• Journal of the Korean institute of surface engineering
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• v.40 no.5
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• pp.219-224
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• 2007

The corrosion characteristics of Fe-18Cr-10Ni steels were studied between $600^{\circ}C$ and $1000^{\circ}C$ in Ar+(0.2, 1)%$SG_2$ gas for up to 300 hr in order to employ Fe-18Cr-10Ni steels in the coal-fired power plants. The corrosion resistance of Fe-18Cr-10Ni steels was good due mainly to the high amount of Cr, which formed $Cr_2O_3$ from the initial corrosion stage. Fe in the steels corroded to mainly $Fe_2O_3$ and $Fe_3O_4$. Ni was not susceptible to corrosion under the current corrosion condition. Relatively thin, single-layered scales formed.

• Journal of the Korean Society of Safety
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• v.32 no.3
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• pp.160-171
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• 2017

US national research laboratories developed the first Vital Area Identification (VAI) method for the physical protection of nuclear power plants that is based on Event Tree Analysis (ETA) and Fault Tree Analysis (FTA) techniques in 1970s. Then, Korea Atomic Energy Research Institute proposed advanced VAI method that takes advantage of fire and flooding Probabilistic Safety Assessment (PSA) results. In this study, in order to minimize the burden and difficulty of VAI, (1) a set of streamlined VAI rules were developed, and (2) this set of rules was applied to PSA fault tree and event tree at the initial stage of VAI process. This new rule-based VAI method is explained, and its efficiency and correctness are demonstrated throughout this paper. This new rule-based VAI method drastically reduces problem size by (1) performing PSA event tree simplification by applying VAI rules to the PSA event tree, (2) calculating preliminary prevention sets with event tree headings, (3) converting the shortest preliminary prevention set into a sabotage fault tree, and (4) performing usual VAI procedure. Since this new rule-based VAI method drastically reduces VAI problem size, it provides very quick and economical VAI procedure. In spite of an extremely reduced sabotage fault tree, this method generates identical vital areas to those by traditional VAI method. It is strongly recommended that this new rule-based VAI method be applied to the physical protection of nuclear power plants and other complex safety-critical systems such as chemical and military systems.

• Korean Chemical Engineering Research
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• v.52 no.4
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• pp.503-515
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• 2014

A lot of existing wastewater treatment plants (WWTPs) are rebuilt or retrofitted for advanced wastewater treatment processes to cope with reinforced effluent criteria of nitrogen and phosphorous. Moreover, how to treat the wasted sludge from WWTPs has been also issued since the discharge of the wasted sludge into ocean is impossible from 2011 due to the London Convention 97 protocol. These trend changes of WWTPs get a motivation to assess environmental and economic impacts from the construction stage to the waste stage in WWTPs. Therefore, this study focuses on evaluation of environmental and economic impacts of the advanced wastewater treatment processes and waste sludge treatment process by using life cycle assessment. Four advanced wastewater treatment processes of Anaerobic/Anoxic/Oxic ($A_2O$), 5 stages-Bamard Denitrification Phosphate (Bardenpho), Virginia Initiative Plant (VIP), and Modified University of Cape Town (MUCT) are chosen to compare the conventional activated sludge (CAS) and three waste sludge treatment methods of land fill, incineration, and composting are used. To evaluate environmental and economic impacts of each advanced wastewater treatment processes, life cycle assessment (LCA) and life cycle cost (LCC) are conducted based on International organization for standardization (ISO) guidelines. The results clearly represent that the $A_2O$ process with composting shows 52% reduction in the environmental impact than the CAS process with landfill. On the other hand, the MUCT process with composting is able to save 62% of the life cycle cost comparing with the CAS process with landfill. This result suggested the qualitative and quantitative criteria for evaluating eco-environmental and economic technologies of advanced treatment processes and also sludge treatment method, where their main influence factors on environmental and economic impacts are analyzed, respectively. The proposed method could be useful for selecting the most efficient and eco-friendly wastewater treatment process and sludge treatment method when retrofitting the existing WWTPs to advanced treatments.

