• 조명전기설비학회논문지
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• 제14권2호
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• pp.68-74
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• 2000

본 논문에샤는 동축형 전극구조 변화시의 중첨방전에 의해 발생되는 오존의 농도 효율 및 발생량 특생에 대해서 논했다. 오존생정올 향상시키기 위해 오존방전환의 새로운 형태를 제안하였으며 연면방전과 무성방전이 동시에 분리된 방전공간내에서 발생하도록 하였다. 전극구조에 대한 오존발생 의존성을 조사하지 워해 구조가 다른 형태(2전극-1캡,3전극-2캡 및 3전극-3캡형)인 방전관올 설계.제작하였고 실험은 오존발생특성을 살펴보지 위하여 60[Hz] 전원을 사용하여 무성방전과 연면반전을 같은 갭내에 중첩시켜 측정한 결과 무성방전을 이용한 전극구조보다 중첩방전올 이용한 전극에서 오존의 농도, 효율 및 발생량이 향상됨율 확인할 수 있었다.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2004년도 제3회 금형가공 심포지엄
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• pp.255-259
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• 2004

3-D micro structures and micro tools are fabricated using MEDM (Micro Electric Discharge Machining). To make micro structures, micro electro discharge milling process is applied. During micro electro discharge milling, electrode (tool) wears both axial and radial direction. To compensate tool wear which influences significantly machining accuracy, overlap machining path is proposed. Machining characteristics of micro electro discharge milling is investigated in considering of depth of cut and capacitance of discharge circuit. Micro complex shaped tools are fabricated using REDM (reverse electro discharge machining). Sacrificial electrode is machined through electro discharge milling process and is used as electrode to make micro tools. Using this process several micro tools shape of 'ㄷ', 'ㅁ' and 'o' are fabricated. With these complex shaped tools, micro machining is successfully applied repeatedly.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제48권12호
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• pp.791-797
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• 1999

Recently the ozone generation system is well used for cleaning the contaminated water by using the strong oxidization effects of ozone. In this paper the concentration, yield and generation quantity of the ozone by the Surface-Silent Discharge According to the Length of Coaxial Electrode is described. The electrodes composed of 3 electrodes-2 gaps are coaxial type and the ozone generation tube were designed and fabricated from the point of view of the energy efficiency, stability and easy control. To investigate the ozone generation dependency on electrode length, a few discharge tubes with different lengths were fabricated. The experimental equipments were provided with cooling system and dehumidifier for the many testing conditions. The main results show that the concentration, yield and generation quantity of ozone are improved by decreasing gas temperatures and increasing electrode lengths.

• International Journal of Precision Engineering and Manufacturing
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• 제9권1호
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• pp.3-6
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• 2008

Electrical discharge machining (EDM) is one of the most widespread nonconventional machining processes. Recently, a low-power micro-EDM process was introduced using a cylindrical electrode. Since its development, micro-EDM has been applied effectively to micromachining, and because the device setup for this process is simple, it is suitable for a microfactory that minimizes machines to fabricate small products economically in one system. In the EDM process, however, the electrode is also removed along with the workpiece. Therefore, the electrode shape and length vary as machining progresses. In this paper, a control method using a high speed realtime voltage measurement is proposed to regulate the rate and amount of material removed. The proposed method is based on the assumption that the volume of the workpiece removed in a single discharge pulses is nearly constant. The discharge pulses are monitored and controlled to regulate the amount of material removed. For this purpose, we developed an algorithm and apparatus for counting the number of discharge pulses. Electrode wear compensation using pulse number information was applied to EDM milling in a microfactory, in which a slight tilt of the workpiece may occur. The proposed control method improves the machining quality and efficiency by eliminating the inaccuracies caused by electrode wear and workpiece tilt.

