• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.10
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• pp.1775-1781
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• 2007

In this paper, the rotational loss of the superconductor flywheel energy storage system (SFES) by motor/generator stator core was assessed. To do this, the vertical axial type SFES with journal type superconductor bearing was manufactured. To quantitatively assess the rotational loss by the stator core, the rotational losses by superconductor bearing and the degree of a vacuum were measured. In case of variation of the inner radius and outer radius of the stator core, the rotational losses were measured. From the experimental results, It is confirmed that the rotational loss can be reduced by means of the optimal stator core design.

• Current Research on Agriculture and Life Sciences
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• v.33 no.2
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• pp.65-68
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• 2015

Hunter's color value "a" in dried-persimmon of table and full ripe fruit was higher than that in unripe fruit. In case of soluble solid content, full ripe fruit was $50^{\circ}Brix$, the highest degree, while unripe fruit was $40^{\circ}Brix$, the lowest degree. PPO activation of unripe fruit was 4.7, which was higher than table-ripe fruit (0.7) and full ripe (1.0). Polyphenol oxidase activation remained even while drying, but there was no difference in PPO activation degree as drying period increased. Total phenol content of unripe fruit was 101.4, which was higher than table-ripe fruit (57.5) and full ripe fruit (67.4). Total phenol content level increased as drying period increased, which was based on fresh weight. Hardness of unripe and table ripe fruit continued to decrease until three weeks during softening. After that, hardness was high and it started drying. However, in full ripe fruit, hardness increased after two weeks and softening was fast during the drying period, and its weight reduction rate was lower than that of unripe and table ripe fruit.

• Biotechnology and Bioprocess Engineering:BBE
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• v.5 no.2
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• pp.130-135
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• 2000

The characteristics of two different modes of perfusion culture, intermittent and continuous bleedings, were investigated by culturing the hybridoma cells producing von Willebrand Factor (vWF) monoclonal antibody (McAb) in a 15 L bioreactor without clogging the filter. Both culture methods exhibited similar profiles of cell density and metabolite concentrations during the culture period at the cell concentration of around 1${\times}$107 cells/mL. When the perfusion rate was increased, the intermittrnt bleeding culture showed problems of ammonia accumulation and decrease of cell viability. The continuous bleeding culture in terms of nutrient consumption and metabolite production kinetics. But the analysis of specific oxygen consumption rate showed that the specific oxygen consumption rate of intermittent bleeding culture was similar to that of exponential growth phase. The continuous bleeding culture showed higher specific oxygen consumption rate of intermittent bleeding culture. finally we proved the possibility of long-term operation of continuous bleeding culture and produced approximately 40 g of vWF McAb in a 15L bioreactor after one-month operation.

• Journal of the Korea Safety Management & Science
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• v.11 no.3
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• pp.19-26
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• 2009

It is becoming more and more important to develop safety-critical systems with special attention. Examples of the safety-critical systems include the mass transportation systems such as high speed trains, airplanes, ships and so forth. Safety critical issues can also exist in the development of atomic power plants that are attracting a great deal of attention recently as oil prices are sky-rocketing. Note that the safety-critical systems are in general large-scale and very complex for which case the effects of adopting the systems engineering (SE) approach has been quite phenomenal. Furthermore, safety-critical requirements should necessarily be realized in the design phase and be effectively maintained thereafter. In light of these comments, we have considered our approach to developing safety-critical systems to be based on the method combining the systems engineering and safety management processes. To do so, we have developed a design environment by constructing a whole life cycle model in two steps. In the first step, the integrated process model was developed by integrating the SE (ISO/IEC 15283) and systems safety (e.g., hazard analysis) activities and implemented in a computer-aided SE tool environment. The model was represented by three hierarchical levels: the life-cycle level, the process level, and the activity level. As a result, one can see from the model when and how the required SE and safety processes have to be carried out concurrently and iterately. Finally, the design environment was verified by the computer simulation.

