• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.3
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• pp.604-608
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• 2010

An electric fan for cooling high density electronic devices is limited and operated in very low efficiency. The corona discharge is utilized as the driving mechanism for an ionic gas pump, which allows for air flow control and generation with low noise and no moving parts. These ideal characteristics of ionic pump give rise to variety applications. However, all of these applications would benefit from maximizing the flow velocities and yields of the ionic pump. In this study, a needle-mesh type ionic pump has been investigated by focusing on the radius of curvature of corona needle points elevating the ionic wind velocity and efficiency. It is found that the radius of curvature of the corona discharge needle point influences significantly to produce the ionic wind and efficiency. As a result, an elevated ionic wind velocity and increased ionic wind generation yield can be obtained by optimized the radius of curvature of the corona needle electrode.

• Journal of the Korea Institute of Military Science and Technology
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• v.5 no.3
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• pp.105-112
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• 2002

A combined process of non-thermal plasma and catalytic techniques has been investigated to treat toxic gas compounds in air. The treated gas in the present study is $CH_3$CN that has been known to be a simulant of toxic chemical agent. A planar type dielectric barrier discharge(DBD) reactor has been used to generate non-thermal plasma that produces various chemically active species, O, N, OH, $O_3$, ion, electrons, etc. Several different types of adsorbents and catalysts, which are MS 5A, MS 13X, Pt/alumina, are packed into the plasma reactor, and have been tested to save power consumption and to treat by-products. Various aspects of the present techniques, which are decomposition efficiencies along with the power consumption, by-product analysis, reaction pathways modified by the adsorbents and catalysts, have been discussed in the present study.

• Proceedings of the KIEE Conference
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• 2003.10a
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• pp.220-222
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• 2003

In this paper, we analyze on the discharge characteristics through 1-D simulations in an at plasma display panel discharge cell. The model is based on a Poisson' equation, continuity and drift-diffusion equation. Results are presented in a 95% neon, 5% xenon gas mixture, for a gap length of 100us and a gas pressure of 400Torr at ambient temperature. Results for other gap length are also discussed. As a result, an increase of the gap cause increase of luminous efficiency but with larger sustaining voltage.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.8
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• pp.1423-1428
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• 2010

The results of off-line and on-line diagnostic tests performed on the stator winding of an air-cooled gas turbine(G/T) generator are reported in this paper. Off-line diagnostic tests included measurements of the ac current, dissipation factor(tan${\delta}$), and partial discharge(PD). Six epoxy-mica capacitors were installed in the three phases of G/T generator for performing on-line diagnostic testing with the turbine generator analyzer(TGA). The TGA showed that the normalized quantity number(NQN) and the PD magnitude($Q_m$) were high in phase A of the stator winding. Internal discharges were generated in phases B and C, and slot discharge occurred in phase A. According to the trend analyses of the NQN and $Q_m$ values available for insulation condition assessment for G/T generator stator windings, it was concluded that phases B and C were in good condition, whereas phase A has been significantly deteriorated.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.53 no.3
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• pp.133-136
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• 2004

Low-Pressure inductively coupled RF discharge sources have important industrial applications mainly because they can provide a high-density electrodeless plasma source with low ion energy and low power loss. In an inductive discharge, the RF power is coupled to the plasma by an electromagnetic interaction with the current flowing in a coil. In this paper, the experiments have been focussed on the electric characteristic and carried out using a single Langmuir probe. The internal electric characteristics of inductively coupled Ar RF discharge at 13.56(MHz) have been measured over a wide range of power at gas pressure ranging from 1∼70(mTorr).

• Proceedings of the KIEE Conference
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• 2001.07c
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• pp.1682-1684
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• 2001

In removing the flue-gas using electrical discharge method, it is important to dissociate or ionize the atoms and molecules by the collisions with energetic electrons and it produces the radicals that are used to decompose the pollutants. For that purpose, a bidirectional pulsed voltage is used to produce lots of energetic electrons efficiently and increase the power efficiency. The simulation is performed with changing the pulsewidth under the fixed applied voltage. The particle-mesh model coupling the NGP(nearest-grid-point) to FEM(finite element method) is used to simulate the behavior of electrons and the spatio-temporal variation of the electric field for the streamer in discharge tube.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07b
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• pp.1115-1118
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• 2003

A great part of flint fuel is Hydrogen and carbon's combination. they should be generated steam and carbon gas when combine with oxygen for perfect combustion in the inside of engine, but the pollutive material especially NOx and Soot are exhausted, even though fuel is combine perfectly. In this paper the characteristics of exhaust material from diesel engine is investigated for the corona discharge-EGR hybrid plasma reactor, which combined corona discharge with EGR system. NOx is decreased in all load and applied voltage to plasma reactor. However Soot is increased as increasing EGR rate and it is decreased as increasing applied voltage.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.120-120
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• 2010

To detect the PD events, we have studied a fusion sensor, the UHF sensor and the single-walled carbon nanotube(SWNT) gas sensor. We are accustomed to the UHF sensor which have employed to detect the partial discharges in apparatus GIS-like. But the SWNT gas sense is a newly way proposed to detect the partial discharges. In this study, we monitored not only the changes of the electrical conductance of the SWNT sensors in responding to the PD events but also the signal of the UHF sensor at the same time with IEC 60270 standard method for reference on the partial discharge events.

• Food Science and Biotechnology
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• v.15 no.6
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• pp.959-966
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• 2006

The electron-capture detector (ECD) of gas chromatographs (GC) has been used widely in pesticide analysis. However, as ECD relies on radioactive material, it is troublesome to purchase and maintain. Therefore, potent replacements for ECD were investigated. A Pulsed-discharge detector (PDD) for ECD was tested and the analytical results of PDD (ECD mode), ${\mu}ECD$, and nitrogen-phosphorus detector (NPD) were compared for 107 pesticides including organochroline, organophosphorus, pyrethroids etc. The number of pesticides identified at the lowest limit of detection (LOD) was 36, 29, and 2 for PDD, ${\mu}ECD$, and NPD, respectively. The remaining pesticides showed same response to PDD and ${\mu}ECD$. The GC-PDD analysis of pesticides spiked into representative agricultural products (brown rice, spinach, and mandarin oranges) also showed good and/or equivalent recoveries using $GC-{\mu}ECD$.

• Proceedings of the KIEE Conference
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• 1997.11a
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• pp.379-381
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• 1997

The dielectric layers in AC plasma display panel(AC PDP) are essential to the discharge cell structure, because they protect metal electrodes from sputtering by positive ion and from a sheath of wall charges which are essential to memory function of AC PDP. Furthermore, this layer should be transparent because the visible light must pass through the layer. In this paper, the dielectric breakdown strength and transparency of the dielectric layer on the discharge electrodes are studied. The variables in this test are the dielectric layer thickness, dielectric firing condition, gas pressure, species of gas and so on.