• 한국수산과학회지
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• 제37권3호
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• pp.209-214
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• 2004

A method for rapid acute toxicity test based on temperature control of Ceriodaphnia dubia has been developed and evaluated. A new toxicity test based on temperature control (TTBTC) which are based on temperature control, was developed and compared for the adsorption of the better methodology for short-term toxicity screening. Initially, daphnid larval are exposed to toxicants and at the same time the temperature of the water bath containing media is increased to high temperature $(35.5^{\circ}C).$ After 1.25 hrs of contact time, the number of the daphnids, either living (no toxic effect) or dead (toxic effect), is counted by the naked eyes. Effect of exposure time on test sensitivity was not significantly different between 1 to 1.5 hr. Comparison of the rapid 1.25 hr acute toxicity test developed in this study and the standard 48 hr acute toxicity test using heavy metals, cyanide and pentachlorophenol indicated that the 1.25 hour test provides an acceptable level of sensitivity in toxicity test for C. dubia.

• The Korean Journal of Physiology and Pharmacology
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• 제5권4호
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• pp.315-321
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• 2001

This study was aimed to evaluate the effects of quercetin and desferrioxamine on the development of the reflux esophagitis induced surgically, on gastric secretion and on lipid peroxidation which is a marker of oxidative stress. Omeprazole was used as a positive control drug. Omeprazole significantly and dose-dependently prevented the development of reflux esophagitis, but quercetin or desferrioxamine prevented only at high dose. Omeprazole significantly and dose-dependently inhibited the gastric acid secretion (gastric volume, pH and acid output), but quercetin or desferrioxamine did not inhibit. Malonyldialdehyde content, the end product of lipid peroxidation, increased significantly after the induction of reflux esophagitis. Omeprazole prevented lipid peroxidation. Quercetin and desferrioxamine inhibited the lipid peroxidation independent of their actions on gastric secretion. This result indicates that omeprazole confirmed preventing effect of rat reflux esophagitis, but quercetin and desferrioxamine inhibited esophagitis by reduction of lipid peroxidation irrespective of gastric acid secretion.

• Natural Product Sciences
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• 제19권2호
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• pp.137-144
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• 2013

Phytochemical constituents were isolated from the seeds of tartary buckwheat (Fagopyrum tataricum) by open column chromatography. Their structures were elucidated as ${\beta}$-sitosterol (1), ${\beta}$-sitosterol-3-O-glucoside (2), oleanolic acid (3), kaempferol (4), quercetin (5), kaempferol-3-O-rutinoside (6), and quercetin-3-O-rutinoside (7) on the basis of spectroscopic analysis including $^1H$-, $^{13}C$-NMR, and MS. To our knowledge, oleanolic acid (3) has been isolated for the first time from the seeds of Fagopyrum species. The total contents of compounds 4 - 7 were 0.500 mg/g in Daesan maemil, 0.312 mg/g in Yangjul maemil, and 2.185 mg/g in tartary buckwheat.

• 한국정보통신설비학회:학술대회논문집
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• 한국정보통신설비학회 2003년도 하계학술대회
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• pp.35-37
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• 2003

본 논문에서는 진행파형 전계 흡수 광 변조기를 3차원 FDTD를 이용하여 도파관의 폭과 진성영역의 두께 그리고 N-도핑층의 도핑수준을 변화시키면서 최적화된 구조를 설계하였다. 제작된 소자의 구조는 진성영역의 두께는 $0.9{\mu}m$, 도파관의 폭은 $6{\mu}m$이며 전체 소자의 길이는 $700{\mu}m$ 이다. 제작된 소자의 마이크로파 특성을 측정하였으며 마이크로파 특성과 광 특성을 사용하여 주파수 응답특성을 추정하였다. 소자의 길이가 $400{\mu}m$ 일 때 17.8 GHz의 주파수 응답특성을 얻었다.

