• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.168.2-168.2
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• 2013

테슬라 코일은 니콜라 테슬라가 고안한 변압기로, 교류 아크 방전을 통한 플라즈마의 발생을 관찰할 수 있는 기기이다. 고전압 트랜스를 사용해 저전압을 고전압으로 변환하고, 변환된 에너지를 콘덴서에 충전시켜 스파크 갭 사이에 절연파괴를 일으켜 아크 방전을 통한 플라즈마를 발생시킨다. 이 때 콘덴서와 1차코일 사이에 폐회로가 형성되고, 1차 코일과 2차 코일 사이에 전자기장이 생긴다. 공진주파수가 맞을 때 만들어진 전자기장으로 에너지가 전달되고, 2차 코일에서 증폭된 에너지는 충전된 탑로드 끝에서 아크 방전을 통하여 플라즈마의 형태로 방출된다. 본 프레젠테이션에서는 한동글로벌 학교 고등학생들이 50시간에 걸쳐 직접 제작한 테슬라 코일의 자세한 스펙, 만든 부품들과 그를 만드는 데 사용한 물품들, 설계도들, 날짜별로 기록한 테슬라 코일의 자세한 제작 과정과 후기, 만든 테슬라 코일의 작동과 이를 이용한 추가적인 실험 내용을 발표하고자 한다.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2020.10a
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• pp.134-134
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• 2020

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 1999.07a
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• pp.11-44
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• 1999

1996년, 한국전자파학회 내에 <전자장과 생체 관계 연구회>가 조직된 이후, 3년 동 안의 연구를 한 결과, 생활 주변 및 고전자기장 지역의 전자장 환경을 파악하였으며, 여러 국가 또는 국제 안전기준들을 검토한 후, 한국 실정에 적합한 노출 안전기준과 환경측정기 준을 작성하게 되었다. 본 발표에서는, 연구회가 3년을 거쳐 전자기장 노출에 대한 안전기준 및 측정기준을 제안 하게 된 과정과 , 안전 기준 제정 작업과 관련된 과거의 일정 및 노출 안전기준의 법제화와 관련된 향후의 일정들을 소개한다.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2000.04a
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• pp.105-108
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• 2000

• Electrical & Electronic Materials
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• v.21 no.1
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• pp.11-20
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• 2008

EL (Electro-Luminescence)란 전계발광소자로서 반도체, 주로 형광체에 전계를 인가할 때 아무런 열 발생 없이 발광하는 현상을 말한다. EL 발광현상은 형광물질에 고전기 장이 인가되었을 때, 고전기장에 의해 전자를 가속되고 가속된 전자가 발광중심이라 불리는 Light-emitting Center의 전자를 충돌 여기 시키고 이렇게 여기 된 전자가 다시 바닥상태로 완화될 때, 빛이 발생하는 현상을 일컫는다. 이러한 효과를 이용하여 여러 가지 디바이스에 응용이 되고 있고, 특히 TN, STN LCD의 백라이트로서 각광을 받았으나, 휴대폰 LCD의 컬러화로 인해 그 수요가 급격히 감소하였으나, 현재는 휴대폰의 키패드의 백 라이트로서 LED와 경쟁을 하고 있다. EL만이 가지는 여러 가지 장점으로 인해 광고용 등에 특히 많이 응용이 되고 있다. 또한 캐나다의 iFire사(社)와 같은 회사에서는 무기 EL을 이용하여 디스플레이로서도 활용을 하고 있어 그 응용 가능성이 매우 크다.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2002.10a
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• pp.288-291
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• 2002

The carbon fiber or glass fiber reinforced prepregs were manufactured using electrostatic flocking technology. The powder of high density polyethylene was used as a matrix. The base film of polyethylene was prepared using a fluidized bed of polyethylene powder under the high electric field. We obtained HDPE film with uniform thickness of minimum $80\mu\textrm{m}$. And the fibers were aligned on the molten HDPE film by the electroflocking process. The short fibers with 1mm were easily electrically charged and aligned under the high electric field. The carbon fibers with high conductivity were elasily electrically charged than the glass fibers with low conductivity. So lower electric field was needed for the carbon fibers.

