• 전자공학회논문지 IE
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• v.46 no.3
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• pp.26-32
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• 2009

The reason of the contamination in the VLSI industry is the electric charge of the wafer itself. We develop the corona discharged system of clearing static electricity with a fan. This system has automatic cleaner of discharging electrode, check the state of jot control a suitable mount of discharged ion, and monitor all state using Zigbee communication module.

• 한국전산유체공학회:학술대회논문집
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• 2010.05a
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• pp.103-108
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• 2010

This article presents computational fluid dynamics (CFD) simulations of nanoparticle movements and flow characteristics in laboratory-scale electrostatic precipitator (ESP) without corona discharge, and for simulation, it uses the commercial CFD program(CFD-ACE) including electrostatic theory and Lagrangian-based equation for nanoparticle movement. For validation of CFD results, a simple cylindrical type of ESP is simulated and numerical prediction shows fairly good agreement with the analytical solution. In particular, the present study investigates the effect of particle diameter, inlet flow rate, and applied electric potential on particle collection efficiency and compares the numerical prediction with the experimental data, showing good agreement. It is found that the particle collection efficiency decreases with increasing inlet flow rate because the particle detention time becomes shorter, whereas it decreases with the increase in nanoparticle diameter and with the decrease of applied electric voltage resulting from smaller terminal electrostatic velocity.

• Proceedings of the KIEE Conference
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• 2002.07c
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• pp.1707-1709
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• 2002

Ionic wind may be produced by DC corona discharges. In this work, the electrical effect has studied to evaluate applicability in fields of electrostatic cooling, ozone generation, electrostatic precipitation, heat transfer, air flow modification, and etc. The ionic wind velocity was measured as a function of the distance of pin to plate and the diameter of punched hole. The pin to punched-plate electrode generates airflow from pin to plate and the flow direction is controlled by the hole size of punched-plate, input voltage and distance between two electrodes. As a consequence, the ionic wind velocity is nearly proportional to the applied voltages and ranges from 1 to 3 m/sec.

• Journal of Biomedical Engineering Research
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• v.11 no.1
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• pp.131-140
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• 1990

To improve antithrombogenicity of polymer that used in vascular graft and artificial organs, seeding of human endothelial cells on the polyurethane was studied. Human endothelial cells were ismlated from human umbilical veins, using type I collagenase, and identified with goat anti vWF antibodies. Human endothilial cell seeding was tried upon the polyurethane which has good mechanical property and resists stresses. The hydrophobic polyurethane surface was changed hydrophilic by corona discharf:e treatment. Surface hydrophilicity was measured with Wilhemly plate method and the goniometer. To evaluate matrix protein adsorption, fibronectin adsorption test was done. To eveluate cell adhesion, human endothelial cell attachment forces were measured rising a perfusion chamber of , ism diamter. Less cells were detached from the hydrophilically treated polyurethane. This showed that corona discharge on the polyurethane could improve matrix adsorption and endothelial cell attachment.

• Environmental Engineering Research
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• v.11 no.3
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• pp.164-171
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• 2006

Numerical modeling of the flow velocity fields for the near corona wire electrohydrodynamic (EHD) flow was conducted. The steady, two-dimensional momentum equations have been computed for a wire-plate type electrostatic precipitator (ESP). The equations were solved in the conservative finite-difference form on a fine uniform rectilinear grid of sufficient resolution to accurately capture the momentum boundary layers. The numerical procedure for the differential equations was used by SIMPLEST algorithm. The Phoenics (Version 3.5.1) CFD code, coupled with Poisson's electric field, ion transport equations and the momentum equation with electric body force were used for the numerical simulation and the Chen-Kim ${\kappa}-{\varepsilon}$ turbulent model numerical results that an EHD secondary flow was clearly visible in the downstream regions of the corona wire despite the low Reynolds number for the electrode ($Re_{cw}=12.4$). Secondary flow vortices caused by the EHD increases with increasing discharge current or EHD number, hence pressure drop of ESP increases.

• Bulletin of the Korean Chemical Society
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• v.31 no.10
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• pp.2783-2785
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• 2010

Searching for new molecular radicals which are believed to play an important role as reaction intermediates in aromatic chain reactions, we have applied the technique of corona excited supersonic expansion employing a pinhole-type glass nozzle to obtain the vibronic spectrum from the corona discharge of precursor 3,5-difluorotoluene with a large amount of inert carrier gas helium. An analysis of the observed spectrum revealed that many vibronic bands are from other isomeric difluorobenzyl radicals generated in the jet by migration of the fluorine atom or methylene group to the adjacent position in the 3,5-difluorobenzyl radical. A possible mechanism was proposed for the formation of other isomers by using a bridged cyclic intermediate structure.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.45 no.3
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• pp.451-455
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• 1996

This paper specified the measurement results conducted by the Korea Electric Power Research Institute (KEPRI) 765kV double circuit transmission test line that measured the audible noise, hum noise, radio interference, electric field and aeolian measurement. This test line consists of 6-480mm$^{2}$ conductors per phase. The analysis of the test results shows that this 6-Rail conductor bundle satisfies the audible noise criterion under the stable rainy weather condition and the radio interference level under the fair weather. And the other items are also agreed with the design level criterion. (author). 9 refs., 7 figs., 2 tabs.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.173-176
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• 2000

In this paper, we investigated the surface degradation of HTV silicone rubber used for a polymeric insulator by UV irradiation. To study the surface ageing properties by W irradiation, we used the corona discharge charging and contact angle. Therefore, we observed the change of surface charge retention and decrease of surface hydrophobicity. Also, we discussed the chemical change in the surface range using the analytic equipment such as SEM, ATR-FTIR, ESCA. Therefore, it is found that the scissor of characteristic bonding and the reattachment of oxidant bonding was developed by UV rays radiation. As discussing the corona ischarge charging and the change of contact angle, it is found the effect of UV irradiation and the mechanism of chemical reaction

• Journal of the Korean Society of Safety
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• v.10 no.2
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• pp.72-76
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• 1995

An electrostatic passive neutralizer without HV power source has been used widely to reduce charges on insulators such as running plastic films, papers and cloths, but its elimination characteristics and safely have been hardly investigated in detail. Especially, an operation of the passive neutralizer depends primarily on the charged insulator and the elimination ability does not depend on only the neutralizer, because an electrostatic elimination is caused by corona discharges occurring between the passive neutralizer and charged insulator. From a reason described above, the purpose of this study is to examine experimentally the elimination ability of the passive neutralizer. Experiments were made on the corona discharges between the passive neutralizer and charged insulator running at high velocity in practical field to make clear the setting condition of the passive neutralizer for operating effectively and safely. Results obtained from field experiments are presented in this paper.

• Proceedings of the KIEE Conference
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• 2006.07c
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• pp.1469-1471
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• 2006

It is very important to discriminate noises such as air corona in measuring on-site partial discharges (PD). Therefore, in order to investigate the possibility of separating PD(partial discharge) and noises through the pulse analysis, pulse shapes measured by a resistive sensor and a HFCT were analyzed and PA(pulse analysis) were performed. For the purpose, the HFPD detection and PA system has been developed. Also void discharges and air corona were adopted as the artificial defect and noises, respectively.