• Journal of the Microelectronics and Packaging Society
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• v.7 no.1
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• pp.29-34
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• 2000

In this paper, the damping characteristics for electrostatically driven micro mirror which have deep grooves on their driving electrodes were investigated. A coupled simulation of gas flow and structural displacement of the micro mirror using the Finite-Element-Method is applied to this. The damping farce is caused by squeeze action of the gas film between a moving mirror plate and the electrodes. The grooves decrease the damping force and enable the moving plate to be driven at high speed and low driving voltage.

• Korean Journal of Environmental Agriculture
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• v.18 no.4
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• pp.332-338
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• 1999

To treat livestock wastewater effectively by electrochemical method using a stainless steel electrode or au aluminum electrode, the effects of voltage, distance of electrodes and PACS(Poly Aluminum Chloride Silicate) dosage on removals of pollutants in batch experiment for investigation the optimum treatment conditions of livestock wastewater were investigated. The results were summarized as follows ; On the effect of voltage, temperature and pH in electrochemical reactor were increased with increase in voltage but EC was a reverse in both electrodes. Removals of COD and T-N were increased with increase in voltage in both electrodes. SS removal was greater than 90% regardless of voltage without doing electrochemical reaction over 15min at 20V or 12min at 30V in both electrodes. T-P removal was over 90% regardless of voltage in both electrodes. On the effect of distance between two electrodes, removals of COD, T-N and T-P were increased with closeness in distance between two electrodes, and SS removal was greeter than 90% regardless of distance between two electrodes in both electrodes. On the effect of PACS dosage, removals of COD, T-N and T-P were increased with increased in PACS dosage up to 200㎎/l in both electrodes. SS removal was greater than 90% regardless of PACS dosage in both electrodes.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.7 no.1
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• pp.36-39
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• 2014

MFC(microbial fuel cell) is the device to produce the electricity by using the microbes which are living in the waste water. In this paper, the electric characteristics of the MFC were investigated according to each different structure and electrode materials. The voltage being reversed phenomenon was observed in the MFC which uses the cupper plate as the cathode material. This result comes from the oxidation reaction of the cupper plate electrode in this MFC. And this MFC has lower output voltage than one that has a platinum plate electrode. The smaller gap distance of the cupper plate electrode of the MFC showed the higher output voltage. The larger electrode area of the cupper plate electrode showed that the reaching time of the output voltage to the maximum value was delayed.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.11
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• pp.815-820
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• 2013

The purpose of this research is to prepare the aluminum electrode coated with activated carbon for removing air pollution dust. The experiments were studied on the selection of optimal polymer for binding aluminum plate with powdered activated carbon, preventing the pore blocking of activated carbon from polymer binder, and the dust treatability for the prepared activated carbon electrode. The optimal adhesive for coating activated carbon on an electric aluminum plate was polyvinyl acetate (PVA) with vinyl functional group. For the opening of the blocked pore with polymer, it was very effective to embed polymer solvent in pore of activated catbon firstly before mixing activated carbon with PVA, and then to devolatilize the embedded solvent of carbon pore at high temperature. The mass of trapped dust on aluminum electrode coated with activated carbon was about double of the trapped one on just aluminum electrode.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.422.2-422.2
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• 2016

스마트폰, 태블릿 등의 디바이스의 발전에 따라 휴대성이 매우 중요해졌다. 디바이스의 크기, 두께, 유연성에 관한 연구가 활발히 진행되고 있으며, 그 중에서도 energy storage device의 flexibility를 향상시키는 연구가 주목 받고 있다. Energy storage device의 성능 향상을 위해서는 power density를 높여야 하며 flexibility를 위해서는 전극판과 전극소재 간의 부착력을 증가시켜야 한다. 본 연구에서는, power density와 소재 간의 부착성을 개선시키기 위해 기존 graphene보다 표면적이 넓으며 power density가 좋고 전극판과의 부착성이 좋은 hybrid GNP-CNT를 사용하였다. 그리고 Ag NWs/CNT PET film 을 사용하여 전도성이 있는 flexible한 전극판을 사용하였다. SEM 측정을 통해 표면 분석을 하였고, sample에 패턴을 하고 Bending test를 하여 부착성을 확인하였다. 또한, CV curve를 측정하여 supercapacitor의 특성을 확인하였다. 향후, $MnO_2$ NWs를 hybrid GNP-CNT에 합성시킴으로 energy storage device의 energy density를 더욱 향상시키는 연구를 진행할 것이다.

• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.2266-2268
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• 2000

본 논문에서는 스캐닝 미러의 일종으로, 광저장 장치의 픽업헤드용으로 미세회전을 하면서 레이저 빔을 편향시키는 용도로 사용되는 미러를 제작하고 구동실험을 하였다. 제작된 미러의 크기는 $2400{\times}2400{\times}64{\mu}m^3$이고, 빔 스프링은 $500{\times}9.6{\times}64{\mu}m^3$이다. 니켈 전해 도금으로 29${\mu}m$ 높이의 구동 전극을 제작하였고(세가지 모델: 공기통로가 없는 전극, 공기통로와 간격이 각각 200${\mu}m$인 전극, 공기통로와 간격이 각각 100${\mu}m$인 전극), 미러판과 전극을 조립하여(미러판과 전극 사이의 간격은 각각 29${\mu}m$, 26${\mu}m$, 26${\mu}m$) 구동실험을 하였다. 공진 주파수의 계산간은 576Hz, 측정값은 3개의 미러에서 모두 568Hz이었다. 전극과 미러판의 간격이 최대 접근거리 18${\mu}m$가 되도록 미세 회전을 시켰을 때, 공기통로가 없는 전극에서는 공진 주파수가 524Hz, 공기통로가 200${\mu}m$인 전극에서는 544Hz로 각각 감쇠되었고, 공기통로가 100${\mu}m$인 전극에서는 그대로 568Hz이었다.

• 전기의세계
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• v.11
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• pp.56-61
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• 1963

현재 우리나라에서 사용하고 있는 접지전극은 30*30$cm^{2}$의 넓이와 0.7,0.9,1.0,2.0mm의 동판전극들이다. 인건비가 비싸고 전극 자료비가 우리나라에 비하여 싼 외국에서는 접지봉을 많이 사용하고 있다. 접지봉을 사용하면 인건비는 적게들지만 매설하기 위한 기계의 시설비와 같은 접지저항치를 얻기 위한 동량이 판전극 사용시보다 더욱 많이 필요하므로 우리나라 현사정에는 부적당하다. 본 연구의 목적은 소요접지저항을 얻는데 동판전극보다 더욱 경제적인 접지방식을 모색하여 이것과 동판전극방식과의 기술적, 경제적비교검토를 하는데 있다.

• Proceedings of the KIEE Conference
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• 2004.11a
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• pp.29-32
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• 2004

외부전극 형광램프의 구동에서 과도한 전력을 인가하면, 치부전극 부분의 유리관 표면에 작은 원형의 구멍이 발생하여 램프가 파손된다. 이를 핀홀이라고 지칭한다. 핀홀은 치부전극과 유리관을 유전층으로 하는 캐패시터의 절연파괴로 분석된다. 치부전극에 정상 동작이상의 고 전압을 인가하면, 고 전류에 의하여 전극부분에 상당한 열이 발생하고, 이러한 전극부분에 발생하는 열과 고 전압에 의한 유리층 자제의 강한 전기장에 의하여 절연이 파괴되면서 핀홀이 발생한다. 이러한 현상은 유리판을 절연층으로 하여 유리판 양면에 전극을 형성하여 고 전압에 의한 절연 파괴 실험과 동일한 현상으로 이해된다.

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.1
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• pp.90-100
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• 1993

A finite element formulation of vibration control of a laminated plate with piezoelectric sensor/ actuators is presented. Classical lamination theory with the induced strain actuation and Hamilton's principle are used to formulate the equations of motion of the system. The total charge developed on the sensor layer is calculated from the direct piezoelectric equation. The equations of motion and the total charge are discretized with 4 node, 12 degrees of freedom quadrilateral plate bending elements with one electrical degree of freedom. The mass and stiffness of the piezoelectric layer are introduced by treating them as another layer in laminated plate. Piezoelectric sensor/actuators are distributed, but discrete due to the geometry of electrodes. By defining an i.d. number of electrode for each element, modelling of electrodes with variable geometry can be achieved. The static response of a piezoelectric bimorph beam to electrical loading and sensor voltage to given displacement are calculated. For a laminated plate under the negative velocity feedback control, the direct time response by the Newmark-.betha. method and damped frequencies and modal damping ratios by modal state space analysis are derived.

• Korean Chemical Engineering Research
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• v.45 no.2
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• pp.190-196
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• 2007

This study examined the nitrate removal efficiency which uses an electrowinning, and also analyzed the nitrate removal efficiency under a variety of operating conditions such as nitrate concentrations, pH, current densities, electrodes, reducing agents in order to determine optimal conditions. In addition, the multi-step electro-chemical process test has been also analyzed. During the electrowinning, the identical Zn-Zn and Pt-Ti electrodes in the insoluble oxidation electrode(Pt) has shown the highest nitrate removal efficiency in the 100 mg $NO_3^{-}$ -N/L concentration. In the concentration of 150 mg $NO_3^{-}$ -N/L, the efficiency of the Zn-Zn electrode were 70~85%, and that of Pt-Ti electrode were 40~50% without any change of pH. In the high concentration of 500 and 1,000 mg $NO_3^{-}$ -N/L, the higher the concentration, the more decrease of its nitrate removal efficiency decreased. However, the energy consumed for nitrogen removal increased when the nitrate concentration was high. As a result of the multi-step electro-chemical process test, We chose the Test 4. Because the first, most of the zinc consumed from 1 step was recovered from over the 2 step. The second, amount of consumption anode decreased with insoluble anode Pt from over the 2 step. And the third, Zn cathode increased the possibility of reusing Zn deposited. In view of the results so far achieved, the multi-step electro-chemical process would be applied to treat nitrogen involved in metal finishing wastewater.