• Polymer(Korea)
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• v.24 no.2
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• pp.268-275
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• 2000

We investigated the effect of polymer sublayer on volumetric resistivity and tensile strength of carbon fiber (CF)/polyethylene composite films fabricated under high intensity electric fields. The dependence of volumetric resistivity and tensile strength of the films on the polymer sublayer thickness or mass part exhibited complex behavior according to CF content and CF layer density in the films. As the thickness of polymer sublayer increases, two groups of processes at thermo-mechanical forming stage would take effects in the properties of the films. The first group comprises the increase of polymer layer thickness having reduced CF content compared with central or upper part of the film and insufficient wetting of CF resulting in the loosened structure near upper film side. The second group, on the other hand, is the improvement of mobility of molten sublayer leading to better distribution of CF throughout the film thickness and the formation of more compact structure. The different degree of contribution of these two competing processes at varied CF content and CF layer density could explain complex dependence of the film properties on the polymer sublayer. These results are important to optimize the electrical and mechanical properties of highly conductive polymer films, which can be used as electromagnetic interference shielding materials.

• Polymer(Korea)
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• v.25 no.2
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• pp.293-301
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• 2001

Electrically conductive carbon fiber/high density polyethylene (CF/HDPE) composite films were fabricated by new method, so called electron-ion technology (EIT) and the effects of CF epoxy sizing on the volumetric resistivity. tensile strength and interphase properties of the films were investigated. While epoxy sizing increased conductivity of composite films resulting from enhanced tunneling effect it reduced interphase adhesion between CF and HDPE because polar epoxy sizing and nonpolar HDPE are incompatible. Consequently epoxy sized CF(CF(S)) caused significant reduction in the volumetric resisitivity and tensile strength of composite films when compared with unsized CF(CF(U)). Epoxy sizing reduced nucleating efficiency of CF(S), therefore CF(S)/HDPE composite films showed nonuniform transcrystalline layer when compared with CF(U)/HDPE composite films.

• Food Science and Preservation
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• v.14 no.2
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• pp.165-169
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• 2007

High voltage pulsed electric fields (PEF) is a promising technology for the nonthermal extraction of effective components from biological materials. Plant cells were ruptured with PEF at ambient or refrigerated temperature for a short treatment time of second or microsecond. Treatments of coarsely ground purple sweet potato (PSP) with PEF(30 kV/cm, 500 Hz) resulted in maximum extraction yield of 65% as compared with 45-50% for control. An increase in electric field strength (from 10kV/cm to 35kV/cm) and frequency (from 100Hz to 500Hz) resulted in increased amount of extracted pigments, but treatment time is not affected on pigment extraction. Starch granules were not detected and large intracellular spaces were visible between the cells on light and scanning election microscopy of PEF treated PSP. This result suggests that PEF have potential to use on extraction of pigments from plant cells.

• Journal of the Korean Vacuum Society
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• v.18 no.3
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• pp.176-185
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• 2009

The realization and the performance of ICP source are strongly affected by its electrical impedance and the electric/magnetic field distribution. The ICP source impedance is determined by the antenna impedance and the plasma one. It is preferred to keep the imaginary impedance between -100 ohm to 100 ohm, since it should be avoided the high voltage formation on the antenna and abrupt impedance variation during the thin film process. The plasma uniformity is affected by the electric and magnetic field which is formed by the antenna current and voltage. The influence of azimuthal symmetry are shown by the electromagnetic simulation and the measurement result of plasma density. The radial uniformity can be controlled by locating the concentric antennas which have different diameters. The power distribution ratio and its control method are presented in the case of parallel antenna connections.