• Progress in Superconductivity
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• 제3권2호
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• pp.183-187
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• 2002

In this paper we analyzed the electromagnetic behavior of high $-T_{c}$ superconductor under the quench state using finite element method. Poisson equation was used in finite element analysis as a governing equation and was solved using algebra equation using Gallerkin method. We first investigate d the electromagnetic behavior of U-type superconductor. Finally we applied our analysis techniques to 5.5 kVA meander-line superconducting fault current limiters (SFCL) which are currently developed by many power-system researcher in the world. Meshes of 14,600 elements were used in analysis of this SFCL. Analysis results show that the distribution of current density was concentrated to inner curvature in meander-line type-superconductors and maximum current density 14.61 $A/\m^2$ and also maximum Joule heat was 6,420 W/㎥. We concluded that this meander line-type SFCL was not pertinet fur uniform electromagnetic field distribution.n.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 신호처리소사이어티 추계학술대회 논문집
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• pp.549-552
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• 2003

The electrical current generated by heart creates not only electric potential but also a magnetic field. We have observed electrophysiological phenomena of the heart by measuring tangential components of magnetocardiogram(MCG) using 61 channel superconducting quantum interference device(SQUD) system. In this paper, we developed a new analysis method, which is based on the theory of electromagnetic field. We show some differences of the current direction between the normal MCG and the abnormal(ischemic heart disease) MCG.

• 항공우주기술
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• 제2권1호
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• pp.153-163
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• 2003

전자 장비들은 전자파 간섭을 통해 다른 시스템에 영향을 주어서 오작동을 야기할 수도 있고 혹은 다를 시스템에 의해 자신이 오작동을 일으킬 수도 있다. 따라서 전자 장비들은 다른 시스템이 오작동을 일으키지 않는 범위에서 전자파 간섭을 주고 다른 시스템에서 전자파 간섭을 일으켜도 오작동을 일으키지 않도록 설계되어야 한다. 전자 장비들이 이러한 조건을 만족하는지를 확인하기 위해서는 전자파 환경시험을 하여야 한다. 본 논문에서는 KSR-III 김발엔진 구동 시스템에 있는 전자 장비들의 전자파 환경 규격과 시험 절차 및 결과를 소개하고자 한다.

• Journal of Magnetics
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• 제17권1호
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• pp.61-67
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• 2012

The miniaturization of an electrostatic precipitator has become a key element in successfully constructing an efficient electrostatic precipitator because of the limited space allowed for installation in a subway tunnel. Therefore, the miniaturization of the rapping system of the electrostatic precipitator has also become important. This research proposes a resonant-type electromagnetic vibration exciter as a vibrating rapper for an electrostatic precipitator. The compact vibrating rapper removes collected dust from the collecting plates without direct impact on those collecting plates. To characterize the dynamic performance of the electromagnetic vibration exciter, finite element analysis was performed using a commercial electromagnetic analysis program, MAXEWLL. Moreover, we analyzed the resonant frequency of an electrostatic precipitator, to which the electromagnetic vibration exciter was applied, by ANSYS. Also, to measure the acceleration generated by the electromagnetic vibration exciter, we manufactured a prototype of the ESP and electromagnetic vibration exciter and measured its acceleration at the resonant frequency.

• 전기학회논문지
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• 제57권5호
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• pp.821-826
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• 2008

Recently as a progress of electric technology, modern electric systems become more and more complicated. Thus, it is difficult to use a classical method to analyze responses of the systems in complicated electromagnetic environments because there are so many coupling phenomena. The electromagnetic topology (EMT) is a helpful solution to analyze electromagnetic interference / electromagnetic compatibility (EMI/EMC) of the large complex system. In this paper, EMT is applied to analyze an active element. And then to prove the validity of this analysis, a detector circuit including Schottky barrier diode is analyzed by EMT when input power is given directly.

• 대한전기학회논문지:시스템및제어부문D
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• 제55권2호
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• pp.82-89
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• 2006

The electroencephalogram generated by light stimulation in human body of dark adaption state was measured and analyzed in the cases that electromagnetic wave was put in and not put in, respectively. Shieldroom being able to interrupt the light and the electromagnetic wave of outer was constructed, and the experimental system being able to apply any light and any electromagnetic wave was designed. When the electromagnetic wave was applied to body or not, the variation characteristics of each component in the electroencephalogram were i3s follows. The 6 wave was increased and the $\alpha$ wave and the $\beta$ wave were decreased in the case that the electromagnetic wave was applied, and the variation range of the $\Theta$ wave was small. And the influence of electromagnetic wave on human body was that the appearance time of the $\beta$ wave was late, and it moaned that the time of visual recognition was delayed.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2009년도 춘계학술대회 논문집
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• pp.751-752
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• 2009

• 한국안전학회지
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• 제12권2호
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• pp.70-79
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• 1997

This paper presents a study on the fuzzy linguistic variable based approach for safety assessment of human body in ELF electromagnetic field considering power system states. To cope with the demand in modern industry, the power system becomes larger in scale, higher in voltage. The advent of high voltage system has increased the relative importance of field effects. The analysis of ELF electromagnetic field based on Quasi-Static Method is introduced while the power system is included to model the expected and/or unexpected uncertainty caused by the load fluctuation and parameter changes. In order to analyze the power system, Monte Carlo simulation method and contingency analysis method are adopted in normal state and alert state, respectively. In the safety assessment of human body, the approach based on fuzzy linguistic variable is employed to overcome the shortcomings resulting from a crisp set concept. The suggested scheme is applied to a sample system(modified IEEE 14 bus system) to validate the usefulness.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.1464-1467
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• 2005

In this research, we developed a system, which can find the location of vehicle when people park their cars in a big parking lot or large area. People can find their cars readily through this simple device and they can save their time and effort. This is the purpose of this research. Performing this, detection of electromagnetic wave's direction is needed and we used shielding effectiveness of electromagnetic waves for the method of it. An absolute coordinate indicates four directions (E, W, S, N) by using an electronic compass module, and it is needed for the localization. The device can check the received count of the electromagnetic waves coming from all other directions through the system, which is installed in the vehicle. The direction recorded the least received count would be the location of the parked vehicles. We can add on the function of this research by using the same frequency of cars alarm goods. Also, it is useful in the huge indoor parking lot.

• 한국전자파학회지:전자파기술
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• 제6권2호
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• pp.11-18
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• 1995

본 연구는 평판형, 그리드형, 특수형상 등의 페라이트 전파흡스체의 흡수능 측정시스템을 구축하는 데에 목적이 있다. 그러나 30MHz와 같이 낮은 주파수에서 흡수능을 측정하느 것은 대단히 곤란 . 이와같은 문제를 해결하기 위하여 평행평판 스 라인을 사용하여 정재파측정법 및 시간영역법을 제안하였으며, 실제 측정시스템을 구성하요 제안한 측정볍으로 그리드형 페라이트 전자파흡수체의 특성을 측정. 평가하였다.특성을 측정. 평가하였다.