• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.21-24
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• 2000

lnSb temperature dependent hall effect of multilayerd structures were investigated. According to variation of magnetic field measured hall coefficient, Hall mobility, carrier density and hall voltage. For the measurement of electrical properties of hall device, evaperated InSb thin film fabricated with series and parallel multilayers. We found that the XRD analysis of InSb thin film showed good properties at 20$0^{\circ}C$, 60 minutes. Resistance of ohmic contact increased linearly due to increasing current. Some of device fabrication technique and analysis of Hall effect were discussed.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.4
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• pp.885-891
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• 2011

In this paper, we studied dc leakage current properties analysis of LED lamps of road and landscape lighting when leakage current appeared in dc power line. Generally, converter of LED lighting is divides to insulated type and non-insulated type according to components. When electric leakage happened in AC power line, earth leakage breaker(ELB) senses leakage current and interrupts electric circuit. In dc power source, We need experimental verification about dc electric leakage for electricity safety. In normal wiring conditions and in the water, in case of using insulated type of converter, dc leakage current did not occur. However, in case of using non-insulated type of converter, dc leakage current occurred and passed through into the ground. We found that there is a hazard of electric shock by dc leakage current. We expect that the results of these studies would be helpful for electrical safety of LED lamps for road and landscape lighting.

• Proceedings of the KIEE Conference
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• 1998.11c
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• pp.901-903
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• 1998

Crosslinked Degree is an important factor to determine dielectric property of crosslinked polyethylene(XLPE) used for the insulation material in power cables. Recently, though it is necessary to investigate electrical properties according to crosslinked degree as a part of the whole characterization of cable. it is not examined closely. In this study, crosslinked degree of samples were measured according to temperature and holding time of crosslinking, electrical tree characteristics of these samples were analyzed by crosslinked degree and applied temperature that was changed from normal temperature to operating temperature of power cables. As a result. when the crosslinked degree was low, dielectric properties were decreased and influence of temperature was increased. but the crosslinked degrees were high. initiation voltages of treeing were increased and dielectric properties were improved. It is proved that the optimum. crosslinked degree was one of most important factor for aging time and residual lifetime of power cable.

• Transactions on Electrical and Electronic Materials
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• v.14 no.1
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• pp.39-42
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• 2013

The effects of particle size on the mechanical and electrical properties of epoxy/spherical silica composites were studied. The silica particle sizes were varied from 5 to 30 ${\mu}m$ and the filler content was fixed to 60 wt%. Tensile and flexural tests were carried out and the interfacial morphology was observed by scanning electron microscopy (SEM). The electrical insulation breakdown strength was estimated using sphere-sphere electrodes with different insulation thicknesses of 1, 2 and 3 mm. The tensile strength and flexural strength increased with decreasing particle size, while electrical insulation breakdown strength increased with increasing particle size.

• Journal of the Korean Society of Safety
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• v.22 no.4
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• pp.26-31
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• 2007

According to the statistical analysis on the electrical fire of 2005 years, most of electrical fire is generated from short circuit(4,985 cases), overcurrent(755 cases) leakage current(391 cases), poor contact(378 cases), disconnection(36 cases) on the electrical wiring device. The researches for the fire hazard about normal electric wiring have already been progressing in the advanced country such as USA and Japan, but Comparative study of the disconnection has not been conducted. Therefore, in this paper, we have simulated the thermal analysis for electrical wire according to deteriorating time in a normal state and disconnection with electrical wire using the electrical-thermal finite element method(Flux 3D). This paper acquire basis data of electricity fire signal by disconnection and wish to help for electrical fire cause diagnosis business.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2009.10a
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• pp.335-338
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• 2009

In this study, in order to investigate the thermal and electrical properties of ZnO arrester block against 60[Hz] AC voltage, the changes in leakage current were measured. The temperature distribution appearing on the ZnO arrester blocks was observed using a forward looking infrared camera. In particular, the correlation between the thermal and electrical properties of a ZnO arrester block was analyzed experimentally. From this analysis, the thermal phenomena resulting from the heat generation and dissipation of the ZnO arrester block were interpreted. The degradation and thermal runaway phenomena of ZnO arrester block are closely related to the temperature limit of the ZnO arrester block. The installation of an additional metal electrode has resulted in the decrease of the leakage current due to the heat dissipation.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1995.11a
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• pp.289-292
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• 1995

In this experiment the specimen is selected for epoxy resin used in the molding compound materials for the power semiconductors. The specimen was divided into the two parts. one is a specimen without irradiation, the other is irradiated with electron beam, of which dose is 1[Mrad], 2[Mrad], 4[Mrad], 8[Mrad] and 24[Mrad], respectively. From the analysis for the physical properties of the specimen, the carbonyl group which is asffact the electrical properties is decreased according to increase the dose of the electron beam. In the measurement of dielectric characteristics among the electrical properties, the frequency dependance of the dielectric characteristics is confirmed that its ${\beta}$-peak is represented by one peak due to attribute to the main chain below 50[$^{\circ}C$], and two peak above the temperature 100[$^{\circ}C$].

• Journal of Korea Foundry Society
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• v.31 no.6
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• pp.366-370
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• 2011

The influence of aging treatment on the microstructure, mechanical and electrical properties of Cu-Be alloy for connector material applications was investigated. The properties of mechanical strength and electrical conductivity were found to increase with increasing aging temperature. By the way, SEM/EDS and TEM analysis exhibited that beryllides precipitation (CoBe and NiBe) with a size of 50 nm were distributed in grains. It was, therefore concluded that these beryllide precipitates improved the mechanical strength and also it was favor in increasing of electrical conductivity.

• Carbon letters
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• v.16 no.1
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• pp.34-40
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• 2015

In this study, in order to improve the thermal and electrical properties of epoxy/graphene nanoplatelets (GNPs), surface modifications of GNPs are conducted using silane coupling agents. Three silane coupling agents, i.e. 2-(3,4-epoxycyclohexyl)-ethyltrimethoxysilane (ETMOS), 3-glycidoxypropyltriethoxysilane (GPTS), and 3-glycidoxypropyltrimethoxysilane (GPTMS), were used. Among theses, GPTMS exhibits the best modification performance for fabricating GNP-incorporated epoxy composites. The effect of the silanization is evaluated using transmission electron microscopy (TEM), scanning electron microscopy, thermogravimetric analysis, and energy dispersive X-ray spectroscopy. The electrical and thermal conductivities are characterized. The epoxy/silanized GNPs exhibits higher thermal and electrical properties than the epoxy/raw GNPs due to the improved dispersion state of the GNPs in the epoxy matrix. The TEM microphotographs and Turbiscan data demonstrate that the silane molecules grafted onto the GNP surface improve the GNP dispersion in the epoxy.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.54 no.3
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• pp.97-102
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• 2005

This research was a fundamental study for the low temperature sintering of PZTN by glass phase transient processing. To lower the sintering temperature, the glass phase Processing was used. Also to improve the electrical properties, the transient processing was utilized. After characterization, the various analytic techniques, such as Archimedes method for the measuring densification, x-ray diffraction patterns for the quantitative analysis of crystalline phases were utilized. Also the dielectric constant, dissipation factor, and piezoelectric coefficients were measured to evaluate the PZTN sintered at the $950^{\circ}C$ and $1050^{\circ}C$. This was confirmed that the sintering temperature of PZTN was reduced by $950^{\circ}C$ and the electrical properties were improved by the transition processing. Therefore, the glass phase transient processing can be applicable to low the sintering temperature with the dielectric and piezoelectric properties.