• Nuclear Engineering and Technology
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• v.27 no.4
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• pp.571-581
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• 1995

The generation, verification and validation of Emergency Procedures for Nuclear Power Plant is a difficult and complex process. Atomic Energy Control Board(AECB) requires that emergency procedure and plan be produced before obtaining the Operating License, that is, detailed plans and procedures to handle emergency situations for both on-site actions and off-site actions be developed. In this report Emergency Operating Procedures Standard for Canadian Nuclear Utilities which makes reference to U. S. practices and the current direction of emergency procedures for CAN-DU reactors are reviewed and compared based on scope(events covered), methodology (event-oriented or symptom-oriented or hybrid) and format(method of presentation) preponderantly, and an attempt is made to integrate these procedures and as a result the recommended strategy for Wolsong unit 2, 3, & 4 is presented as event-specific procedures, generic procedures(when event is not diagnosed) and whose format is combination of logic diagram and text.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.172-172
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• 2011

Anaerobic digestion(AD) has successfully been used for many applications that have conclusively demonstrated its ability to recycle biogenic wastes. AD has been successfully applied in industrial waste water treatment, stabilsation of sewage sludge, landfill management and recycling of biowaste and agricultural wastes as manure, energy crops. During AD, i.e. organic materials are decomposed by anaerobic forming bacteria and fina1ly converted to excellent fertilizer and biogas which is primarily composed of methane(CH4) and carbon dioxide(CO2) with smaller amounts of hydrogen sulfide(H2S) and ammonia(NH3), trace gases such as hydrogen(H2), nitrogen(N2), carbon monoxide(CO), oxygen(O2) and contain dust particles and siloxanes. The production and utilisation of biogas has several environmental advantages such as i)a renewable energy source, ii)reduction the release of methane to the atomsphere, iii)use as a substitute for fossil fuels. In utilisation of biogas, most of biogas produced from small scale plant e.g. farm-scale AD plant are used to provide as energy source for cooking and lighting, in most of the industrialised countries for energy recovery, environmental and safety reasons are used in combined heat and power(CHP) engines or as a supplement to natural. In particular, biogas to use as vehicle fuel or for grid injection there different biogas treatment steps are necessary, it is important to have a high energy content in biogas with biogas purification and upgrading. The energy content of biogas is in direct proportion to the methane content and by removing trace gases and carbon dioxide in the purification and upgrading process the energy content of biogas in increased. The process of purification and upgrading biogas generates new possibilities for its use since it can then replace natural gas, which is used extensively in many countries, However, those technologies add to the costs of biogas production. It is important to have an optimized purification and upgrading process in terms of low energy consumption and high efficiency giving high methane content in the upgraded gas. A number of technologies for purification and upgrading of biogas have been developed to use as a vehicle fuel or grid injection during the passed twenty years, and several technologies exist today and they are continually being improved. The biomethane which is produced from the purification and the upgrading process of biogas has gained increased attention due to rising oil and natural gas prices and increasing targets for renewable fuel quotes in many countries. New plants are continually being built and the number of biomethane plants was around 100 in 2009.

• Applied Chemistry for Engineering
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• v.28 no.6
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• pp.607-618
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• 2017

Harmful air pollutants are exhausted from the various industrial facilities including the coal-fired thermal power plants and these substances affects on the human health as well as the nature environment. In particular, nitrogen oxides ($NO_x$) and sulfur dioxide ($SO_2$) are known to be causative substances to form fine particles ($PM_{2.5}$), which are also deleterious to human health. The integrated system composed of selective catalytic reduction (SCR) and wet flue gas desulfurization (WFGD) have been widely applied in order to control $NO_x$ and $SO_2$ emissions, resulting in high investment and operational costs, maintenance problems, and technical limitations. Recently, new technologies for the simultaneous removal of $NO_x$ and $SO_2$ from the flue gas, such as absorption, advanced oxidation processes (AOPs), non-thermal plasma (NTP), and electron beam (EB), are investigated in order to replace current integrated systems. The proposed technologies are based on the oxidation of $NO_x$ and $SO_2$ to $HNO_3$ and $H_2SO_4$ by using strong aqueous oxidants or oxidative radicals, the absorption of $HNO_3$ and $H_2SO_4$ into water at the gas-liquid interface, and the neutralization with additive reagents. In this paper, we summarize the technical improvements of each simultaneous abatement processes and the future prospect of technologies for demonstrating large-scaled applications.

