• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.894-897
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• 2006

The detailed studies regarding to the front and rear panel geometries and optical properties of composed layers were needed to improve the luminance and efficiency. 3-dimensional optical code can be used to analyze the variation of geometries and the changing of optical properties. The visible light distributions and illuminance results were simulated depending on the bus electrode position, ITO geometries and optical properties of dielectric layer. As the ITO area was decreased and the bus electrode was located at the outer part of cell, the illumination was increased. And we could find quantification which is related between dielectric layer and visible light distribution of PDP cell.

• Journal of Information Display
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• v.13 no.1
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• pp.51-54
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• 2012

In this study, the bias-temperature stress and current-temperature stress induced by the electrical stabilities of half-Corbino hydrogenated-amorphous-silicon (a-Si:H) thin-film transistors (TFTs) with different gate electrode geometries fabricated on the same substrate were examined. The influence of the gate pattern on the threshold voltage shift of the half-Corbino a-Si:H TFTs is discussed in this paper. The results indicate that the half-Corbino a-Si:H TFT with a patterned gate electrode has enhanced power efficiency and improved aperture ratio when compared with the half-Corbino a-Si:H TFT with an unpatterned gate electrode and the same source/drain electrode geometry.

• 한국정보디스플레이학회:학술대회논문집
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• 2000.01a
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• pp.111-112
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• 2000

The breakdown characteristics of surface discharge investigated experimentally agree well with the analytic results of previous reports [1-3] in various electrode geometries. Additionally, we find that the electrode geometry effects on the firing voltage can be understood with the ionization probability relating to the number of priming particles. We have also observed the shape of surface discharge and the surface striations in the gap geometry with the pressure, the applied voltage, and the driving frequency.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.30 no.2 s.245
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• pp.95-100
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• 2006

Electrostatic precipitators(EPs) have low pressure drop and high dust collection efficiency and are widely used for industrial dust collectors. The current-voltage characteristics, which are important to maintain high dust collection efficiency, depend on several factor: discharge electrode shape, gas flow property, dust loading etc. In this study, experiments are performed to investigate the current-voltage characteristics of the corona discharge of various electrode geometries and an empirical model is proposed to predict current-voltage characteristics of the corona discharge. The corona onset voltage correction coefficient$(\alpha)$ and the geometry correction coefficient$(k_g)$ are used to the conventional equation for wire-plate type discharge electrode. The corona onset voltages are -6.3kV and almost constant when the numbers of discharge pins are varied from 3 to 9. The length of discharge pins has very sensitive effects on the corona onset voltage. They are increased from -6.3 to -7.8kV when the discharge pin length are 8.5 and 4.5mm, respectively. The empirical model shows good agreement with experimental results and can predict the effects of discharge pin length and number.

• Journal of the Semiconductor & Display Technology
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• v.5 no.2 s.15
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• pp.7-10
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• 2006

The detailed studies regarding to the front and rear panel geometries of plasma display were needed to improve the luminance and efficiency. In plasma displays, 3-dimensional optical code can be used to analyze the variation of geometries and the changing of optical properties. The visible light distributions and illuminance were simulated depending on bus electrode position, ITO geometries, and alteration of dielectric layer's properties. This paper is concerned with development of a cell having high luminance and high efficiency for optical simulation. And the result of values could be expected to the application of real POP cell.

• Journal of Korean Tunnelling and Underground Space Association
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• v.25 no.2
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• pp.101-120
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• 2023

Electrical resistivity survey have been widely conducted at diverse scales, from a few centimeters for laboratory tests to kilometers for field tests. It measures electrical resistance through relationship of electric potential difference and current between two electrodes penetrated on the surface of medium, and eventually quantifies electrical resistivity known as inherent properties of the medium. In field or full-scale test, it assumes the electrodes as equivalent half-sphere electrodes that have a same surface area with different electrodes for ease of calculation because the contact area between electrode and medium is small and sufficient distance between two electrodes. However, small-scale laboratory test is significantly affected by the electrode geometries (penetrated depth, height, radius of electrode and distance between electrodes), which change the equipotential surface and electric current flow. Indeed, the electrode geometries may eventually cause a difference of electrical resistivity value. This study reviews the theoretical electrical resistance derived with various electrode geometries (half-sphere, cylinder, cylindrical with half-spherical tip, cylindrical with conical tip) and verifies the developed numerical module by comparing results with the theoretical electrical resistance. The distributions of electrical resistance around electrodes and among electrodes are analyzed. In addition, it is discussed how the electrical characteristic of cylindrical electrode with conical tip widely used in field test has effect on the electric current flow.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.228.2-228.2
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• 2016

