• The Transactions of the Korean Institute of Electrical Engineers
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• v.37 no.1
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• pp.63-68
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• 1988

The V-I characteristics of low pressure discharges occurring between each of three kinds of anode and a fixed hot cathode in several bi-cusp magnetic fields are investigated. The results are different from those in non-magnetic fields as follows` First, both breakdown and maintaining potentials of low pressure discharges in the fields are rather depend on the arrangement of the directions of magnetic lines of force and the directions between two electrodes than on the distance between two electrodes or the size of the electrodes. Second, the maintaining potentials of the discharges in the fields are lower than those in the non-fields, and the electrical conductivity in the fields are better than those in the non-fields. Third, the breakdown potertials in the fields when the direction of magnetic lines of force is perpendicular with the direction of discharging path between two electrodes are higher than those when the two directions are parallel with each other. But the maintaining patentials in the fields are shown the contrary phenomena with before. This results are particularily conspicuous as the separatrix of the fields pass across the discharging path between two electrodes.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.1462-1465
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• 2004

A new method to fabricate metal electrodes on side wall of the microchannel is presented. Coulter counter allows to count the number of cell passing through the microchannel by detecting impedance variation between two electrodes. The relative position of two electrodes is important for sensitivity of impedance measurement. 100nm thick Al electrodes are deposited on the channel side wall by means of shadow evaporation.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.55 no.9
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• pp.443-448
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• 2006

Non-contacting capacitive sensor based on Thompson-Lampard theorem have been fabricated and characterized for measuring of 때 order displacements. To overcome disadvantages of the existed capacitive sensors of parallel plate type with 2-electrodes and 3-electrodes, the developed new sensor was designed to have 4-electrodes with a constant gap of 0.2mm between the electrodes. Two of the electrodes were used as a high potential electrode and a low one, the other two electrodes were used as guard electrodes. These electrodes were made from copper using RF sputtering system on a sapphire plate with diameter 17 mm and thickness 0.7 mm. This sensor can be used for measuring the distance not only between the sensor and metallic target connected to ground potential but also non-metallic target without ground connection.

• KEPCO Journal on Electric Power and Energy
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• v.5 no.3
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• pp.197-200
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• 2019

We report on electrochemical signal amplification using gap electrodes based on the redox cycling between gap electrodes. The distance between electrodes was controlled from $2{\mu}m$ to a few hundreds of nanometer by chemical deposition of reduced Au ion on the pre-defined electrodes. Enhanced redox current of ferri/ferrocyanide was obtained by redox cycling between the two working electrodes. The faradaic current is amplified about a thousand times in this redox system. Since the signal amplification is due to the shortened diffusion length between the two electrodes, the narrower the nanogap was, the better detection limit, calibration sensitivity, and dynamic range. The experimental results were discussed on the basis of the cyclic voltammetry (CV), atomic force microscope (AFM) and scanning electron microscope (SEM) measurements.

• International journal of advanced smart convergence
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• v.4 no.1
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• pp.114-119
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• 2015

The different between two potential voltages can cause the electric field. The electric field is normally distributed along the radius of electrode, and hence it depends on the shape of electrodes. This paper analyses the distribution factor of electric field of symmetrical and asymmetrical concentric electrodes by using Finite Element technique. This allows an analysis the optimum safety clearance distance between two concentric electrodes. The symmetrical concentric electrode refers to Spherical-Spherical concentric electrodes and Cylindrical-Cylindrical concentric electrodes. It must be noted that the symmetrical electrodes are mostly applied for Gas Insulated Substation (GIS) equipments. The asymmetrical electrodes mention to Spherical (inner)-Cylindrical (outer) concentric electrodes and Cylindrical-Cube concentric electrodes, which present as the connection point of High Voltage (HV) cable. The simulations is also complies with the existing standards and regulations in order to ensure the accurate results.

• Journal of Sensor Science and Technology
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• v.19 no.1
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• pp.1-7
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• 2010

Electrostatic capacitance measurement method in a fine hose was proposed, in which two ring-type electrodes were disposed on the hose in the direction of fluid flow instead of the conventional face-to-face electrodes. With the proposed electrode structure, we realized a Ringer's solution exhaustion detector for an IV(invasive vein) injection set. On a 4 mm-diameter hose of IV set, we disposed two ring-type electrodes of 10 mm width at a distance of 5 mm each other and obtained 0.72 pF and 2.51 pF for air and 10 % dextrose Ringer's solution in the hose, respectively. The capacitance between the two electrodes varied with the hose-wraparound coverage of electrode as well as the width of electrode and the distance between the electrodes. For hose-wraparound electrode coverage of 75 %, the capacitance varied from 0.62 pF to 1.98 pF with the Ringer's solution level between the two electrodes. A charge amplifier converted the capacitance. variation into electric signal and a comparator was used to detect whether Ringer's solution was exhausted or not. The result was delivered to a host using a RF transmitter with 320 MHz carrier frequency.

