• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.35 no.5
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• pp.494-498
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• 2022

In this study, SiO₂ 20 phr, ATH 70 phr, and platinum flame retardant were mixed with raw silicone rubber and -10 kV was applied to measure electrostatic charge attenuation voltage, surface resistance, and volume resistance, and the following conclusions were obtained. When the platinum flame retardant was 0 phr, the humidity 74.6% and the temperature was 21.8℃, the potential was half-reduced to 0.63 kV, 0.57 kV, and 0.44 kV when the applied voltage was changed from -10 kV to -8 kV, and the time halved to 50% was increased to 2.40 seconds, 2.47 seconds, and 2.61 seconds. It was confirmed that as the platinum flame retardant increased from 0.1 to 0.3 phr, the potential half-reduced to 0.67 kV, 0.60 kV, and 0.595 kV decreased, and the charge potential attenuation time half-reduced to 50% decreased to 3.44 seconds, 1.78 seconds, and 1.60 seconds. It was confirmed that the surface resistance increased as the humidity decreased, and the volume resistance decreased as the platinum flame retardant increased.

• Advances in nano research
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• v.4 no.3
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• pp.167-179
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• 2016

The detailed study of acute and sub-acute toxicity of the complex polyvinylpyrrolidon (PVP 20 kDa)-wrapped fullerene $C_{60}$ after intraperitoneal (ip) administration was carried out on adult male Wistar rats. The $LD_{50}$ value of $C_{60}/PVP$ complex was found to be 7, 8 g/kg. In sub-acute study which lasted for 30 days the rats were exposed to daily administration of the complex in the doses of 350 or 700 mg/kg. All animals survived during the study and had no significant changes in clinical signs, organ weight, hematological and biochemical parameters of blood. The electrophysiological properties of myocardium and the excretory function of kidneys remained normal. Histological analysis of liver, kidney and spleen at the end of the study also did not demonstrate toxic alterations. It was thus established that intraperitoneal administration of complex $C_{60}/PVP$ has no toxic effect. These results suggest that $C_{60}/PVP$ has no acute and sub-acute toxicity and is a perspective substance for potential application in biology and medicine.

• Journal of Korea Foundry Society
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• v.4 no.1
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• pp.56-60
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• 1984

• Nuclear Engineering and Technology
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• v.31 no.6
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• pp.595-607
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• 1999

The reaction cross-sections of $^{nat}$Ti(p,X)$^{48}$ V, $^{nat}$Fe(p,X)$^{56}$ Co, $^{nat}$Cu(p,X)$^{65}$ Zn and $^{nat}$Mo(p,X)$^{96}$ Tc for TLA application are calculated in the frame of the ECIS-GNASH code system up to 60 MeV. The calculated results are compared with the experimental data taken from the EXFOR at the NEA Data Bank. A preliminary calculation with the global optical parameters of Varner et al. shows considerable differences from the experimental data at low energy range. The global optical parameters for the imaginary volume potential and the diffuseness of the imaginary potential are adjusted to achieve a better description of the experimental data in the vicinities of peak position below 16 MeV. 16 MeV.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.1
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• pp.60.1-60.1
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• 2012

구경 3.6m의 캐나다-프랑스-하와이 망원경(Canada-France-Hawaii Telescope, CFHT)의 주 초점에 설치된 CFH12K CCD 카메라를 이용하여 늙은 산개성단 NGC 1245와 NGC 2506에 대한 V와 I필터를 이용한 CCD측광을 수행하였다. 관측된 영역은 NGC 1245는 84'${\times}$82', NGC 2506은 42'${\times}$81'이고, 한계등급 V ${\approx}$ 23등급까지 관측하였다. 이론적인 등연령곡선을 사용하여 NGC 1245와 NGC 2506에 대해 각각 물리량 E(B-V) = 0.2, 0.03, (V-M_V)_0 = 12.5, 12.5, log(age) = 9.0, 9.3으로 구하였다. 이로부터 MV ${\approx}$ 10등급까지의 광도함수와 질량함수를 구하였다. NGC 1245와 NGC 2506의 질량함수의 기울기를 각각 ${\Gamma}$ = -1.26${\pm}$0.04, ${\Gamma}$ = -1.27${\pm}$0.07로 얻었고, 이들의 기울기는 태양부근의 낱별의 질량함수의 기울기에 비해 완만하다. 이는 성단에서 질량이 작은 별들의 질량 증발에 의한 역학적 진화의 효과로 보인다. 본 발표에서는 관측 내용과 그 결과를 소개하고자 한다.