The triggered vacuum switch (TVS) discharges high current through two processes. In the first process, an igniting plasma is generated at a trigger system, and the next process that a main discharge is taken place sequentially at a six-gap rod electrode within a few microsecond. In general, a triggered voltage producing the igniting plasma is increased. However, after several hundred shots, it goes down and stable, in our experiment the trigger voltage is about 5 kV after 250 shots. This triggered characteristics comes from the ceramic insulator which is covered by an electrode material, therefore we have focused on the first igniting plasma process. The igniting plasma has been generated at the surface of a ceramic insulator under a strong electric field. The electric field can be increased through modifying geometries of trigger components which compose of a trigger pin, a ceramic insulator and an enclosed holder. We fabricated not only two types of trigger pin which are a plane head and an umbrella head type, but two different holders which are a concave and a convex type. In this paper the result that the dependency of geometries for these four combined types is included, but the study of the ceramic insulator is not. The research of the ceramic insulator will be announced in the other paper.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.11
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• pp.3008-3020
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• 1994

Condensation heat transfer on a single horizontal tube with electric fields (Electro-Hydro-Dynamics, (EHD)) has been studied experimentally. Results are presented for EHD enhanced condensation of R-113 on a single horizontal tube using several electrode geometries. Especially, its attention was focused on the effects of electrode geometry, electric field strength and the gap of the electrode. In this study, single wire, helical, ring and mesh electrode were used. The range of the imposed voltage was 0~20 kV. As the voltage was increased the surface of liquid became an unstable wave, stream jet, liquid column and then liquid extraction in sequence. Among the various kinds of electrodes, the single wire electrode is suitable for practical application.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.28 no.9
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• pp.1110-1116
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• 2004

Experimental measurements of laser-induced ion mobility(LIIM) were performed for ethene/air premixed flames operated near the soot inception point. Soot was ionized using a pulsed laser operated at 532 nm. The ionization signal was collected with a tungsten electrode located in the post-flame region. ionization signals were collected using both a single electrode and dual electrode configuration. Prior LIIM studies have focused on the use of a single biased electrode to generate the electric field, with the burner head serving as the path to ground. In many practical combustion systems, a path to ground is not readily available. To apply the LIIM diagnostic to these geometries, a dual electrode geometry must be employed. The influence of electrode configuration, flame equivalence ratio, and flame height on ionization signal detection was determined. The efficacy of the LIIM diagnostic to detect soot inception in the post-flame region of a premixed flame using a dual electrode configuration was investigated. For the different dual electrode configurations tested, the dual parallel electrode geometry was observed to be most sensitive to detect the soot inception point in a premixed flame.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.16 no.4
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• pp.318-323
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• 2004

When a strong electric field is applied between a sharply curved electrode and a blunt surface, the corona may result in a gas movement in the electrode gap which is directed toward the blunt surface. That is called the corona wind. It enhances heat and mass transfer between the surface and the surrounding gas. Moreover such enhancement causes no noise or vibration, which can be applied in complex, isolated geometries, and allows simple control of surface temperatures. This paper examines the relationship between the corona wind and the relative humidity. The facility consists of high voltage power supply thin tungsten wire, plate electrode, multimeter, microammeter and flow meter. Gas velocity is a linear function of voltage, relative humidity and is proportional to the square root of the current. The maximum velocities for the positive and negative corona discharge are 1.9 m/s (2.74 CMM/m), 1.5 m/s(2.15 CMM/m), respectively.