• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.475-476
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• 2008

This paper is an experimental test for the close examination of breakdown causes of glass insulators using at the electric rail-road. The glass insulator is estimated the mechanical performance according to hitting test(ST-100, Sharp-Eng, KOR) that is based on KSC 3810. Insulators is damaged by pendulum weight at the steps of hitting angles. Glass and porcelain insulators are broken at the hitting angle of $72^{\circ}$. From the these results, glass insulator absorbed the impact from the pendulum weight but on the porcelain insulator, it is not transmitted vibration by impact. Hereafter, these results are expected that is used the data for the assessment on breakdown cause of a glass insulator.

• Proceedings of the KIEE Conference
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• 2008.05a
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• pp.191-192
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• 2008

In this paper, we investigated on the characteristics and assessment of the insulators damaged by hitting tester(ST-100, Sharp-Eng, KOR). It made that an apparatus act on KS C 3801 for the damaged characteristics and assessment of insulators according to external scattering objects. There are selected 255mm glass insulators and 254mm porcelain insulators as the specimen. The hitting angles of the damaged insulator by pendulum weight are at $72^{\circ}$. At these points, velocity of pendulum weight is about 3.04m/sec and the force is 58.16N. At the hitting angle of 26 degrees, glass insulator is diffused the vibration within it but porcelain insulator is not. The inside vibrations of glass insulator and porcelain insulator are as like as two at the hitting angle of 53 degrees. The damaged glass insulator at the hitting angle of 72 degrees hardly is not diffused.

• Proceedings of the KIEE Conference
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• 2008.05a
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• pp.189-190
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• 2008

This study was investigated a possibility of fault of glass insulator due to vibration on high-speed railway. The proper vibration of 1-glass insulator have many frequency band and high amplitude showed in high frequency than low frequency. The proper vibration of strut tube insulator was lowest 170Hz, highest 1.5kHz. The field signal amplitude of viaduct and open route were biggest moment pantograph of high-speed rail. The surface vibration(V3) amplitude of strut tube insulator was biggest. From the FFT analysis of viaduct and open route, the strut tube insulator effect by vertical vibration was big, the frequency was 82.5Hz and 105Hz, respectively. However, in comparison with the proper vibration of strut tube insulator, the resonance was not observed. Although the amplitude of insulator is high, the possibility of fault is low because the glass insulator deterioration by the accumulation of vibration do not happen.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.2044-2045
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• 2008

This paper was studied fault possibility of glass insulator through the proper vibration and field vibration comparison. The proper vibration of 1 cell glass insulator have many frequency band and high amplitude showed in high frequency than low frequency. The field signal amplitude of viaduct and open route were biggest moment pantograph of high-speed rail. From the FFT analysis of viaduct and open route, in the case of positive direction, the strut tube insulator effect by vertical vibration was big, the frequency was 82.5Hz and 105Hz, respectively. However, in the case of negative direction, the vibration did not cause big effect. In comparison with the proper vibration of glass insulator, the resonance was not observed.

• Proceedings of the KIEE Conference
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• 2008.09a
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• pp.261-262
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• 2008

Damaged glass insulator that is utilized the high-speed railroad in domestic try to find the cause. This paper is investigated on the characteristics of alumina cement as the binder of class insulator. The components of glass insulator ore stub(tin), rod(tin), shed(tempered glass), and alumina cement. If composition of alumina cement is not unified, crack of alumina cement generated. As these results, cracked marks of cement is appeared and composition of alumina cement is not unified. Therefore, it is estimated that main element of long-term degradation is a alumina cement.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.263-263
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• 2008

This paper describes the electrical strength of a toughened glass stem insulators employed for electric railways. The broken glass stem insulators for comparison were taken at site. According to the international standards, electrical strength tests with 60[Hz] voltage and with impulse voltage were carried out to them under dry and wet condition and the results were corrected by considering the temperature and humidity factors. Based on the experimental results, the electrical strength of broken glass stem insulators was compared with those of sound ones and surface flashover characteristics were also discussed. As a result, it was confirmed that the electrical discharge is formed by bridging each end of the insulator shell. The experimental results are expected to be utilized as data for electrically identifying the failure causes of glass insulators.

• Proceedings of the KIEE Conference
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• 1995.07c
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• pp.1072-1074
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• 1995

Zinc-Borosilicate is used as a side insulastor wall to make high breakdown voltage with one Field Limiting Ring in a p-n junction. It is known that surface charge can be yield at the interface of Zinc-Borosilicate Glass/Silicon system. When the glass is used as a side insulator wall, surface charge varied potential distribution and breakdown voltage improved more than 660V without using more FLR.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2005.05a
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• pp.293-298
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• 2005

Insulator is being used for material of railroad vehicles as a barrier of heat and noise. But it shows various fire properties in case of fire. In this study, we compared smoke density(Ds) values of rubber foams with the different thickness of glass fiber cross-Al foil according to the standard of ASTM E 662. The result showed that the insulator and barrier property played an important role in decreasing the value of smoke density

• The Transactions of the Korean Institute of Electrical Engineers
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• v.45 no.3
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• pp.386-392
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• 1996

Zinc-Borosilicate is used as a side insulator wall to make high breakdown voltage with one Field Limiting Ring in a power p-n junction device in simulation. It is known that surface charge density can be yield at the interface of Zinc-Borosilicate glass / silicon system. When the glass is used as a side insulator wall, surface charge varied potential distribution and breakdown voltage is improved 1090 V under the same structure.The breakdown voltage under varying the surface charge density has a limit value. When the epitaxial thickness is varied, the position of FLR doesn't influence to the breakdown characteristic not only under non punch-through structure but also under punch-through structure. (author). 7 refs., 12 figs., 2 tabs.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.874-877
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• 2001

SOI(Silicon-On-Insulator) technology is proposed as an alternative to bulk silicon for MEMS(Micro Electro Mechanical System) manufacturing. In this paper, we fabricated the SOI wafer with uniform active layer thickness by silicon direct bonding and mechanical polishing processes. Specially-designed electrostatic bonding system is introduced which is available for vacuum packaging and silicon-glass wafer bonding for SOG(Silicon On Glass) wafer. We demonstrated thermopile sensor and RF resonator using the SOI wafer, which has the merits of simple process and uniform membrane fabrication.