• Journal of Energy Engineering
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• v.25 no.4
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• pp.152-158
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• 2016

Nitrogen oxide is generated by the chemical reaction of oxygen and nitrogen in higher temperature environment of combustion facilities. The NOx reduction equipment is generally used in the power plant or incineration plant and it causes enormous cost for the construction and maintenance. The flue gas recirculation method is commonly adopted for the reduction of NOx formation in the combustion facilities. In the present study, the computational fluid dynamic analysis was accomplished to elucidated the cold flow characteristics in the flue gas recirculation burner with coanda nozzles in the flue gas recirculation pipe. The inlet and outlet of flue gas recirculation pipes are directed toward the tangential direction of circular burner not toward the center of burner. The swirling flow is formed in the burner and it causes the reverse flow in the burner. The ratio of flue gas recirculation flow rate with the air flow rate was about 2.5 for the case with the coanda nozzle gap, 0.5mm and it was 1.5 for the case with the gap, 1.0mm. With the same coanda nozzle gap, the flue gas recirculation flow rate ratio had a little increase when the air flow rate changes from 1.1 to 2.2 times of ideal air flow rate.

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2002.04b
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• pp.33-40
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• 2002

We, Tong Yang Moolsan Co. Ltd. (TYM) set up the mass-production system for virus-free seed garlic via tissue culture technique. TYM's tissue culture technique is called as 'Multiple shoot propagation technique'. This technique can lead mass propagation of genetically homogeneous seed garlic in a short period because of its highly proliferation ,ate of in vitro shoots $(15^{10}/year)$. TYM researchers applied the technique to some selected garlic cultivars with superior characteristics and carried out Held test of productivity in the inside and outside of the country for several years. According to the yearly results of Held test with virus-free seed garlic, we ascertained that virus-free seed garlic can produce the highly yield increase (max. above 50%) and also can enhance the product quality. Consequently, we estimated that TYM's seed garlic will contribute to farmers with increase of income and can elevate the national position of garlic market in the world for its competitive power of technical and production cost.

• Journal of Plant Biotechnology
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• v.29 no.3
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• pp.171-177
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• 2002

We, Tong Yang Moolsan Co. Ltd. (TYM) set up the mass-production system for virus-free seed garlic via tissue culture technique. TYM's tissue culture technique is called as 'Multiple shoot propagation technique' This technique can lead mass propagation of genetically homogeneous seed garlic in a short period because of its highly proliferation rate of in vitro shoots (15/sup 10//year). TYM researchers applied the technique to some selected garlic cultivars with superior characteristics and carried out field test of productivity in the inside and outside of the country for several years. According to the yearly results of field test with virus-free seed garlic, we ascertained that virus-free seed garlic can produce the highly yield increase (max. above 50%) and also can enhance the product quality. Consequently, we estimated that TYM's seed garlic will contribute to farmers with increase of income and can elevate the national position of garlic market in the world for its competitive power of technical and production cost.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.5
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• pp.944-958
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• 2011

Soil hydraulic properties such as hydraulic conductivity or water retention which are costly to measure can be indirectly generated by soil pedotransfer function (PTF) using easily obtainable soil data. The field soil structure description which is routinely recorded could also be used in PTF as an input to reduce the uncertainty. The purposes of this study were to use qualitative morphological soil structure descriptions and soil structural index into PTF and to evaluate their contribution in the prediction of soil hydraulic properties. We transformed categorical morphological descriptions of soil structure into quantitative values using categorical principal component analysis (CATPCA). This approach was tested with a large data set from the US National Pedon Characterization database with the aid of a categorical regression tree analysis. Six different PTFs were used to predict the saturated hydraulic conductivity and those results were averaged to quantify the uncertainty. Quantified morphological description was successively used in multiple linear regression approach to predict the averaged ensemble saturated conductivity. The selected stepwise regression model with only the transformed morphological variables and structural index as predictors predicted the $K_{sat}$ with $r^2$ = 0.48 (p = 0.018), indicating the feasibility of CATPCA approach. In a regression tree analysis, soil structure index and soil texture turned out to be important factors in the prediction of the hydraulic properties. Among structural descriptions size class turned out to be an important grouping parameter in the regression tree. Bulk density, clay content, W33 and structural index explained clusters selected by a two step clustering technique, implying the morphologically described soil structural features are closely related to soil physical as well as hydraulic properties. Although this study provided relatively new method which related soil structure description to soil structure index, the same approach should be tested using a datasets containing the actual measurement of hydraulic properties. More insight on the predictive power of soil structure index to estimate hydraulic properties would be achieved by considering measured the saturated hydraulic conductivity and the soil water retention.

