• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 추계학술대회 논문집
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• pp.421-424
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• 2000

We have examined the impedance characteristics and the rate characteristics of LPB. As results, the impedance of LPB decreased with increased pressing rate of electrodes, adding amounts of PVdF and VGCF. And the rate characteristics of LPB increased with the a increase of pressure-rate, PVdF and VGCF contents. The rate characteristics of LPB was improved by pressing of electrode and adding of VGCF content. And specific capacity of anode was increased with adding amounts of PVdF. Higher pressing rate of electrodes, higher adding amounts of PVdF and VGCF was necessitated good rate characteristics for lithium polymer battery.

• 기술사
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• 제14권4호
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• pp.15-25
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• 1981

Electrical behaviors of the divalent silver oxide-zinc cell were analyzed for imporving capacity and keeping electrodes from passivation or sharp increases of cell internal resistance in the course of discharge. One of primary factors in relation to lowering performance can be depicted by cell internal resistance increase being created by various routes, first by insufficiency and/or the carbonation of the electrolyte, secondly by barrier blockage, thirdly by electrode passivation which are due to improper material use of wrong processing, and by gassing as fourth cause. The carbonation causes electrobyte to have impedance up as well as poor amalgamation, resulting in vigorous corrosion reaction of copper plated inner top, evolving hydrogen gas. Electrical characteristics of the cell was reviewed to elucidate relationships between the discharge capacity and the cell internal resistance.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.69-70
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• 2006

In lithium-ion batteries, separator membrane's, main role is to physically isolate a cathode and an anode while maintaining rapid transport of ionic charge carriers during the passage of electric current. As far as battery safety is concerned, the electrical isolation of electrodes is most crucial since unexpected short-circuits across the membrane induces hot spots where thermal runaway may break out. Internal short-circuits are generally believed to occur by protrusions on the electrode surface either by unavoidable deposits of metallic impurities or by dendritic lithium growth during battery operation. Another cause is shrinkage of the separator membrane when exposed to heat. If separator membrane can be engineered to prevent the internal short-circuit, it will not be difficult to improve lithium-ion batteries' safety. Commonly the separators employed in lithium-ion batteries are made of polyethylene (PE) and/or polypropylene (PP). These materials have terrible limitations in preventing the fore-mentioned internal short-circuit between electrodes due to their poor dimensional stability and mechanical strength. In this study we have developed a novel separator membrane that possesses very high thermal and mechanical stability. The cells employing this separator provided noticeable safety improvement in the various abuse tests.

• 조명전기설비학회논문지
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• 제15권3호
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• pp.25-34
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• 2001

본 논문에서는 방전관을 채용하여 전기적 기체방전의 중침을 이용한 새로운 방전형식의 환경개선용 오존발생 기술을 개발하였다. 방전관형 오존발생기(DLO)는 설치된 3개의 전극중 접지전극인 중심전극으로 방전관을 사용 하였으며, 나머지 2개의 메쉬형 내부전극과 나선형 외부전극에 180[$^{\circ}$]의 위상차를 가진 2개의 교류고전압 전원을 인가함으로써 방전관과 내부전극, 방전관과 외부전극사이의 방전공간에서 각각 발생되는 무성방전의 중침에 의하여 오존이 발생되는 구조이다. 이때, 원료가스의 유량, 방전전력 및 DLO의 사용 개수 변화에 따른 방전특성과 오존생성특성을 연구검토하였으며, DLO로부터 생성된 오존을 대기오염물질인 NO 가스에 접촉시켰을 때 NO 제거특성이 우수하여 방전관형 오존발생기가 대기환경개선 설비로 적용가능함을 확인하였다.

• Journal of Electrochemical Science and Technology
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• 제14권2호
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• pp.184-193
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• 2023

This study investigates the effects of a carbon fiber layer formed on the surface of an etched aluminum current collector on the electrochemical properties of the activated carbon electrodes for an electric double layer capacitor. A particle size analyzer, field-emission SEM, and nitrogen adsorption/desorption isotherm analyzer are employed to analyze the structure of the carbon fiber layer. The electric and electrochemical properties of the activated carbon electrodes using a carbon fiber layer are evaluated using an electrode resistance meter and a charge-discharge tester, respectively. To uniformly coat the surface with carbon fiber, we applied a planetary mill process, adjusted the particle size, and prepared the carbon paste by dispersing in a binder. Subsequently, the carbon paste was coated on the surface of the etched aluminum current collector to form the carbon under layer, after which an activated carbon slurry was coated to form the electrodes. Based on the results, the interface resistance of the EDLC cell made of the current collector with the carbon fiber layer was reduced compared to the cell using the pristine current collector. The interfacial resistance decreased from 0.0143 Ω·cm² to a maximum of 0.0077 Ω·cm². And degradation reactions of the activated carbon electrodes are suppressed in the 3.3 V floating test. We infer that it is because the improved electric network of the carbon fiber layer coated on the current collector surface enhanced the electron collection and interfacial diffusion while protecting the surface of the cathode etched aluminum; thereby suppressing the formation of Al-F compounds.

