• 대한화학회지
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• 제54권2호
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• pp.198-207
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• 2010

독스핀 하이드로클로라이드 선택전극의 구조와 성능특징에 대하여 개발하였다. 전극의 3가지 형태가 있다. I. 플라스틱 막 II. 코팅된 선형 III. 흑연으로 된 로드, 이것들은 암모늄 라이네케이트를 갖는 독스핀 하이드로클로라이드의 결합에 기초하여 구성되었다. 막의 조성, 가소제의 종류, 시험용액의 pH, 담궈 놓은 시간 그리고 전극에 있는 이질 이온들의 영향을 조사했다. $25^{\circ}C$에서 전극 I, II, III에 대해 각각 57.41 ${\pm}$ 0.5, 56.22 ${\pm}$ 0.2 and 52.88 ${\pm}$ 0.7 mV 의 평균 보정 그래프 기울기를 갖는 Nernst 반응을 보여준다. 그리고 전극 I, II, III에 대해 $1{\times}10^{-2}-1{\times}10^{-6}M$, $5{\times}10^{-2}-1{\times}10^{-6}M$ 그리고 $1{\times}10^{-3}-5{\times}10^{-6}M$의 독스핀 하이드로클로라이드 농도범위에 있고, $5.0{\times}10^{-7}M$, $6.3{\time}10^{-7}M$ 그리고 $2.5{\times}10^{-6}M$의 검출한계를 갖는다는 것을 보여준다. 만들어진 전극은 pH 3 - 7의 범위에서 선택적으로 정밀하고, 사용 가능한 평균을 보였다. 공통양이온, 알칼로이드, 설탕 아미노산, 그리고 약품첨가제로부터의 방해가 기록되었다. 제안된 전극에 의해 얻어진 결과는 약의 조세와 생물학적 유체에 있어서 약물의 확인에 성공적으로 적용되었다.

• 한국재료학회지
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• 제24권6호
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• pp.319-325
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• 2014

Cobalt nano-rods were fabricated using a template-free electrochemical-deposition process. The structure of cobalt electro-deposits strongly depends on the electrolyte composition and on the density of the applied current. In particular, as the content of boric acid increased in the electrolyte, deposits of semi-spherical nuclei formed, and then grew into one-dimensional nano-rods. From analysis of the electro-deposits created under the conditions of continuous and pulsed current, it is suggested that the distribution of the active species around the electrode/electrolyte interface, and their transport, might be an important factor affecting the shape of the deposits. When transport of the active species was suppressed by lowering the deposition temperature, more of the well-defined nano-rod structures were obtained. The optimal conditions for the preparation of well-defined nano-rods were determined by observing the morphologies resulting from different deposition conditions. The maximum height of the cobalt nano-rods created in this work was $1{\mu}m$ and it had a diameter of 200 nm. Structural analysis proved that the nano-rods have preferred orientations of (111).

• 조명전기설비학회논문지
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• 제19권6호
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• pp.67-74
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• 2005

접지 시스템은 전기설비의 기준 전위점을 확보할 뿐만 아니라, 대지에 낮은 저항으로 고장 전류를 흐르게 한다. 고장전류는 넓은 범위의 주파수를 포함하기 때문에 접지의 성능을 평가하기 위해선 주파수에 대한 함수로 접지임피던스에 대한 특성의 분석이 필요하다. 본 논문에서는 상용화된 접지봉(매직봉)의 접지임피던스를 0[Hz]에서 100[kHz] 범위까지 측정하였고, 접지임피던스를 회로 모델과 전달함수 모델로 구하여 측정된 값과 비교 검토하였다.

• 한국기계가공학회지
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• 제14권2호
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• pp.38-43
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• 2015

Tungsten inert gas (TIG) welding is commonly used in industries that require airtightness, watertightness, oiltightness, and precision. It is a non-consumable welding method that is commonly used for the welding of non-ferrous metals, but it can be used to weld most metals. The methods of TIG welding can be divided into three types. The first, manual welding is done directly on the metal by a welder with a torch. The second, semi-automatic welding, gets help from a material supplying machine, but it is conducted by a welder. Lastly, automated welding is conducted fully by a machine during its process and operation. Depending on the selection of electrode, the amount of heat that is applied to the base material and the electrode rod changes and makes the shape of welded parts different. A direct-current positive electrode was used for this study. Through the change of shielding gas type on a structural steel (SS-400) that is commonly used in industry, the composition and shape changes in welded parts were detected after welding. The heat-affected area, hardness value, and tensile strength were also identified through hardness testing and tensile testing. In this study, it was found that the higher hardness value of the heat-affected is, the weaker the tensile strength becomes.

• 전기학회논문지P
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• 제57권2호
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• pp.146-152
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• 2008

The frequency of lightning is increased due to improbable weather condition and global wanning. This phenomenon increases economical damage as well as human damage. Advanced countries like europe and north america have applied the facility standard of lightning by accumulating a store of quantitative data about lightning research. Lightning facility is composed of the lightning accepting part for induction lightning, ground connected electrode which conducts lightning current. The lightning accepting part is composed of normal rod, horizontal conductor, ESE lightning rod. Moreover, lightning accepting part is taken to use by the method of protection. This paper suggests HEC(Hybrid ESE-Conductor) method which mixes horizontal conductor and ESE lightning rod. This is also discovered by experiment that the starting point of corona discharge current is low, so it is efficient for lightning protection comparing with other methods. Moreover, distribution of electric field is analyzed qualitatively by finite element method. It also results in the relation of the starting point of corona discharge current. Corona discharge current makes minute current about some ${\mu}A$ between the electrodes by the strength of electric field. Also it occurs insulation destruction of gas, and it is developed to the shape of streamer by increase of the strength of electric field. We can find that the initial occurrence of streamer and contact probability of lightning can have advantage after researching the starting point of corona discharge current and discharge current of lightning striking point. This research demonstrates that the suggested HEC method is economically competitive as a lightning protection facility, and it takes a capably perfect role.

