• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2007년도 춘계학술대회 논문집
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• pp.463-467
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• 2007

It is necessary to study the prevention and the management of electrical facilities because the electrical fault took place at the dust occurrence area due to environmental pollution. In particular, the dust accumulates easily on insulation material which is exposed an external long time. The leakage current brings out electrical fault after all. Also, it is need to variation of material and shape to repress a leakage current on electrical material. In this paper, we measured a leakage current on electrical material of facilities by dust, and in experiments the prevention to electrical fault was studied.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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• pp.576-577
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• 2005

In this paper, the oxidization characteristics were analyzed according to the shapes of Residual Current Protective Device(RCD) contacts. RCD is an electrical safety device specially designed to immediately switch the electricity off when electric leakage is detected at a level harmful to a person using electrical equipment. The shapes of RCD contacts are a little bit different according to the models. When RCD is turned on, stationary and moving contact do not fit together. So, it can cause the increase of contact resistance. To discover the deterioration characteristics of RCD contacts by switching repetition, the contacts were analyzed by stereo microscope, Scanning Electron Microscope(SEM) and Energy Dispersive X-ray Spectrometer(EDS).

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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• pp.234-235
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• 2006

In this study, we experimented deterioration characteristics of PVC insulation wires for electrical apparatus by series arcing and analyzed the heat generation at the contacts of wires, glowing/growing process of copper oxide, waveforms of contact voltage, current, power dissipation, and so on. We found out that how glowing contacts and surface arcing can decompose PVC insulation and that subsequent series arc can lead to ignition. We expect that these results are useful for improving fire protection technology by providing a better understanding of how electrical fires can initiate.

• 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.

• 건축역사연구
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• 제20권2호
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• pp.55-70
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• 2011

This paper aimed at analyzing of structural carpentry terminology for bracket structure in Yingzaofashi ${\ll}$營造法式${\gg}$in the era of Song Dynasty and illuminating coinage characteristics and method of Structural Carpentry Terminology for bracket Structure through graphonomy research and system and structure of these terms. The results are as follow. The structural carpentry terminologies for structure were identified to be approximately 23 words, and terminology of bracket structure鋪作 is largely categorized into 3 categories of Type鋪作次序, Structure, Place. On the other hand, the structural carpentry terminologies for parts largely categorized into 2 categories of Bracket structure鋪作, Others. Bracket structure terminologies for parts were derived from the core of Dou枓, Gong栱, Ang昂, Fang方. The phenomena of derivation in structural carpentry terminology for bracket structure can be explained by the difference in the shape of subsidiary material and the location for usage of the subsidiary material and part of the subsidiary material and their functions.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 C
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• pp.2019-2021
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• 2005

This paper describes the cut off time and the current characteristics of virgin RCDs and deteriorated ones in the seashore. The RCDs(Residual Current Protective Devices) are used for protecting the human body from electrical shock and for preventing facility accidents. According to the Korean standards, the RCDs are installed in panel boards. When RCDs are installed outside, they must be enclosed inside waterproof cases. In the case that RCOs are employed at temporary power sites and electrical facilities on the road, they are exposed to the external environment. As a result, the RCDs deteriorated in the seashore for 3 months showed high failure rate, while the virgin RCDs all complied with Korean Standard. Considering that the RCDs are used under exposed condition outside, the reliance of RCDs must be ensured by modifying the related regulations and codes and by developing Improved models advanced in their performance.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2006년도 춘계학술대회 논문집
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• pp.264-267
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• 2006

This paper describes the accident analysis by modeling the current transformer mounting in meaium voltage metal-clad switchgear(MCSG). In analyzing the accident the reconstruction at the current transformer mounting(VCB connecting guide) has to be taken into account. The accident was modelled as a 3-phase ground fault mounting between the end plate of a high voltage lines and the safety shutter at the current transformer mounting of the VCB inside the metal clad switchgear. Since the outside maintenance of the metal clad switchgear is restricted by the enclosed compartments, its circumference has to be kept clean. Through the reconstruction results, it was confirmed that the fault of the enclosed switchboard could be reduced when the shutter made of Fe material was changed into an insulation.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 춘계학술대회 논문집 센서 박막재료연구회 및 광주 전남지부
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• pp.10-14
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• 2008

In this paper, abnormal heating of circuit breaker in panel board by poor connection was studied. Firstly, calculation method of contact resistance shown in IEC 60943 was examined. Secondly, concerning abnormal heating of circuit breaker in panel board, field measurements were performed. Field measurements showed that locally abnormal heating by poor connection could be detected, therefore, in that case, immediate action was needed. Finally, experiments regarding abnormal heating between terminal of circuit breaker and electric wire were conducted. The results showed that abnormal heating above $180^{\circ}C$ was measured. Also, in the results of analysis of electrical waveforms according to load current, voltage drop occurred around poor connection, and the oxide was generated according to mechanical vibration. In order to prevent electrical disaster caused by poor connection, adequate torque should be applied to electrical connection, and periodic check-ups are needed.

• 한국세라믹학회지
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• 제16권2호
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• pp.77-82
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• 1979

Diopside-Anorthite body was easily synthesized at relatively low temperature 1225℃, compared with the synthesizing temperature 1425℃ of Anorthite. Of Diopside-Anorthite body, the synthesizing temperature was considered to be higher than 1225℃ because Gehlenite, probably formed at 1220℃, was detected by X-ray diffraction. This body has excellent physical and electrical properties, i.e. electric resistivity (1.2×1014Ωcm), low dielectric constant (6.26) and low thermal expansion coeffcient (61.9×10-7/℃). It's hardness was good enough for electrical subsidiary. In addition, this body, Diopside-Anorthite, has exellent properties for heat resisting wares.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2003년도 학술.기술논문발표회
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• pp.121-126
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• 2003

Steel frame construction is divided into subsidiary materials with column, beam, girder and bracing. After these are processed in factory for using installing in construction field. These prefabricated furniture is very important in accordance with design drawing about processing and prefabricating. In the case of design process using information transmission in blueprint, omission of material number, processing measure and finishing material, or discordance of each structure drawing and selecting incongruent structural material generated an error in the process of design. These error caused delaying tine and increasing cost and increasing safety accident in the steel-structure work operating process. therefore, design process should consider problem of operating process.