• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.28_29
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• 2009

전력계통의 비접지 계통에 지락 고장이 발생하면 중성점 이동으로 고장이 발생하지 않은 건전상의 전위가 상승한다는 사실은 누구나 다 알고 있다. 이는 전기적으로 균형을 이루고 있는 계통에 지락 고장으로 상간 불균형이 초래되기 때문인데 보통 비접지 계통의 보호는 1상 지락 시는 고장전류가 거의 없기 때문에 영상 과전압을 이용한 한시 보호계전 방식으로, 2중 접지 시는 과전류 계전방식으로 보호 하고 있다. 그런데 고장전류가 없어 상대적으로 파급이 적을 것 같은 1상 지락고장 시 건전 상에 발생한 과전압이 또 다른 고장을 유발, 더 큰 고장으로 진전되어 많은 복구비용을 발생하게 하거나 예상치 못한 현상을 일으켜 고장원인을 분석하고 처리하는데 어려움을 초래하기도 한다. 본 논문은 발전소 비접지 계통에서 발생하는 중성점이동 현상에 대해서 논하고자 한다.

• Proceedings of the KIPE Conference
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• 2018.11a
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• pp.215-216
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• 2018

본 논문에서는 Carrier-Based Pulse Width Modulation(CBPWM)을 사용한 Active Neutral Point Clamped (ANPC) 인버터의 안정적인 고장 허용 운전을 위한 중성점 전압 균형 제어 기법을 제안한다. 제안된 기법은 ANPC 인버터를 구성하고 있는 전력 반도체 스위치의 고장으로 인한 고장 허용 운전 시, 출력 특성이 저하되는 문제점을 해결하기 위해 스위칭 조합의 재구성과 기준 출력전압의 변조를 통한 중성점 전압 균형을 유지한다. 제안된 기법의 타당성은 RT-BOX를 통한 HIL 시뮬레이터를 이용하여 확인하였다.

• Korean Journal of Food Science and Technology
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• v.20 no.4
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• pp.585-593
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• 1988

The lipid contents and neutral lipid components of brown rice, milled rice and bran were studied for four varieties of rice such as Nampung, Milyang #23, Whasung and Jinhung. Total lipid contents of brown rice, milled rice and bran were 2.65%, 1.09% and 20.24% respectively. The ratios of neutral lipids, glycolipids and phospholipids in total lipids were 82.53:12.39:4.08 in brown rice and 87.72:7.02:5.26 in bran. Neutral lipids were separated on the TLC; among them 6 neutral lipids were identified by comparing the RF value of standards. Triglycerides(TG), free fatty acids(FFA) and steryl esters(SE) were major neutral lipid components in brown rice, milled rice and bran. TG content of the bran, compared to that of brown rice and milled rice, was very low in contrast the FFA content was high. The major fatty acids of total lipid and neutral lipid fractions were palmitic, linoleic and oleic acids, comprising over 95% of these classes.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.5
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• pp.819-825
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• 2002

The present study was conducted to investigate the effect of dietary supplementation of sea tangle extracts on the excretion of neutral steroids and bile acid in diabetic rats. Sprague-Dawley rats were fed on AIN-76 based experimental diets containing methanol extracts (2%, w/w) or water extracts (4%, w/w) of sea tangle for 4 weeks. And then they were induced to be diabetic by receiving streptozotocin (45 mg/kg BW) intramuscularly. The dried fecal weight was increased significantly in water extracts group compared with control group. The fecal content of cholesterol was higher in extracts groups of sea tangle than in control group. But there was no significant difference in fecal excretion of cholesterol between methanol and water extracts groups. The fecal excretion of coprostanol was increased significantly in water extracts group compared with the control group. The fecal excretion of bile acid was increased significantly in sea tangle extracts groups compared to the control group. These data suggest that dietary supplementation of sea tangle extracts might reduce the incidence of atherosclerosis through increasing the excretion of neutral steroids.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.1
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• pp.116-122
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• 1997

Rats were adapted to diets containing 10% cellulose,10% sodium alginate and fiber-free diet for 5 weeks. Following a 14 hour fasting, rats were fed 5g of a test meal that provided 50% energy from fat, then killed at 4 hour postprandially. Plasma and lipoprotein fraction-cholesterol levels were lower in sodium alginate-fed animals than in rats fed other diets. Plasma TG did not differ among diet treatments. Increase in TG content of HDL fraction occurred in dietary fiber groups. Intestinal apolipoprotein B level and lipase activity were lower in sodium alginate-fed group than in other dietary groups. These results suggest that chronic consumption of sodium alginate affects plasma cholesterol level as in the case of fiber supplemetation, but is less likely to modify the acute Plasma TG response to high fat meal than if a fiber supplement is incorporated into the meal.

