• The Journal of Korean Institute of Communications and Information Sciences
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• v.23 no.4
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• pp.836-845
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• 1998

In this ppaer, the confguration of multi-layers of the image planes surrounding the current trace of inite width has been considered, and the shielding performance of image planes is analyzed with the parameters of the width and conductivity of the planes, and the distance between the current trace and the planes. The induced current distributions on the image planes have bgeen calculated by solving a set of electric field integral equations by the method of moments. To cacluate the current distribution on the planes effectively, a new method for dividing integral intervals is proposed.

• 전기의세계
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• v.30 no.4
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• pp.231-236
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• 1981

It has been known that D.C. breakdown Voltage is lower than A.C. breakdown Voltage in insulatingoil, but there are still many unvivid points at electric conduction in breakdown or under of high electric field. This study measured the electric current-electric field characteristics (I-E characteristics) and the breakdown Voltage under of D.C. electric field of insulating oil using the system of electrodes that are near the Uniform electric field with a result. I can study, electric conduction in area of high electric field depends upon the Schottky effect. The liquidity of breakdown electric field takes place by the local concentration of electric field. The longer gap is and the more electric current is the more breakdown Voltage decreased. There are not almost the change of electric current-electric field characteristics by materials of electrode.

• The Korean Journal of Ceramics
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• v.6 no.3
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• pp.262-266
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• 2000

We investigated the effect of the grain size on the photovoltaic current in (Pb$_{1-x}$La$_x$)TiO$_3$ceramics, and the photoinduced domain switching in (Pb$_{0.85}$La$_{0.15}$)TiO$_3$and BaTiO$_3$ceramics. These behaviors in ferroelectric ceramics were attributed to the grain boundary at which photoexcited electrons were trapped. As the charged grain boundary acted as an electro-potential barrier which impeded the movement of electrons, the photovoltaic current showed a peak at a critical grain size. The space charge field built by the electrons trapped at the grain bound-aries was accounted for the photoinduced domain switching, and AE experimental results support well this account.

• Journal of the Korean Ceramic Society
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• v.40 no.10
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• pp.921-924
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• 2003

A current-voltage relation for Positive Temperature Coefficient of Resistance (PTCR) ceramic was derived and compared with the experimental data. The new current-voltage relation was developed based on Heywangs double Schottky barrier model and a bias distribution across the grain boundary. The voltage limitation V < 4${\Phi}$$\sub$b/ suggested by Heywang is no longer necessary in the new expression for the voltage dependence of the resistance. The pulsed voltages were applied to the PTCR ceramic specimen in order to avoid possible temperature variation during the measurement.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.04a
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• pp.11-13
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• 2002

The performance of DC current sensor based on giant magnetoimpedance (GMI) effect in amorphous ribbon has been tested. The ribbon after field annealing shows the maximum GMI ratio of 30 % at 100 kHz measuring frequency. In the sensor element of sample wound the circular form, GMI ratio and sensitivity are decreased due to internal stress. The sensor voltage output increases with applied DC current up to 1 A with a good linearity, of which direction can be known due to asymmetric characteristics.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.05c
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• pp.47-50
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• 2001

Conventionally, air-cored Rogowski coil was designed for use as high alternating and transient current sensor without saturation caused by ferromagnetic material in its core. This paper investigated that Rogowski coil can be applied to low current measurement in 60Hz power line. Measured parameters R, L of coil were compared with theoretically calculated values. Output voltages crossed by Rogowski coil have shown some linearity according to input current(tens to thousands of amperes) passing through it. And also shielding effect for external noises was investigated for three cases.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2013.05a
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• pp.179-179
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• 2013

Surface resistance of electro-deposited copper with its thickness, current density and surface roughness was determined by using a 4-point probe analyzer. The copper was prepared electrochemically on 316 stainless steel substrate in copper sulfate solution at the condition of $1A/dm^2$, 298 K, and 6.5 cm-electrode distance. The surface resistance of the copper sheet in the range of $0.93-0.97{\Omega}$ increased with the copper thickness in the range of $21-70{\mu}m$. The surface resistance in the range of $0.963-1.009{\Omega}$ also increased with current density in the range of $0.5-2A/dm^2$. The increased surface resistances corresponded to 11% for thickness and 25% for current density, respectively.

• Journal of the Korean institute of surface engineering
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• v.18 no.4
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• pp.164-183
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• 1985

The microstructure of the zinc electrodeposits was investigated by changing the flow rate of electrolyte in zinc sulfate Bath. The cathode current efficiency increased with increasing flow rate of electrolyte. The preferred orientation of zinc electrodeposit changed from (11.2) texture to (10.3) or (10.1)+(10.2) texture with increasing current density in the range of flow rate, 0.2-1.2m/sec. The morphology of the deposits changed from the sponge deposit to the blocks of hexagonal crystallites packed together through the structures of find polycrystallite with increasing current density. The microstructure of the cross-section of the above deposits are granular structure and columnar structure respectively. The surface roughness of zinc electrodeposits decreased with increasing current density and flow rate of electrolyte.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.33A no.4
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• pp.129-135
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• 1996

In this paper, the hot carrier effect and device degradation of deep submicrometer SC-PMOSFETs have been measured and characterized. It has been shown that the substrate current of a 0.15$\mu$m PMOSFET increases with increasing of impact ionization rate, and the impact ionization rate is a function of the gate length and gate bias voltage. Correlation between gate current and substrate current is investigated within the general framework of the lucky-electron. It is found that the impact ionization rate increases, but the device degradation is not serious with decreasing effective channel length. SCIHE is suggested as the possible phusical mechanism for enhanced impact ionization rate and gate current reduction. Considering the hot carrier induced device degradation, it has been found that the maximum supply voltage is about -2.6V for 0.15$\mu$m PMOSFET.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.41 no.10
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• pp.57-62
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• 2004

We report the fiber-optic current sensors composed of a side-polished single-mode fiber with the thermo-optic Polymer layer and the metal wire as a heater. The index change of polymer layers caused by the resistant heat of the metal wires induces the optical attenuation through the evanescent field of the side-polished single-mode fiber. Two types of the sensors are proposed and their characteristics as a current sensor are investigated.