• 한국화재소방학회논문지
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• 제24권5호
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• pp.136-141
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• 2010

본 연구에서는 옥내 조명 설비의 전원을 ON/OFF 하기 위해 사용되는 저압용 스위치의 구조 및 발열 메커니즘을 제시하고, 에너지원의 종류에 따라 스위치의 고정금구 및 가동 접점 등의 소손패턴을 제시함으로써 향후 예상되는 PL 분쟁의 판단 근거를 확보하는데 있다. 스위치에 인가된 일반 화염은 한국산업규격(KS)의 난연성 시험 방법을 적용하였다. 또한 스위치에 공급된 전류는 대전류공급장치(PCITS)를 이용하였다. 실험이 진행될 때 주위의 온도는 $22{\pm}2^{\circ}C$, 습도는 40~60%를 유지시켰다. 스위치의 발열은 배선과 클립의 접속 불량, 가동 접점의 절연 열화 및 접촉 불량 등에 의해서 생성되는 것으로 판단된다. 일반 화염에 의해 소손된 스위치는 표면이 균일하게 탄화되었으며, 화원을 제거하면 자연 소화되었다. 일반화염에 의해 탄화된 스위치를 분해한 결과 고정금구 및 가동 접점 등은 비교적 양호한 형태를 보였으나 외함, 클립 지지대, 가동 접점, 표시램프 등에서 탄화 및 변색을 확인할 수 있었다. 과전류에 의해 소손된 스위치는 배선을 연결하는 클립 및 클립 지지대 등은 소손의 흔적이 거의 없으나 고정금구, 가동 접점, 표시 램프 등은 심하게 탄화되었다. 즉 접촉 저항이 큰 부분에서 집중적으로 소손되었고 내부에서 외부로 탄화가 진행되는 패턴을 나타냈다. 따라서 소손된 스위치의 탄화 패턴 및 금속 금구류의 특성을 분석하면 최초의 에너지원 판정이 가능하다.

• 전기학회논문지P
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• 제59권4호
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• pp.462-466
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• 2010

The purpose of this study is to evaluate the safety of a wire connector fabricated for the effective installation of a lighting fixture including its contact resistance, insulation resistance, withstanding voltage characteristics, etc., and to provide the basis for the analysis and judgment of PL(Product Liability) dispute by presenting a damage pattern due to a general flame and overcurrent. This study applied the Korean Standard (KS) for the incombustibility test of the connector using a general flame and performed an overcurrent characteristics test of the connector using PCITS (Primary Current Injection Test System). The contact resistance of the housing connector was measured using a high resistance meter and the insulation resistance was measured using a multimeter. In addition, a supply voltage of AC 1,500V for testing the withstanding voltage characteristics was applied to both ends of the connector. Measurement was performed on 5 specimens and the measured values were used as a basis for judgment. Since the connector is fabricated in the form of a housing, it can be connected and separated easily and has a structure that allows no foreign material to enter. In addition, since it has a structure that allows wires to be connected only when their polarity is identical, any misconnection that may occur during installation can be prevented. When the incombustibility test was performed by applying a general flame to the connector, it showed outstanding incombustibility characteristics and the blade and blade holder connected to the housing remained firmly secured even after the insulation sheath (PVC) was completely destroyed by fire. In addition, the mechanism of the damaged connecting wire showed a comparatively uniform carbonization pattern and it was found that some residual melted insulation material was attached to both ends. In the accelerated life test (ALT) to which approximately 500% of the rated current was applied, the connector damage proceeded in the order of white smoke generation, wire separation, spark occurrence and carbonization. That is, it could be seen that the connector damaged by overcurrent lost its own metallic color with traces of discoloration and carbonization. The contact resistance of the connector at a normal state was 2.164mV/A on average. The contact resistance measured after the high temperature test was 3.258mV/A. In addition, the insulation resistance after the temperature test was completed was greater than $10G\Omega$ and the withstanding voltage test result showed that no insulation breakdown occurred to all specimens showing stable withstanding voltage and insulation resistance characteristics.

• 디지털융복합연구
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• 제15권12호
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• pp.265-272
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• 2017

스마트폰의 위치기반서비스가 활발히 사용됨에 따라 사용자들이 자신의 위치정보의 노출에 대한 염려가 커지고 있다. 본 연구는 프라이버시 계산 이론에 기반하여 스마트폰 사용자들이 자신의 위치정보의 제공을 어떻게 받아들이는지 확인하고자 연구모형을 개발하였다. 대학생을 대상으로 수집한 데이터를 SmartPLS를 이용하여 분석한 결과 프라이버시 계산 관점의 기존 연구와는 다른 결과를 얻었다. 프라이버시 계산이론은 인간은 합리적인 존재이며, 위험과 효과 측면을 고려하여 프라이버시 정보의 제공을 결정한다고 본다. 본 연구의 결과는 프라이버시 염려는 위험에 유의하게 영향을 미치나, 사용의도는 효과에 의해서 유의하게 영향을 미쳤다. 이러한 결과는 감정적 판단과 행동적 판단이 서로 상이한 요인에 의해서 영향을 받는다는 행동경제학적 관점과 일치한다.

• 전기학회논문지
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• 제60권6호
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• pp.1274-1279
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• 2011

The purpose of this paper is to present the manufacturing defect and damage pattern of a 3 phase 22.9/3.3kV oil immersed transformer, as well as to present an objective basis for the prevention of a similar accident and to secure data for the settlement of PL related disputes. It was found that in order to prevent the occurrence of accidents to transformers, insulating oil analysis, thermal image measurement, and corona discharge diagnosis, etc., were performed by establishing relevant regulation. The result of analysis performed on the external appearance of a transformer to which an accident occurred, the internal insulation resistance and protection system, etc., showed that most of the analysis items were judged to be acceptable. However, it was found that the insulation characteristics between the primary winding and the enclosure, those between the ground and the secondary winding, and those between the primary and secondary windings were inappropriate due to an insulating oil leak caused by damage to the pressure relief valve. From the analysis of the acidity values measured over the past 5 years, it is thought that an increase in carbon dioxide (CO2) caused an increase in the temperature inside the transformer and the increase in the ethylene gas increased the possibility of ignition. Even though 17 years have passed since the transformer was installed, it was found that the system's design, manufacture, maintenance and management have been performed well and the insulating paper was in good condition, and that there was no trace of public access or vandalism. However, in the case of transformers to which accidents have occurred, a melted area between the upper and the intermediate bobbins of the W-phase secondary winding as well as between its intermediate and lower bobbins. It can be seen that a V-pattern was formed at the carbonized area of the transformer and that the depth of the carbonization is deeper at the upper side than the lower side. In addition, it was found that physical bending and deformation occurred inside the secondary winding due to non-uniform pressure while performing transformer winding work. Therefore, since it is obvious that the accident occurred due to a manufacturing defect (winding work defect), it is thought that the manufacturer of the transformer is responsible for the accident and that it is lawful for the manufacture to investigate and prove the concrete cause of the accident according to the Product Liability Law (PLL).