• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제55권6호
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• pp.328-333
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• 2006

All the plants on earth live under an electric and magnetic field because the earth is a magnet and there is an electric field between the charged cloud and the ground. It has been reported that electromagnetic fields influence both the activation of ions and polarization of dipoles in living cells of seeds and plants, though the mechanism of these actions is still poorly understood. In this paper, the effects of the electric and magnetic fields and exposure times to the germination of several vegetable seeds and its early growth have been investigated experimentally to find out the feasibility of a plant factory for mass production of clean and unpolluted vegetables. The germination rate and the growth rate of some seeds under the fields exposed were analysed and compared with those of unexposed ones. It is found that the germination rate and its early growth rate of exposed seeds under the fields were accelerated about 1.1-1.4 and 1.7-2.2 times in maximum compared with those of unexposed ones. But, however, an inhibitory effect on germination and plant early growth were shown in the case of the higher electric and magnetic fields.

• JSTS:Journal of Semiconductor Technology and Science
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• 제16권6호
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• pp.867-872
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• 2016

We have investigated the channel mobility of AlGaN/GaN-on-Si recessed-metal-oxide-semiconductor-heterojunction field-effect transistors (recessed-MOS-HFET) with $SiO_2$ gate oxide. Both field-effect mobility and effective mobility for the recessed-MOS channel region were extracted as a function of the effective transverse electric field. The maximum field effect mobility was $380cm^2/V{\cdot}s$ near the threshold voltage. The effective channel mobility at the on-state bias condition was $115cm^2/V{\cdot}s$ at which the effective transverse electric field was 340 kV/cm. The influence of the recessed-MOS region on the overall channel mobility of AlGaN/GaN recessed-MOS-HFETs was also investigated.

• 한국광학회지
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• 제10권6호
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• pp.494-499
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• 1999

전기적으로 굴절율 변조값을 조절할 수 있는 부피형 홀로그램 매질(HPDLC)을 제작하였다. HPDLC는 4가 acrylate monomer를 기초로 한 전폴리머(prepolymer)와 액정 혼합물 E7 등으로 구성되어져 있다. 제작된 매질의 광학적 특성을 조사하기 위해 액정 농도, 전기장의 세기에 따른 회전효율을 측정하고, 홀로그래피 방법으로 상을 기록한 후 재생된 상을 전기적으로 조절할 수 있음을 보였다.

• 대한전기학회논문지
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• 제39권5호
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• pp.508-515
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• 1990

This paper describes the corona characteristics of conductor bundle for EHV transmission line. To reduce the corona noise, the asymmetric conductor bundle to minimize the electric field of the conductor surface is proposed. The charge simulation method is used to formulate the electric field of conductor surface and the optimal arrangement of subconductor to minimize it is selected to apply the nonlinear successive quadratic programming. Through the analytical comparison and the corona cage test, it is proved that the asymmetric conductor bundle proposed in this paper can reduce the average maximum electric field of the phase conductors and the corona noise more than the conventional symmetric conductor bundle and asymmetric conductor bundle by GE.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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• pp.396-399
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• 2008

In this study, the electric field distributions have been investigated by simulation in accordance with the various shapes of ITO-electrodes. Also we have measured the density of excited Xe atoms in the 1s5 state in discharge cell, where the gap distance of 60 um, gas pressure of 400 Torr, Xe contents of 7%, and sustaining voltage of 200 V are kept in this experiment. The maximum density of excited Xe atoms in the 1s5 state in a discharge cell for the fish-boned, T shaped and squared ITO electrodes have been measured to be $3.01\;{\times}\;10^{13}\;cm^{-3}$, $2.66\;{\times}\;10^{13}\;cm^{-3}$ and $2.06\;{\times}\;10^{13}\;cm^{-3}$, respectively. It is shown that the electric field distribution with different ITO Electrodes is essential factor for these maximum density of excited Xe atoms in discharge cell.