• Korean Journal of Food Science and Technology
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• v.28 no.6
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• pp.1045-1051
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• 1996

The influence of electrolyzed acid-water (oxidation-reduction potential (ORP): above 1,150 mV, pH : 2.5) on the survival of some microorganisms was investigated. It was observed that the ORP of electrolyzed acid-water was kept at the level of above 1,000 mV for 15 days at room temperature. Escherichia coli. Salmonella typhi, Staphylococcus aureus and Saccharomyces cerevisiae were not detected after 10 to 40 min in electrolyzed acid-water. However, Bacillus cereus showed higher tolerance to electrolyzed acid-water than other test microorganisms. After 60 min of inoculation, only 0.4% of initial population remained. The investigation of surface sterilization effect on some vegetables was carried out too. Total count of cabbage, Chinese cabbage and kale were reduced to below 3% of initial count, and no coliform was detected after 20 to 60 min of immersion in 5 volumes of electrolyzed acid-water. In the lettuce, total and coliform counts were reduced to 90% and 2% of initial population. This study shows that the electrolyzed acid-water has a potential for the sterilization of food products such as vegetables and fruits which cannot be thermally sterilized.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.310-311
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• 2011

본 논문에서는 제주 한림 풍력발전소와 한림 변전소간에 구축할 예정인 ${\pm}80kV$ 60MW HVDC 시스템의 절연 설계를 위해, 각 구성품의 절연 등급을 수 계산으로 설계하였고 PSCAD로 검증하였다. 해당 HVDC 시스템에 영향을 미칠 수 있는 주요 임펄스 중 긴 시간을 가지고 빈번하게 발생 하는 Switching Impulse가 미치는 영향을 모든 상황을 고려하여 모의하였고 수 계산으로 설계된 절연 등급을 검증 하였다.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.352-353
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• 2011

본 논문에서는 제주 한림 풍력발전소와 한림 변전소 간에 구축할 예정인 ${\pm}80kV$ 60MW HVDC 시스템의 절연 설계를 위해, 각 구성품의 절연 등급을 수 계산으로 설계하였고 PSCAD로 검증하였다. 각 부분의 절연설계 부분 중, 특히 AC측의 선로에 설치되어 고조파를 저감하는 AC Filter의 절연설계는 고려할 사항이 많다. AC측 선로의 사고, 임펄스 그리고 구성 소자인 인덕터와 커패시터의 설치 구성에 따라 AC Filter의 절연설계가 달라질 수 있다. 따라서 Filter 종류 및 주변 상황요소가 미치는 영향 등 모든 상황을 고려하여 모의하였고 수 계산으로 설계된 절연등급을 검증하였다.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.392-393
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• 2011

본 논문에서는 제주 한림 풍력발전소와 한림 변전소간에 구축할 예정인 ${\pm}80kV$ 60MW HVDC 시스템의 절연 설계를 위해, 각 구성품의 절연 등급을 수 계산으로 설계하였다. 계산된 절연등급을 기반으로 한림 변전소와 한림 풍력 단지에 설치되는 HVDC 기기들의 최소 절연거리를 IEC 규격에 맞게 설계하였다. AC/DC 기기의 특정 전압 등급에 견딜 수 있는 최소 거리는 실제 시스템 설치 시 반영함으로써 검증하였다.

• Proceedings of the KIPE Conference
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• 2005.07a
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• pp.449-451
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• 2005

In this paper, to report the experimental results the core losses of VRM inductor. The VRM, that has a output voltage 1.5V, output current 60A, maximum power of 90W. Experimental results verify, the VRM has a almost same data of fast transient response, a efficiency test with high flux and ferrite inductor. A maximum power conversion efficiency of the experimental VRM was measured at 92% within 0.2% load regulation.