• Nuclear Engineering and Technology
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• v.40 no.6
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• pp.451-458
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• 2008

After more than 10 years construction, KSTAR (Korea Superconducting Tokamak Advanced Research) had finally completed its assembly in June 2007, and then achieved the goal of first-plasma in July 2008 through the four month's commissioning. KSTAR was constructed with fully superconducting magnets with material of $Nb_3Sn$ and NbTi, and their operation temperatures are maintained below 4.5K by the help of Helium Refrigerator System. During the first-plasma operation, plasmas of maximum current of 133kA and maximum pulse width of 865ms were obtained. The KSTAR Integrated Control System (KICS) has successfully fulfilled its missions of surveillance, device operation, machine protection interlock, and data acquisition and management. These and more were all KSTAR commissioning requirements. For reliable and safe operation of KSTAR, 17 local control systems were developed. Those systems must be integrated into the logically single control system, and operate regardless of their platforms and location installed. In order to meet these requirements, KICS was developed as a network-based distributed system and adopted a new framework, named as EPICS (Experimental Physics and Industrial Control System). Also, KICS has some features in KSTAR operation. It performs not only 24 hour continuous plant operation, but the shot-based real-time feedback control by exchanging the initiatives of operation between a central controller and a plasma control system in accordance with the operation sequence. For the diagnosis and analysis of plasma, 11 types of diagnostic system were implemented in KSTAR, and the acquired data from them were archived using MDSpius (Model Driven System), which is widely used in data management of fusion control systems. This paper will cover the design and implementation of the KSTAR integrated control system and the data management and visualization systems. Commissioning results will be introduced in brief.

• Food Science and Preservation
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• v.13 no.6
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• pp.769-773
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• 2006

This study was to investigate the biological activities of green tea seed methanol extract (GTSME) and compared those of green tea methanol extract (GTME) for using green tea seed as the functional food material. The hydrogen-donating activity of GTSME was over 50% at the $100 {\mu}g/mL$ concentration the activity of GTME was 21.86% at the $1000{\mu}g/mL$ concentration compared with that of control. The MDA (malondialdehyde) production was 60 Mol/g and 50 Mol/g in the mouse liver homogenate teated with GTME and GTSME of $1000{\mu}g/mL$ concentrations, respectively, and the values were lower than 86 Mol/g of control. GTME and GTSME of $1000{\mu}g/mL$ concentration inhibited the proliferation of over 50% and over 20% in A549 and SW480 human cancer cells, respectively. The morphology transformation was shown in the cancer cells treated with GTSME of $500{\mu}g/mL$ with the decrease of cell numbers lower than that of control cells numbers. The NO production was increased in a dose dependent manner in the RAW264.7 macrophage cells treated with GTME and GTSME of 1, 10, 100 and $1000{\mu}g/mL$ concentrations, and the NO production by GTSME was $2.04{\mu}M$ at $100{\mu}g/mL$ concentration, and the value was higher than $0.77{\mu}M$ by GTME.

• Clean Technology
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• v.5 no.1
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• pp.78-85
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• 1999

In the Kimchi manufacturing industry that has recently been on its greatest growth, the rinsing process for salt-pickled Chinese cabbage in a brining step generates a vast amount of rinsing wastewater containing salts, colloids, and organics released from the raw material. In this study, the experimental method was developed to optimize the rinsing water consumption and thus to minimize the rinsing wastewater generation. The continuous counter-current rinsing basin in the actual plant was simulated through the lab-scale three batch-wise rinsing tanks. Rinsing efficiencies for the brined cabbage from the same brining tank were almost in the same level, whereas those varied substantially from source to source in the raw Chinese cabbage provided. When rinsing water used were decreased from 3.3 L/head to 2.7 L/head, no significant change was observed with respect to COD, turbidity, conductivity, $Na^+$, and $Cl^-$ concentrations in the extracted solution of the rinsed cabbage. However, the quality of the extracted solution was badly deteriorated as the amount of rinsing water used dropped down to below 2.7 L/head. The reduction of rinsing water up to 18% was proved to be possible without any negative effect on the quality of the product, Kimchi.

