• Proceedings of the KAIS Fall Conference
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• 2003.06a
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• pp.119-121
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• 2003

마이크로 가스센서를 개발하기 위하여 가장 핵심적인 부품인 마이크로 핫플레이트에 대한 열전달을 해석하였다. 상용 열유동 해석 전용 프로그램인 FUENT를 이용하여 발열부와 주위의 실리콘 기판의 온도분포를 구하였다. 발열부에서는 전기저항에 의해서 일정한 양의 열이 균일하게 발생한다고 가정하고 그 열이 실리콘 기판의 끝을 통하여 빠져나간다고 가정하여 정상상태의 온도분포를 구하였다. 해석한 온도분포를 이용하여 균일한 온도분포를 얻을 수 있도록 발열선의 배치를 변화시켜가며 마이크로 핫플레이트의 설계를 완성하였다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.11a
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• pp.289-292
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• 2009

The fabrication method of glass bipolar plates for micro PEM fuel cell application has been established and performance evaluation has been carried out. The advantages of glass bipolar plates for micro PEM fuel cells are light weight, high chemical resistivity, and easy manufacture. The MEMS fabrication process of anisotropic wet etching, thermal & UV bonding along with metal layer deposition has been introduced. From performance evaluation, it was shown that the micro fuel cell with a metal layer deposited on the reactive area yielded higher power density than the one without it. But both power densities of the two cases showed out to be adequate with the current status of micro fuel cell technology.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.5 no.2
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• pp.132-136
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• 2004

A flat type $NO_2$ micro gas sensor was fabricated by MEMS technology. In order to heat up gas sensing material such as $WO_3$ to a target temperature, a micro hotplate was built on the gas sensor. The temperature distribution of micro gas sensor was analyzed by a CFD program, FLUENT. The results showed that the temperature of silicon wafer base was almost similar to that of the room temperature, which indicates that the heat generated at the micro hotplate heated up effectively the sensing material and its thermal isolation was kept. The uniformity of temperature on the sensing material can be improved by modifying the shape of micro hotplate.

• Journal of the Korean Electrochemical Society
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• v.7 no.2
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• pp.100-107
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• 2004

The nano or micro sized structures of conducting polymer had been prepared by synthesizing the desired polymer within the pores of template of nano or micro porous membrane filter. In this study, we had tried to fabricate conducting polymer microstructures on an electrode by using electrochemical deposition adopting template synthesis. Our attention was focused on two different things, attaching template on the electrode and fabricating microstructures only at limited areas of the electrode. A conducting polymer, PEDiTT (poly 3,4-ethylenedithi-athiophene) solution was blended with PVA(polyvinyl alcohol) solution and used as an conducting adhesive. After attaching template membrane, the electrode were immersed in 0.5M pyrrole in 0.1M KCI solution, and electrochemical polymerization was performed. The growth process of the microstructures studied by SEM. The electrochemical fabrication of conducting polymer was performed by using two-electrode system. A large working electrode and a micro scale disc electrode were used for the confined area synthesis. Polymerization potential was 4V in an electrolytic solution made of KCI in deionized water. The optimum polymerization conditions were, i.e. (4V/100sec) for $250{\mu}m$ electrode and (6V/30 sec) for $10{\mu}m$ electrode.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.10a
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• pp.103-104
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• 2012

• Journal of the korean veterinary medical association
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• v.24 no.4
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• pp.230-236
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• 1988

• Journal of the Korea Concrete Institute
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• v.27 no.4
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• pp.387-397
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• 2015

In the present study, to enhance the constructability, a composite slab system using deck plate and micro steel fiber concrete was studied. In the proposed slab system, on-situ re-bar placement is not required. Steel fibers replace the temperature reinforcement. The present study focused on the crack control at the slab top in the continuous composite slab without spliced bars. Eight continuous slabs with various parameters were tested under vertical loading. The test parameters were the amount and types of micro steel fibers, types of deck plate, and the use of top bars in the continuous slab. To evaluate the crack resistance of the slabs, crack widths were measured in the continuous slabs. The test results showed that although the top spliced bars were not used, cracking were restrained by large flexural stiffness of the composite sections.

• Proceedings of the Optical Society of Korea Conference
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• 2007.02a
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• pp.199-200
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• 2007

UV 처리 광학 접착제를 가지고 단일 포토리소그라피 공정을 사용하여 마이크로 렌즈를 제작하였다. 먼저 유리판 위에 자외선 처리 광학 접착제를 코팅 한 후 UV 노광하고 아세톤에서 현상 후 핫플레이트에서 유리전이 온도 이상에서 열적 재흐름이 일어나도록 하여 마이크로 렌즈를 만드는데 성공하였다 이를 실제 LED 소자 위에서 마이크로 렌즈를 만들어 보고 LED의 외부 추출 효율이 높아지는지를 실험하였다. 또한 기존의 UV 처리 광학 접착제에 나노 입자을 첨가하여 굴절률을 더 높여 마이크로 렌즈를 만드는 실험을 하였다.

• Resources Recycling
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• v.29 no.1
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• pp.35-42
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• 2020

Even asbestos-containing waste (ACW) are highly harmful to humans, it continues being produced due to the massive disposal of asbestos-containing products. A development of asbestos detoxification and recycling technologies is required. Heat treatment using microwave is the most efficient method for ACW detoxification. However, microwave heat treatment method has the limitation that asbestos does not absorb microwave at room temperature. That is why, in this study, ACW was detoxified by microwave heat treatment adding the ACW between SiC plates, which are inorganic heating elements that absorb microwaves at room temperature. In order to improove the heat transfer, ACW was crushed and pulverized and then heated using microwave. Microwave heat treatment temperature and time variables were adjusted to investigate the detoxification properties according to heat treatment conditions. After heat treatment, treated ACW was analyzed for detoxification properties through crystal structure and microstructure analysis using X-ray diffraction (XRD) and scanning electron microscopy (SEM). Microwave heat treatment method using SiC plate can be heated up to the target temperature within a short time. Finally, complete asbestos detoxification was confirmed from the crystal structure and the microstructure when the microwave heat treatment was performed at 1,200℃ for at over 60 minutes and at 1,300℃ for at over 10 minutes.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2002.11a
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• pp.81-85
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• 2002

전기 전자 제품에 사용되는 반도체 칩이나 부품들은 작동시 발열을 하게 되며 이러한 열은 적절히 제거되지 않은 경우 전기 전자 제품의 오작동을 유발시키는 요인이 된다. 발열부품이 작동할 때 발생되는 열을 제거하기 위해서 히트싱크나 냉각팬과 같은 구조를 발열 부품 장착시 같이 설치하는 방법이 일반적으로 사용되는 냉각구조 형태지만 이와 같은 냉각 구조는 최근의 전기 전가 제품의 소형화 추세에 부응하는데는 한계가 있다. 따라서 이러한 냉각 구조의 한계를 보완하기 위한 방안으로써 소형화한 히트싱크, 즉 두께와 방열의 중요 요인이 되는 히트싱크의 방열핀의 크기를 나노미터 단위에서 밀리미터 단위로 제조한 마이크로 히트 싱크를 제조하여 그 효용성에 대해 연구하고자 하였다. 마이크로 히트싱크의 제조는 균일한 포어를 포함한 폴리머 멤브레인에 열전도성이 뛰어난 금속을 무전해 도금하는 방법으로 제조하였으며 주사현미경으로써 관찰하였다.