• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 1999.11a
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• pp.53-57
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• 1999

To investigate the discharge dynamics of alternating current plasma display panel (ACPDP), we measured the spatio-temporally resolved VUV and IR emission by an intensified charge coupled device (CCD). The breakdown beings around the anode inner edge and moves towards the cathode surface. As the ionization intensifies in front of the cathode surface, another emission region appears on the anode surface. While the anode side emission does not move but grows, the cathode side emission moves out and spreads over the entire cathode surface. The discharge dynamics emission by a 2 dimensional numerical simulation suggests that a cathode-directed streamer formation play an important role.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2005.06a
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• pp.757-763
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• 2005

A multi-channel seismic system has been developed and applied for bedrock mapping in near shore environment. The system is composed of an analog signal processor and an A/D converter installed on the computer, and a streamer with the group interval of 5 meters. The system is accomplished with a data acquisition program which controls the system and a data processing software. With the PC-based shallow marine seismic survey system high-resolution 2-D marine seismic profiles which have high S/N ratios can be obtained after appropriate data processing.

• Applied Science and Convergence Technology
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• v.27 no.2
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• pp.23-25
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• 2018

With respect to the electrode structure and the discharge characteristics, the atmospheric pressure plasma sheet of a thin polyimide film is introduced in this study; here, the flexible plasma device of a dielectric-barrier discharge with the ground electrode and the high-voltage electrode formulated on each surface of a polyimide film whose thickness is approximately $100{\mu}m$, that is operated with a sinusoidal voltage at a frequency of 25 kHz and a low voltage from 1 kV to 2 kV is used. The streamer discharge is appeared along the cross-sectional boundary line between two electrodes at the ignition stage, and the plasma is diffused on the dielectric-layer surface over the high-voltage electrode. In the development of a plasma sheet with thin dielectric films, the avoidance of the insulation breakdown and the reduction of the leakage current have a direct influence on the low-voltage operation.

• Electrical & Electronic Materials
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• v.10 no.8
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• pp.807-811
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• 1997

In this paper we have investigated the removal characteristics of NOx by pulsed corona discharge with a multi-pointplane electrode where a magnetic field is applied in the discharge region. The efficiency of NOx removal was measured and analyzed as a function of pulse frequency gas flow rate NOx initial concentration magnetic flux density. In this result the highest removal efficiency of NOx was obtained at the following operating conditions; the frequency =400[Hz] gas flow =1[$\ell$/min] initial concentration= 400[ppm] and magnetic flux density=0.36[T].

• Electrical & Electronic Materials
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• v.9 no.4
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• pp.385-395
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• 1996

이 논문은 금속성 돌기물에 의한 불평등전계중에서의 비진동성과 진동성 임펄스전압에 의한 SF$_{6}$ 가스의 절연파괴 특성에 대해 기술하였다. 절연파괴전압-시간특성을 가스압 0.1-0.5MPa의 범위에서 정.부 극성의 전압을 인가하여 측정하였으며, 그리고 50.ohm.분류기를 통해서 전구방전 전류를 관측하였다. 가스압력에 의한 리이더 진전시간의 의존성도 측정하였다. 스트리머 코로나에 의해 발생하는 공간전하에 의한 국부전계강화는 시험갭의 전기적 절연파괴에 영향을 미치는 것으로 판명되었다. 절연파괴는 초기 스트리머 코로나로부터 발단되어, 국부전계강화에 의한 리이더진전으로 이루어진다.

• Proceedings of the KIEE Conference
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• 1998.07e
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• pp.1812-1814
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• 1998

Recently plasmas have been used to reduce the undesirable gases $SO_2$, NO, and $NO_2$. Especially bidirectional pulsed voltages were used to increase the efficiency of flue-gas reactors. The particle-Mesh model using NGP (Nearest-grid-point) and FEM (Finite Element Method) calculate the detailed space-time variations of the electric fields for the streamer and it makes the characteristics of reactor more clearly. In this simulation NO is considered a dominant gas.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.7
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• pp.1276-1281
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• 2010

To analyze the gas discharge phenomena in parallel-plane electrodes, the fully coupled finite element method (FEM) considering secondary electron emission effects in discharge column was adopted in this paper. Two coupled equations of the hydrodynamic diffusion-drift equations for three carriers and the Poisson's equation for electric scalar potential should be solved as a system equation. The proposed method including two secondary electron processes of the photoemission and background ionization has been successfully applied to evaluating the breakdown voltage in parallel-plane electrodes and is verified by comparing its numerical results with the experimental ones. From the obtained results, it is inferred that the proposed numerical scheme will be useful for predicting and understanding streamer transient phenomena.

• 전기의세계
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• v.29 no.6
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• pp.344-348
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• 1980

$SF_{6}$가스의 절연파괴특성 및 화학적특성에 관한 것을 종합해보면, 첫째, $SF_{6}$의 방전은 1개의 전자 avalanche중의 전자수가 임계치 Norit가 $10^{8}$정도에서 streamer에의 전이가 일어나므로서 이루어지며, 둘째, $SF_{6}$의 (.alpha.-.eta.)/.rho.와 E/.rho.의 관계는 .alpha.=.eta.근방에서 직선으로 상승되어 절연파괴에 극히 중요한 뜻을 가지며, 셋째, 두번째의 .alpha.=.eta.에 있어서의 구배는 보통의 기체보다 수 10배크기 때문에 최대전계를 부여하는 전극근방만이 공극의 방전개시를 지배하며, 넷째, 전기기구에 있어서 $SF_{6}$가스의 화학적변화의 energy원으로서는 arc, corona, 열을 들 수 있으며 특히 $SF_{6}$가스중과 공기중과의 내 Corona성을 구하기 위한 인가전압일내 Corona수명시간은 $SF_{6}$가스중이 공기중보다 길다는 것이다.

• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.2002-2004
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• 2000

The discharge processes in electro-negative gases with non-uniform field gape are composed of the formation of pulsed streamer corona, the transition of the streamers into leader step, the temporal development of the leader channel, and the stepped propagation of leader through the gap. In this paper, the first corona inception characteristics in $SF_6$ gas and $SF_{6}-N_{2}$ mixtures, related to the propagation of loader and the space charge effect, were experimentally investigated with positive and negative transient impulse voltages.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2005.11a
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• pp.271-273
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• 2005

In order to carnation productivity improvement, ozonizer and negative ionizer has been designed and manufactured. The ozone is generated by DC positive streamer discharge and the negative ion is generated by DC negative discharge. When the ozone and negative ion are supplied growth room and farm to carnation cultivation, the carnation productivity is improved.