• 전기학회논문지
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• 제56권10호
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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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• 제33권2호
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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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• 제5권2호
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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.

• 대한안전경영과학회지
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• 제11권3호
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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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• 제23권1호
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• pp.25-37
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• 2012

두 평정자간 평가의 일치정도를 나타내는 합치도로 Cohen (1960)의 ${\pi}$, Scott (1955)의 H, 박미희와 박용규 (2007)의 등 많은 통계량이 제안되어왔다. 모의실험을 통하여 균형적 주변분포에서의 명목형과 순서형 합치도, 두 가지 역설이 발생하는 불균형 주변분포에서의 명목형 합치도들의 편의, 표준오차, 평균오차제곱 분산, 변이계수를 비교한 결과, 모든 경우에서 AC1과 H의 표준오차와 변이계수가 가장 작게 나타났다.

• 동의생리병리학회지
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• 제18권2호
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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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• 제24권1호
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• pp.65-69
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• 2009

본 연구에서 탄소원이 고갈된 후 용존산소농도로 epothilone의 합성을 조절할 수 있음을 증명하였다. 선행연구로써, soluble starch를 탄소원으로 결정하였고, lactose와 yeast extract의 최적농도가 각각 4 g/L, 0 g/L임을 알 수 있었다. 탄소원이 고갈된 환경에서 산소농도가 낮을 경우 균체가 epothilone을 다량으로 합성하였다. 산소 공급을 조절할 수 없는 flask의 경우 배양이 진행되면서 균제농도가 증가하고 자연적으로 산소 농도도 감소하므로 epothilone이 합성되지만, 생물반응기의 경우 탄소원의 고갈 후 산소 농도를 최대한 낮게 유지시키는 것이 epothilone의 생산을 증가시켰다.

• 한국지반환경공학회 논문집
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• 제6권3호
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• pp.63-72
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• 2005

환경친화적 블록에 대한 조도, 세굴, 수류에 대한 안정성, 수중 DO농도 등 특성을 수리실험을 통하여 분석하였다. 아(亞)형 블록의 조도계수는 I형 블록의 조도계수보다 낮았고 아(亞)형블록이 흐름에 더 안정적인 것으로 나타났다. 따라서 아(亞)형블록이 수로의 흐름 소통에 더 효율적일 것으로 기대된다. 아(亞)형 블록에 모래를 채운 경우 수로 바닥의 세굴은 매우 작거나 거의 일어나지 않았으며 안정적인 형태를 유지하였다. 아(亞)형 블록을 조립한 아(亞)형 블록 입체형은 블록간의 결속력으로 인해 수류에 대해 안정하다고 할 수 있다. 아(亞)형 블록을 수로 바닥에 설치한 경우는 I형 블록을 설치한 경우보다 수중의 DO농도가 증가하였다. 따라서 아(亞)형블록이 I형 블록보다는 수중환경에 유리할 것으로 판단된다.

• 한국HCI학회:학술대회논문집
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• 한국HCI학회 2009년도 학술대회
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• pp.295-300
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• 2009

본 논문은 장애인 및 고령자들이 병원과 같은 공공장소에서 복잡한 업무를 수행하는데 있어서, 상황을 인식하고 인식한 상황에 적합한 안내서비스를 제공하는 시스템을 제안한다. 상황인식을 위해 센서로부터 획득한 사용자의 위치정보와 로컬 정보 시스템에서 획득한 사용자의 프로세스정보를 동시에 고려하여 시공간 상황을 인식하고, 이를 바탕으로 사용자에게 필요한 안내서비스를 추론한다. 또한 사용자가 보유한 단말기를 통해 사용자에게 위치, 서비스, 상황정보 안내를 개인화된 형태로 제공한다.

• Mycobiology
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• 제43권3호
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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.