• 대한기계학회논문집B
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• 제33권9호
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• pp.709-717
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• 2009

Heat transfer rate is a very important factor for the performance of a steam reformer because a steam reforming reaction is an endothermic reaction. Coaxial cylindrical reactor is the reactor design which can improve the heat transfer rate. Temperature, fuel conversion and heat flux in the coaxial cylindrical steam reformer are studied in this paper using numerical method under various operating conditions. Langmuir-Hinshelwood model and pseudo-homogeneous model are incorporated for the catalytic surface reaction. Dominant chemical reactions are assumed as a Steam Reforming (SR) reaction, a Water-Gas Shift (WGS) reaction, and a Direct Steam Reforming (DSR) reaction. Although coaxial cylindrical steam reformer uses 33% less amount of catalyst than cylindrical steam reformer, its fuel conversion is increased 10 % more and its temperature is also high as about 30 degree. There is no heat transfer limitation near the inlet area at coaxial-type reactor. However, pressure drop of the coaxial cylindrical reactor is 10 times higher than that of cylindrical reactor. Operating parameters of coaxial cylindrical steam reformer are the wall temperature, the inlet temperature, and the Gas Hourly Space Velocity (GHSV). When the wall temperature is high, the temperature and the fuel conversion are increased due to the high heat transfer rate. The fuel conversion rate is increased with the high inlet temperature. However, temperature drop clearly occurs near the inlet area since an endothermic reaction is active due to the high inlet temperature. When GHSV is increased, the fuel conversion is decreased because of the heat transfer limitation and short residence time.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 C
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• pp.1579-1581
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• 1996

The high temperature characteristics of SOI BMFET are analyzed by the numerical simulation and compared with MOS-gated SOI power devices at high temperatures. The proposed SOI BMFET combines bipolar operation in the on-state with unipolar FET operation in the off-state, so that it may be suitable for high temperature operation without any significant degradation of performance such as the leakage current and blocking capability. The simulation results show that SOI BMFET with a higher doped n-resurf layer is the most promising device far high temperature application as compared with MOS-gated SOI power devices, exhibiting the low on-state voltage drop as well as the excellent forward blocking capability at high temperature.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2012년도 춘계학술발표대회
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• pp.64.1-64.1
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• 2012

Next generation displays such as high performance LCD, AMOLED, flexible display and transparent display require specific TFT back-planes. For high performance TFT back-planes, low temperature poly silicon (LTPS), and metal-oxide semiconductors are studied. Flexible TFT backplanes require low temperature processible organic semiconductors. Not only development of active semiconducting materials but also design and synthesis of semiconductor corresponding gate dielectric materials are important issues in those display back-planes. In this study, we investigate the high heat resistant polymeric gate dielectric materials for organic TFT and inorganic TFT with good insulating properties and processing chemical resistance. We also controlled and optimized surface energy and morphology of gate dielectric layers for direct printing process with solution processible organic and inorganic semiconductors.

• 한국산학기술학회논문지
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• 제16권6호
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• pp.3714-3721
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• 2015

서셉터 히터에서 쉬스 열선을 사용하는 방법이 일반화되어 있지만, 대면적 초고온 조건에서는 서셉터의 온도 균일도 성능 저하의 문제가 있다. 본 연구에서는 온도균일도 성능을 향상시킬 수 있도록 판형 형태의 열선을 기본으로 새로운 서셉터를 설계하여 프로토타입을 개발하였다. 표면 온도 $450^{\circ}C$의 고온에서 1.4% 이내로 온도 균일도가 시제작된 서셉터에서 검증될 수 있었다. 또한 온도 학습 데이터를 이용하여 측정 온도 데이터를 예측할 수 있는 커널 회귀 알고리즘을 개발하고, 이러한 예측 데이터와 측정 데이터의 비교 분석으로 균일도 측정 온도의 신뢰성을 확인할 수 있었다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2005년도 춘계 학술기술논문발표대회 논문집
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• pp.179-183
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• 2005

In apply roof waterproof system using of synthetic high polymer sheet for rooftop measure physical performance (tension$\cdot$tearing ability, temperature relativity, heating stretch performance, junction performance, wind resistance test) by various test environment condition waterproof test of structure and performance of construction work aspect, present suitable form of construction work under these environment. Also, wish to improve durability of concrete structure as that examine in priority about adhesion method and joint junction method with waterproof out surface, and present new direction about roof system application of waterproofing method for rooftop.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권2호
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• pp.1699-1702
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• 2007