• Journal of Advanced Marine Engineering and Technology
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• v.25 no.5
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• pp.1122-1129
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• 2001

Underwater wet arc welding process was experimentally investigated by using the six types of flux coated electrodes of 3.2 mm diameter and the KR-RA steel plate of 11 mm thickness as base metal. Two types of electrodes were domestic covered arc welding electrode(CR13, CR14) and another two types of wet welding electrodes(UWCS, TN20)were imported goods, and the other two type (UWX1, UWX2) were individually designed flux coated electrodes for experimental welding purpose. Main experimental results are summerized as follows: 1. It is ascertained that individually designed flux coated electrode(UWX1) could be used in practice with KR-RA steel plate for underwater wet arc bead welds. 2. Welding arc can be generated easily and considerably kept in stable using TN20 and UWX1 electrodes. 3. The micro Vickers hardness value and the portion of martensite in the HAZ were increased in all the electrodes by rapid cooling rate, but it is relatively maintain stable for UWCS, TN20 and UWX1 electrodes.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.768-771
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• 2001

Non-contacting capacitive sensor, based on principle of the cross capacitor, for measuring of $\mu\textrm{m}$-order displacements have been fabricated and characterized. To overcome disadvantages of the existed capacitive sensors of parallel type with 2-electrodes and 3-electrodes, the developed new sensor was designed to have 4-electrodes, two of them used high and low electrode the other two used as guard electrodes, on a sapphire plate with diameter 17 mm and thickness 0.7 mm, and are symmetrically situated with a constant gap of 0.2 mm between the electrodes. This sensor can be used for measuring the distance between sensor and target not only the metallic but also non-metallic target without ground connection.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.9
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• pp.1579-1583
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• 2008

We proposed the new structure of ac plasma display panel(PDP) to improve the luminous efficacy and driving voltage characteristics. Through two-dimensional numerical simulations, we analyzed the effects of new counter discharge type, which consists of counter sustain electrodes and auxiliary electrodes. Generally, an advantage of AC PDP with the counter sustain electrodes has been known for the driving characteristics of the low voltage. In this work, the new counter structure using the ignition discharge by the auxiliary pulse applied to the address electrode showed the result of the increased luminous efficacy. The short gap discharge between two auxiliary electrodes on the front plate could intensity the long gap discharge between counter electrodes. The reliability of simulation result could be confirmed by the experimental result in the test panel.

• Economic and Environmental Geology
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• v.14 no.3
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• pp.111-122
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• 1981

This study is a model analysis for an effective application of the geophysical prospecting to the investigation of geological structures or useful resources, and the purpose of it is to research a property of the electrical resistivity prospecting, especially by using a Three-Point electrode array method. In using the Three-Point electrode array method, it is theoretically assumed to choose the infinite for a distance between the two current electrodes, however it is impossible in applying to the practical field prospecting. Therefore this study was conducted for determination and presentation of a minimum appropriate distance between the two current electrodes by making a study on prospecting effect in the variation of distance between both the electrodes. In case that the ratios of the distance between the two current electrodes to that between the two potential electrodes are respectively chosen for 40, 400, 5,000, the experimental data of this study showed that the minimum appropriate distance between the two current electrodes is forty times as much as that between two potential electrodes. In order to make clear a problem about prospecting depth which is essential to the data processing, it had been chosen equally to the distance between two potential electrodes. As a result of it, it was shown that the anomaly is appeared along the position of an assumed ore body. Consequently it was found out that the prospecting depth of the Three-Point electrode array method is the same as the distance between the two potential electrodes. From the model experiment on the sheeting ore body(or linear structure) of horizontal, dipping of $30^{\circ}$, $60^{\circ}$ and vertical on the basis of above experimental condition, it was found out that the position and dip of assumed ore body could be inferred from the aspects of the equiresistivity curve. In consequence of performing out the simultaneous Normal and Reversal electrode movement, it was shown that the electrode movement of the Reversal forms the anomaly more clearly than that of Normal when the sheeting ore body is situated obliquely, therefore it could be ascertained that the electrode movement have to be performed simultaneously in the manner of Normal and Reversal. It was also exhibited that the aspect of the equiresistivity curve forms symmetrically when an assumed ore body (or linear structure) is situated horizontally or vertically, that is, symmetrically, and moreover that the aspect of the equiresistivity curve forms unsymmetrically when an assumed ore body (or linear structure) is situated obliquely. On the basis of these experimental analysis it is thought that it can be inferred from the aspect of equiresistivity curve whether an assumed ore body is obliquely situated or not.