• Proceedings of the KIEE Conference
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• 2003.07c
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• pp.1719-1721
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• 2003

In this paper, electrical characteristics of inductively coupled plasma in an electrodeless fluorescent lamp were investigated using a Langmuir probe with a variation of Ar gas pressure. The RF output was applied in the range of 5-50W at 13.56MHz. The internal plasma voltage of the chamber and the probe current were measured while varying the supply voltage to the Langmuir probe in the range of -100V ${\sim}$ +100V. When the pressure of Ar gas was increased, electric current was decreased. There was a significant electric current increase when the applied RF power was increased from 10 W to 30 W. This implies that this method can be used to find an optimal RF power for efficient light illumination in an electrodeless fluorescent lamp.

• Journal of the Korean institute of surface engineering
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• v.44 no.1
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• pp.26-31
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• 2011

Numerical modeling is used to investigate the perturbation of a single Langmuir probe (0.2 mm diameter shielded with 6 mm insulator) inserted along the center axis of a cylindrical inductively coupled plasma chamber filled with Ar at 10 mTorr and driven by 13 MHz. The probe was driven by a sine wave. When the probe tip is close to a substrate by 24.5 mm, the probe characteristics was unperturbed. At 10 mm above the substrate, the time averaged electric potential distribution around the tip was severly distorted making a normal probe analysis impossible.

• Food Science of Animal Resources
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• v.23 no.1
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• pp.28-31
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• 2003

The incidence of PSE pork by lairage time, use of electric probe, stunning voltage condition and carcass chilling rate was compared. The incidence of PSE pork was 22.2% when pigs were held in lairage overnight without electric probe, whereas it was 59.3% when held in lairage for < 1.5 hr with electric probe before slaughter. The incidence of PSE pork was 42.37% when pigs were treated with 230 V of stunning condition, and was 66.67% when treated with 500V of stunning condition. The incidence of PSE pork was 52.2% when the ultimate carcass internal temperature was controlled higher than 38$^{\circ}C$ with the slow chilling(-5$^{\circ}C$ for 70 min), and was 39.6% when controlled lower than 30$^{\circ}C$ with the fast chilling(-15$^{\circ}C$ for 70 min). Results indicated that the incidence of PSE pork was decreased by 37.1% with lairage overnight and without use of electric probe, 24.3% with low voltage stunning treatment and 12.6% with fast chilling. However, the incidence of PSE pork was not significantly correlated with carcass weight.

• Proceedings of the KIEE Conference
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• 2002.07c
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• pp.1846-1849
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• 2002

A shorted-turn test was performed at the Sininchon combined cycle power plant on gas turbine generators. The test was conducted using a permanent flux probe and on-line diagnosis system. The flux probe installed in the generator air gap senses the field winding slot leakage flux and produces a voltage proportional to the rate of change of the flux. This pattern of flux variation is a signature unique to each field winding. We have also applied a voltage waveform analysis technique that can identify the pole location, slot number and number of shorted-turn with each slot.

• Proceedings of the KIEE Conference
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• 1998.07e
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• pp.1721-1724
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• 1998

A shorted-turn test was performed at the Pyungtaek combined cycle power plant on gas. turbine generator #4. The test was conducted using a permanent flux probe and digital oscilloscope. The flux probe installed in the generator air gap, senses the field winding slot leakage flux and produces a voltage proportional to the rate of change of the flux. This pattern of flux variation is a signature unique to each field winding. We have also applied a waveform analysis technique that can identify the pole location, slot number, and number of shorted-Turns with each slot.

• Proceedings of the KIEE Conference
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• summer
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• pp.899-901
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• 2004

This paper analyzes recording density according to the shape variation of Electric Probe writer, and present a shape design method for improving recording density in perpendicular electric recording device. The gradient of electric field has to be steep to improve recording density because transition region on the media becomes wider when recording. The optimum shape of electrode could be archived by using Response Surface Methodology and 2-Dimensional Finite Element Method.

• Proceedings of the KIEE Conference
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• 2003.07c
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• pp.1747-1749
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• 2003

발전기 회전자 권선에 종종 발생하는 층간단락 현상을 찾아내는 진단기법에는 크게 두가지가 있으며, 정지중 진단기법인 분담전압 시험과 운전중 진단기법인 flux probe 시험이다. 본 논문에서는 서인천복합화력발전소 #2 스팀터빈 발전기에 대하여 분담전압 및 flux probe 시험을 시행하여 회전자 권선의 건전성을 확인하고, 그 결과를 상호 비교, 분석하여 정지중 및 운전중 진단기법의 신뢰성을 평가하였다.

• Proceedings of the Korean Nuclear Society Conference
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• 2005.10a
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• pp.957-958
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• 2005

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2007.11a
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• pp.195-196
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• 2007

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.05e
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• pp.89-91
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• 2003

In this paper, using a Langmuir probe Ar gas characteristic of electrodeless fluorescent lamp which used an inductively coupled plasma were investigated. The RF output changed into 5-50W in 13.56MHz. At this time internal plasma voltage of the chamber and probe current were measured while changing in -70V - +70V with a supply voltage by Langmuir probe. If pressure of Ar gas was increased, the electric current tended to decrease. Also, an electric current was increased according to an increase of a RF output.