• 한국전자파학회지:전자파기술
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• 제6권1호
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• pp.3-9
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• 1995

An isotropic electric-field probe, capable of characterizing and quantifying electromagnetic field, was fabricated. The probe consists of three short dipole antennas, a beam-lead Schottky diode and the high resistive transmission line. In order to get the isotropic response three mutually orthogonal dipoles are configured to form the probe. The probe's short dipole elements allow measurements of electric fields from 300MHz to 2GHz with a flatness of .+-. 2.9dB. The mutually orthogonal dipole configration shows a .+-. 1.2dB deviation in the isotropic response with respect to angle.

• 한국음향학회지
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• 제13권3호
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• pp.41-50
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• 1994

이 연구에서는 3차원 음향 인텐시티를 동시에 측정할 수 있는 프로브를 이용하여 음향 인텐시티를 측정할 때 필연적으로 발생하는 오차를 컴퓨터의 수치계산으로 검토하였다. 이 3차원 음향 인텐시티 프로브는 Suzuki등에 의해 제안된 4개의 마이크로폰으로 구성된 것이고, 수치계산에서는 이상적인 점음원과 유한 크기를 가지는 면음원에 대해서 프로브의 각 축방향 및 임의의 방향에 대한 측정오차를 근거리 음장에서 분석하였다. 그 결과, 점음원의 경우 측정거리가 프로브를 구성하는 마이크로폰 사이의 간격보다 약 2.5배 이상 떨어진 거리에서 오차 1dB 이하의 정밀한 측정을 할 수 있었고, 유한 크기의 면음원의 경우, 면음원의 한 변의 길이가 0.02m이상일 때 근거리 음장의 측정오차가 크게 감소하기 시작하여, 한 변의 길이가 0.2m일 때 측정거리가 마이크로폰 사이의 간격보다 0.67배로 근접하여 측정하여도 1dB 이하의 정밀한 측정이 가능한 것으로 평가되어 이 프로브의 근거리 음장 측정의 유효성이 확인되었다.

• Journal of Electrical Engineering and Technology
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• 제9권1호
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• pp.190-196
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• 2014

In this paper, the characteristics of a defective elliptical aluminum plate are analyzed by three different eddy current testing probes; T/R, T/T, and Impedance probes. The analysis was done by 3D finite element method, and the impedance change of real and imaginary voltage values were analyzed.

• Journal of Magnetics
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• 제18권3호
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• pp.342-347
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• 2013

Local wall thinning in pipelines affects the structural integrity of industries, such as nuclear power plants (NPPs). In the present study, a development of pulsed eddy current (PEC) technology that detects the wall thinning of pipelines covered with insulation is reviewed. The methods and experimental results, which have two kinds of probe with a single and double core, were compared. For this purpose, the single and double core probes having one and two excitation coils have been devised, and the differential probe with two Hall sensors has been fabricated to measure the wall thinning in insulated pipelines. The test sample is a stainless steel having different thickness, laminated by plastic insulation to simulate the pipelines in NPPs. The excitation coils in the probe is driven by a rectangular current pulse, the difference of two Hall sensors has been measured as a resultant PEC signal. The peak value of the detected signal is used to describe the wall thinning. The double core probe has better performance to detect the wall thinning covered with insulation; the single core probe can detect the wall thinning up to an insulation thickness of 18 mm, whereas the double probe can detect up to 25 mm. The results show that the double core PEC probe has the potential to detect the wall thinning in an insulated pipeline of the NPPs.

• 미생물학회지
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• 제26권3호
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• pp.149-154
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• 1988

Japanese Encephalitis Virus(JEV) can be detected conveniently by the use of biotinylated cDNA probe. To prepare biotinylated probe aminoallyl dUTP was first synthesized chemically to reverse transcribe the virial RNA. The allylamine-labeled cDNA was then converted to the biotin-cDNA by the reaction with an activated biotin ester, NHS-ACA-biotin. The JEV genomic RNA was hybridized to the biotinylated cDNA probe on nitrocellulose filter and visualized colorimetrically by streptavidin complexes with alkaline phosphatase polymer. Sensitivity of the detection system was determined by estimating the amount of the JEV genomic RNA through comparison with signals generated from the biotinylated and $^{32/P}$ -labeled probes. It was found that the biotin probe was as sensitive as $^{32/P}$ -cDNA probe which can detect 50pgs of the target RNA.

