• Journal of Korean Society of Forest Science
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• v.8 no.1
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• pp.140-148
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• 1968

Ginkgo biloba L., which was distributed in Korea, was x-rayed with 100, 250, 500, 1000, 2000, 6000R. The results of responses about germination, morphological variations in seedling and early stage growth may be summarized as follows : 1. The germination percent was decreased with X-ray increasing dose from 500R except the slight stimulation of 100R. 2. The germination $LD_{50}$ seemed to be 765R. 3. The seedling height was depressed significantly but only slightly in 100R. 4. The loaf index was increased proportionally to high dose but T/R ratio was reduced apparently. 5. The dry or fresh weight decreased from 250R. It was highly significant except 100R. 6. Many morphological variations were indicated in plants.

• The Journal of Korean Obstetrics and Gynecology
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• v.28 no.2
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• pp.55-75
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• 2015

Objectives : The object of this study was to evaluate the effect of Insamyangyoung-tang aqueous extracts (ISYYT) on the propylthiouracil (PTU) induced rat hypothyroidism. Methods : The rats were divided into 6 groups : intact control, PTU control, Levothyroxine (LT ₄ ), 500, 250 and 125 mg/kg ISYYT treated groups. In ISYYT treated groups, PTU and ISYYT were administered for 4 weeks after 500, 250 and 125 mg/kg ISYYT were administered for 2 weeks. In LT ₄ group, PTU and LT ₄ were administered for 4 weeks. The changes were observed : the weigh, serum thyroid hormone levels, serum sex hormone levels, serum lipid profiles, serum liver enzyme levels, liver and testis antioxidant defense system, histopathology of thyroid gland, liver, epididymis, prostate and testis. Results were compared with PTU control group in this experiment. Results : In comparison with PTU control group, 500 and 250 mg/kg ISYYT treated groups showed significant increase of body, thyroid, liver, testis, epididymis and prostate weights, decrease of serum TSH levels with increase of serum T3 and T4 level, increase of serum testosterone and DHT levels with decrease of serum FSH levels, decrease of serum HDL with increase of TG and increase of serum AST levels. Histopathological inspections of hepatic and male reproductive organ damage induced by PTU were improved. And the changes of antioxidant defense system of Liver and testis induced by PTU were improve. There was no significant difference between 125 mg/kg ISYYT treated group and PTU control group in this experiment. Conclusions : The results obtained in this study considered that Insamyangyoung-tang may be effective in hypothyroidism and related organ damages.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.38 no.6
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• pp.347-352
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• 2005

These experiments investigated the conditioning pattern and the nitrification efficiency of a fluidized sand biofilter (FSB) for seawater application. The FSB fed artificial nutrient was fully conditioned within 22 weeks. The maximum nitrification efficiency of the FSB was achieved at a superficial water velocity (SWV) of 1.0 cm/sec. After fixing the superficial water velocity at 1.0 cm/sec, the nitrification rates of the FSB were assessed at 3 total ammonia nitrogen (TAN) loading rates (250, 500, 1,000 g TAN/$m^3$/day) and 3 water temperatures (12, 16, $20^{\circ}C$). The TAN concentration in the simulated culture tank ranged from 2.87 to 9.72 mg/L at TAN loading rate of 1,000 g TAN/$m^3$/day, while that ranged from 0.45 to 1.26 mg/L at TAN loading rate of 500 g TAN/$m^3$/day. The ranges of TAN concentration in the former were too high for aquatic organisms and those in the latter were acceptable. Therefore, the safe TAN loading rate for the FSB in seawater conditions was decided as 500 g TA/$m^3$/day. From these results, daily TAN removal rates (g TAN/$m^3$/day) of FSB under conditions of inlet TAN concentration (C, mg/L) and water temperature (T, $^{\circ}C$) were calculated by the following non-linear multi-regression equation: TAN removal rate: f(z)=-1,311.295+655.714LnT+225.775LnC ($r^2=0.962$).

• YAKHAK HOEJI
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• v.47 no.4
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• pp.239-243
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• 2003

Metformin is an oral antihyperglycemic agent used in the therapy of noninsulin-dependent diabetes mellitus and does not cause hypoglycemia at the therapeutic dose. The purpose of the present study was to evaluate the bioequivalence of two metformin hydrochloride tablets, Glucophage tablet (DaeWoong Pharmaceutical Co., reference drug) and Dybis tablet (Shinpoong Pharmaceutical Co., test drug), according to the guidelines of Korea Food and Drug Administration(KFDA). Twenty-four normal volunteers, 26.6$\pm$4.01 years in age and 60.6$\pm$9.80 kg in body weight, were divided into two groups and a randomized $2{\times}2$ cross-over study was employed. After one tablet containing 500 mg of metformin hydrochloride was orally administered, blood was taken at predetermined time intervals and the concentrations of metformin hydrochloride in serum were determined using HPLC with UV detector. The pharmacokinetic parameters such as AUCt, Cmax and Tmax were calculated and ANOVA test was utilized for the statistical analysis of the parameters. The results showed that the differences in AUCt, Cmax and Tmax between two products were -1.05％, -6.76％ and -4.51％, respectively, when calculated against the reference drug. The 90％ confidence intervals using logarithmically transformed data were within the acceptance range of log0.8$\leq$$\delta$$\leq$log1.25 (e.g., log0.9082$\leq$$\delta$$\leq$log1.0906 and log0.8188$\leq$$\delta$$\leq$log1.0392 for $AUC_{t}$ and $C_{max}$, respectively). The 90％ confidence intervals using untransformed data was within $\pm$20％ (e.g., -17.66％$\leq$$\delta$$\leq$8.63％ for $T_{max}$). All parameters met the criteria of KFDA for bioequivalence, indicating that Dybis tablets (Shinpoong Pharmaceutical Co.) is bioequivalent to Glucophage tablets (DaeWoong Pharmaceutical Co.).