• Clean Technology
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• v.23 no.2
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• pp.133-139
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• 2017

Bio-based plastics containing the biomass content higher than 25 wt% have been considered as environment-friendly materials due to their effects on the reduction in the $CO_2$ emission and petroleum consumption as well as biodegradability after use. In this study, poly vinyl chloride, plant-derived plasticizers, by adding a biodegradable catalyst was observed a change in the biodegradability and physical properties. To produce the oxidative decomposition transparent bio film, which is broken down in the initial percent elongation and physical properties such as tensile strength, it was to test the safety of the product as a food packaging material. Poly vinyl chloride, primary plasticizer, secondary plasticizer, anti fogging agent, the combined stabilizer were mixed in a high speed mixer, then extruded using an extrusion molding machine, after cooling, winding, to produce a oxidative decomposition transparent bio film and the control film, with a thickness of $12{\mu}m$ through winder role. Mechanical properties tensile strength, elongation, and the maximum load elongation and biodegradation test. Transparent bio film produced by biodegradation catalyst is compared with the control film. Tensile strength and elongation of films were found to be no significant difference. Further, as a result of the biodegradation test for 45 days based on the ASTM D6954-04 method, biodegrability of film is 61.4%.

• The Korean Journal of Mycology
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• v.45 no.2
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• pp.91-101
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• 2017

Three species of powdery mildew (Erysiphales) on eggplant (Solanum melongena L.) have been listed in Korea, namely Erysiphe cichoracearum (now genus Golovinomyces), Leveillula taurica, and Sphaerotheca fusca (now genus Podosphaera; syn. Podosphaera xanthii). Since E. cichoracearum was recorded on eggplant for the first time in Korea in 1969, it has been regarded as a major powdery mildew agent on that plant. In 1998, the causal agent of powdery mildew on eggplant was recorded as L. taurica, then as S. fusca in 2002. During our extensive field surveys in Korea, we collected 22 samples of eggplant powdery mildews. Our microscopic observations and molecular sequence analyses showed that all of our samples belonged to the genus Podosphaera, in the absence of either E. cichoracearum or L. taurica, suggesting that P. xanthii is the dominant agent of powdery mildew disease on eggplants in Korea. As there have been no additional findings on L. taurica after the first report on the species, it seems to be a minor species that is rarely found in greenhouses. The presence of E. cichoracearum (syn. Golovinomyces cichoracearum s. lat.) on eggplants is questionable, as the morphological characteristics of E. cichoracearum in the original description of the Korean collection deviate from the morphological variations of this species. In addition, no herbarium material of E. cichoracearum remains. Consequently, it seems that P. xanthii is the main species of powdery mildew on eggplants, whereas L. taurica occurs rarely on eggplants, in Korea. This review provides the historical and recent taxonomy of eggplant powdery mildews in detail.

• Journal of Life Science
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• v.25 no.2
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• pp.189-196
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• 2015

Bacterial diversity was studied in the rhizosphere of Suaeda japonica Makino, which is native to Suncheon Bay in South Korea. Soil samples from several sites were diluted serially, and pure isolation was performed by subculture using marine agar and tryptic soy agar media. Genomic DNA was extracted from 29 pure, isolated bacterial strains, after which their 16S rDNA sequences were amplified and analyzed. Phylogenetic analysis was performed to confirm their genetic relationship. The 29 bacterial strains were classified into five groups: phylum Firmicutes (44.8%), Gamma proteobacteria group (27.6%), Alpha proteobacteria group (10.3%), phylum Bacteriodetes (10.3%), and phylum Actinobacteria (6.8%). The most widely distributed genera were Bacillus (phylum Firmicutes), and Marinobacterium, Halomonas, and Vibrio (Gamma proteobacteria group). To confirm the bacterial diversity in rhizospheres of S. japonica, the diversity index was used at the genus level. The results show that bacterial diversity differed at each of the sampling sites. These 29 bacterial strains are thought to play a major role in material cycling at Suncheon Bay, in overcoming the sea/mud flat-specific environmental stress. Furthermore, some strains are assumed to be involved in a positive interaction with the halophyte S. japonica, as rhizospheric flora, with induction of growth promotion and plant defense mechanism.

• Journal of the Korea Organic Resources Recycling Association
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• v.11 no.1
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• pp.149-153
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• 2003

This study was conducted to survey the utilization possibility of composting system of small scale static pile with animal manure produced from cattle shed and the effect of addition of microorganism on the maturity of compost. Microorganisms added in composting substrate were bacteria+lactobacillus(BL)+photo.(BLP). The composting practiced was a windrow system without aeration equipment and turning was practiced periodically. The water content of substrate mixed with cow manure, rice husk, and sawdust was about 60%. The temperature during the composting process was increased at over $60^{\circ}C$ within 3 days after composting starting. Increase of temperature at the early stage of composting was fasten in BLP and BL than Control. Because the pH of the raw material was high, the changes of pH during composting was little and stabilized in weak alkaline condition. EC value was high for accumulation of manure and urine excreted continuously by animal and the changes of those during composting occurred in 5~10% increase. Reduction rates of C/N ratio were the largest as the 22.7% in BLP and 19.2and 17.5% in BL and Control respectively. In the evaluation of phytotoxicity, there was stabilized within the short time in BLP and not the difference between BL and Control. Treatment of animal manure produced from small scale cattle shed was possible by using the small scale static pile composting system with reasonable water content and turning and the addition of microorganism in composting substrate was effected on the temperature increase at the early stage of composting and reduction of plant toxicity compounds but little on the maturity of compost.