• 한국전기전자재료학회논문지
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• 제36권1호
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• pp.81-87
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• 2023

Heaters using the resistance heating principle are used in various industrial fields that require heat and are also essentially used in bidet among small home appliances. A planar heater and a coil-inserted heater mounted on a conventional commercially used bidet have disadvantages and limitations of complicated manufacturing process and local heating. In this study, silver-palladium (Ag-Pd) powder material was used for a screen-printing process that is more advantageous in achieving simplification than the existing process, and a rod-type heater for bidet was manufactured. The on-off cycle test under actual conditions was conducted to confirm the durability and the capability of the fabricated heater, and the fabricated heater operated more than 2,600 on-off cycles, which means it could be applied for a commercial product. In addition, through the on-off cycles under harsh conditions, the cause of failure was identified after the test that the durability limit temperature of the heater was 850℃. Through Ag-Pd rod heater in this study, it is expected to contribute to the efficient development of electrode materials for heaters and the improvement of the durability of heaters in the future.

• 한국화재소방학회논문지
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• 제16권1호
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• pp.30-38
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• 2002

가공 전력선로 아래에서 화재가 발생되면 전력선은 예기치 않은 섬락사고가 세계 여러나라에서 관측되고 있다. 본 연구에서는 화재의 발생으로 연소화염이 존재할 때, 주변 공기의 절연내력에 미치는 화염의 영향을 알아보기 위해 모의된 조건에서 여러 가지 실험을 행하였다. 침대평판, 구대평판 및 봉대평판 전극을 수직배치한 경우, 교류 및 직류 섬락전압 특성을 조사하였다. 실험결과, 구대평판 갭의 경우, d=1 cm 및 2cm일 때 교류섬락 전압의 상대값은 23.5% 및 30.4%이며, d=4cm인 경우는 37.8%인 것으로 나타났으며, 화염이 없는 경우에 비해 평균 33.0%인 것으로 나타났다. 직류전압 인가시는 화염이 없는 경우, 부극성의 섬락전압이 정극성보다 높았으나, 화염이 존재할 경우는 반대로 정극성이 부극성 전압보다 높은 것으로 나타났다.

• Journal of Electrochemical Science and Technology
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• 제11권4호
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• pp.384-391
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• 2020

Due to its characteristics of light weight, high energy density, good safety, long service life, no memory effect, and environmental friendliness, lithium-ion batteries (LIBs) are widely used in various portable electronic products. The capacity and performance of LIBs largely depend on the performance of electrode materials. Therefore, the development of better positive and negative materials is the focus of current research. The application of metal organic framework materials (MOFs) derivatives in energy storage has attracted much attention and research. Using MOFs as precursors, porous metal oxides and porous carbon materials with controllable structure can be obtained. In this paper, rod-shaped Co-MOF-74 was grown on Ni Foam (NF) by hydrothermal method, and then Co-MOF-74/NF precursor was heat-treated to obtain rodshaped Co₃O₄/NF. Ni Foam was skeleton structured, which effectively relieved. The change of internal stress changes and destroys the structural volume of the electrode material and reduces the capacity attenuation. Co₃O₄/NF composite material has a specific discharge capacity of up to 1858 mA h/g for the first time, and a reversible capacity of up to 902.4 mA h/g at a current density of 200 mA/g, and has excellent rate and impedance performance. The synthesis strategy reported in this article opens the way to design high-performance electrodes for energy storage and electrochemical catalysis.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 하계학술대회 논문집 C
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• pp.1326-1329
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• 1995

An influences of gap clearance, pressure and applied voltage shape on breakdown characteristics are investigated by using a rod-to-plane electrode in $SF_6$ gas. In case of D.C and A.C, a corona stabilization effect increases the breakdown voltage remarkably for lower pressure than 0.2MPa, whereas incase of negative D.C this effect exists independently of gas pressure. This suggests that an insulation optimization in a pratical apparatus is needed to prevent a corona appearance through the removal of local field enhancement.

• 한국자동차공학회논문집
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• 제4권6호
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• pp.52-64
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• 1996

This paper presents an active position control of a single-rod cylinder system featuring an electrorheological(ER) fluid-based valve. The ER fluid consisting of silicone oil and chemically treated particles is firstly composed and its Bingham property is tested as a function of imposed electric field. A multi-channel plate type of ER valve is then designed and manufactured on the basis of the field-dependent Bingham model. Performance test of the ER valve is undertaken by evaluating pressure drop with respect to the number of electrode as well as the intensity of the electric field. Subsequently, the ER valve-cylinder system is constructed and its governing equation of motion is derived. A neural control scheme for position control of the cylinder is formulated by incorporating proportional-plus-derivative(PD) controller and implemented. Experimental results of both regulating and tracking control responses are presented in order to demonstrate the efficacy of the proposed ER valve-cylinder control system.