• 전기학회논문지
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• 제56권5호
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• pp.910-914
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• 2007

Recently, a study on the energy conversion efficiency and up sizing' technology of dye-sensitized solar cell (DSC) which is focused in considering a new alternative solar cell has been executed. But consideration for the cell characteristics about an internal electronic flow on a large-scaled DSC has not been carried out yet. In this study, we have chosen a solar cell width as a variable of a large-scaled DSCs and confirmed electric characteristics of an individual cell. First, Pt counter electrode surface of DSC is deposited by RF sputtering methode and the electrochemical properties of Pt electrodes was investigated by cyclic -voltammetry. With the Pt electrode, we fabricated DSC samples of different width. As a result, the higher the internal resistance of DSC becomes, the wider the width gets. Internal resistance makes it difficult to collect photoelectron generated from dye. Ultimately up sizing DSC causes the increase of internal resistance and then has a bad effect on the cell characteristics.

• 한국임상수의학회지
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• 제28권1호
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• pp.128-132
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• 2011

Holter monitoring has been recognized as an useful noninvasive instrument for monitoring the cardiac electrical activity over 24 to 48 hours. Because the surface electrocardiogram (ECG) is recorded only for several seconds to minutes, it often misses or underestimates the underlying arrhythmia. The surface ECG is also easily influenced by depolarization potentials from skeletal muscle by the movement of patient (especially muscle tremor). However, holter monitoring is less affected by such factors. There has been no precedential report in veterinary medicine applying digital holter monitor with unipolar precordial chest lead using 4 electrodes. This article describes its clinical indications, equipment and technical application method in dogs.

• 한국수소및신에너지학회논문집
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• 제24권5호
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• pp.401-412
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• 2013

The paper is to study on the simulation of the micro/macroscale thermo-electrochemical model of a single cell of anode-supported SOFC with direct internal reforming. The coupled heat and mass transport, electrochemical and reforming reactions, and fluid flow were simultaneously simulated based on mass, energy, charge conservation. The micro/macroscale model first calculates the detailed electrochemical and direct internal reforming processes in porous electrodes based on the comprehensive microscale model and then solve the macroscale processes such as heat and mass transport, and fluid flow in SOFCs with assumption of fully-developed flow in gas channel. The simulation results evaluate the overall performance by analyzing distributions of mole fraction, current density, temperature and microstructural design in co/counter flow configurations.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 E
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• pp.2259-2261
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• 1999

In this paper, an ozonizer, which can generate individual and superposed silent discharge, using three-phase voltage has been designed and manufactured. The ozonizer consists of 3 electrodes(Central Electrode, Internal Electrode and External Electrode) and 2 gaps(gap between Central Electrode and Internal Electrode, gap between Internal Electrode and External Electrode). Ozone is generated according to voltage supplying method to each electrode by individual silent discharge and three-phase superposed discharge. The characteristics of ozone generation were investigated with variation of discharge power and the quantity of supplied gas($O_2$). In case of individual silent discharge, the maximum values of ozone concentration, ozone generation and ozone yield were obtained between internal electrode and external electrode, and its values were 2300[ppm], 570[mg/h] and 745[g/kWh] respectively. Each maximum values was 5039[ppm], 1773[mg/h] and 851[g/kWh] respectively, when three-phase superposed silent discharge was employed. Therefore, characteristics of ozone generation with three-phase voltage are improved compared with single-phase voltage because silent discharge is generated continuously.

• 조명전기설비학회논문지
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• 제19권5호
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• pp.87-93
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• 2005

본 논문에서는 고농도$\cdot$고수율 오존발생기를 개발할 목적으로 망사형 내부전극과 무성방전의 중첩을 이용한 중첩방전형 오존발생기를 설계$\cdot$제작하였다. 중첩방전형 오존발생기는 방전공간에 3개의 전극(중심전극, 내부전극 및 외부전극)과 2개의 gap(중심전극과 내부전극 사이의 gap과 내부전극과 외부전극 사이의 gap)으로 구성되어있다. 중첩방전형 오존발생기의 중심전극을 공통접지하고 내부전극과 외부전극에 $180{[^\circ]}$의 위상차를 가진 역극성의 교류 고전압을 각각 인가하면 각각의 방전 gap에서 발생하는 무성방전이 중첩되면서 오존이 발생된다. 이때, 내부전극의 조밀도가 증가할수록 방전전극의 면적이 확대되고 방전공간의 전력밀도가 억제되어 오존생성특성이 상승하였다. 그 결과 최대 17,720[ppm], 5.4[g/h] 및 250[g/kwh]의 오존을 얻을 수 있었다.