• Journal of Science Education
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• v.46 no.2
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• pp.212-221
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• 2022

In this study, we propose an analytical model to elucidate the formation of electric fields between two parallel conducting plates. Using nine Gaussian surfaces, we investigated the charge redistributions and electric fields formed by parallel conducting plates when two charged plates get close together. The electric charges are redistributed via a new electrostatic equilibrium to create the electric field of each plates. As a result, the electric field start from + electrode plate to - electrode plate via inducing a new electrostatic equilibrium, implying that the application of Gaussian surfaces to only one of the electrodes of parallel-plate capacitors is deserved. The results will help undergraduate students understand the charge redistribution and the electric field formation in parallel-plate capacitors in a reasonable manner.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.55 no.9
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• pp.446-451
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• 2006

The output voltage value of AC high voltage source has been usually measured by employing the high voltage divider of inductive or capacitive type. In the study, we have developed a new method for measuring the output voltage up to 60kV using parallel plates electrode and electric field sensor, which are constructed by home-made. Unlikely the conventional method using a high voltage divider, this developed method makes it possible to extend the range of output voltage from known low voltage measurement to high voltage measurement. From the linearity measured between electric field and applied voltage in the output voltage range of 1kV-30kV, the output voltage value up to 60kV can be obtained by the electric field measurement using the electric field sensor. The output voltage value obtained using the method is consistent with that obtained using high voltage divider within corresponding uncertainties.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.49 no.9
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• pp.546-551
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• 2000

A micromechanical switch that can be used as a logic gate is described in this paper. This switch consists of fixed input electrodes an output electrode Vcc/GND electrodes and movable plates suspended by crab-leg flexures. for mechanical switching of an electrical signal a parallel plate actuator which comes in contact with output electrode was used. Provided that movable plates are connected to Vcc and a low input voltage(ground signal) is applied to the fixed input electrodes the movable plates are pulled by an electrostatic force between the fixed input electrodes and the movable plates. the proposed micromechanical switch was fabricated by surface micromachining technology with$2\mum$ -thick poly-Si and the measured threshold voltage for ON/OFF switching was 23.5V.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.21 no.4
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• pp.53-60
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• 2007

In this study, an experiment on the efficient construction method of plate electrodes, the influence of electric potential interference in plate electrodes, and building foundations were explored. The experimental result of the electric potential measurement was taken on the basis of the direction of movement and the condition in which the plate electrodes are laid underground in building foundations. It shows that the construction method of laying the plate electrodes vertically exhibits a more efficient reduction of electric potential in a diagonal direction and on an X axis than laying plates horizontally. For plate electrode construction in an area that has uniform conditions, the parallel joint construction method is more effective than a single construction to reduce earth electrical potential and ground resistance. In addition, a straight arrangement performs well in ground efficiency, compared to the parallel arrangement.

• 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.

• Progress in Medical Physics
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• v.9 no.1
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• pp.29-35
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• 1998

There has been necessity of an air free ionization chamber using the gold-crystal-aluminium plates, henceforth called the crystal chamber. The crystal chamber formed of parallel plates is very small in size and has more response for absorbed dose of therapeutic radiation beams. The gold plate on the crystal facing the photon and electron beam acts as an intensifier of signals and crystal plate as an ionization medium respectively. Both the copper guard ring and the aluminum collecting electrode are connected to an electrometer. Using high energy photon (6, 15 MV) and electron (9, 12, 15, 18 MeV) beams, the responses of the crystal chamber are evaluated against a PTW Farmer-type chamber at a field size of 10${\times}$10cm$^2$ and 100 cm SSD. The responses of crystal chamber for therapeutic radiation electron and photon beams are greater in magnitude by several order than Farmer. The crystal chamber has good linearity without correction factor C$\_$t,p/ with respect to the signals, a reading reproduction with good accuracy and precision less than 0.5%, and has other useful functions in measuring radiation beams.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.19 no.1
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• pp.86-93
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• 2007

The PEM (polymer electrolyte membrane) fuel cell is one of the promising fuel cell systems as a new small power generating device for automobiles and buildings. The optimal design of cooling plates installed between MEA (membrane electrode assembly) is very important to achieve high performance and reliability of the PEMFC because it is very sensitive to temperature variations. In this study, six types of cooling plate models for the PEMFC including basic serpentine and parallel shapes were designed and their cooling performances were analyzed by using three-dimensional fluid dynamics with commercial software. The model 3 designed by revising the basic serpentine model represented the best cooling performance among them in the aspect of uniformity of temperature distribution and thermal reliability, The serpentine models showed higher pressure drop than the parallel models due to a higher flow rate.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.11a
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• pp.276-279
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• 2004

Plasma enhanced chemical vapor deposition (PECVD) of silicon nitride (SiN) is a proven technique for obtaining layers that meet the needs of surface passivation and anti-reflection coating. In addition, the deposition process appears to provoke bulk passivation as well due to diffusion of atomic hydrogen. This bulk passivation is an important advantage of PECVD deposition when compared to the conventional CVD techniques. A further advantage of PECVD is that the process takes place at a relatively low temperature of 300t, keeping the total thermal budget of the cell processing to a minimum. In this work SiN deposition was performed using a horizontal PECVD reactor system consisting of a long horizontal quartz tube that was radiantly heated. Special and long rectangular graphite plates served as both the electrodes to establish the plasma and holders of the wafers. The electrode configuration was designed to provide a uniform plasma environment for each wafer and to ensure the film uniformity. These horizontally oriented graphite electrodes were stacked parallel to one another, side by side, with alternating plates serving as power and ground electrodes for the RF power supply. The plasma was formed in the space between each pair of plates. Also this paper deals with the fabrication of multicrystalline silicon solar cells with PECVD SiN layers combined with high-throughput screen printing and RTP firing. Using this sequence we were able to obtain solar cells with an efficiency of 14% for polished multi crystalline Si wafers of size 125 m square.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.2315-2320
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• 2007

This paper presents an investigative study on the efficacy of a new physical water treatment (PWT) technology using an oscillating electric field to mitigate mineral fouling in heat exchangers. Parallel graphite electrode plates immersed in water were used to generate the electric field directly in water. Artificial hard water at 500 ppm hardness was used in all fouling tests. The inlet temperatures were maintained at 23.5${\pm}$0.5$^{\circ}C$ and 85${\pm}$0.5$^{\circ}C$ for cold and hot water sides, respectively. The results at a cold water-side velocity of 0.3 m/s showed a 16-60% drop in fouling resistances from the baseline test depending on the frequency of the electric field for the PWT-treated cases.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.16 no.4
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• pp.46-54
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• 2002

A dielectric pellets bedded parallel plates with a membrane centered have been proposed as an ion separation and collection system in water. and effects of the relative dielectric constant and the applied square wave pulse voltage on the characteristics of ion separation and collection in tap water and NaCl dissolved tap water have been investigated. As a result, electrolyzed water of pH 3.1 and 10.6 were obtained with only tap water at the pulse current of 1.0[A] and flow rate of 0.5[LPM]. And the higher ionized water of pH 2.8 and pH 11.7 ware obtained in 0.1[%wt] NaCl dissolved water. When the dielectric pellets of BaTiO$_3$ having the highest dielectric constant were bedded in the ion separation and collection cell, the ionized water of pH 2.7 and pH 11.7 were obtained with only tap water. And the ionized water of pH 2.4 and pH 12.0 were obtained in 0.1[wt%] NaCl dissolved tap water with the dielectrics pellets bedded ones.