• 한국수소및신에너지학회논문집
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• 제6권1호
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• pp.35-41
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• 1995

The MmNi-based alloy electrode was studied for use as a negative electrode in Ni-MH battery. Alloys with $MmNi_5-_xM_x$(M=Co,Al,Mn) composition were synthesized, and their electrode charateristics of activation rate, temperature dependence, electrode capacity and cycle life were investigated. With increasing Al content and decreasing Mn content in the alloys, the discharge capacity increased while the cycle life decreased. As x in $MmNi_5-_xM_x$ increased from 1.5 to 2.0, decreasing the Ni content, the discharge capacity, the low temperature property and the rate capability decreased. However its cycle life was improved. Increasing Co content resulted in a prolonged cycle life and decrease of high rate discharge capacity. It can be concluded that the most promising alloy in view of discharge capacity and cycle life is $MmNi_{3.5}Co_{0.7}Al_{0.5}Mn_{0.3}$.

• 조명전기설비학회논문지
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• 제20권4호
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• pp.37-42
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• 2006

본 논문에서는$CO_2$를 발생시키지 않고 물로부터 직접 수소를 제조하기 위하여 비열플라즈마를 이용하였다. 다중침-평판형(Multineedle-plate electrode geometry reacto: MPER)과 단일침-평판형(Needle-plate electrode geometry reactor: NPER) 두종류의 수소제조 반응기를 설계 제작하여 수소 발생에 미치는 영향에 대하여 실험하였다. 수소발생을 높이기 위해서는 강한 아크성 스트리머 방전 발생과 효과적인 수표면 방전을 위한 수표면 조건을 고려해야만 된다.

• 한국대기환경학회지
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• 제14권3호
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• pp.237-250
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• 1998

In this study, the characteristics of electrostatic bag filter to overcome the main problems such as the high pressure drop and low collection efficiency for submicron particles are investigated with the experimental parameters. Especially, the experiment is carried out focusing on collection efficiency and pressure drop change mechanism as a function of discharge electrode shapes and filter properties, including the applied voltages, filtration velocities and particle concentrations, etc . Results show that the collection efficiency is improved over 30% for the fine particle below 1 pm and pressure drop reduction ratio (PDRR) increases in the following order 4 mm screwy > 4 mm square > 4mm round discharge electrodes . For the filter properties, Nomex is more effective than PE under the influence of electrostatic force. Applying 30 kV for a screwy discharge electrode, higher overall collection efficiency is maintained in spite of the increment of filtration velocity over four times (8 m/min) in comparison with that of 2 m/min and PDRR are highly shown over 80o1o with various filtration velocities, 5, 8, 11 m/min.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제48권2호
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• pp.133-140
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• 1999

The relationships between discharge characteristics and sustain electrode shape are studied in AC PDP by calculating the electric field and measuring discharge voltage, luminance and current. The maximum electric field is obtained for the triangle shape electrode. It is 1.8 times larger than uniform electric field type. It has been shown thatthe firing voltage is largely affected by the degree of electric field concentration. But, as the difference of the maximum and minimum value of electric field in a cell increases, the luminance and luminance efficiency decrease. And, the charge variation during discharge is proportional to the area of electrode.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 추계학술대회 논문집 Vol.19
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• pp.162-163
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• 2006

XLPE is used to insulator for Ultra High Voltage power cable. It is easy to processing also has a good insulating property. The study for diagnosis of lifetime and improvement is proceeding continuously. In this paper, it is investigated partial discharge distribution according to slope of needle electrode 0, 20, $40^{\circ}$. Applied voltage is 0.5 [kV/s] by step form for inception voltage. As the result of study, we conformed that increase of slope led to reduce of discharge number and total discharge quantity.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 영호남 합동 학술대회 및 춘계학술대회 논문집 센서 박막 기술교육
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• pp.82-85
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• 2006

As a display becomes large recently, Acquisition of high luminance and Luminance uniformity is becoming difficult in the existing CCFL or EEFL backlight system. So, study for a performance enhancement has enforced. but lamp development of flat type is asked for high luminance and a luminance uniformity security in of LCD and area anger trend ultimately. In this paper, we changed a tip shape of an electrode for production by the most suitable LCD backlight surface light source, and confirmed discharge characteristic along discharge gas pressure and voltage, and confirmed electric field distribution and discharge energy characteristic through a Maxwell 2D simulation. Therefore the discharge firing voltage characteristic showed a low characteristic than a rectangular type and round type in case of electrode which used tip of a triangle type, and displayed a discharge electric current as a same voltage was low.