• Proceedings of the KIEE Conference
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• 2000.07e
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• pp.29-32
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• 2000

Ozone has been widely applied to many industrial fields because of its strong oxidation effects. Therefore, the studies have been progressed for the effective and high concentration of one generation. The silent or surface discharge have been mainly used for high concentration ozone generation until now. But these two types of ozone generators have shortcomings to be improved. In this study, the ozone generator which improved the shortcomings of above two type of ozone generators was proposed and manufactured for high concentration ozone generation. And the proposed ozone generator could generate the surface and barrier discharge simultaneously. For this purpose, a mesh type discharge electrodes were proposed and the experiments were fulfilled as a function of the widths and spacings of mesh electrodes and gap spacings between the dielectric barrier and mesh electrode. When the width of mesh electrode[WM] and spacing of mesh electrode[SM] are 0.3[mm] and 0.8[mm] respectively, the maximum ozone concentration of 2.96[vol%] was obtained at 5.6[kV], 830[mA], gap spacing (S)=0.65[mm].

• Food Science and Biotechnology
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• v.18 no.1
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• pp.89-94
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• 2009

Frequent outbreaks of foodborne illness have been increasing the awareness of food safety. Conventional methods for pathogen detection and identification are labor-intensive and take days to complete. Some immunological, rapid assays are developed, but these assays still require prolonged enrichment steps. Recently developed biosensors have shown potential for the rapid detection of foodborne pathogens. In this study, an impedimetric biosensor was developed for rapid detection of Salmonella entritidis in food sample. To develop the biosensor, an interdigitated microelectrode (IME) was fabricated by using a semiconductor fabrication process. Anti-Salmonella antibodies were immobilized based on neutravidin-biotin binding on the surface of the IME to form an active sensing layer. To evaluate the effect of electrode gap on sensitivity of the sensor, 3 types of sensors with different electrode gap sizes (2, 5, and $10{\mu}m$) were fabricated and tested. The impedimetric biosensor could detect $10^3\;CFU/mL$ of Salmonella in pork meat extract with an incubation time of 5 min. This method may provide a simple, rapid, and sensitive method to detect foodborne pathogens.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.49 no.12
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• pp.679-684
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• 2000

Closing switch, key component of pulsed power system, is constructed simply and used frequently due to the easy control and manufacture of one. The kind of one are spark-gap, triggered vacuum switch, pseudo-spark switch and INPIStron. But the electrode of spark gap switch is damaged with the hot spot by Z-pinch and then the life of one become short. INPIStron with inverse pinch effect has long life but it is difficult trigger system to provide uniform discharge between cathode and anode. In this paper, the design and manufacturing of INPIStron with gas puffing trigger method in order to supply uniform discharge inter-electrode and the performance of the developed INPIStron applied to 500[kA]-2[MJ] pulsed power system is presented.

• Proceedings of the KIEE Conference
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• 1995.07c
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• pp.1413-1416
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• 1995

Plasma Display(PDP) was successfully demonstrated on 30-60inch display panel. Research for mass production is also been accelerating. The basic study of PDP are mainly focused on understanding of micro discharge in each cell In this paper, DC PDP with Ag electrode is made and the discharge charcateristics in micro gap is studied with the variation of the distance of electrode gap and the pressure in discharge cell.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.12 no.2
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• pp.17-22
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• 2003

Electropolishing is the electrolytic removal of metal in a highly ionic solution by means of an electrical potential and current. It is normally used to remove a very thin layer of material on the surface of a metal part or component. Electropolishing is able to enhance the material properties of a workpiece and to change its physical dimensions. Also, It is suitable for the polishing of both complex shapes and hardened materials, which are difficult to machine mechanically. therefore, the aim of the present study is to investigate the characteristic of Electropolishing A12024 in terms of current density, polishing time and electrode gap, etc.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.4
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• pp.773-776
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• 2007

A microstructure array has been proposed for micro plasma generation using electroplating and double exposed process. A stable atmospheric plasma has been generated at a low voltage by utilizing the micro electrode gap. Self-aligned microstructure can provide uniform electrode overlap with precisely controlled gap between the electrodes. The proposed structure allows for triode operation, which can expand the generated plasma over a large area by applying a lateral electric field. Electrical characteristics of the micro triode confirm the large numbers of the plasma ions are drifted to the secondary cathode by the lateral electrical field.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.10a
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• pp.943-946
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• 1997

Electropolishing is the controlled electrochemical removal of surface metal, resultmg in a brilliant appearance andimproved properties. Sometimes described as "reverse plating," the process has a leveling effect, which produces smoothnessand increased reflectivity. Unlike conventional mechanical finishing systems, the electropolishing does not smear, bend,stress or fracture the crystalline metal surface to achieve smoothness. Instead, electropolishing removes metal from thesurface producing a unidirectional pattern that is stress-free, microscopically smooth and often highly reflective. In addition,improved corrosion resistance and passivity are achieved on many ferrous and some non-ferrous alloys. Pure aluminium doesnot electropolish well, if at all, but most other alloys of aluminum electropolish excellently.Therefore, the aim of this study is to determine the characteristics of electropolishing aluminium alloy in term of currentdensity, machining time, temperature, electrode gap and workpiece surface measurementkpiece surface measurement

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1998.10a
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• pp.186-191
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• 1998

Electropolishing is the anodic dissolution process in the transpassive state. It removes non-metallic inclusions and improves mechanical and corrosion resistance of stainless steel. If there is a Bailby layer, it will be recovered again. Electropolishing is normally used to remove a very thin layer of material on the surface of a metal component. The aim of this study is to determine the tendencies of electropolishing STS316L tubes in terms of current density, machining time, temperature, electrode gap and surface roughness.

• Transactions of the Korean Society of Automotive Engineers
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• v.3 no.6
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• pp.69-77
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• 1995

This paper presents performance investigation of a continuously variable ER(Electro-Rheological) damper for passenger vehicles. A dynamic model of the damper is formulated by incorporating electric field-dependent Bingham properties of the ER fluid. The Bingham properties are experimentally obtained through Couette type electroviscous measurement with respect to two different particle concentrations. The governing equation of the hydraulic model treating three components of fluid resistances;electrode duct flow, check valve flow and piston gap flow, is achieved via the bond graph method. A prototype ER damper is then designed and manufactured on the basis of parameter analysis. The damping forces of the system are experimentally evaluated by changing the intensity of the electric field, the particle concentration and the electrode gap.

• Journal of the Korean Society for Heat Treatment
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• v.23 no.3
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• pp.137-141
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• 2010

The Co-Cr alloys have clinical histories in dental and orthopaedic implants, and recently in cardiovascular stent applications because the alloys exhibit a high elastic modulus and radiopacity. In order to improve mechanical property of the Co-Cr alloys, electropolishing is employed as the final process. Electropolishing, an anodic dissolution process in the transpassive state, is sensitively affected by process conditions such as current density, machining time, electrode gap. In this study, the effect of heat treatment conditions on surface roughness and inclusion analysis is investigated in Co-Cr alloy (L605). The most smooth surface of Co-Cr alloy is obtained when electropolishing is performed at 15-20 V for 15-30 sec with a electrode gap of 3.5 mm.