• Journal of Radiation Protection and Research
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• v.41 no.3
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• pp.196-205
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• 2016

Background: The emergency planning zone (EPZ) of the city of Busan is divided into the precautionary actions zone (PAZ) and the urgent protective action planning zone; which have a 5-km radius and a 20-km to 21-km radius from the nuclear power plant site, respectively. In this study, we assumed that a severe accident occurred at Shin-Kori nuclear unit 3 and evaluated the dispersion speed of radiological material at each distance at various wind speeds, and estimated the effective dose equivalent and the evacuation time of PAZ residents with the goal of supporting off-site emergency action planning for the nuclear site. Materials and Methods: The total effective dose equivalent, which shows the effect of released radioactive materials on the residents, was evaluated using the RASCAL 4.2 program. In addition, a survey of 1,036 residents was performed using a standardized questionnaire, and the resident evacuation time according to road and distance was analyzed using the VISSIM 6.0 program. Results and Discussion: According to the results obtained using the VISSIM and RASCAL programs, it would take approximately 80 to 252.2 minutes for permanent residents to move out of the PAZ boundary, 40 to 197.2 minutes for students, 60 to 232.2 minutes for the infirm, such as elderly people and those in a nursing home or hospital, and 30 to 182.2 minutes for those temporarily within the area. Consequently, in the event of any delay in the evacuation, it is estimated that the residents would be exposed to up to $10mSv{\cdot}h^{-1}$ of radiation at the Exclusion Area Boundaries (EAB) boundary and $4-6mSv{\cdot}h^{-1}$ at the PAZ boundary. Conclusion: It was shown that the evacuation time for the residents is adequate in light of the time lapse from the initial moment of a severe accident to the radiation release. However, in order to minimize the evacuation time, it is necessary to maintain a system of close collaboration to avoid traffic congestion and spontaneous evacuation attempts.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.4
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• pp.481-485
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• 2011

This study was to investigate catalpol content and antioxidant activities in five cultivars (Kokang, Suwon 10, Suwon 11, Jiwhang 1 and Korea) of Rehmannia Radix. Catalpol content was analysed by HPLC using $C_{18}$ column ($150{\times}4.6\;mm$, $5{\mu}m$), 1% acetonitrile and a UV detector. The standard curve was found to be a linear regression of y=0.0483x-0.0841 ($R^2$=0.999). The catalpol content ranged from 85.2 mg/g to 144.9 mg/g, of which the Korea was the highest among cultivars. The total phenol content in Rehmannia Radix was 0.358~0.459 mg/g, of which the Korea was the highest among cultivars. The antioxidant activities determined by DPPH and hydroxyl radical scavenging activities were the highest in Korea with $IC_{50}$ of 205.8 mg/g for DPPH radical scavenging activity and $IC_{50}$ of 38.8 mg/g for hydroxyl radical scavenging activity. Based on these results, the Korea among Rehmannia Radix cultivars was suggested to be a potent medicinal plant material for antioxidant activities.

• Journal of the Korean Geotechnical Society
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• v.29 no.5
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• pp.29-38
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• 2013

The G-class cement is commonly used in practice for geothermal well cementing in order to protect a steel casing that is designed to transport hot water/steam from deep subsurface to ground surface during operating a geothermal power plant. In order to maintain optimal performance of geothermal wells, physical properties of the cementing material should be satisfactory. In this paper, relevant factors (i.e., groutability, uniaxial compression strength, thermal conductivity and free fluid content) of the G-class cement were experimentally examined with consideration of various water-cement (w/c) ratios. Important findings through the experiments herein are as follows. (1) Groutability of the G-class cement increases by adding a small dose of retarder. (2) There would be a structural defect caused when the w/c ratio is kept higher in order to secure groutability. (3) Thermal conductivity of the G-class cement is small enough to prevent heat loss from hot steam or water to the outer ground formation during generating electricity. (4) The G-class cement does not form free water channel in cementing a geothermal well. (5) The Phenolphthalein indicator is applicable to the distinction of the G-class cement from the drilling mud.