• 한국초전도저온공학회:학술대회논문집
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• 한국초전도저온공학회 2003년도 추계학술대회 논문집
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• pp.69-71
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• 2003

The magnetic field sensor was fabricated with superconducting ceramics of YBaCuO system. The sensor at liquid nitrogen temperature showed the increase of electrical resistance by applying magnetic field. Actually the voltage drop across the sensor was changed from zero to a value more than 100 $mutextrm{V}$ by the applied magnetic field. The change in electrical resistance depended on magnetic field. The sensitivity of this sensor was 2.9 $\Omega$/T. The sensing limit was about $1.5\times$10$^{-5}$. The increase of electrical resistance by the magnetic field was ascribed to a modification of the Josephson junctions due to the penetrating magnetic flux into the superconducting material. Considering the observed properties of the superconductor with trapped magnetic flux, a magnetic sensor was fabricated to detect simultaneously both the intensity and the direction of the magnetic field.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 춘계학술대회 논문집 센서 박막재료 반도체 세라믹
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• pp.61-65
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• 2003

A magnetic field sensor is fabricated with superconducting ceramics system The prepared material shows the superconductivity at about 95K. The sensor at liquid nitrogen temperature shows the increase in electrical resistance by applying magnetic field. Actually, the voltage drop across the sensor is changed from zero to a value more than $100{\mu}V$ by the applied magnetic field. The change in electrical resistance depends on magnetic field. The sensitivity of this sensor is 2.9 ohm/T. The increase in electrical resistance by the magnetic field is ascribed to a modification of the Josephson junctions due to the penetrating magnetic flux into the superconducting material.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.1
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• pp.115-118
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• 2003

The sensor at liquid nitrogen temperature showed the increase of electrical resistance by applying magnetic field. Actually, the voltage drop across the sensor was changed from zero to a value more than $100\;{\mu}V$ by the applied magnetic field. The change of electrical resistance depended on magnetic field. The sensitivity of this sensor was $2.9\;{\Omega}/T$. The sensing limit was about $1.5{\times}10^{-5}\;T$. The increase of electrical resistance by the magnetic field was ascribed to a modification of the Josephson junctions due to the penetrating magnetic flux into the superconducting material. Considering the observed properties of the superconductor with trapped magnetic flux, a magnetic sensor was fabricated to detect simultaneously both the intensity and the direction of the magnetic field.

• Journal of the Optical Society of Korea
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• 제19권6호
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• pp.575-585
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• 2015

Magnetic field in magnetic bearings is the physical medium to realize magnetic levitation, the distribution of the magnetic field determines the operating performance of magnetic bearings. In this paper, a thin-slice Fiber Bragg Grating-Giant Magnetostrictive Material magnetic sensor used for the air gap of magnetic bearings was proposed and tested in the condition of dynamic magnetic field. The static property of the sensor was calibrated and a polynomial curve was fitted to describe the performance of the sensor. Measurement of dynamic magnetic field with different frequencies in magnetic bearings was implemented. Comparing with the finite element simulations, the results showed the DC component of the magnetic field was detected by the sensor and error was less than 5.87%.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 추계학술대회 논문집 Vol.16
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• pp.252-254
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• 2003

A magnetic field sensor is fabricated with superconducting ceramics system. The sensor at liquid nitrogen temperature shows the increase in electrical resistance by applying magnetic field. Actually, the voltage drop across the sensor is changed from zero to a value more than $100{\mu}V$ by the applied magnetic field. The change in electrical resistance depends on magnetic field. The sensitivity of this sensor is 2.9 ohm/T. The increase in electrical resistance by the magnetic field is ascribed to a modification of the Josephson junctions due to the penetrating magnetic flux into the superconducting material.

• Smart Structures and Systems
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• 제6권9호
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• pp.1007-1023
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• 2010

This paper describes the development and evaluation of an innovative TDR distributed moisture sensor. This sensor features advantages of being responsive to the spatial variations of the soil moisture content. The geometry design of the sensor makes it rugged for field installation. Good linear calibration is obtained between the sensor measured dielectric constant and soil physical properties. Simulations by the finite element method (FEM) are conducted to assist the design of this sensor and to determine the effective sampling range. Compared with conventional types of moisture sensor, which only makes point measurement, this sensor possesses distributed moisture sensing capability. This new sensor is not only easy to install, but also measures moisture distribution with much lower cost. This new sensor holds promise to significantly improve the current field instruments. It will be a useful tool to help study the influence of a variety of moisture-related phenomena on infrastructure performance.