• 폴리머
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• 제30권6호
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• pp.568-571
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• 2006

Poly(vinyl alcohol) (PVA)/gelatin(GEL) 블렌드막을 고전장하에서 제조한 후, 팽윤거동 및 이온투과 특성을 연구하였다. 알칼리 금속염(LiCl, NaCl, KCl)에 대한 투과 실험 결과, 인가된 전장의 강도가 10 kV까지 증가하면 막의 곡로율이 감소하여 이온 투과도가 증가하지만, 10 kV이상이 되면 막의 결정화도의 증가 영향이 커져 투과도는 감소하였다. 완충용액에 대한 팽윤 실험에서 pH 6을 기점으로 산성영역 혹은 염기성 영역으로 갈수록 하전기간의 반발로 인하여 팽윤도가 증가함을 관찰하였다. 제조된 블렌드막의 KCl 투과도 계수는 pH 6에서 극대값을 보였고, 산성 혹은 염기성 영역으로 갈수록 급격히 감소되는 것을 확인하였다. 이러한 거동은 막내 존재하는 관능기들이 해리함에 따라 용해도 증가 영향보다는 Donnan 배제효과가 우세하게 작용하기 때문인 것으로 생각된다. 특히 온도에 따른 투과거동에서 $40^{\circ}C$를 기점으로 KCl 투과도 계수가 약 5배 정도 급격히 증가함을 보여주었다.

• 한국응용과학기술학회지
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• 제35권4호
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• pp.1206-1212
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• 2018

본 연구에서는 강유전성 고분자를 이용하여 제작된 100 nm 이하 두께를 가지는 박막형 커페시터의 측정 주파수에 따른 분극 반전 특성을 측정, 분석하였다. 고정된 박막 두께에 대해, 인가되는 최고 전기장의 세기가 증가할수록 더 높은 항전계에서 분극 반전이 발생되었다. 고정된 최고 전기장에 대해, 박막의 두께에 무관하게 같은 항전계에서 분극 반전이 발생되었다. 모든 측정에서 로그스케일 전기장 및 로그스케일 주파수의 관계에서 약 $0.12{\pm}0.01$의 비례 상수를 보였다. 결과적으로, 강유전체 고분자 커페시터가 40 nm 두께까지는 size effect 없이 일정한 분극 반전 특성을 보였다. 본 연구는 저전압 동작 고분자 메모리 소자의 동작 예측에 유용할 것이므로 저전압에서 동작 가능한 고분자 메모리 소자의 가능성을 보여준다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 하계학술대회 논문집 C
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• pp.1639-1642
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• 1994

The severe conditions such as rated voltage of 800kV, gas pressure of $5kg/cm^2$ and rated lighting impulse withstand voltage of 2400kV were adopted for the design of spacers in the 800kV GIS to give a sufficient design margin. The design criteria on the maximum electric field strength of the center conductor and the insulator surface were established by considering the insulator surface characteristics, electrode area and surface effects in the unequal electric field strength of the given gap. The design parameters such as inter/outer envelope degree, thickness, inter/outer inserts, triple junction gap were determined by calculating the electric field using FLUX-2D program package and by referring to the published papers. The mechanical stress analysis was conducted on the feasible model spacers that showed good electric field distributions to confirm the sufficient mechanical design margin. The 800kV spacer designed as described above is now in the process of manufacturing.

• Journal of Magnetics
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• 제21권1호
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• pp.102-109
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• 2016

In this paper, the theoretical and experimental characteristics of magnetic and electric fields in the vicinity of high voltage lines are investigated. To realize these measurements and calculations, we have developed some equations for two overhead power line configurations of 150 kV (single circuit, double circuit), based on Biot-savart law, image and Maxwell theories, in order to calculate the magnetic and electric fields. The measurements were done to a maximum distance from the tower of 50 m, at a height of 1m from the ground. These experiments take into consideration the real situations of the power lines and associated equipment. The experimental results obtained are near to that of the Biot-Savart theoretical results for a far distance from the tower; and for a distance close to the power line, the results from the image theory are in good agreement with the experimental results.

• 한국안전학회지
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• 제11권3호
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• pp.75-80
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• 1996

This paper presents a study on characteristics and safety for human body in ELF electric and magnetic fields using statistical method. The magnetic fields from a power line can be computed given a knowledge of the currents, voltage and geometry of the line. In this paper, a statistical method for predicting the magnetic fields given the inherent indetermination of the currents is presented. But the electric field is calculated given a knowledge of the voltage and geometry of the line. The effect of unexpected fluctuations in current is modeled by the Monte Carlo simulation. The suggested method is applied to the 345kV and 765kV transmission line system, the result shows that the maximum electric and magnetic field intensity is 6.8627kV/m and 284mG in 345kV system, 2. 5590kV/m and 35mG in 765kV system, respectively.