• Journal of the Korean Society for Precision Engineering
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• v.30 no.2
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• pp.236-240
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• 2013

In this presentation, we propose a fabrication method of PDMS stencil to apply into a localized culture of NIH/3T3 cells. PDMS stencil was fabricated by nitrogen gas blowing and soft lithography from preparing SU-8 master mold by photolithography. PDMS stencil pattern was production of the circle size 20 to $500{\mu}m$. In the culture test of PDMS stencil, a stencil was placed on a glass disk. The NIH/3T3 cells were successfully cultured into micropatterns by using the PDMS stencil. The results showed that cells could be cultured into micropatterns with precisely controlled manner at any shapes and specific size for bioscience study and bioengineering applications.

• Communications of the Korean Mathematical Society
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• v.28 no.3
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• pp.487-500
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• 2013

In this paper we provide a brief introduction to the continuity of approximate point spectrum on the algebra B(X), using basic properties of Fredholm operators and the SVEP condition. Also, we give an example showing that in general it not holds that if the spectrum is continuous an operator T, then for each ${\lambda}{\in}{\sigma}_{s-F}(T){\setminus}\overline{{\rho}^{\pm}_{s-F}(T)}$ and ${\in}$ > 0, the ball $B({\lambda},{\in})$ contains a component of ${\sigma}_{s-F}(T)$, contrary to what has been announced in [J. B. Conway and B. B. Morrel, Operators that are points of spectral continuity II, Integral Equations Operator Theory 4 (1981), 459-503] page 462.

• Electronics and Telecommunications Trends
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• v.31 no.1
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• pp.68-77
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• 2016

최근 들어 5G 이동통신 시스템을 위한 표준화 및 기술개발이 본격화되고 있으며, 기존 이동통신 시스템과 차별화되는 5G 이동통신 시스템의 대표적인 목표 중 하나는 사람이 휴대하는 단말기뿐만 아니라 생활 속 모든 사물을 네트워크에 연결하여 정보를 생성하고 공유하는 초연결 네트워크(Internet of Things: IoT) 구축이다. 시장 조사기관이나 다수의 전문가들은 2020년경에는 전 세계적으로 약 500억개의 디바이스가 네트워크에 연결되는 등 사물 디바이스의 폭발적 증가를 예상하며, 이를 통한 부가가치 창출과 시장이 급격히 성장할 것으로 전망하고 있다. 본고에서는 초다수의 사물 디바이스 수용을 위한 5G massive IoT 기술동향 및 이와 관련하여 현재 진행되는 3GPP 표준화 동향에 대해 기술한다.

• Analytical Science and Technology
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• v.14 no.6
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• pp.510-515
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• 2001

There has been an increasing need for analytical methods of dissolved total iron (tFe) that are highly sensitive, rapid, inexpensive and simple for environmental samples. A sensitive flow injection analysis (FIA) method for determining the concentration of tFe in environmental samples was developed. The proposed method required 10 minutes and only $500{\mu}L$ of sample for and analysis. The standard deviation was 5.0% at $0.5{\mu}gL^{-1}$ (n=6), and the detection limit was $0.075{\mu}gL^{-1}$. The developed method was applied to environmental samples such as tap water, mineral water, rain, snow and cloud water. Since this FIA system was free form interferences of coexisting ions commonly found in samples, sub-${\mu}gL^{-1}$ level of tFe could be easily determined without further preconcentration and separation.

• Journal of the Korean Society of Industry Convergence
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• v.9 no.2
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• pp.105-110
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• 2006

Valve-housing parts in car steering system is a part of steering system and then take charge of the main functions for car steering system to reduce driver's handling-force. Recently it is still not developed reliable casting for many cars, so it produce as a Gravity casting which is more than triple for producing cost in Korea. In this research, we had conducted that 350t aluminum die casting is superior to mechanical property from established over 500t or not for Valve-housing, a parts of steering system which were produced as a cast-iron product and the most suitable conditions to extruding as die casting.

• Korean Journal of Poultry Science
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• v.33 no.3
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• pp.211-215
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• 2006

This study was carried out to determine whether genistein implants in laying hens could be transferred into their eggs. 250 mg genistein pellet was implanted two or four subcutaneously in the neck of laying hens. The contents of genistein in egg yolk transferred were analyzed with HPLC-MS. In 500 mg genistein pellets, it was detected as 395 ng/egg yolk on the day 18 after implanting and maintained as 546 ng/egg yolk after the day 59. In 1,000 mg, genistein was detected as 240 ng/egg yolk on the day 13, as 514 ng/egg yolk on the day 30 and maintained over 59 days. In conclusion, the direct genistein implants could be more twenty times efficiently transferred to egg yolks than dietary supplement.