• Bulletin of the Korean Chemical Society
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• 제35권2호
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• pp.345-346
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• 2014

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 A
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• pp.299-301
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• 1998

The torque characteristic of an induction motor is affected greatly by the slot shape at which the conductors of the rotor are located. In this paper, the three analysis model; general type, deep slot type, double squirrel-cage type, of which the slot shapes are different, were analyzed by FEM at no load, at rated load, and at standstill respectively. The flux distribution and air-gap flux density were also obtained. From the above result, it was confirmed that the analysis models of deep slot and double squirrel-cage had more desirable characteristics than those of general squirrel-cage.

• 한국산림과학회지
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• 제95권5호
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• pp.580-584
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• 2006

This study was conducted to clarify the characteristics of breeding bird communities between deciduous and coniferous forests from April to June 2005 in Mt. Namsan, Seoul, Korea. Two 10ha areas were selected for territory mapping of breeding bird communities. Number of breeding bird species, pairs,density and bird species diversity index were higher in deciduous forest with increasing amount of foliage in the forest profile or as forest structures developed compared with coniferous forest. The number of in coniferous forest. The differences in habitat structure between both study areas are very likely to have influenced how breeding birds used the available habitat. Forest structure and its interactions with birds should be consideration in forest management for birds and their habitat.

• Journal of Applied Biological Chemistry
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• 제62권1호
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• pp.87-91
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• 2019

The contents of major ginsenosides (ginsenosides Rb1, ginsenoside Rc, ginsenoside Rd, ginsenoside Re, ginsenoside Rf, and ginsenoside Rg1) in ginseng cultivated in different areas in Korea, ginseng that underwent different cultivation processes and ages, and ginseng cultivated in different countries were determined using high-performance liquid chromatography equipped with UV/VIS detector. Ginsenoside Rc was the most abundant ginsenoside in all different ginseng samples. The highest total concentration of major ginsenosides was found in the ginseng cultivated in Jinan (0.931 mg/g) and 4-year grown red ginseng (1.785 mg/g). Major ginsenosides were the most abundant in Korean ginseng (1.264 mg/g), compared to those in Chinese and American ginseng. The results of this study showed the different contents of major ginsenosides in the ginseng samples tested and emphasized which sample could contain high yield of ginsenosides.

• 한방비만학회지
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• 제12권2호
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• pp.8-16
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• 2012

Objectives: This study is designed to report the correlation between Body Mass Index(BMI), Heart Rate Variability(HRV), stess, drinking alcohol, coffee and smoking. Methods: From 1st January 2010 to 31st December 2012, We tested on 458 patients who hospitalized in Cheong Yeon Korean Medicine Hospital for reducing their weights, then we collected the statistical analysis with the result of their HRV and the special survey. Results: This experiment was studied on total 458 patients, 27 were men and 431 were women. The average of the age of men was $28.23{\pm}4.22$ and $24.31{\pm}385$ was women. There were significant differences in BMI, Low frequency(LF), High frequency(HF), stress score, frequency of drinking alcohol, smoking and drinking coffee followed by their ages. When we looked at the correlation between obesity with smoking and drinking coffee, we can see that the BMI increased, the frequency of drinking alcohol was decreased, however there were no statistic correlation in smoking and drinking coffee with BMI. Conclusions: With the result of HRV, we can suggest the BMI and stress score are correlated each other but we need further studies about passive stress relief by taking favourite food such as drinking alcohol, smoking, drinking coffee, etc.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2006년도 전력전자학술대회 논문집
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• pp.277-280
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• 2006

Recently, the high frequency isolated boost DC/DC converter has been widely used for the PCS (Power Conditioning System) system because of its small size and low cost. However, the high frequency isolated boost DC/DC converters applied the conventional voltage-fed converter and current-fed converter have the problems such as the high conduction losses and the surge voltage due to the high circulating current and the leakage inductance, respectively. To overcome this problems, in this paper the secondary LLC resonant converter is proposed, and the experimental results of the secondary LLC series resonant converter for boost DC/DC converter are verified on the simulation based on the theoretical analysis and the 1kW experimental prototype.