• Journal of Life Science
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• v.15 no.4 s.71
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• pp.613-618
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• 2005

We investigated the effect of chicory (Chicorium intybus) extract on triglyceride concentration and microsomal triglyceride transfer protein (MTP) activity in rats. The effect of water-soluble extract of chicory fed at the $2.0\%\;and\;4.0\%(w/w)$ levels for 2 weeks on the concentration of serum triglyceride and the activity of hepatic microsomal riglyceride transfer protein (MTP) was investigated in male Sprague-Dawley rats. The triglyceride concentrations in serum of the chicory extract fed groups were significantly lower than in the control group. MTP activity, known to be essential for the assembly/secretion of apolipoprotein B-containing lipoproteins, was also significantly lower in the chicory extract groups than in the control group. The concentrations of other lipids in serum and liver and the activity of phosphatidate phosphohydrolase, the rate-limiting enzyme in triglyceride synthesis, showed no significant differences among in the chicory fed groups. These results indicate that dietary chicory extract decrease hepatic MTP activity and serum triglyceride concentration, and therefore reduces hepatic lipoprotein assembly and secretion.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.3 no.1
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• pp.23-30
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• 2005

From measured results of the neutron fields at some principal places within the containment building in a CE type nuclear power plant in operation, the radiation exposure of a worker to the neutron at there was evaluated and the equivalent dose reflecting new recommendation (ICRP 60) was compared with that doing the old one (ICRP 26). The measured neutron field was also compared with calibration neutron field. From the analysis, the following conclusion was obtained: the average neutron radiation weighting factor according to new recommendation is 2.41 to 2.71 times higher than the old one. The average neutorn radiation weighting factor at the measured place was similar to that at calibration neutron field. The average neutron energy at measured place was between 42 and 158 keV and higher than that of calibration field of 500 keV. So, the measured equivalent dose in nuclear power plant could be overestimated compared to the real equivalent dose.

• The Journal of the Korea institute of electronic communication sciences
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• v.6 no.2
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• pp.262-267
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• 2011

In the power system, the transformer's neutral earth reactor line 1 grounding failure may occur. By limiting the magnitude of the failure grounding current flow, it will aid to reduce the failure of the transformer. Consequently, this also may avoid the failure of the disconnection of the industrial insulator line that cause by melting. Besides, utilizing the decreasing circuit breaker or others related equipment can use to avoid the possibility of explosion of the transformer. If the failure happen during the operation of the power system, a huge interference will definitely may occur. Therefore, by installing the DONGBUSAN S/S #3M.Tr neutral earth reactor among TOP and BOTTOM BRACE part in the power system, the causes of the rising temperature and reason of the over-current flow that cause by over-current can be analyze.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.5
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• pp.384-390
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• 2020

Purpose: Organophosphate insecticide poisoning can have clinically fatal results. This study aimed to evaluate the relationship between the neutrophil/lymphocyte ratio (NLR) and the occurrence of death in patients with organophosphate insecticide poisoning. Methods: For this retrospective study, data on patients with organophosphate insecticide poisoning who visited the emergency room between January 2008 and November 2018 were collected. The NLR was measured at the time of arrival in the emergency room. The patients were divided into survival and death groups. Results: Overall, 150 patients were enrolled: 15 (10%) in the death group and 135 (90%) in the survival group. In the univariate analysis, the following variables were significantly different between the two groups: age, white blood cell count, amylase level, creatinine level, Acute Physiology And Chronic Health Evaluation (APACHE) II score, and NLR. In the logistic regression analysis of variables with significant differences in the univariate analysis, there were significant differences between the two groups with respect to age, APACHE II score, and NLR. The NLR was significantly higher in the death group than in the survival group (20.83 ± 22.24 vs. 7.38 ± 6.06, p=0.036). Conclusion: High NLR in patients with organophosphate insecticide poisoning may be useful in predicting mortality.

• Analytical Science and Technology
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• v.14 no.4
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• pp.1075-1081
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• 2001

Instrumental Neutron Activation Analysis as a representative method of nuclear analytical technique, has advantages of non-destructive, simultaneous multi-element analysis with the characteristics of absolute measurement method. Up to date, $k_0$-quantitative method which is accurate, convenient and user-friendly, has been generalized world-widely. In this study, it is intented to introduce the general concept of $k_0$-method and to measure $k_0$-parameters for the future implementation to our NAA system. For this objectives, the definition of relevant factors for the quantitative analysis and the equation for the experimental determination of parameters such as $Q_0$(${\alpha}$) and f were summarized. Furthermore, a foundation for the $k_0$-standardization method was prepared through the measurement of ${\alpha}$ and f-value which depend on the specific character of irradiation hole at NAA#1-hole of HANARO research reactor.