• 한국전기전자재료학회논문지
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• 제11권10호
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• pp.773-777
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• 1998

This paper presents the results of measured permittivity of PCB sheet material in the frequency range of 0.1 ~ 2[㎓] and temperature range of 25~ 85[>$^{\circ}C$]. Microstrip lines with different physical length are implemented to measure the attenuation and phase shift of the signals through these lines. The loss factor of glass-epoxy and teflon could by calculated with the measured dielectric constant and the attenuation. From the experiment, the glass-epoxy was more influenced by temperature and frequency than teflon. The average dielectric constants of glass-epoxy and teflon within the measured frequency range are 4.48 and 2.18, respectively.

• 수산해양기술연구
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• 제32권4호
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• pp.457-464
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• 1996

The vibration damping of various multilayer damping sheet with different constraining layer and viscoelastic layer were investigated by Rheovibron and vibration test. Damping increased as dynamic loss tangent increased. Constrained type damping sheet showed better damping than extensional type damping sheet. Aluminum foil attached asphalt impregnated paper pad showed best damping.

• 한국초전도학회:학술대회논문집
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• 한국초전도학회 2002년도 High Temperature Superconductivity Vol.XII
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• pp.58-58
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• 2002

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.1453-1456
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• 2009

Transparent sol-gel hybrid dielectric material (hybrimer) coating films were fabricated by spin coating and photo or thermal curing of sol-gel derived oligosiloxane resins. Hybrimer coating films are suitable as the passivation layer of TFT in AMLCD due to low dielectric constant, small loss tangent, low leakage current density, high transmittance and thermal stability.

• Journal of Electrical Engineering and information Science
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• 제2권5호
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• pp.40-44
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• 1997

This paper presents the results of studies made for measuring the relative complex permittivity of PCB sheet material in he frequency a range of 100MHz∼1GHz using vector network analyzer. A measurement cell was developed for this purpose using broad-band impedance method and the dielectric constant and loss tangent of two PCBV sheet materials, glass-epoxy and teflon, were measured. The effect of copper cladding was studied.

• 대한전자공학회논문지TC
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• 제47권11호
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• pp.91-96
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• 2010

본 논문에서는 hook형 패치를 이용한 무선 USB 동글(dongle)용 안테나를 제안한다. 제안된 안테나는 hook형 패치에 모노폴 element를 결합시켜 다중 대역 특성을 구현하였다. 안테나의 전체 크기는 $10mm{\times}50mm{\times}0.8mm$ 이고, 유전율 4.6, loss tangent가 0.025인 FR-4기판 위에 설계되었다. 50옴 동축케이블을 이용하여 급전하였으며, 반사계수 측정 결과 -10 dB를 기준으로, 2.4 GHz - 2.5 GHz, 3.4 GHz - 3.6 GHz, 5.15 GHz - 5.825 GHz 대역에서 공진 특성을 가지는 것을 확인하였다. 또한 측정된 안테나 복사패턴은 전 주파수에서 전방향성 특성을 보였다. 따라서 제안된 안테나는 WLAN, WiMAX, Bluetooth를 대역을 지원하는 소형 무선 USB 동글 장치에 적합할 것으로 사료된다.

• 한국초전도학회:학술대회논문집
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• 한국초전도학회 2000년도 High Temperature Superconductivity Vol.X
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• pp.207-210
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• 2000

Properties of SrTiO$_3$ thin films were characterized under the influence of an applied dc voltage utilizing a gold resonator with a flip-chip capacitor. The measurements were performed at microwave frequency ranges and low temperatures cryogenic temperatures. The dielectric constant of 830 and the low loss tangent of 6X10$^{-3}$ at 3.64 GHz were observed at 90 K and 100 V. The quality in the SrTiO$_3$ film was presented in terms of fractional frequency under the bias voltages and cryogenic temperatures.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 C
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• pp.1428-1430
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• 2002

Polyaniline/polystyrene conducting blends were prepared and measured with the mechanical properties such as tensile strength and elongation and the electrcal properties such as surface resistance, electrical conductivity and dielectric loss tangent. The percolation threshold concentration of blends was 5phr of polyaniline and the morphology of blends was setting colser to that of polyaniline at higher concentration. The dielectric loss increased up to $10^5$ at the 50 % of polyaniline and was much influenced by frequency than temperature at higher concentration of polyaniline.

• 한국화재소방학회논문지
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• 제30권4호
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• pp.94-102
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• 2016

EMP 방호용 차폐 시설을 구축 할 때 소화 배관들의 방호 처리를 위하여 WBC 효과를 이용하며, 차폐도를 높이기 위해서 소화 배관 내부에 허니컴을 삽입한다. 이때 허니컴 단위 셀의 크기가 작으면 물의 흐름에 지장을 주며, 침전물에 의하여 소화 배관이 막히게 된다. 이것을 방지하기 위하여, 물의 분극손실에 의한 차폐도를 이용해서, 허니컴 셀의 크기는 키우고, 두께는 얇게 하면서도 요구하는 차폐도를 얻을 수 있는 설계 방법을 제시하였다.

• 대한전자공학회논문지
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• 제7권2호
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• pp.43-48
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• 1970

마이크로파주파수 대역에서 비자성체의 정밀한 유전상수를 구하는 방법을 서술하였다. 재래식 방법인 공동공진법이나 임피이던스 측정에 의한 방법보다 정밀한 결과를 얻을 수 있었고 간단한 계산식에 대입하여 비교적 적은 오차범위에서 쉽게 결과를 얻을 수 있음을 증명하였다.