• 한국통신학회논문지
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• 제40권2호
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• pp.349-354
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• 2015

본 논문은 차량감지를 위해 자기센서를 이용하여 자기신호를 측정하고 형상을 분석한 결과에 관한 것이다. 자기센서는 하니웰사의 MR센서를 이용하였고, 센서의 성능을 알아보기 위해 3축의 길이가 1.2 m인 자기장 발생장치를 제작하여 자기장 감지능력을 측정하였다. 차량감지는 주행차로와 비 주행차로에 센서를 설치한 후 감지여부와 차체의 크기가 다른 7개 차량에 대해서 자기장을 측정하였다. 또한 SUV와 소형 차량의 주차구역과 비 주차구역에 센서를 설치하고 자기장 형상을 분석하였다. 마지막으로 차량의 각 부분별 자기장 형상을 측정하였다. 측정 결과 주행차로에 자기장 형상은 비 주행차로의 경우보다 자기장 첨두치가 크며 복잡한 형상을 보여 센서의 설치 위치로 주행차로와 주행차의 방향을 구분할 수 있었으며, 차체가 클수록 자기장의 변화가 커서 차량 종류를 식별할 수 있었다. 또한 차량의 각 부분별 자기장의 변화를 측정하여 형상을 분석하였다.

• Current Optics and Photonics
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• 제6권2호
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• pp.183-190
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• 2022

Based on the linear electro-optic (EO) effect of lithium niobite (LiNbO₃, LN) crystal, an intense two-dimensional (2D) electric field sensor was analyzed, fabricated and experimentally demonstrated. The linear polarized light beam transmits along the optical axis (z-axis) of the LN crystal, and the polarization direction of the polarized light is 45° to the y-axis. The sensor can detect the intensity of a 2D electric field that is perpendicular to the z-axis. Experimental results demonstrated that the minimum detectable electric field of the sensor is 10.5 kV/m. The maximum detected electric field of the sensor is larger than 178.9 kV/m. The sensitivity of the sensor is 0.444 mV/(kV·m^-1). The variation of the sensitivity is within ±0.16 dB when the sensor is rotated around a z-axis from 0° to 360°. The variation of the sensor output optical power is within ±1.4 dB during temperature change from 19 ℃ to 26 ℃ in a day (from 7:00 AM to 23:00 PM) and temperature change from 0 ℃ to 40 ℃ in a controllable temperature chamber. All theoretical and experimental results revealed that the fabricated sensor provides technology for the direct detection of intense 2D electric fields.

• 한국초전도저온공학회:학술대회논문집
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• 한국초전도저온공학회 2000년도 KIASC Conference 2000 / 2000년도 학술대회 논문집
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• pp.109-111
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• 2000

A magnetic field sensor is fabricated with superconducting ceramics of Y-Ba-Cu-O system. The prepared material shows the superconductivity at about 95K. The sensor at liquid nitrogen temperature shows the increase in electrical resistance by applying magnetic field. Actually, the voltage drop across the sensor is changed from zero to a value more than 100$\mu$V by the applied magnetic field. The change in electrical resistance depends on magnetic field. The sensitivity of this sensor is 2.9 ohm/T. The sensing limit is about $1.5\times$$10^{-5}$ (=1.5$\times$$10^{-1}$ G). The increase in electrical resistance by the magnetic field is ascribed to a modification of the Josephson junctions due to the penetrating magnetic flux into the superconducting material.

• 한국전기전자재료학회논문지
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• 제14권6호
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• pp.491-498
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• 2001

The relationship between electrical properties of YBaCuO superconductor and externally applied magnetic field was studied to develop a magnetic field apolarity sensor. The electrical resistance of the superconductor was increased by applying external magnetic field and even after removal of the magnetic field. The behavior was related to the magnetic flux trapped in the superconductor, which penetrates through the materials by the external magnetic field. Some portion of the superconductor was changed to a normal state by the trapped magnetic flux. The appearance of the normal state yielded to enhance the electrical resistance. 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. Considering the observed properties of the superconductor with trapped magnetic flux, a magnetic sensor was fabricated to detect simultaneously both the intensity and the direction of the magnetic field.