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.4
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• pp.61-68
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• 2019

As the pollution of water resources deteriorates due to industrialization and urbanization, it is difficult to supply clean water through a water treatment method using chlorine. Therefore, the introduction of advanced water treatment facilities using ozone is on the increase. However, epoxy which is used as waterproofing and anticorrosives and stainless steel used in conventional waterproofing and anti-corrosive methods have deteriorated because of the strong oxidizing power of ozone, causing problems such as leaking. Moreover, it even causes the durability degradation of a concrete. Therefore, in this study, metal spraying system was used as the means of constructing a metal panel with excellent ozone resistance and chemical resistance which is an easier method than an existing construction method. Ozone resistance was evaluated in accordance with the type of metal sprayed coatings to develop a finishing method which can prevent the concrete structure of water treatment facilities from deterioration. Furthermore, electrochemical stability in actual sewage treatment plant environment was evaluated. Experimental results showed that Ti has superior ozone resistance after spraying and the electrochemical stability in the sewage treatment plant environment showed that Ti has the highest polarization resistance of $403.83k{\cdot}{\Omega}{\cdot}cm^2$, which ensures high levels of durability.

• Journal of Life Science
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• v.29 no.8
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• pp.846-853
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• 2019

Phytochemical compounds of Ligusticum striatum Makino are used as traditional medicinal herbs in Asia. These compounds are reported to have pain relief and antioxidant activities in gynecological and brain diseases. In this study, we investigated the antioxidant effects of Ligusticum fermented ethanol extract from Lactobacillus plantarum BHN-LAB 129 isolated from Kimchi, a Korean traditional food. The total polyphenol and total flavonoid contents increased by about 116.2% and 281.0% respectively, in the fermented Ligusticum extract as compared with those in the nonfermented Ligusticum ethanol extract. Superoxide dismutase-like (SOD), DPPH radical scavenging, ABTS radical scavenging, and reducing power activities increased by around 139.9%, 199.6%, 301.0%, and 137.1%, respectively, in the fermented Ligusticum ethanol extract as compared with these parameters in the nonfermented Ligusticum ethanol extract, respectively. In conclusion, the fermented Ligusticum ethanol extract with L. plantarum BHN-LAB 129 was effective in increasing the antioxidant effects. The bioconversion process in this study points to the potential of using Ligusticum to produce phytochemical-enriched natural antioxidant agents with high added value. The findings may prove useful in the development of improved foods and cosmetic materials.

• Journal of the Korean Society of Propulsion Engineers
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• v.24 no.5
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• pp.43-55
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• 2020

The effect of cutted pin in front of pin-fin array was analyzed for increasing the cooling performance of gas turbine blade. The numerical simulations were conducted to figure out the flow and thermal characteristics. The base case which is staggered pin-fin array, cut pin case 1 which has X₂/D_p=1.25 cut pin and cut pin case 2 which has X₃/D_p=1.75 cut pin were compared. The results showed that cut pin increases the strength of the horseshoe vortex which occurred at the leading edge of pin-fin array. Furthermore, the wake effect is reduced at the trailing edge of pin-fin array. As a result, the heat transfer distribution on the endwall increases. However, the friction factor increases owing to the installation of cut pin, but the thermal performance factor is increased maximum 23.8% in cut pin case 2. Therefore, installation of cut pin will be helpful for increasing the cooling performance of pin-fin array of gas turbine blade.