• Horticultural Science & Technology
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• v.34 no.6
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• pp.924-939
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• 2016

The great economic losses caused by Cucumber mosaic virus (CMV) infection of peppers has led to the development of genetically modified (GM) CMV-resistant peppers. We developed virus-resistant pepper plants using Agrobacterium tumefaciens -mediated transformation. The expressed recombinant protein was purified using nickel-nitrilotriacetic acid resin and immunoaffinity chromatography, and purity was assessed by sodium dodecyl sulfate polyacrylamide gel electrophoresis. Immunoblot analysis revealed the purified CMV coat protein (CMV-CP) had a molecular mass of 25 kDa. After in-gel digestion and desalting, the internal peptide fragments of CMV-CP were sequenced by matrix-assisted laser desorption/ionization-time of flight. Most GM pepper and Escherichia coli BL21 internal peptides had identical peptide sequences and contained 137 of 183 whole peptides in CMV-CP. A quantitative enzyme-linked immunosorbent assay was performed to detect CMV-resistant GM peppers. We also provide basic information about the expressed protein in GM peppers for further safety assessment. The contents of soluble protein and CMV-CP were measured in GM and control peppers cultivated in three different areas of Korea. Statistical significance in terms of cultivation areas, harvest times, generations, and plant tissue origin were determined based on a P value of 0.05. The highest amount of CMV-CP was detected at the seedling stage from plant grown in each region. T3 and T5 showed significantly different levels of CMV-CP from T4 in leaves in the whorl stage. No statistical differences were observed among GM peppers at different stages of maturity in any cultivation area. The results from this study contribute to the safety evaluation of newly designed CMV-resistant GM peppers and provide a standard against which to compare other virus-resistant GM peppers.

• Korean Journal of Organic Agriculture
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• v.18 no.1
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• pp.93-104
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• 2010

This study was conducted screening of the population densities of fungal pathogens and insect and observed the disease symptoms on the organic sweet corn seed producing field from 2008 to 2009. The dissemination spores, Alternaria sp., Cladosporium sp., Helminthosporium sp., Pyricularia sp., Collectotrichum sp., and Bipolaris sp., were detected and the three fungal spores from the front were observed for whole growth stage. Seed and seedling diseases were shown as the rotted seed and damping-off seedling caused by Penicillium sp. and Rhizoctonia sp.. The larva of Black cutworm cut down the root crown of seedlings. The damaged plants were ranged from 14% to 16%. On the Oriental corn borer, the population densities and the percentage of damaged plants were showed a low difference between two sweet corn varieties. The population densities of Oriental corn borer were scored as from 3.5 to 20.5 in 2008 and from 0.5 to 6 in 2009. Also the percentage of damaged plants were significantly increased until harvesting stage and was recorded from 7.5% to 21% in 2008 and from 1% to 46% in 2009. On the Corn leaf blight, the percentage of diseased plant were scored from 7% to 34% in 2008. The first occurrence of date was after June 18, and the percentage of diseased plant was continuously increased after August 21 and the values of diseased plants was ranged from 56% to 69% in 2009. On common smut, the percentage of diseased plant was recorded from 5% to 15% in 2008, and the first occurrence date were delayed as 17 days (July 17) and were showed less than 8% of diseased plants in 2009. Corn Southern Leaf spot was scored as average 11% at early stage and showed high score as 62% at September 19 in 2008. In 2009, the first occurrence date were advanced about 20 days (after June 8), and continuously increased up to 86% in 2009.

• Horticultural Science & Technology
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• v.19 no.4
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• pp.560-563
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• 2001

To determine the minimum number of short day (SD) required for flower initiation and development of chrysanthemum, plants were exposed to SD and long day (LD) conditions. Floral development was significantly different between continuous exposure of 16 hour long day (LD) condition and 2 or 4 SD prior to LD in chrysan-themum cvs. Envy and Lady Time, respectively. As more SD exposure was given, final leaf number was decreased and floral stage was advanced, suggesting a facultative response to photoperiodic cycles. Therefore, only 2-4 days of SD were enough to induce flower initiation. After 6 weeks of SD condition, the plants continued anthesis regardless of subsequent photoperiods. The long day leaf number (LDLN) varied between cultivars as 38.0 and 45.4 in Envy and Lady Time, respectively.

