• 한국전자파학회논문지
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• 제23권5호
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• pp.652-659
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• 2012

직사각형 슬릿 개구를 갖는 금속 함체에 수직, 수평 편파를 입사하여 차폐 효과를 연구하였다. 직사각형 슬릿개구의 magnetic polarizability와 금속 함체의 공진 모드를 이론적으로 분석하였고, 이를 바탕으로 시뮬레이션 결과와 측정 결과를 비교 분석하였다. 또한, 함체 내부 프로브의 위치에 따른 차폐 효과 의존성도 분석하였다.

• 한국자기공명학회:학술대회논문집
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• 한국자기공명학회 2002년도 제20회 학술발표회
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• pp.10-10
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• 2002

• 한국자기학회지
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• 제23권2호
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• pp.68-76
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• 2013

자기유도형 기반의 무선전력 전송 기술을 이용한 무선충전 기능이 최근 스마트폰 등에 채용되어 주요한 소비자 편의기능으로 자리잡고 있다. 무선전력전송 모듈은 무선전력 전송효율을 개선하고 휴대폰 주요 회로부에 대한 전자기장 간섭을 억제하기 위하여 전자기장 차폐 소재의 사용이 필수적이다. 본 논문에서는 무선전력 전송모듈용 전자기장 차폐 소재의 역할과 기술에 대해 소개하였다. 이와 함께 향후 확산될 중급 전력(mid-power)과 대전력(high-power)영역의 무선전력 전송 응용분야에서 대응 가능한 차폐 소재의 개발 방향을 정리하였다.

• 한국인터넷방송통신학회논문지
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• 제10권4호
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• pp.121-126
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• 2010

HEMP분야에 대한 연구는 1950년대 이후 미국을 중심으로 핵을 보유한 국가에 의해 주로 국가방위를 목적으로 수천 건의 연구가 집중적으로 이루어졌다. HEMP 방호설비의 핵심은 차폐, 필터링, 접지, 과전압 보호로 구성된다. 이중에서 투자비용이 가장 높은 차폐실 설계에 있어 기존에 나와 있는 이론식을 적용하여 시뮬레이션을 하면 특정 주파수 대역을 제외하고 실제 측정값과 전혀 맞지 않는 모순이 있었다. 본 논문에서는 HEMP 방호용 차폐실의 최적설계를 위해 기존 이론식을 개선하여 실제 측정값과 넓은 주파수 범위에서 잘 일치할 수 있는 이론을 제시하고, 각각의 재료정수에 따라 설계전에 충분하게 시뮬레이션을 거쳐 경제적이고 효과적으로 HEMP 방호용 차폐실을 건설할 수 있도록 하는 시뮬레이터를 개발하였다.

• 한국정밀공학회지
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• 제18권2호
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• pp.177-185
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• 2001

This study shows the process design and forming analysis of permalloy shielding can that support the automobile multi-display parts to indicate the accurate information of car. This study is particularly important, since the strain and thickness of permalloy shielding can is known to affect the magnetic properties such as coercivity and permeability quite thickness of permalloy shielding can is known to affect the magnetic properties such as coercivity and permeability quite sensitively. The objective functions are strain and thickness deviation. The punch radius, die radius and blank holding force are considered as design parameters. Orthogonal array (OA) table and characteristics are applied to neural network (NN) as train data. After training, the optimal and robust condition of design parameters is selected. This study shows the correlation between the design methodology of NN and the statistical design of experiments (DOE) approach.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제49권5호
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• pp.291-296
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• 2000

Recently large size color TV and computer monitor are very popular and a lot techniques are being developed to get a high quality picture on the screen through reducing the convergence error among the red, green and blue beams and achieving a high focusing. One of the techniques is considering the mutual effects of the components of the Brown tube. The magnetic deflection yoke, especially, stands immediately next to the electron gun and generates the leakage magnetic fields at the electron gun which affects the trajectories of the electron beams inside the gun. Hence a shield cup made of thin conducting plate is located at the end of electron gun in order to shield the leakage flux from the deflection yoke. Since the red, green and blue beams are placed unsymmetrically the shielding effects of the shield cup on the beams are not same and eddy current controller, made of thin conducting plate, is auxiliary placed inside the shield cup. In this paper a transient magnetic field analysis algorithm is developed using boundary element method, and applied to the analysis of the shielding effects of the eddy current controller of shield cup in an electron gun.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2017년도 춘계 학술논문 발표대회
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• pp.124-125
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• 2017

In this study, the shielding effectiveness of the Zn-Al arc thermal metal film coated cement-mortar mixed with copper powder by reflection, absorption, multi-reflection loss in 2.25~2.65 GHz was reviewed. By enhancing the mixing ratio of copper powder, the shielding effectiveness by absorption and multi-reflection loss was increased, but shielding rate(%) based on 80 dB showed below 20%. The Zn-Al arc thermal metal film coated on specimen, the shielding rate increased 3.5 times by reflection loss.

• 한국초전도ㆍ저온공학회논문지
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• 제15권3호
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• pp.24-28
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• 2013

Fault current limiting (FCL) cable is a kind of superconducting cable which has a function of limiting the fault current at the fault of power grid. The superconducting cable detours the fault current through its stabilizer to keep the temperature as low as possible. On the other hands, the FCL cable permits the temperature rise within some acceptable limit and the fault current is limited by the consequent increase of the resistance of superconducting cable. This kind of FCL cable is called 'resistive FCL cable' because it uses resistive impedance to limit the fault current. In this paper, we suggest a novel concept of FCL cable, which is named as 'inductive FCL cable'. The inductive FCL cable is similar as the magnetic shielding fault current limiter in its operating mechanism. The magnetic field of superconducting cable is almost perfectly shielded by the induced current at the shielding layer during its normal operation. However, at the fault condition, quench occurs at the shielding layer by the induced current higher than its critical current and the magnetic field is spread out of the shielding layer. It will induce additional inductive impedance to the superconducting cable and the inductive impedance can be increased more by installing some material with high magnetic susceptibility around the superconducting cable. We examined the feasibility of inductive FCL cable with simple elemental experiments. The current limiting performance of inductive FCL cable was estimated considering an arbitrary power grid and its fault condition.

• Journal of Magnetics
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• 제20권4호
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• pp.439-443
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• 2015

A control rod drive mechanism (CRDM) is an electromechanical equipment that provides linear movement for the control rods to control the nuclear reactivity in a nuclear reactor. A rod position indication system (RPIS) detects the control rod's position. To enhance the measurement accuracy of the system, a magnetostrictive type sensor with capability of generating operation limiting signals would be adapted instead of a conventional RPIS for a CRDM. An RPIS was modelled for a numerical analysis with the permanent magnets at the stationary limit positions and magnetic shielding plates with a moving permanent magnet. The performance analysis of the RPIS were conducted, and the results were discussed here.

• 한국자기학회지
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• 제21권3호
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• pp.99-103
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• 2011

본 연구에서는 유한요소해석을 이용하여서 양쪽 끝이 열린 형상을 가진 원통형 3층 자기 실드를 설계하기 위한 해석을 수행하였다. 원통형 자성체의 투자율 범위 $2{\times}10^3\sim1{\times}10^5$에서 자기 차폐율을 검토하였고, 자성체의 길이 및 각 층간의 길이 차에 의한 자기 차폐율의 변화를 해석하였다. 투자율이 $2{\times}10^4$ 이상이고 각 층의 길이가 40 cm, 45 cm, 50 cm인 경우 -60 dB 이상의 자기 차폐율을 얻을 수 있었으며, 이때의 균일 자계 영역은 $10cm{\times}10cm-\phi$ 이상이었다.