• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.26 no.11
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• pp.62-74
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• 2012

This paper proposes a new secondary battery charger/discharger available for zero voltage discharge which is used for test equipments and formation process. The proposed system is a switching type converter, and thus the system is high efficiency and more compact as compared with linear type charger/discharger. Conventional switching type charger/discharger can not discharge secondary batteries to zero voltage because of voltage drops in the switching elements and long distributing line(typically 10m). However, the proposed system is able to discharge the battery to zero voltage in constant current mode regardless of the voltage drops. In this paper, we analyze the proposed charger/discharger and the validity of the system is verified by simulation and experiment.

• Journal of Electrical Engineering and Technology
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• v.13 no.6
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• pp.2421-2424
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• 2018

A direct measurement of an initiation carrier injection for a low voltage discharge is presented. A self-sustained pulsed discharge is utilized to characterize electrical responses of a glow discharge for varying amounts of injected initiation carriers. It is clearly demonstrated that the initiation carrier injection affects the ignition time and the breakdown voltage of the primary discharge. An abrupt reduction in the breakdown voltage for a $300{\mu}m$ gap pin-plate discharge is observed when a threshold carrier density of $3{\times}10^{11}cm^{-3}$ is injected and the breakdown voltage continues to decrease to 250 V with increasing the initiation carrier injection beyond the threshold density.

• Proceedings of the KIEE Conference
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• 2008.04b
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• pp.123-124
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• 2008

Battery is one of the emergency power. Battery reliability is a very important to keep up the minimum of building capabilities in case of interruption of electric power. Instantaneous discharge test is carried out for measuring transient voltage change(${\Delta}V$) and internal instantaneous impedance(Z), and then it is compared with discharge test results for the estimating the battery capacity. As a result, it was confirmed that the voltage change(${\Delta}V$) and the instantaneous impedance of the batteries failed in actual discharge test were higher that those of the sound batteries. Such an instantaneous discharge test can be a diagnosis of battery sound.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.8 no.3
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• pp.100-106
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• 1999

Owing to the complexity of electrical discharge machining (EDM) phenomenon, it is very difficult to determine optimal machining parameters fer improving machining performance. This paper proposes a methodology for determining optimal electrical discharge machining parameters, which is maintaining suitable current density for increasing productivity or improving surface roughness. Machining area is closely related on optimal machining parameters in electrical discharge machining process, so calculation of machining area is needed in order to determine optimal machining parameters. In this study machining area, which is corresponding to the machining position, is calculated from intersection curves between the tool surface and a horizontal plane.

• Proceedings of the KIEE Conference
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• 1999.07e
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• pp.2248-2250
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• 1999

In this paper, showering discharge type ozonizer has been designed and manufactured. The ozonizer is equipped with three electrodes(central electrode of screw shape, internal electrode and external electrode) of cylinder shape. This paper describes the following two characteristics: (1) The characteristics of discharge with variation of output voltage of AC H.V source, flux of oxygen supplied gas and discharge voltage. (2) The characteristics of ozone generation by varying flux and discharge power.

• Proceedings of the KIEE Conference
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• 1994.07b
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• pp.1649-1651
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• 1994

This paper presents a new method for estimating partial discharge position using improved cross-correlation technique and neural networks in the power transformer. When ultrasonic signal is occurred by partial discharge, we detected these signals and calculated cross-correlation values with Hamming window. Also, we estimated partial discharge position using neural network with cross-correlation values. In the result of case study, we can estimate more accurately the partial discharge position than any other algorithms.

• Proceedings of the KIEE Conference
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• 1994.11a
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• pp.267-269
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• 1994

Various types of plasma display panels(PDPs) have been developed to realize the flat panel display device. But, many of its characteristics must be improved before it can be commercialized. In order to investigate tile characteristics of micro discharge in a PDP ceil, we have constructed a micro-gap discharge system whose electrode gap can be adjustable between $100-1000{\mu}m$ within $0.1{\mu}m$ accuracy. We measured the minimum sustain voltage, current, delay time of discharge while changing parameters(electrode gap distance, electrode surface area, pressure) which influence discharge characteristics.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.503-506
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• 2004

In this paper, we suggest a new driving waveform for stable address discharge in AC PDP without the reduction of contrast ratio. To analyze the influence of cross-talk between discharge and non-discharge cells and verify that proposed waveform shows a stable address discharge, we measured the address discharge delay time. The proposed waveform shows the reduction of the cross-talk and concurrently the improvement of address voltage margin compared with those of selective reset waveform having one reset period in 1TV-Field..

• The Transactions of the Korean Institute of Electrical Engineers
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• v.34 no.9
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• pp.355-360
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• 1985

In this paper, the discharge phenomena of high frequency glow discharge in organic vapor are basically investigted to establish the growth mechanism and preparation technique for organic thin film. According to the increasing of discharge frequency, the discharge firing voltage(Vs) of organic vapor decreases. The dependence of discharge voltage(Vd) on gas pressure is generally in accord with Paschen's Law and Vd decreases as gas flow rate become larger, but increases as dischange current density become higher. And the values of Vd in organic vapor are generally higher than those of inorganic gas.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.732-735
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• 2009

In this paper, high Xe(Ne+Xe 10%, 20%, 30%) AC-PDP's discharge characteristics according to aging time were studied. The static margin, Vt close curve, discharge time lag was measured for experiments. According to increase of Xe partial pressure, the static margin and luminance was increased. As the result of analysis for misfiring probability, the misfiring is frequently occurred in accordance with increasing of aging time. To improve misfiring, we proposed 3Reset waveform and achieved misfiring probability which was improved.