• Proceedings of the KIEE Conference
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• 1999.11d
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• pp.1099-1101
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• 1999

PJB(Prefabricated Joint Box) is consisted of three major components ; an epoxy unit, a stress relief cone and a spring unit. The insulation structure of PJB is maintained by the interfacial pressure, and the dielectric performance at the interface depends on the interfacial pressure which is regarded as the most important factor for preventing breakdown failure. This experiment was performed to investigate breakdown voltage characteristic and partial discharge patterns under the controlled pressure conditions at the simulated interface. Finally, this paper presents the optimal pressure conditions at the interface by analyasing the PD patterns.

• Proceedings of the KIEE Conference
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• 2004.11a
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• pp.46-48
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• 2004

A micro-scale discharge device has been fabricated using MEMS technology and failure mechanisms during DC discharge are investigated for the microstructure. The failure of sustaining the plasma is mainly caused by either open or short of the micro-electrodes, both resulting from the sputtered metal atoms during the DC discharge. The glow discharge lifetime of the microstructures is found to depend on bias circuit scheme as well as the electrode structure. Based on the understanding of the failure mechanism, a novel microstructure is suggested to improve discharge lifetime and the longer lifetime is experimentally demonstrated. In addition to the failure mechanism, an electric breakdown between two electrodes with microns gap are studied using micromachined metal structures. The electrode gap is able to be accurately controlled by thickness of a sacrificial layer and the electric breakdown was measured while varying the gap from $2{\mu}m$ to $20{\mu}m$. The electric breakdown behavior was found to highly depend on the electrode material, which was not considered in Paschen's law.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.9
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• pp.1181-1188
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• 2018

In order to develop new insulating materials for GIS Spacer using environmentally friendly insulating gas, three kinds of dispersed liquid nano composites of solid epoxy /nano layered silicate filled material were prepared. And the epoxy/nano/micro silica composite was prepared by mixing epoxy/nano 3 phr dispersion/4 kinds of filler contents(40,50,60, 70wt%). The electrical insulation breakdown strengths of the nano and nano/micro mixed composites were evaluated by using 8 kinds of samples including the original epoxy. The mechanical tensile strength of the epoxy / nano / micro silica composite were evaluated, also. The TEM was measured to evaluate the internal structure of nano/micro composites. As a result, it was confirmed that the layered silicate nano particles was exfoliated through the process of inserting epoxy resin between silicate layers and the layers. In addition, dispersion of nano / micro silica resulted in improvement of electrical insulation breakdown strength with increase of filling amount of dense tissue with nanoparticles inserted between microparticles. In addition, the tensile strength showed a similar tendency, and as the content of microsilica filler increased, the mechanical improvement was further increased.

• Proceedings of the KIEE Conference
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• 1993.07b
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• pp.572-574
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• 1993

In order to obtain superior breakdown properties of Epoxy/$SiO_2$ composite materials at room and high temperature, the simultaneous interpenetrating polymer networks(SIN) is introduced into the Epoxy resin. As a result, it is observed that dielectric breakdown strength tends to increase according to the following order ; Epoxy/$SiO_2$ specimens, specimens treated with coupling agent and SIN introduced specimens which have stable temperature characteristics at room and high temperature. For introducing SIN Epoxy/$SiO_2$ composite material, rise of glass transition temperature and suppression of defects in its internal structure is achieved. This in turn improves the dielectric breakdown strength and the heat proof property of Epoxy/$SiO_2$ composite materials.

• Proceedings of the Korea Society of Information Technology Applications Conference
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• 2007.11a
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• pp.137-137
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• 2007

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2011.06a
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• pp.713-714
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• 2011

• Journal of The Institute of Information and Telecommunication Facilities Engineering
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• v.2 no.4
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• pp.52-63
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• 2003

This study proposes a change from the currentexpected price integrated system, which is based on the standard of estimated unit manpower and material, to a new actual construction cost integrated system. In order to implement it, the standard method of measurement organization system as well as the communication area standard of estimated unit manpower and material should be changed Moreover, the work breakdown structure and itemized structure should be assorted.

• Journal of the Korean Institute of Telematics and Electronics
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• v.24 no.3
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• pp.478-485
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• 1987

Optimization of the sub-micron N-channel MOSFET with the LDD(Lightly Doped Drain)structure has been investigated. LDD devices with various length of n-region, n-dose and n-implantation species were fabricated for this purpose. It will be shown that LDD devices have lower substrate current by an order of magnitude and higher breakdown voltage than the conventional devices with comparable channel length. Optimized LDD structure has been found when the sidewall thickness is 2500\ulcorner and n-region is phosphorus implantd with the dose of 1.0E13/cm\ulcorner It has been found that transconductance degradation is less than 20%.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1997.11a
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• pp.25-29
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• 1997

Capacitor-type MONOS (metal-oxide-nitride-oxide- semiconductor) NVSMs with 23$\AA$ tunneling oxide and 40$\AA$ blocking oxide were fabricated. The thicknesses of nitride layer were 45$\AA$, 91$\AA$ and 223$\AA$, Breakdown characteristics of MONOS devices were measured to investigate the reliability of superthin ONO structure using ramp voltage and constant voltage method. Reducing the nitride thickness will significantly increase the reliablity of MONOS NVSM.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2006.05a
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• pp.268-271
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• 2006

We have studied the backward wave oscillator, a power-pulsed generator oscillator at 20 GHz has higher frequency then current one. An absolute instability linear analysis was used for the purpose of designing the slow wave structure. A large diameter of the slow wave structure was adopted to prevent the breakdown brought about by the increase of power density.