• 한국세라믹학회지
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• 제20권4호
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• pp.324-332
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• 1983

In this studies resistivity thermal expansion and microstructure of the Forsterite Porcelain as a high frequency insulator were investigated. The body containing Zn-glass shows higher resistivity than any other body. The bodies containing K, Ba, Cd-glass respectively consist of fine crystals of mosaic type. The bodies containing Bi, Zn, Zr-glass repectively included more large crystals because of the grain growth and coherence of fine particles In the 4 series Forsterite containing excess MgO 0-6% the thermal coefficients of the bodies increased with the increasing of excess MgO and the bodies have conspicuously high thermal expansion coefficients when 15% excess $BaCO_3$ was added to. The resistivities of additive bodies of $BaCO_3$ 0, 5, 10% in Forsterite containg excess MgO 2% are higher than any other that of composition. Bacause the growing of Forsterite crystals was restrained with the increasing of excess MgO $BaCO_3$ their grain size became fine and their grain boundaries were decomposed and also the glass phase having high refractive inder was increased. The higher the firing temperature increased the more the process of crystal growing was progressed.

• 한국전기전자재료학회논문지
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• 제16권9호
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• pp.842-850
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• 2003

The suspension insulators are subjected to harsh environments in service for a long time. The long-term reliability of tile insulators is required for both mechanical and electrical performances. This study describes some basic performance tests and accelerated aging test by cool-heat cycling methods and thermal mechanical performance test methods on alumina porcelain insulators (new and aged) used for transmission line in KOREA. There was no fail in electrical and mechanical performance tests such as a high voltage strength, a flashover voltage, and an impact strength in all samples. But in the case of accelerating aging tests which have above 9$0^{\circ}C$ temperature gradient, fracture phenomena was happened by a thermal shock in tile aged sample(sample A) with low alumina porcelain body. It was indicated that sample A was more severely aged than other samples. According to results of HRB test and microstructural analysis, it was reasoned that insulator bodies with the matrix reinforced with alumina crystalline phase have advantages over the suppression of crack advance. And cool-heat aging and mechanical thermal ageing tests shows that a temperature gradient is more effective to accelerating than a cycling number.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 1997년도 International Symposium on Fire Science and Technology
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• pp.120-129
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• 1997

The fire protective coating can reduce certain damages in case of fire, also conserve energy by thermal insulation and prevent corrosion and errosion in normal daily life by means of blocking thermal transfer, that were generally made of organic, inorganic and metallic materials as adiabatic coating. In case of inorganic material such as soluble silicate, it produces less toxic substances which are exposed to Ore, and have a plenty of raw material. Also inorganic thermal insulator is good in heat resistance. To develope such a excellent inorganic thermal insulator, the study of fire protective coating using the alkali silicate is necessary The principle of intumescence for alkali silicate is from rapid evolution of water in the coating material, the quantity of water in it is of course influenced on the degree of intumescence. The phenomenon of intumescence in ternary silicate is increased as the radius of ion is bigger, and this is caused by evolution of so many kinds of water. The individual degree of intumescence is ordered like this ; $K^+$ > $Na^+$ > $Li^+$ . The best protection effect is similarity found to intumescence of ternary silicate. The result of X-ray diffraction analysis indicates that $KHSi_2O_5$ is an important ingredient in K-silicate.

• Journal of Electrical Engineering and Technology
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• 제10권1호
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• pp.299-307
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• 2015

Reduction in pollution performance of polymeric insulators, aged due to water absorption stress and thermal stress, is a major threat to the reliable operation of power transmission and distribution system. Formation of partial discharges on the surface of wet polluted insulator plays a major role in determining the life time and pollution performance of outdoor polymeric insulators. However, reports on partial discharge characteristics of water absorption stress aged and thermal aged polymeric insulators are scanty. This paper discusses the pollution performance characteristics of accelerated aged polymeric insulators using the advanced ultra wide band PD signal measurement and analysis. Laboratory experiments on accelerated aged polymeric insulators were carried out as per IEC 60507 under AC voltage, at different humidity and contamination levels using NaCl as a contaminant. PRPD pattern and Time-Frequency map analysis of PD signals were carried out. From the results, it can be speculated that PD analysis is a well suited technique to understand the pollution performance of aged polymeric insulators.