• Journal of the Korean Society of Tobacco Science
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• v.11 no.2
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• pp.149-155
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• 1989

This study was conducted to obtain the breeding information for the leaf breakdown, and correlation coefficients between leaf breakdown and some agronomic characters in flue-cured tobacco at Taegu Experiment Station, Korea Ginseng & Tobacco Research Institute. NC 95 and NC 2326 were used as parents. The bulk method procedure was used from the F2 to the F4 generations, 54 plants were selected among F4, and 11 lines were selected among 54 F5 which based on high resistance to bacterial wilt compared with NC2326. The entries were composed of parents and 11 F6 advanced lines, and designed in randomized block with 3 replications. Plant seedlings were transplanted in 16 April. The number of breakdown leaf were investigated at flowering stage, 18 June. There were significant difference between NC 95 and NC 2326 for the number of breakdown leaf, number and weight of ground suckers, days to flower, yield and resistance to bacterial wilt, and similar results were appeared among lines. Estimated heritability in the broad-sense ranged from 59.3% to 87.4% for all characters. Most of genetic correlations were higher than phenotypic coefficients between characters. Number of breakdown leaf was positively correlated with days to flower, the number and weight of ground suckers, while it was negative to yield. One line among 11 had few breakdown leaf, low producted ground suckers and high resistance to bacterial wilt. Above results suggest that the number and weight of ground suckers can be use as a selection criterion for leaf breakdown even under the condition without leaf breakdown.

• Journal of the Korean Society of Tobacco Science
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• v.15 no.2
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• pp.152-160
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• 1993

Using a flue- cured tobacco variety, KF 109, effect of growth regulators(fatty alcohol and C- MH) on the change of protein, DNA, and RNA were investigated. Generally, inhibition of DNA synthesis was observed soon after become notably reduced when checked on 14 days after the treatment. Fatty alcohol treatment appeared to alleviate the inhibition of DNA synthesis caused by the C - MH treatment. It was also observed that in the tips DNA content increased slightly at the early stage after the C - MH treatment but evident reduction of it was resulted from 7th day after the treatment. RNA content in cutters and tips was increased initially but variable transcription inhibitory activities - not so obvious as was observed in DNA synthesis - according to leaf positions were shown thereafter. Ripening of leaves probably due to senescence was advanced by the treatment of the growth regulators. DNA content in root was relatively higher in plants treated with the growth regulators while it was clearly decreased in stalk, However, RNA contents in tissue of stalk and root was not different with that of foliage. Increase of protein content in foliage as well as in stalk was evident 14 days after dual treatment of fatty alcohol and C - MH.

• Journal of Korean Society for Atmospheric Environment
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• v.29 no.5
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• pp.536-544
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• 2013

Even a small amount of hazardous air pollutants could have a harmful influence upon human beings, animals and plants. Hazardous air pollutants have the properties of toxicity, canceration and organism accumulation. They include heavy metals, volatile organic compounds, polycyclic aromatic hydrocarbons, dioxin, etc. The Clean Air Conservation Act has defined specific hazardous air pollutants and designated 35 pollutants, distinguishing them from common air pollutants for special control. This study investigates the history of the controls of specific hazardous air pollutants with reference to some relevant laws and regulations in Korea. It investigates the regulations at the permission stage, such as the restrictions on installation of emission facilities, the permission and reporting of installation of emission facilities, and the regulations at the operation stage, such as maintaining permissible emission levels, installation of measuring devices, dues for emission, self-measurement and securing environmental engineers. The current regulatory management is not so satisfactory in regards to the serious effects of specific hazardous air pollutants upon the human body. An advanced new concept, like the maximum available control technology in US, the facilities management standards, which will soon take effect, will be able to lessen the emissions of fugitive hazardous air pollutants. In addition, this study discusses some possible stricter controls on the emission facilities of specific hazardous air pollutants and proposes some measures to maintain and supplement the current systems.

• Korean journal of applied entomology
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• v.20 no.2 s.47
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• pp.98-102
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• 1981

For the investigation of seasonal fluctuation of immature (lavae and pupae) beanfly, infestation rates, and habit, several soybean-cultivars were planted at Kumgok Experiment Farm of KAERI by three different planting times at 25-day intervals. Infestation rates of beanflies were ranged from $85\%\;to\;100\%$ in accordance. with the planting dates, where an increase in infestation rate was found with delay in planting dates. Immature beanflies were already observed from lune 20 by plant dissection counts. Three peaks of the seasonal fluctuation of lava were shown by occurring on July 10, August 10 and 50 during the soybean cultivation, while two peaks of pupal appearances were found. The most high peaks of lavae and pupae occurred on August 10 and 30, respectively. The lava were habitable in the pith or cortex tissue of soybean stem. They prepared tiny hole on the axilla as well as the internode of stem, and then they pupated in the holes from which the adults are able to escape. Immature beanfly seemed to prefer invading to the underground part of the stem when the soybean plants were in young stage.