We will discuss encapsulation of OLEDs on both flexible and rigid glass substrates. Accelerated testing at 6CC/90RH and 85C/85RH is compared and acceleration factors for OLED and Calcium test samples are discussed.We have tested the stability and performance of our barrier coating to much higher temperatures: up to 140 C. Water Vapor Transmission rates at temperatures from 60 to 140 C are presented. Rates and methods for low cost manufacturing on a large scale are analysed

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.223-226
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• 2003

We have developed flexible MIM LCDs by using plastic film substrate. MIM array and cells were fabricated with low temperature process and material technology. As an insulator of MIM, SiNx was introduced at the low temperature allowable for plastic substrate. The fabricated MIM devices show high electrical performance for LC driving. We discuss its process and characteristics.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2008년도 추계 학술발표회 제20권2호
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• pp.497-500
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• 2008

본 연구에서는 보통강도 고유동 자기충전 콘크리트의 수화발열 특성을 알아보기 위하여 미소수화열 시험 및 간이 단열에 의한 콘크리트 온도 상승량 실험을 실시하였다. 미소수화열 시험을 실시한 결과 석회석미분말 및 플라이애시를 혼화재로 사용한 고유동 자기충전 콘크리트는 단위시멘트량 감소로 수화발열량이 감소하였다. 간이 단열에 의한 콘크리트 온도 상승량을 측정한 결과 분체량이 많은 고유동 자기충전 콘크리트가 혼화재의 영향으로 온도저감 성능이 우수 하며, 3성분계 고유동 자기충전 콘크리트의 경우 일반콘크리트와 유사한 온도상승속도를 나타내었다. 이러한 결과 고유동 자기충전 콘크리트가 일반콘크리트보다 상대적으로 높은 단위 분체량에 대한 온도저감 성능이 우수 하며, 설계기준강도 30MPa의 3성분계가 2성분계 고유동 자기충전 콘크리트보다 온도저감 및 초기 수화발현에 유리할 것으로 판단된다.

• 한국주거학회논문집
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• 제16권4호
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• pp.81-89
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• 2005

The purpose of this thesis is thermal performance simulation about various type that can apply in the high-rise residential building to estimate condensation performance of window that is consisted of frame and glazing in curtain wall. The result of this thesis are summarized as follows. First, condensation occurrence point when relative humidity is $30{\cdot}40{\cdot}50\%$ is shortest Low-e double glass. Difference by type of gas and spacer was a little by $2{\~}6$ cm, among it, the case that apply krypton in gas and the case that apply double seal in spacer were less condensation occurrence distribution. Second, when analyzed improved proposal of window and existing plan through simulation, improved proposal is superior from general side of the interior and exterior temperature, thermal break surrounding temperature and temperature of frame end, condensation occurrence point etc. Therefore, if it was used improved proposal with effect that improve in curtain wall of high-rise residential building, it may improve window condensation performance of curtain wall.

• Journal of international Conference on Electrical Machines and Systems
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• 제1권4호
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• pp.498-504
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• 2012

The water-cooled Permanent Magnet Linear Synchronous Motor (PMLSM) has a wide range of applications due to high efficiency, high thrust force density and high acceleration. In order to ensure normal operation and maximum output, both the magnetic and thermal performance are vital to be considered. Based on ANSYS software, electromagnetic and thermal finite-element analysis (FEA) models of a 14-pole, 12-slot water-cooled PMLSM are erected adopting suitable assumptions. Firstly, the thrust force and force ripple with different current densities are calculated. Secondly, the influence of different water flow on the motor heat dissipation and force performance under different operationional conditions are investigated and optimized. Furthermore, for continuous operation, the temperature rise and thrust feature are studied under the rated load 8A, the proper temperature $120^{\circ}C$ and the limited temperature $155^{\circ}C$. Likewise, for short-time operation, the maximum duration is calculated when applied with a certain large current. Similarly, for intermittent operation, load time as well as standstill time are determined with the optimal current to achieve better thrust performance.