• 한국결정성장학회:학술대회논문집
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• 한국결정성장학회 1998년도 PROCEEDINGS OF THE 14TH KACG TECHNICAL MEETING AND THE 5TH KOREA-JAPAN EMGS (ELECTRONIC MATERIALS GROWTH SYMPOSIUM)
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• pp.145-148
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• 1998

Fluoride({{{{ { CaF}_{2 } }}}}) films exhibited a cubic structure with similar lattice constant to that of Si and have sufficient breakdown electric field as gate dielectric material. Therefore, {{{{ { CaF}_{2 } }}}} are expected to replace conventional insulator such {{{{ { SiO}_{ 2},{Ta}_{2}{O}_{ 2} and{Al}_{2}{O}_{5}. However, {CaF}_{2}}}}} films showed hystereisis properties due to mobile charges in the film. To solve this problem we performed thermal treatment and achieves field. C-v results indicate a reduced hystereisis window of {{{{ }}}}ΔV =0.2v, LOW INTERFACE STATE {{{{{D}_{it}=2.0 TIMES {10}^{11}{cm}^{-1}{eV}^{-1}}}}} in midgap, and good WIS diode properties. We observed a preferential crystallization of(200) plane from XRD analysis. RTA treatment effects on various material properties of {{{{{CaF}_{2}}}}} are presented in this paper.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 춘계학술대회 논문집 유기절연재료 전자세라믹 방전플라즈마 연구회
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• pp.186-188
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• 2001

In this study, the correlation between leakage currents and temperature rise was investigated for the more accurate diagnosis of bad insulator by use of the infrared camera. For the purpose, leakage currents and thermal images were measured for the artificially aged insulators using salt fog. From the results, it is concluded as follows ; in case of artificially aged insulators, the leakage. current was decreased with the duration of voltage application and was largely affected by humidity, which seems due to ionic conduction. Also, the correlation between temperature rise and leakage current was appeared to be quite linear, although it showed below linearity at large leakage current.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2013년도 추계 학술논문 발표대회
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• pp.198-199
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• 2013

To prevent energy waste in buildings used heat insulator. Heat insulator materials can be classified inorganic and organic. The inorganic material has lower water resistance. The inorganic material is heavy and worse thermal performance than organic materials. Technologies on energy saving and materials used in curtain walls have progressed with increase of high-rise and large buildings. However, there is little study to explain water resistance performance of the curtain walls. This study focused on evaluation of insulation of inorganic materials and performance evaluation by thermal conductivity.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2012년도 춘계학술대회 논문집
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• pp.1053-1054
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• 2012

• 한국재료학회:학술대회논문집
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• 한국재료학회 2003년도 추계학술발표강연 및 논문개요집
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• pp.151-151
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• 2003

열화학기상증착법(Thermal-CVD)을 이용하여 SOI(snilicon-on-insulator)기판과 실리콘기판 상에 단결정 3C-SiC 이종박막을 동시에 성장하고, 그 특성을 비교 분석하였다. 결정성 평가로는 X-선 회절(XRD)분석과 Raman 산란 분광분석, 그리고 투과전자현미경을 이용하였고, 잔류 웅력 비교 분석으로는 laser scanning 방법 과 Raman 산란 분광분석의 3C-SiC LO peak의 위치변화, 그리고 X-선 회절분석의 3C-SiC(004) peak의 위치변화를 이용하였다. 그 결과 SOI 기판과 실리콘 기판상에 고품위의 단결정 3C-SiC 박막이 성장됨을 확인하였고, SOI 기판을 사용한 경우 실리콘 기판에 비해 성장된 3C-SiC 이종박막의 잔류 응력이 실제로 감소됨을 확인하였다.

• 대한기계학회논문집B
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• 제41권6호
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• pp.409-414
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• 2017

본 연구의 목적은 실제 실리콘 박막 트랜지스터 내 포논 전달 특성을 이해하는 것이다. 이를 위해 박막 소자 내 열해석 예측 정확성이 검증된 전자-포논 상호작용 모델을 이용하여 반도체 산업에서 중요한 Silicon-on-Insulator(SOI) 시스템에 대한 다양한 조건에서 전자-포논 산란에 의한 Joule 가열 메커니즘의 고려하여 포논 전달 해석을 수행했다. 소자 장치 전원(device power)과 실리콘 층 두께 변화에 따른 포논의 평균자유행로(mean free path) 스펙트럼에 대한 열적 특성을 조사하여, 실제 SOI 소자 내 포논 전달을 이해했다. 이 결과는 SOI 소자의 신뢰성 설계 및 고효율 열소산(heat dissipation) 설계전략에 필요한 포논 전달 특성 이해에 활용될 수 있다.