• KEPCO Journal on Electric Power and Energy
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• v.8 no.1
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• pp.37-41
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• 2022

Because sulfur hexafluoride(SF₆) is classified as one of the six major greenhouse gases, SF₆ handling in power plant such as recovery, purification, and reuse is considered to be important. KEPCO has focused to develop the advanced recovery and purification technology of SF₆ reuse. SF₆ analysis includes the on-site analyses and on-line analyzer; i.e., (1) on-site analysis has an error rate of ±0.5% and (2) on-line analysis has an error rate of ±0.1%, which is possible to adjust operating conditions and to make the work more conveniently by analyzing SF₆ concentration before and after purification step. This paper presents an online analysis method in the SF₆ purification and reuse system. In addition, the analysis results and quality guarantees for each section of the analysis system were presented.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.33 no.3
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• pp.449-458
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• 2023

Artificial Intelligence is providing convenience in various fields using big data and deep learning technologies. However, deep learning technology is highly vulnerable to adversarial examples, which can cause misclassification of classification models. This study proposes a method to detect and purification various adversarial attacks using StarGAN. The proposed method trains a StarGAN model with added Categorical Entropy loss using adversarial examples generated by various attack methods to enable the Discriminator to detect adversarial examples and the Generator to purification them. Experimental results using the CIFAR-10 dataset showed an average detection performance of approximately 68.77%, an average purification performance of approximately 72.20%, and an average defense performance of approximately 93.11% derived from restoration and detection performance.

• Journal of the korean Society of Automotive Engineers
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• v.3 no.1
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• pp.46-53
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• 1981

This paper describes emission control of hydrocarbon and carbon-monoxide due to oxidizing catalyst. The experiment was performed on a precious metal pelleted catalyst(Pt). The factors of the efficiency for purification due to oxidizing catalyst are space velocity, temperature, composition of exhaust gas and supplementary air. The experiment was carried out to control the factors of efficiency for purification. The results of experimental study show that temperature of catalytic converter, supplementary air and space velocity affected the efficiency for purification of hydrocarbon and carbon monoxide.

• Journal of Environmental Science International
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• v.7 no.6
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• pp.853-857
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• 1998

Purification of the isocitrate lyase extracted from Microbacterium laevaniformans was investigated. The isocitrate lyase was purified 43.6 folds by the following continuous treatment with ammonium sulfate fraction, DEAE-cellulose, DEAE-sephacel and Sephadex G-200 chromatography. The purified isocitrate lyase was showed to be a single protein band by polyacrylamide gel electrophoresis. The molecular weight of the purified isocitrate lyase was estimated 54,000 Da by the SDS-polyacrylamide gel electrophoresis. The Km and Vmax values for isocitrate were estimated to be 0.83mM and 0.33units/ml, respectively. Activity of isocitrate lyase was inhibited by cystein-HCl and glutathione.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 1999.10a
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• pp.53-56
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• 1999

The concerned party of purification liability in a soil pollution is an owner or occupant of a contaminated site. But when we don't appoint the polluter or he can't do a cleanup, municipal put in effect the purification. In such a case, another parties who are related to the contamination ought to the liability. The province of responsible parties, therefore, is required to extend to an owner or operator of a facility, a carrier and lender

• Bulletin of the Korean Chemical Society
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• v.30 no.1
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• pp.124-128
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• 2009

In this study, the effect of multi-step purification or functionalization on physicochemical properties of multi-walled carbon nanotubes (MWNTs)/epoxy (EP) nanocomposites was investigated. The nanocomposites containing multi-step purified MWNTs showed a stronger influence on $T_g$ and increased in mechanical properties in comparison to nanocomposites containing the same amount of only purified MWNTs. Consequently, the multi-step purification of MWNTs led to an improvement of thermomechanical properties of nanocomposites, resulting from improving the intermolecular interaction of MWNTs in epoxy matrix resins.

• Bulletin of the Korean Chemical Society
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• v.18 no.6
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• pp.648-653
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• 1997

Acetolactate synthase was purified from Escherichia coli MF2000/pTATX containing Arabidopsis thaliana acetolactate synthase gene. Purification steps included DEAE cellulose ion exchange column chromatography, phenyl sepharose hydrophobic column chromatography, hydroxylapatite affinity column chromatography, and Mono-Q HPLC. Molecular weight was estimated to be ∼65 KDa and purification fold was 109 times. The enzyme showed a pH optimum of 7 and the $K_M$ value was 5.9 mM. The purified enzyme was not inhibited by any of the end products, valine, leucine, and isoleucine.

• Journal of Ginseng Research
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• v.22 no.4
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• pp.284-288
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• 1998

This study was carried out to establish a new efficient method for isolation and purification of ginsenosides. Silica gel column chromatography, having been used for the isolation of ginsenosides, is advantageous to obtain a large amount of ginsenosides. However, it has a disadvantage to isolate ginsenosides to their highest purity. In addition, normal-or reverse-phase HPLC method thus far reported is confined to quantitative analysis. Especially, it has not been possible to isolate racemic 20(S)- and 20(R)-ginsenoside Rg2. In this experiment, isolation and purification of ginsenosides were accomplished by Diaion HP-20 adsorption chromatography, silica gel column chromatography, recrystalization and Prep. HPLC with or without Prep. TLC. From this study, we could establish a new efficient method for isolation and purification of 9 major and/or minor ginsenosides.

• Journal of Environmental Impact Assessment
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• v.18 no.2
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• pp.79-87
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• 2009

This study was performed for the application of porous concrete blocks and aquatic plants for the water purification in small urban stream. This study investigated the ability of water purification according to various environments, algae and aquatic plants. When the porous concrete was used as contact media, the average removal efficiencies of SS, BOD and COD were 85~95%, 50~60% and 65~75%, respectively. Also, when the porous concrete and aquatic plants was used the average removal efficiency of SS, BOD and COD were 90~95%, 60~70% and 70~80%, respectively. As the results, average removal efficiency of total nitrogen, at the condition of the porous concrete and aquatic plants, was about 40-50%, then, that of total phosphorus was about 60-70%.

• Bulletin of the Korean Chemical Society
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• v.35 no.9
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• pp.2665-2668
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• 2014

Aptamers are oligonucleotides or peptide molecules that are able to bind to their specific target molecules with high affinity via molecular recognition. In this study, we present development of aptamer-based precipitation assays (or simply aptamoprecipitation) for His-tagged proteins and thrombin to compare their purification efficiency with other conventional affinity precipitation methods. A crosslinking method was employed to immobilize thiol-functionalized aptamers onto the surface of polystyrene resins, enabling them to specifically bind to His-tag and to thrombin, respectively. The resulting aptamer-functionalized resins were successfully applied via a one-step experiment to purification of His-tagged proteins from complex E. coli and to thrombin extraction, exhibiting superior or at least comparable purification results to the conventional immobilized metal affinity precipitation or immunoprecipitation.