthesis scheme, functional topologies, and essential relations are included. Experimental results from a laboratory prototype confirm the presented theoretical analysis.

• Journal of the Korean Professional Engineers Association
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• v.45 no.6
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• pp.28-32
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• 2012

Namhae chemical is one of the largest fertilizer manufacturing company in Korea which company has operating 4 unit agitator gear boxes and producing variety kinds of fertilizer production. The gearbox operating temperature of agitator is approximated in $55^{\circ}C{\sim}90^{\circ}C$ and required to keep operating continuous without stopping. The system required high performance oil and longer oil drain interval as limited workforce in maintenance team. It was lubricated by mineral gear oil of ISO VG 320 and also need to change to new oil frequently. Namhae Chemical would expect to keep stable operating condition without shut down and consider, lower cost of operation and equipment protection.