• 한국초전도ㆍ저온공학회논문지
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• 제5권3호
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• pp.38-42
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• 2003

HTS transformer is promising one of HTS power applications to be commercialized in the near future. To realize the applications, insulation technology in the coolant, liquid nitrogen, should be established. So breakdown characteristics should be considered at insulation components; turn-to-turn, layer-to-layer, winding-to-winding, were investigated. Firstly breakdown strengths of Kapton films were compared with Kraft paper these are as turn insulator. And next the characteristics of surface flashover on FRP were measured and the influence on breakdown strength of bubble generated with joule heat was discussed with the shape of cooling channel between layers. Finally barrier effect at winding-to-winding was discussed.

• 진공이야기
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• 제3권1호
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• pp.16-21
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• 2016

FinFETs are able to be scaled down to 22 nm and beyond while suppressing effectively short channel effect, and have superior performance compared to 2-dimensional (2-D) MOSFETs. Bulk FinFETs are built on bulk Si wafers which have less defect density and lower cost than SOI(Silicon-On-Insulator) wafers. In contrast to SOI FinFETs, bulk FinFETs have no floating body effect and better heat transfer rate to the substrate while keeping nearly the same scalability. The bulk FinFET has been developed at 14 nm technology node, and applied in mass production of AP and CPU since 2015. In the development of the bulk FinFETs at 10 nm and beyond, self-heating effects (SHE) is becoming important. Accurate control of device geometry and threshold voltage between devices is also important. The random telegraph noise (RTN) would be problematic in scaled FinFET which has narrow fin width and small fin height.

• 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.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.111-111
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• 2010

The mold transformers have been widely used in underground substations in large building and have some advantages in comparison to oil-transformer, that is low fire risk, excellent environmental compatibility, compact size and high reliability. In addition, the application of mold transformer for outdoor is possible due to development of epoxy resin. The mold transformer generally has cooling duct between low voltage coil and high voltage coil. A mold transformer made by one body molding method has been developed for small size and low loss, but it needs some cooling method because heat radiation between each winding is difficult. In this paper, the temperature distribution and thermal stress analysis of H class 100kVA pole cast resin transformer for power distribution are investigated by FEM program.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2018년도 춘계 학술논문 발표대회
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• pp.222-223
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• 2018

Recent government policies are increasing interest in zero-energy housing, a building that minimizes energy consumption (90% reduction). As the importance of building passive performance is emphasized, the role of insulation is increasing as a way to reduce indoor heat loss in order to minimize the use of cooling and heating energy. There are two main types of insulation. Organic insulation is widely used for various construction structures such as construction and industrial due to some merits such as the convenience of construction and construction cost. However, it has been pointed out as a main cause every time a fire accident occurs, Jecheon Sports Center', the fire damage of buildings caused by the use of organic insulation materials is expanding to social problems, so it is urgent to research on nonflammable inorganic insulation materials.

• 한국전기전자재료학회논문지
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• 제16권11호
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• pp.1001-1007
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• 2003

The silicone fluids have been generally used as processing agent in silicone rubber(SIR) compounding. The addition of hydroxy silicone (HS) fluids to SIR for insulator housing material is required to meet the good electrical performance and the good processability. In this study, SIR with HS fluids was evaluated to investigate how the kinds of them affect insulation properties. The contact angle of the virgin sample of 40-HS SIR was low and its recovery rate was also slow. The recovery rate of 50-HS SIR was the highest being decreased with the viscosity increase of HS fluids. The tracking resistances and the corona aging resistance of 70-HS SIR and 1,040-HS SIR were excellent Tracking resistance depended largely on heat resistance of silicone fluids. But arc resistance didn't depend merely on the kind of silicone fluids.

• 한국전기전자재료학회논문지
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• 제14권8호
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• pp.658-662
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• 2001

This paper describes on the fabrication and characteristics of hot-film type micro-flowsensors integrated with Pt-RTD(resistance thermometer device) and micro-heater on the SOI(Si-on-insulator) membrane and trench structures, in which MGO thin-film was used as medium layer in order to improve adhesion of Pt thin-film to SiO$_2$ layer. Output voltages increased due to increase of heat-loss from sensor to external. The output voltage was 250 nV at N$_2$ flow rate of 2000 sccm/min, heating power of 0.3 W. The response time($\tau$:63%) was about 42 msec when input flow was step-input. The results indicated that micro-flowsensors with the SOI membrane and trench structures have properties of a high-resolution and ow consume power.

• Journal of Magnetics
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• 제16권4호
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• pp.403-407
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• 2011

Metal-insulator type, nano-granular soft magnetic films have been reviewed from the viewpoint of high frequency magnetic materials. The formation of nano-granular structure is related to the magnitude of heat of formation of intergranule materials. Variation of the ratio of granule phase to intergranule phase in the film is found to produce various characteristics in the magnetic properties of the film. The HRTEM observation reveals that neighboring granules in the film with above 60 at.% Co, contact at considerable points and the films show soft magnetic properties which are explainable in terms of the random anisotropy model for nano-crystalline materials. Addition of Ni group elements in Co-O based films enhances their anisotropy field up to 400 Oe and they exhibit excellent frequency response of permeability. Also, large electromagnetic noise suppression effect is demonstrated as one of their potential applications.

• 반도체디스플레이기술학회지
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• 제3권4호
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• pp.29-32
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• 2004

Fully depleted Silicon-on-Insulator (FD-SOI) devices lead to better electrical characteristics than bulk CMOS devices. However, the presence of a thin top silicon layer and a buried SiO2 layer causes self-heating due to the low thermal conductivity of the buried oxide. The electrical characteristics of FDSOI devices strongly depend on the path of heat dissipation. In this paper, we present a new three-dimensional (3-D) analysis technique for the self-heating effect of the finger-type and bar-type transistors. The 3-D analysis results show that the drain current of the finger-type transistor is 14.7% smaller than that of the bar-type transistor due to the 3-D self-heating effect. We have learned that the rate of current degradation increases significantly when the width of a transistor is smaller that a critical value in a finger-type layout. The current degradation fro the 3-D structures of the finger-type and bar-type transistors is investigated and the design issues are also discussed.

• 한국결정성장학회지
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• 제9권3호
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• pp.347-352
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• 1999

세라믹 애자 건조공정의 유한요소 시뮬레이션으로 건조공정중 애자의 온도분포, 습도분포, 습열응력분포, 그리고 변형형상을 예측하였다. 유한요소 수식화에서 온도구배, 습도구배, 전도, 대류 및 증발을 고려하여 불소성 세라믹의 온도분포와 습도분포를 구하였고, 온도 및 습도변화로 인한 체적 변화로부터 습열응력을 구하였다. 유한요소 수식화를 기초로 컴퓨터 프로그램을 개발하고, 개발된 프로그램을 사용하여 세라믹 애자의 건조공정을 시뮬레이션 하였다.