• 전기학회논문지
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• 제61권6호
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• pp.821-826
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• 2012

The streaming electrification process of vegetable insulating oils occurring when the oils contacted with solid material in a high power transformer circulation system seems to cause electrical discharge incidents and may cause failures. We therefore measured the dielectric breakdown voltage tendency of vegetable insulating oils flowing on the surface of the charging device with various velocity and temperature. First, the relation between the velocity and breakdown voltage tendency of vegetable oils, can be explained by volume effect and v-t effect. Second, experimental results show that applied voltage have little effect on dielectric breakdown voltage, when vegetable insulating oils used for large power transformer.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.1385_1386
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• 2009

In this paper, we examined the faulted cable joint through the external form analysis, material analysis, experimental verification and it's cause diagnosis system. It was not observed the voild, sharp material from the external form analysis and material variation. From the experimental verification, the thickness decrease of an insulator decreased ac breakdown strength suddenly and the breakdown traces of the insulator that was damaged by knife displayed elliptic shape. Thus, the faulted cable is assumed to accident that become dielectric breakdown by the deterioration of insulation performance that can happen when work.

• 조명전기설비학회논문지
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• 제29권6호
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• pp.35-41
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• 2015

This paper presents a breakdown voltage and a process of breakdown progress in mineral oil under an quasi-uniform field with decomposition products which occur after the oil discharge. The breakdown voltage in the oil revealed the characteristics of dispersion regardless of an electrode gap. The cumulative probability distribution was used to analyze the dispersion of the breakdown voltage. In addition, the process of breakdown progress in the oil can be reasonably described by the electron breakdown theory based on both electrons emitted from the cathode and ions by field-aided dissociation of the oil. The proposed breakdown process will be used for the basic data to explain the behavior pattern of the decomposition product to cause the dispersion of the breakdown voltage.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.1175-1176
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• 2007

Recently, the electronic components are used plentifully to the railway trains. This paper explains the aging mechanism which is investigated from Japanese electric trains. Investigating results about the vehicle breakdown of the machinery are explained. We can know breakdown tendency of a cause place, occurrence date etc. by investigating results.

• 대한기계학회논문집B
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• 제24권9호
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• pp.1157-1165
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• 2000

A classic examples of the abnormal combustions are the knock and misfire, which raise noxious performance and life of the engine. A heavy knock can also cause severe damages to the engine itself, which gives more reason why it must be detected and corrected. With the response of the today's requirements, we have researched the new diagnostic system which uses the breakdown voltage characteristics between electrodes of spark plug. This breakdown voltage depends on the pressure, temperature and even the shape and material of electrodes. But there is no data of breakdown voltage in case of using the spark plug as a electrodes. So, in this study, we show the breakdown voltage characteristic by pressure and temperature in constant volume bomb, which will make it possible to diagnose the engine combustion phenomenon.

• 한국화재소방학회논문지
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• 제33권1호
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• pp.15-22
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• 2019

최근 상가에서 사용되는 온장고에서 저장된 기호음료들의 유출로 인한 절연파괴로 화재가 발생한 사례가 자주 보고되고 있다. 하지만 기호음료의 전기적 특성과 음료 유출로 인한 화재 발생 원인에 대한 연구는 미비한 상태이다. 이에 본 연구에서는 이에 대한 인과 관계를 밝히고자 기호음료 32종을 선별하여 전도도 및 총 용존 고형물질(TDS)의 농도를 측정하였다. 그리고 이를 바탕으로 음료를 선별하여 전극 간 절연파괴 시험과 회로에 소자와 음료를 같이 배치한 후 모의실험을 실시하였다. 그 결과 화재 발생 가능성은 전도도가 높은 음료는 물론 낮은 음료라도 발화 가능성이 있다는 사실을 실험적으로 확인하였다. 또한, 기호 음료의 유출로 회로상에서 불꽃 방전을 일으키는 여러 조건을 발견할 수 있었다.

• 국제학술발표논문집
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• The 6th International Conference on Construction Engineering and Project Management
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• pp.691-692
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• 2015

Several scholars in South Korea have predicted that maintenance costs of social infrastructure will sharply increase from the mid-2020s, and cause budgetary deficits among facilities management agencies. Interest in infrastructure asset management (IAM) is rising as a solution to such problem. In this study, an information system for asset valuation that reflects the salvage value and deferred cost of social infrastructure based on WBS (work breakdown structure) was developed in consideration of IAM. To reuse the construction cost information such as the acquisition cost, the interconnection between CBS (cost breakdown structure) and WBS was considered. Furthermore, asset valuation information was developed with XML schema to facilitate the exchange and reuse of the information among project participants.

• 조명전기설비학회논문지
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• 제12권2호
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• pp.85-90
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• 1998

본 논문에서는 AC 전압 하에서 자유 도전성 금속이물 혼입에 의한 SF6 가스로 압축된 GIS의 절연특성에 관하여 연구하였다. GIS 내에서 자유 도전성 금속이물이 혼입되면 절연파괴 전압을 낮추는 결정적인 역할을 할 수 있으므로, 금속이물의 재질과 크기에 따른 부상전계 및 절연파괴전압을 측정하였다. 구리, 철, 알루미늄의 선형 금속이물에서의 부상전계 계산값과 측정값을 비교, 분석하였다. 압축된 $SF_6$ 가스로 절연된 동축원통전극간에 금속이물의 혼입될 경우의 절연파괴전압은 금속이물의 없을 때보다 낮게 나타났으며, 금속이물의 재질과 크기에 상당히 의존하였다. 따라서 자유도전성 금속이물은 GIS의 절연파괴 특성에 매우 중요한 요소로 작용함을 알 수 있었다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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• pp.191-192
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• 2005

The reverse breakdown voltages of 4H-SiC SBD(schottky barrier diode)s with FP(Field Plate) and/or FLR(Field Limiting Ring) as a edge termination, were investigated. The breakdown voltages of SBDs with FP ware investigated varying the overlap width from $1{\mu}m$ to $30{\mu}m$. The maximum average breakdown voltages was 475V. There is no significant changes for the devices with overlap width of between $5{\mu}m\sim30{\mu}m$. It was confirmed that the dielectric breakdown of the thin thermal oxide is main cause of device failure. However, the breakdown voltage of SBD with FLR was 1400V even though the FLR edge termination structure was not optimized.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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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.