• 한국전자파학회논문지
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• 제9권3호
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• pp.378-385
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• 1998

본 논문에서는 종단판 프로브와 동조 포스트가 포함된 동축선 대 캐비티 필터의 특성을 3차원의 시간영역 유한차분(3-D FDTD) 방법에 의해서 계산하였다. 이 필터는 캐비티 안으로 삽입된 동축선의 내부도체가 복사체 역학을 하며, 사각혀 ㅇ동조 포스트의 높이에 의해서 공진주파수를 결정하게 되는 구조이다. 이러한 필터 특성의 계산값과 실제 제작된 필터의 측정값을 비교하여 이 해석 방법의 유용성을 확인하였다.

• Journal of electromagnetic engineering and science
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• 제17권1호
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• pp.1-8
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• 2017

This paper introduces a technique to obtain the broadband characteristics of circularly polarized antennas using an L-shaped probe. A waveguide antenna is suitable for obtaining high gain and handling convenience in some applications; however, the asymmetrical structure of the L-shaped probe results in cross-polarization and frequency dependence on the field distribution of higher-order modes (HOM). In addition to the basic characteristics of a waveguide antenna with an L-shaped probe, the author discusses some techniques to reduce the HOM and cross-polarization. As a result, the 3-dB axial ratio (AR) is obtained with the fundamental mode even when the frequency is expanded to the region for HOM of TM. This reduction is mainly due to the cutoff structure to the TM mode around the short wall of the waveguide. Furthermore, some aperture modification techniques can reduce the cross-polarization in a wide range of angles in the radiation pattern. Such techniques and their mechanisms are discussed in this paper. The obtained performance shows that the proposed antennas have a wide range of angles of 3-dB AR in the radiation pattern, broadband characteristics in impedance and AR, and low variation in group velocity.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 춘계학술대회 논문집
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• pp.12-12
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• 2010

The hall probe measurement system was used to measure the critical current distribution of superconducting coated conductor. The system consists of reel to reel moving apparatus, 7 array hall probe, a rotary encoder and permanent magnet. The magnetic field profile across the width of superconducting coated conductor using Bean's critical state model was calculated. The effect of various parameters of the formulas on the magnetic field distribution and the effect of shape and size of artificial defects, which were formed on the surface of SmBa2Cu3O7-d(SmBCO) coated conductor using laser marking system, on the hall probe magnetic field signal of the hall probe measurement system was investigated.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 춘계학술대회 논문집
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• pp.173-176
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• 2002

In this paper, we present the combined 2-D and 3-D algorithms for automatic solder paste inspection. For automatic inspection, optical system for the combined inspection and driving unit is made. One-pass run length algorithm that has fast and efficient memory space is applied to the input image fur extracting solder paste patterns. The path of probe movement is then calculated for an automatic inspection. For a fast 3-D inspection, the phase shift algorithm based on Moire interferometry is also used. In addition, algorithms used in this paper are coded by $MMX^{TM}$. A probe system is manufactured to simultaneously inspect 2-D and 3-D for 10mm$\times$10mm field of view, with resolutions of 10 $\mu\textrm{m}$for both x, y axis and 17 $\mu\textrm{m}$for z axis, and then, experiments on several PCBs are conducted. The processing times of 2-D and 3-D, excluding an image capturing, is 0.039 sec and 0.047 sec, respectively. The credible result with $\pm$ 1$\mu\textrm{m}$uncertainty can be also achieved.

• 한국전자파학회논문지
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• 제15권7호
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• pp.635-643
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• 2004

본 논문에서는 무선 LAN 시스템에서 편파 다이버시티를 사용하기 위한 이중편파 특성을 가지는 2${\times}$2 배열 안테나를 설계, 제작하였다. 이중편파 안테나의 대역폭과 격리특성을 개선하고자 개구면 결합 급전 구조와 L형 이중 프루브 급전 구조를 사용하였다. 제작된 안테나의 -15dB 기준 반사손실 대역폭은 개구면 결합 급전에서 210MHz, L형 이중 프루브 급전에서 280MHz로 측정되었다. 두 입력포트간의 격리특성은 -40dB 이하이며, 안테나 이득은 무선 LAN 동작주파수 대역에서 14.3$\pm$0.2dBi로 측정되었다.