• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 기술교육위원회 창립총회 및 학술대회 의료기기전시회
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• pp.43-46
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• 2001

The DC dielectric breakdown of epoxy composites used for transformer was experimented and then its data were simulated by Weibull distribution equation in this study. The more hardener increased the stronger breakdown strength at low temperature because of cross-linked density by the virtue of ester radical, and the breakdown strength of specimens with filler was lower than it of non-filler specimens because it was believed that the adding filler formed interface, charges were accumulated in it, the molecular mobility was raised, the electric field was concentrated, electrons were accelerated and then electron avalanche was early accomplished. From the analysis of Wei bull distribution equation, it was confirmed that as the allowed breakdown probability was· given by 0.1[%], the value of 'applied field was needed to be under 17.20[kV/mm].

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 춘계학술대회 논문집 기술교육전문연구회
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• pp.159-163
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• 2003

In this study, the DC dielectric breakdown of epoxy composites used for PCB material was experimented and then its data were simulated by Weibull distribution equation. The more hardener increased the stronger breakdown strength at low temperature because of cross-linked density by the virtue of ester radical, and the breakdown strength of specimens with filler was lower than it of non-filler specimens because it is believed that the adding filler forms interface and charge is accumulated in it, therefore the molecular motility is raised, the electric field is concentrated, and the acceleration of electron and the growth of electron avalanche are early accomplished. From the analysis of Weibull distribution, it was confirmed that as the allowed breakdown probability was given by 0.1[%], the applied field value needed to be under 21.5[kV/mm].

• 한국전자파학회논문지
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• 제22권1호
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• pp.38-46
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• 2011

본 논문에서는 아날로그 및 디지털 TV 수신기의 만족스러운 서비스 품질을 보장하기 위해 요구하는 서비스 거리를 계산하는 방법론을 제안하였다. ITU-R 권고 P.1546에 근거한 TV 수신기의 전계 강도 수식을 이용하여 두 TV 시스템에 대한 수치 계산 결과를 제시하고 고찰하였다. 또한, ATV에서 DTV 전환에 따라 만족해야 하는 동등한 수준의 서비스 관점에서 시스템의 중요한 변수에 대해서도 고찰하였다. 제시된 방법은 전송 품질의 만족 여부를 확인하기 위한 수신 지역의 전계 강도 예측 값을 제공할 뿐만 아니라 동일 및 인접 채널로부터 보호비 또는 이격 거리 도출에도 적용될 수 있다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
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• pp.900-903
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• 2002

Partial discharges(PD) in air, corona discharges, deteriorate the insulation strength. So, it is necessary to detect PD at an early stage before the system failure and extensive damage to the equipment. PD emit signals which can be detected by applying an capacitive electric field diagnosis. In this paper, We measured signals by capacitive electric field sensor and analyzed FFT from PD, and then compared conventional electric PD detecting method to capacitive electric field diagnosis by $\Psi-q-n$, $\Psi-v-n$, $\Psi-n$, $\Psi-q$ distributions.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집 Vol.14 No.1
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• pp.601-604
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• 2001

The insulation materials of cables used for underground power transmission requires a higher insulating capability. and the most popular method to examine the cable is partial discharge test due to applying variation voltage. In the thesis. air void. silicone oil. of which may possibly exist real cables. are simulated by Electra 2D program. Also the relations between calculated field strength and the void defect type in the cable joint materails. In the modeling. electic field inner to the cable joint material composed by XLPE and EPDM is modeling simulated. We obtained the electric field distribution in void due to two conditions.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 춘계학술대회 논문집 초전도 자성체 연구회
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• pp.101-104
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• 2003

The maximum coercive force of SmCo thin film was obtained at the Sm=28.2% and dc bias field was generated to CoZrNb, soft magnetic thin film, deposited on the SmCo thin film. DC field point having the maximum permeability for CoZrNb was shifted to higher dc field. DC field strength increased as the length of easy direction of magnetization decreased and 60Oe was measured for $3mm{\times}0.5mm$ sample.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집
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• pp.601-604
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• 2001

The insulation materials of cables used for underground power transmission requires a higher insulating capability, and the most popular method to examine the cable is partial discharge test due to applying variation voltage. In the thesis, air void, silicone oil, of which may possibly exist real cables, are simulated by Electro 2D program. Also the relations between calculated field strength and the void defect type in the cable joint materials. In the modeling, eclectic field inner to the cable joint material composed by XLPE and EPDM is modeling simulated. We obtained the electric field distribution in void due to two conditions.

• 한국전자통신학회논문지
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• 제14권3호
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• pp.613-618
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• 2019

EMF (전자기장)는 지식 기반 정보 사회에서 살기위한 귀중한 자원 중 하나다. EMF는 우리의 삶을 쉽고 편리하게 만들어주는 가전제품과 휴대 전화, 개인용 컴퓨터, 의료 기기 및 방송 타워 등의 정보 통신 기기에 사용된다. 그러나 EMF 노출과 관련된 생물학적 유해성은 전기 통신 장치로부터의 신호도 증가하고 있다. 인체에 대한 EMF 노출의 영향에 대한 연구가 오랫동안 수행되었지만 EMF 효과가 유해한 지 여부는 아직 증명되지 않았다. 본 논문에서는 생활주변의 각종 전자기기로부터 방출 되는 전자장과 그 영향에 대해서 고찰한다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 춘계학술대회 논문집 센서 박막재료연구회 및 광주 전남지부
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• pp.50-53
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• 2008

In this work, the $TiO_2$ pigment influence in HDPE dielectric strength was analyzed. Chemical and structural characterizations were made to identify changes during the processing and your influence in the electrical properties. Formulations containing 0, 0.5, 1, 2.5, 4 and 6 of titanium dioxide were processed by extrusion and injection molding with stabilization-antioxidants, ultraviolet stabilizers and plasticizers. The electrical strength tests were analyzed by the statistical distribution of Weibull, and the maximum likelihood method. The high concentrations present lower values to electrical strength. The $\beta$ parameter could be using to insulator particles dispersion. The $TiO_2$ concentration variation shows that these incorporations implicate strength values increase has a maximum (5,35MV/cm). High pigment concentration induces a little falls in property values. Observing the $\beta$ parameter, minimum experiment electric field (Ebmin) and electric strength value, found that the best electric perform formulation was the formulation with 2.5% $TiO_2$ weight.

• 한국전기전자재료학회논문지
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• 제26권10호
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• pp.726-730
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• 2013

In order to develop a high voltage insulation material, spherical silicas with two average particle sizes of 5 ${\mu}m$ and 20 ${\mu}m$ were mixed in different mixing ratios (1:0, 0.7:0.3, 0.5:0.5, 0.3:0.7, 0:1) and their total filling content was fixed at 65 wt%. In order to observe the dispersion of the spherical silicas and the interfacial morphology between silica and epoxy matrix, field emission scanning electron microscope (FE-SEM) was used. The electrical insulation breakdown strength was estimated in sphere-plate electrodes with different insulation thicknesses of 1, 2, and 3 mm. Electrical insulation breakdown strength decreased with increasing mixing ratio of 5/20 ${\mu}m$ and the thickness dependence of the breakdown strength was also observed. The tensile strength of the neat epoxy was 82.8 MPa as average value and its increased with decreasing particles size and that of epoxy/silica (2 ${\mu}m$) was 107 MPa, which was 130.8% higher value.