• 전기전자학회논문지
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• 제11권4호
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• pp.152-157
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• 2007

본 연구에서는 AlGaN/GaN HEMT (High electron mobility transistor)를 제작하고 20 mTorr의 챔버 압력과 15 sccm의 ${N_2}O$ 유량, 40 W의 RF 전력의 조건으로 원거리에서 형성된 플라즈마로 소스와 드레인 영역을 10초${\sim}$120초 동안 처리하여 HEMT의 전기적 특성을 관찰하였다. 상온에서 ${N_2}O$ 플라즈마에 처리한 경우 HEMT의 특성이 변화하지 않았으나 $200^{\circ}C$의 온도에서 10초 동안 처리한 경우 게이트 길이가 1um, 소스와 드레인 사이의 거리가 4um인 HEMT의 게이트 누설전류가 246 nA로부터 1.2 pA로 크게 감소하였다. 또한 25 um 떨어진 200um 폭의 두 활성층 사이 누설전류가 3 uA로부터 7 nA로 감소하였으며 720 ${\Omega}/{\box}$의 활성층의 면저항을 608 ${\Omega}/{\box}$로 감소시켜 도전율의 증가를 나타내기도 하였다. ${N_2}O$ 플라즈마의 처리에 의한 전기적 특성 개선은 10초 이내의 짧은 시간 동안 이루어지며 더 이상의 처리는 누설전류 특성 개선에 도움이 되지 않았다. 또한 ${N_2}O$ 플라즈마 처리로 개선된 특성은 $SiO_2$의 증착과 식각 후에도 개선된 특성이 유지되었다. ${N_2}O$ 플라즈마의 처리는 트랜지스터의 트랜스컨덕턴스와 드레인 전류의 증가, 드레인 전류의 차단특성의 개선에도 기여하여 고품위의 AlGaN/GaN HEMT 제작에 효과적으로 이용될 수 있음이 확인되었다.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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• pp.118.2-119
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• 2003

This study was undertaken to assess overall effects of bisphenol A, a monomer widely used in manufacturing polycarbonate plastics or epoxy resin, exposure on immune system of mice. For in vitro evaluation, serial concentration of SPA was added into culture of various immune cells from normal female ICR mice, and for in vivo or ex vivo assessment, mice were orally exposed to BPA dissolved in olive oil as doses of 500, 1000, 2000 mg/g b.w. for acute expose or 100, 500, 1000 mg/kg/day b.w. 5days a week for subacute exposure. (omitted)

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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• pp.314-316
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• 2008

We examine the surface alignment of liquid crystals (LC's) by a double linearly polarized ultraviolet (LPUV) light expose process. Exposing polarized light induces a surface anisotropy to polyimide (PI) layer surfaces and hence determines the alignment direction. LPUV exposes with angular difference of $45^{\circ}$ between two polarization directions make LC director change.

• Journal of Electrical Engineering and information Science
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• 제3권1호
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• pp.68-72
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• 1998

The photomachinable glass-ceramics of Ag and CeO2 doped Li203-SiO2 (LAS)glass system was investigated as a function of UV irradiation time. After the expose and the non-exposed samples were heated, they went under crystalline phase with DTA, SEM, TEM and XRD of normal/high temperature. In this work, crystalline phases, microstructure and dielectric properties were studied under the various time of UV irradiation and heat treatment.

• Imaging Science in Dentistry
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• 제37권3호
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• pp.117-126
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• 2007

Although the diagnostic information provided by radiographs may be of definite benefit to the patients, the radiographic examination does carry the potential for harm from exposure to ionizing radiation. Therefore we should try to expose radiation as low as reasonably achievable and to give diagnostic information to patients as much as possible. All of dentists should have competence in radiation protection. I wish to deal with what we should do for the optimization of radiation protection in dental clinic.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 2002년도 춘계공동학술대회
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• pp.974-978
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• 2002

For the efficient operation of container terminals, it is essential to develop optimal operation rules for marshaling yard and yard cranes. However, derision rules for conventional container terminals expose various limitations to be applied to automated container terminals. This paper introduces a development of a simulation model for evaluating various operation rules for automated transfer cranes (ATCs) and yard operation in the marshaling yard.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2002년도 춘계학술대회 논문집
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• pp.417-422
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• 2002

This paper describes the result of wearing test on the Sangju test track. The purpose of the test is to evaluate an amount of wearing for EMU's panto shoes. Panto shoes are affected in wearing by environment of owing to expose the vehicle. Especially, the rainy season, they are found easy to get an increase in wearing of panto shoes. To evaluate an amount of wearing, we ca]lied out running test for 5 months under the ground line conditions.

• 한국방재학회:학술대회논문집
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• 한국방재학회 2008년도 정기총회 및 학술발표대회
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• pp.497-500
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• 2008

The typhoon is provoking huge damage attacking in Korea periodically every year. Therefore, in this study, the analysis of 24 hourly maximum precipitation change related to typhoon events achieved based on Mann-Whitney U test, T test, Modified T test, Sign test, F test, and Modified F test. At the results, the 24 hourly maximum precipitation was expose that average and standard deviation are increasing recently. Therefore, hydorlogical structures have to be prepared of extreme rainfall events by typhoons.

• 대한치과보존학회:학술대회논문집
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• 대한치과보존학회 2003년도 제120회 추계학술대회 제 5차 한ㆍ일 치과보존학회 공동학술대회
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• pp.566-566
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• 2003

The purpose of this in vitro study was to measure and compare the in vitro micro shear bond strengths of the following dentin bonding systems to different dentin surfaces under simulated pulpal pressure. Occlusal surfaces of 180 extracted human molars were prepared to expose the dentin surface in perpendicular to axis of tooth. Teeth were randomly assigned to 3 equal groups and subdivided into 4 equal groups. 4 adhesive systems(All Bond 2, SEbond, AdheSE, Prompt L-Pop) were used in this study.(omitted)

• 멤브레인
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• 제8권1호
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• pp.11-21
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• 1998

The study on penetrant transport in glassy polymers has been actively pursued for decades because of its growing significance in polymer processing and related applications such as not only membranes, but corrosion protective coatings, microlithography, microelectronic fabrication, etc. In membranes application of polymeric materials, successful utilization requires understanding of how solvents penetrate, swell, and sometimes dissolve polymeric materials under various environmental conditions, as their permselecdve performance is significantly affected by it. The expose of polymer membranes to solvents may result in the structural failure due to mechanical softening, embrittlement or crazing.