• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 하계종합학술대회 논문집(5)
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• pp.77-80
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• 2000

This paper describes a new method to decide the margin for the sustain voltage of AC PDPs based on the wall-charge distribution. We model the discharge cell and measure the wall-charge when sustain pulses are applied to the AC PDP. The measured wall-charge distribution informs us of the voltage forming the maximum wall-charge which should be chosen as the sustain voltage.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 추계학술대회 논문집 Vol.15
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• pp.111-115
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• 2002

To understand the discharge characteristics in AC-PDP, it is necessary to study on the wall charge behavior. But, it is difficult to measure the wall charge directly. In this paper, the V-Q Lissajous' figure is used to measure the wall charge indirectly and analyze the wall charge behavior. With the V-Q Lissajous' figure, the discharge characteristics of AC-PDP are studied according to vary driving conditions, such as the frequency, pulse duty ratio, and rising & falling time. As a result, the V-Q Lissajous' figure is used to measure the discharge characteristics of the AC-PDP. It is confirmed that firing initial voltage and firing final voltage for discharge are effected by the aboved variables. Related with the wall voltage generation, it is thought that the difference of the slope at the V-Q Lissajous' figure is caused by charged ions inside the dielectric layer.

• 전기학회논문지
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• 제58권6호
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• pp.1151-1156
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• 2009

Unstable sustain discharges can occur at the bottom cells of the panel at high temperature. To solve this problem, the wall charge variation during an address period was investigated. A test panel of 7.5 inch XGA level was used and one green cell was measured. In order to realize operating condition equal to that of the bottom cells of 50 inch panel, the addressing stress pulses are applied. It seems that the resultant wall charge loss during address period increased with increase of stress time, temperature, pressure and Xe %. Wall charge loss increases with potential difference between scan electrode and address electrode, therefore wall charge loss can be minimized by the increase of scan voltage during address period.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.710-713
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• 2003

The wall charge is major factor to determine the discharge characteristics. The minimum sustain voltage related to the wall charge decay were investigated as a function of aging time in AC plasma display panel. For the long time scale, the wall charge decay time is dependent on the aging time. The inverse time scale of the wall charge decay has the maximum value at around 3 hours aging time and then fell down.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.756-759
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• 2003

We measure the spatiotemporal wall charge distributions on sustain and address electrodes during reset period in an ac PDP cell using the longitudinal electro-optic amplitude modulation method. We apply several reset waveforms like as ramp, exponentially growing and high voltage pulse, and compare the wall charge characteristics on address electrode as well as sustain electrodes for each reset waveforms.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2002년도 International Meeting on Information Display
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• pp.211-214
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• 2002

We present gray scale implementation method based on QMA driving technique. We clarified the mechanism of wall charge quantization through discharge current measurement. We used three wall charge states to implement gray scale. The cells would be one of fully-ON, half-On, and OFF states. We built a five sub-fields 243 level gray scale with sustain pulse count of 2, 6, 18, 54, and 162.

• 전자공학회논문지
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• 제50권3호
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• pp.174-178
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• 2013

플라즈마 디스플레이 패널에서 기입기간 동안 공통전극에서의 벽전하를 이용하여 기입방전특성을 향상시키기 위하여 수정된 구동 파형을 제시한다. 플라즈마 디스플레이의 구동방식에 있어서 초기화 기간 후에 상판의 두 전극에는 음전하가 쌓이게 되고 하판의 기입전극에는 양전하가 쌓이게 된다. 기입기간 중의 기입방전은 주사펄스와 기입펄스가 동시에 인가될 때 발생되는데 주사전극의 음전하와 기입전극의 양전하가 주로 이용된다. 반면에 공통 전극에서는 기입기간 동안 파형인가 없이 전압만 유지하기 때문에 공통전극의 벽전하는 크게 기여하지 않는다. 본 연구에서는 기입기간 중 주사 및 기입 펄스의 인가시각에 맞춰 공통 전극에서도 펄스를 인가하여 기입방전 특성을 조사하였다. 공통 전극에서의 인가전압의 높이와 펄스의 인가시각에 따른 기입 방전특성을 조사하는 실험을 각각 진행하였으며 그 결과 최적의 전압높이와 인가시각 조건하에서 기입방전의 발생시간을 종래보다 약 200 ns 정도 단축시켰다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.722-725
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• 2003

In AC plasma display, it is very important to quantify the wall voltage induced by the wall charge accumulated on the dielectric surface. If we know the quantities of the wall voltage in each period of every sequence; reset period, address period and sustain period, then it helps us to design the optimal driving waveform for high efficiency plasma display. We develop a new method to measure the wall voltage with VDS (Versatile Driving Simulator) system. From this method the wall voltage induced by a wall charge profiles just after the reset discharge of every cells in plasma display panel can be investigated and analyzed successfully. It is noted that the wall voltage profiles are influenced by the space charge and then they are stabilized as time goes by. It is also noted that both the remaining wall charge at the previous sequence and space charges contribute to wall voltage quantities just after the reset discharge. It is noted that the wall charges contribute dominantly after a few hundreds microseconds, while the space charges have been decayed within 100 ${\mu}s$ just after the reset discharge.

• Nuclear Engineering and Technology
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• 제54권6호
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• pp.2135-2146
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• 2022

A nuclear energy facility is one of the most critical facilities to be safely protected during and after operation because the physical destruction of its barriers by an external attack could release radioactivity into the environment and can cause harmful effects. The barrier walls of nuclear energy facilities should be sufficiently robust to protect essential facilities from external attack or sabotage. Physical protection system (PPS) vulnerability assessment of a typical small nuclear research reactor was carried out by simulating an external attack with a tri-nitro toluene (TNT) shaped charge and results are presented. The reinforced concrete (RC) barrier wall of the research reactor located at a distance of 50 m from a TNT-shaped charge was the target of external attack. For the purpose of the impact assessment of the RC barrier wall, a finite element method (FEM) is utilized to simulate the destruction condition. The study results showed that a hole-size of diameter 342 mm at the front side and 364 mm at the back side was created on the RC barrier wall as a result of a 143.35 kg TNT-shaped charge. This aperture would be large enough to let at least one person can pass through at a time. For the purpose of the PPS vulnerability assessment, an Estimate of Adversary Sequence Interruption (EASI) model was used, which enabled the determination of most vulnerable path to the target with a probability of interruption equal to 0.43. The study showed that the RC barrier wall is vulnerable to a TNT-shaped charge impact, which could in turn reduce the effectiveness of the PPS.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 춘계학술대회 논문집 디스플레이 광소자 분야
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• pp.159-161
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• 2000

After the square type reset pulse, the condition of remaining wall charge has been experimentally investigated in AC-PDP with VDS (Versatile Driving Simulator) system, in which arbitrary driving waveform and sequence can be used. After the self-discharge process, almost wall charges are eliminated. But some wall charges are not and its quantity is dependent on the voltage of the reset pulse. When the voltage of the reset pulse is growing, its quantity is decreased. But if the voltage of the reset pulse is above 300V, the wall voltage due to remaining wall charge is constant and its value is found out 6V. Also it is found that its polarity is always same with the one made by the reset pulse. It means that the polarity is not changed by the self-discharge.