• Journal of the Korean Data and Information Science Society
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• v.23 no.1
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• pp.25-37
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• 2012

Many statistics, such as Cohen's (1960) ${\kappa}$, Scott's (1955) ${\pi}$, and Park and Park's (2007) H have been proposed as measures of agreement to represent inter-rater reliability. This study compared bias, SE, MSE, and CV of the measures of agreement with nominal and ordinal categories in the balanced marginal distributions, and those with nominal categories in the two paradoxical situations. As a result, in all cases, AC1and Hhad smaller SE and CV.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.2
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• pp.606-611
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• 2004

In East-South Asia it has been known that Korean ginseng(Panax ginseng) increases blood pressure, whereas American ginseng(Panax quinquefolius) doesn't. This study was designed to find out if Korean ginseng really could increase blood pressure comparing with American ginseng. Double-blind randomized controlled trials on blood pressure and pulse rate of Korean ginseng and American ginseng in Koreans and Chineses was performed. There was no significant difference on blood pressure and pulse rate between Korean ginseng and American ginseng in both Koreans and Chineses by repeated-measures ANOVA. It was revealed that Korean ginseng does not increase blood pressure. Maybe the concept that Korean ginseng increases blood pressure is concerned with commercial interests dealing with American Ginseng.

• KSBB Journal
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• v.24 no.1
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• pp.65-69
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• 2009

The biological production of a potent anticancer agent, epothilone, by Sorangium cellulosum was carried out using flask and fermentor cultures. Soluble starch was selected as the main carbon source and the concentrations of lactose and yeast extract were optimized at 4 and 0 g/L, respectively, when using the flask cultures. In the fermentor cultures, the cells were cultivated at a high DO level of more than 80% of air saturation in the growth stage and then the DO level was controlled at about 50, 20 or 1-2% when the carbon source was exhausted. The epothilone production increased with decreasing DO level after the exhaustion of the carbon source, and the maximum concentration of epothilone was 5.4 mg/L. It was found that the DO level had significant regulation effects on the epothilone production.

• Journal of the Korean GEO-environmental Society
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• v.6 no.3
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• pp.63-72
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• 2005

The characteristics of environmentally friendly block, roughness, erosion, stability and dissolved oxygen(DO) were investigated by hydraulic experiment. It was found that the roughness of A-block was lower than I block and A block was more stable to the variation of flow. So it is expected that A-block will be more effective to the channel flow. It was also found that the erosion of channel bed was very small or rarely occurred and stable in the case of 3-dimensional A-block filled with sand. And 3-dimensional A-blocks assembled with A-blocks were more stable against the flow force than I block because of the united force of A-blocks. When the bed of channel was paved with 3-dimensional A-blocks, DO was increased higher than I block. So it is expected that A-block will be more advantageous to underwater environment than I block.

• 한국HCI학회:학술대회논문집
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• 2009.02a
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• pp.295-300
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• 2009

This paper presents a context-aware information service system in public places that have complex processes, for the disabled and the elderly. The system infers context of a user which is derived from the user's demand, then it informs to the user -what to do, where to go-according to the context. Our system gets user's context from sensor data and informations from the local information system. The system provides more suitable information with a knowledge model, which organizes location and process data coordinately. The information is provided personally to the user, with mobile devices.

• Mycobiology
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• v.43 no.3
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• pp.266-271
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• 2015

Several types of yeasts were isolated from wild flowers around Jangseong Lake in Jeollanam-do, Republic of Korea and identified by comparing the nucleotide sequences of the PCR amplicons for the D1/D2 variable domain of the 26S ribosomal DNA using Basic Local Alignment Search Tool (BLAST) analysis. In total, 60 strains from 18 species were isolated, and Pseudozyma spp. (27 strains), which included Pseudozyma rugulosa (7 strains) and Pseudozyma aphidis (6 strains), was dominant species. Among the 60 strains, Bullera coprosmaensis JS00600 represented a newly recorded yeast strain in Korea, and its microbiological characteristics were investigated. The yeast cell has an oval-shaped morphology measuring $1.4{\times}1.7{\mu}m$ in size. Bullera coprosmaensis JS00600 is an asporous yeast that exhibits no pseudomycelium formation. It grew well in vitamin-free medium as well as in yeast extract-malt extract broth and yeast extract-peptone-dextrose (YPD) broth, and it is halotolerant growing in 10% NaCl-containing YPD broth.