• Journal of Power Electronics
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• 제19권4호
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• pp.980-988
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• 2019

When compared with traditional power frequency generators, the frequency of a super high-speed permanent magnet generator (SHSPMG) is a lot higher. In order to study the influence of frequency on the electromagnetic field of SHSPMGs, a 60000rpm, 117kW SHSPMG was taken as a research object. The two-dimensional finite element model of the generator was established, and the two-dimensional transient field of the generator was simulated. In addition, a test platform of the generator was set up and tested. The reliability of the simulation was verified by comparing the experiment data with that of the simulation. Then the generator electromagnetic field under different frequencies was studied, and the influence mechanism of frequency on the generator electromagnetic field was revealed. The generator loss, voltage regulation rate, torque and torque ripple were analyzed under the rated active power load and different frequencies. The influences of frequency on the eddy current density, loss, voltage regulation rate and torque ripple of the generator were obtained. These conclusions can provide some reference for the design and optimization of SHSPMGs.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 C
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• pp.1670-1672
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• 2001

In compared with air insulated switchgear GIS has a high efficiency and confidence. Insulation method using $SF_6$ gas has a very excellent insulation characteristics for high voltage equipment but has a characteristics that insulation heredity is changed for internal unequal electric field. So analysis of electromagnetic field in GIS is very important basic data for structure design and trouble diagnosis process. In compared with established method, SNM in this paper observes variation of the electromagnetic field with real time and get result very similar to measurement. In order to know the variation of electromagnetic field distribution for transient response for time and position, variations are observed when metal particles are moving fast.

• 한국진공학회지
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• 제17권5호
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• pp.400-407
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• 2008

본 연구에서는 축전 결합형 플라즈마원에 대한 전자기장의 2차원 공간 의존성을 계산하였다. 1차원 유체 방정식을 기반으로 축전 전기장과 전도 전류 밀도의 axial 방향 공간 의존성을 계산한 후, radial 방향으로는 맥스웰 방정식의 해를 ${\omega}r/c$에 대한 power series로 전개하여 전자기장의 2차원 공간 의존성을 계산하였다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2018년도 춘계 학술논문 발표대회
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• pp.4-5
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• 2018

Recently, high-strength concrete used for shortening the construction time of high-rise building construction, Concrete pumping technology is emerging as the core technology of high-rise buildings. In this paper, we have started to study the use of electromagnetic field as a method to increase the efficiency of the lubricating layer between the inside of the pipe and concrete, which has been established as the most important factor determining the pumping performance. The pumping performance improvement effect of concrete strength was verified and basic research was carried out to utilize it as a method to increase the efficiency of pumping in field application. In the related work, the effect of the electromagnetic field was verified by conducting a mock-up performance evaluation (horizontal 300 m) of the pumping force by the concrete strength.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제51권2호
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• pp.68-73
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• 2002

In compared with air insulated switchgear, GIS has a high efficiency and confidence. Insulation method using $SF_6$ gas has a very excellent insulation characteristic for high voltage equipment but has a characteristic that insulation heredity is changed for internal unequal electric field. So analysis of time varying electromagnetic field in GIS is very important for structure design and trouble diagnosis process. In compared with established method, the SNM(Spatial Network Method) in this Paper can observe variation of electromagnetic field with real time and get result very similar to measurement. In order to Know variation of electromagnetic field distribution in fast moving particle, we make used of SNM.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2009년도 춘계학술대회 논문집 특별세미나,특별/일반세션
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• pp.403-406
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• 2009

Recently, electricity is essential for human lives. Modem people take cultural benefits due to the development of the electric power system and the spread of the high tech-electric appliances, the cell phones, and etc. However, the electromagnetic field problems become prominent figures owing to the fault of the communication devices around the power line and the biological effect, and etc. In this paper, we introduce the simple electromagnetic field calculation based on the transmission line matrix method, prior to the analysis about the influence of electromagnetic field. Simulation object is the inner part of the trailer car in the high speed train. Unlike the existing paper we submitted, we analyze not only the magnetic field but the electric field in the inner part of the trailer car which makes up the high speed train.

• 반도체디스플레이기술학회지
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• 제20권3호
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• pp.83-86
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• 2021

In this paper, electric fields in electromagnetic reverberation chambers, which are used as a substitute facility for EM-free anechoic chambers, are analyzed. This paper focused on the 4-5 GHz band, which is expected to adversely affect equipment. To analyze the field uniformity inside the electromagnetic reverberation chamber, electric field strengths are sampled and finite-difference time-domain method was used for numerical analysis. Moreover, Quadratic residue diffuser was used to improve the characteristics of the electromagnetic reverberation chamber and the uniformity of the internal field strength. Standard deviation, tolerance characteristics, and partiality characteristics were compared while varying the aiming point of transmission antenna.

• 한국전자파학회논문지
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• 제11권5호
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• pp.839-848
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• 2000

본 논문은 전자파 장해 및 복사내성 측정에 사용되는 전자파 무반사실의 대용 방법으로 활용될 수 있는 전자파 잔향실의 전자기장 특성에 관하여 연구하였다. 체적이 동일한 직사각형 및 삼각형 구조의 잔향실 내부 필드균일성을 확보하기 위하여 Shroeder diffuser 방식을 적용하였으며, FDTD(Finite-Difference Time-Domain) 방법을 사용하여 잔향실 내부의 필드 특성을 조사하였다. 앞에서 언급한 두 가지 형태의 잔향실 내부에서 필드 특성을 조사하기 위해 시험공간 내의 75% 샘플을 가지고 분석하였다. 직사각형 잔향실의 경우 최대 $\pm$3dB, 삼각형 잔향실의 경우 최대 $\pm$4.4dB 내의 tolerance를 나타내었으며, 또한 직사각형 잔향실의 경우 편파에 대해서도 독립적이라는 결과를 얻을 수 있었다.

• 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.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 추계 학술발표회 제16권2호
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• pp.141-144
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• 2004

Nowadays, there has been substantial interest in whether there is an association between electromagnetic field exposure and living environment. It is increased the demand that electromagnetic wave environment and its countermeasure. In the present study, we has applied the electromagnetic absorbent inorganic paint of 'I' corporations, and measured electromagnetic waves generated in new apartment before occupancy using the standard field electromagnetic wave generating device we developed. The measurement before occupancy was $100\~131V/m$, but the measurement after occupancy was $6.9\~8.0V/m$ less than 10V/m, the comprehensive electromagnetic wave limit allowed by TCO in Sweden. The implication is that domestic apartment are exposed to extremely poor electromagnetic wave environment. Nevertheless, there have been neither serious efforts to overcome this problem, nor its alternatives and related standards. Therefore, it is necessary to continue research of related fields to establish standards and plans to improve the situation.