• Journal of Sensor Science and Technology
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• v.11 no.4
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• pp.247-253
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• 2002

For fabrication of the pyroelectric IR sensor $(Pb,La)TiO_3(PLT)$/$LiTaO_3$/(LTO)/PLT ferroelectric thin films was deposited by rf magnetron sputtering followed by rapid thermal annealing and the crystallinity as a function of annealing temperature and time was investigated. Permittivity and dielectric loss factor of ferroelectric thin films as a function of c-axis preffered orientation was measured. Also pyroelectric coefficient of ferroelectric thin films with largest c-axis preffered orientation was measured and obtain figure of merit of voltage response($F_V$) and detectivity($F_D$). In this case $F_V$, $F_D$ was $5.63{\times}10^{-10}\;C{\cdot}cm/J$, $1.98{\times}10^{-8}\;C{\cdot}cm/J$, respectively.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.11
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• pp.9-17
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• 2002

최근에 초전도 산업과 저온 작동 정밀 센서 기술의 발전으로 극저온 냉동기 또는 극저온 한제에 의해 냉각된 저온 용기의 저온 유지 기술이 필요하게 되었다. 또한 의료용 MRI, 야간 투시경용 적외선 센서, 이동통신무선기지국용 초전도 필터 등과 같이 일반인들도 극저온을 이용하게 되어 보다 사용하기 쉽고 안정적인 저온용기가 요구되고 있다. 저온용기의 저온 유지 기술은 진공 및 복사 단열 기술 뿐만 아니라 극저온 발생기술과 진공 발생 기술이 같이 고려되어야 하는 복합기술로서 앞으로 전자, 정보 통신, 나노, 바이오 산업 등에도 널리 활용될 수 있는 기반 기술로 자리 매김 할 것으로 보여 관련 연구자들의 많은 노력과 관심이 요구된다.

• Proceedings of the Korean Ceranic Society Conference
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• 2003.10a
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• pp.96.2-96
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• 2003

• Electrical & Electronic Materials
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• v.10 no.6
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• pp.589-607
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• 1997

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2003.02a
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• pp.137-139
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• 2003

The relationship between magnetic properties of BiPbSrCaCuO superconductor and externally applied magnetic field was studied to develop a magnetic field polarity sensor. The behavior was related to the magnetic flux trapped in the superconductor, which penetrates through the material by the external magnetic field. Some portion of the superconductor was changed to a normal state by the trapped magnetic flux. Electrical characteristics of the superconductor with trapped magnetic flux were extremely sensitive to the external magnetic field and showed different responses depending on the direction of the magnetic field.

• Journal of the Institute of Electronics and Information Engineers
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• v.54 no.1
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• pp.152-156
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• 2017

Until now, most of the studies related to the ultrasonic sensor was in the water or the air. This study is for ultrasonic sensor in crude oil. because the ultrasonic cell use high voltage, it can cause an explosion. So, in crude oil, it did not use an ultrasonic sensor. This is the study of the ultrasonic sensor that generates ultrasonic waves while preventing explosion. Through this study, when trasmit ultrasonic in the crude oil, it found the most adaptive diameter, thickness, transmit frequency of ultrasonic cell to measure the depth of the crude oil and sludge. In conclusion, when a 200kHz frequency is generated by applying a voltage of 24V to the ultrasonic cell, the optimum diameter of ultrasonic cell is 26~28mm, the thickness of ultrasonic cell is 9mm.

• Journal of the Korean Society for Precision Engineering
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• v.24 no.6
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• pp.37-44
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• 2007

• Proceedings of the Korean Society of Computer Information Conference
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• 2018.07a
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• pp.179-180
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• 2018

자계 검출 센서는 여러 가지 종류가 있으나 벽면에 흐르는 미소 자계 및 차폐 전선에서 검출이 가능한 구조는 초전도 양자 간섭 소자(SQUID)가 주로 사용되지만 가격 및 물성 재료 특성으로 인하여 특수 용도로 사용되고 있다. 이에 본 연구에서는 전선으로부터 발생되는 저주파 자장을 검출할 수 있고 휴대성 및 가격이 저렴한 구조인 코일형 자계측정기를 개발하기 위해 자기 코어 및 코일 Turn수 변화에 따른 자계 검출 감도를 조사하여 최적의 구조를 설정하였다.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.8 no.4
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• pp.667-672
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• 1998

Pyroelectric properties of $Pb(Mg_{1/3}Nb_{2/3})O_3-PbTiO_3$ ceramics prepared by the columbite precursor method have been investigated as a function of the sintering temperature in the range of $1000^{\circ}C$ to $1250^{\circ}C$. The $Pb(Mg_{1/3}Nb_{2/3})O_3-PbTiO_3$ ceramics show typical relaxor ferroelectric behavior. The optimum condition for obtaining samples with high densities and improved pyroelectric properties occur at a sintering temperature of $1250^{\circ}C$ and sintering times of 2 hours. The $Pb(Mg_{1/3}Nb_{2/3}O_3-PbTiO_3$ ceramics show the possibility for pyroelectric sensors with pyrostat.

• Proceedings of the Korean Vacuum Society Conference
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• 1995.06a
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• pp.38-39
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• 1995