• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.790_791
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• 2009

본 논문에서는 전자기 유한요소 해석을 통하여 원전 증기 발생기(SG, Steam Generator) 세관의 결함 변화에 따른 배열와전류프로브의 와전류탐상 특성을 해석하였다. 프로브의 전자기적 특성을 위해 맥스웰 방정식을 이용하여 지배방정식을 유도하였고, 이를 3차원 전자기 유한요소법을 이용하여 문제를 해석하였다. 해석을 위한 선정한 결함은 프로브의 특성파악을 위한 표준시험편과 원전 SG세관에 발생 가능한 결함인 Pitting, SCC, Wear, Multi SCC 결함을 선정하였다. 해석 대상으로는 원자력발전소 증기발생기 세관으로 사용되고 있는 Inconel 600 도체관을 사용하였다. 본 논문으로 통하여 결함의 형상, 크기, 시험주파수의 변화에 따른 탐상신호의 변화를 확인할 수 있었다. 본 논문의 결과는 배열와전류프로브의 와전류탐상 신호 평가시 도움이 될 것이다.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.407.3-408
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• 2002

A portable near infrared (NIR) system which was newly integrated by our lab has been used to develop a non-invasive blood glucose monitoring. The portable NIR system includes a tungsten halogen lamp, a photo diode array type-InGaAs detector, and specialized reflectance fiber optic probes. The shape of probes is composed of two parts. one for illumination into sample and the other for receiving the radiation from sample. Three kinds of probes with different distance between illumination and receiving part. such as 0.03. 0.1. and 0.5mm, were investigated for optimization. (omitted)

• Journal of KSNVE
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• v.8 no.4
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• pp.603-608
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• 1998

In order to obtain basic data for the prediction of railway noise propagation, the noise radiation characteristics (source position, radiation directivity, etc) of trains were measured by using the sound intensity method. The measurements were performed at a side of railway by setting an intensity-probe array. As the measurement results, it was found that rolling noise due to interaction between wheel and rail and motor noise radiation from the lower part of train are dominant. The location of main sound sources can be described as being at the height of 0.1m in the center line of track, and the radiation directivity in the cross section of actually running trains are presented as a dipole source.

• 한국초전도학회:학술대회논문집
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• v.10
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• pp.103-106
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• 2000

We have studied the magnetic properties in Bi$_2$Sr$_2$CaCu$_2$O$_8$ single crystal with columnar defects using micro Hall-probe array. We found that fold profiles inside sample were similar to the Bean's critical state model from the magnetic hysteresis measurement. In the magnetic relaxation measurement, the normalized relaxation rates were maximum near the center and decreased toward the edge of the sample expect zero gauss. The relaxation rates as a function of the temperature were maximum near the 40K and rapidly decreased both sides of the peak.

• Journal of the Korean Society of Safety
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• v.10 no.4
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• pp.9-12
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• 1995

Detection of small defects by medical ultrasonic testing when the thermal sprayed coating by $MoSi_2$ on the metal is done. The defects may occur at the bonded surface. So, the detecting method of the defects by non-destructive in spection is desired. Here, in order to examine the possibility of the detection of the small defects by the ultrasonic. The electronic scanning ultrasonic equipment using an array probe developed as the medical ultrasonic diagnostic equipment is applied for the detection of the metal material defects. It's validity is investigated.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2008.05a
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• pp.431-433
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• 2008

본 논문에서는 원자력 발전소의 SG세관 검사를 위한 배열와전류프로브의 와전류탐상 특성을 해석하였다. 신호해석을 위해 원자력발전소 SG 세관의 내부 및 외부결함을 모델링하였으며, 결함의 깊이는 세관 두께의 40[%]로 하였다. 해석방법은 3차원 유한요소법을 이용하여 전자기 수치 해석을 수행하였다. 두 종류 결함의 수치해석 비교 결과 내부결함의 신호가 외부결함 신호에 비해 크게 발생되는 것을 확인할 수 있었으며, 또한 획득한 신호를 ASME 표준 시험편을 이용한 배열와전류 프로브의 와전류탐상 실험신호와 비교하였다. 본 논문의 결과는 원전설비검사를 위한 배열와전류프로브 신호의 특성해석에 도움이 될 것으로 사료된다.

• Proceedings of the KOSOMBE Conference
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• v.1997 no.11
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• pp.31-34
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• 1997

A semiconductor microelectrode array has been successfully used in obtaining single unit recordings from medial giant nerve of clay fish, rat saphenous nerve and abdominal ganglia of aplysia. The recording device fabricated using silicon microfabrication techniques is a depth-probe type and, previously, has been mostly used to record from central nerve system of vertebrates. From invertebrates, and also from peripheral nerves of vertebrates, however, the quality of the recorded signal depends heavily on the recording conditions, such as the proximity of the electrode site to the nerve cells and the size of the neuron. We have modeled the signal to noise ratio as unctions of these parameters and compared the experimental data with the calculated values thus obtained.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.05a
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• pp.65-70
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• 2006

In this study, a DNA chip with a microelectrode array was fabricated using microfabrication technology. Several probe DNAs consisting of mercaptohexyl moiety at their 5 end were immobilized on the gold electrodes by DNA arrayer. Then target DNAs were hybridized and reacted with Hoechst 33258, which is a DNA minor groove binder and electrochemically active dye. Linear sweep voltammetry or cyclic voltammetry showed a difference between target DNA and control DNA in the anodic peak current values. It was derived from Hoechst 33258 concentrated at the electrode surface through association with formed hybrid. It suggested that this DNA chip could recognize the sequence specific genes.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.1
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• pp.37-45
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• 2000

Though microstrip antenna has several advantages, it makes engineers struggle against the difficulties of narrow bandwidth and scan-blindness with probe-feeding and array configuration. To overcome these disadvantages, stacked patch and cavity-backed structure had been proposed. But this structure can not be analyzed easily because we have no concrete means to analyze it. So the algorithm to analyze the structure should be established to make it useful. This paper explained the algorithm of moment method to analyze the structure and verified it by comparing the calculated and measured results.

• Proceedings of the KSR Conference
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• 2003.10c
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• pp.275-280
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• 2003

The Korean high speed train is designed to run at very high speed such as 350km/h. At this time, ballast in roadbed is dispersed by high speed air flow and this hits the substructure of the train. It becomes the factor of damaging the train. To investigate the main factor and possibility of ballast dispersion, the substructure flow is measured by Kiel-Probe Array System at G7 train experiment. And the wind tunnel experiment is performed with ballast in our research. Also CFD analysis is performed by assuming that the flow field is 2D and using simple shaped cross-tie and flat substructure of the train. By comparing the experimental results and CFD analysis, the accuracy of the analysis is checked. They will become the basic research data for the analysis and optimization of train substructure to prevent the ballast dispersion.