• 한국지진공학회:학술대회논문집
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• 한국지진공학회 1998년도 추계 학술발표회 논문집 Proceedings of EESK Conference-Spring 1998
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• pp.136-143
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• 1998

Elastomeric bearing is used as one of the most useful way for isolation structures, because the horizontal stiffness is much lower than the vertical stiffness. The quality of Elastomeric bearing depends on the vulcanization procedure to manufacture, which produces the elasticity of the rubber from the compound of rubber and sulphur. The durability of Elastomeric bearing is affected by the deterioration due to ozone and ultra-violet attack. but the durability during the design life of bridges can be assured by the sufficient size of the bearing in spite of the deterioration in surface. In the design criteria of Elastomeric bearing, the stability of the bearings is evaluated by shear strain due to compression, lateral displacement, and rotation. The question how soft rubber can sustain heavy structure is now able to be solved by Ultimate capacity test of Laminated elastomeric Bearings, which results 1,200kg/$\textrm{cm}^2$ of the max. compressive stress and this shows what a sufficient safety factor Elastomeric bearing has!

• 대한화장품학회:학술대회논문집
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• 대한화장품학회 1992년도 자외선 차단 화장품의 SPF에 관한 심포지움(대한화장품학회)
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• pp.97-114
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• 1992

In these days sun products are developed and produced by the cosmetic scientists in the world. Peoples need strongly to protect themselves from the hazardous UV rays dued to the destruction of ozone layer. Therfore, we, cosmetic scientists must have an effort to produce the more effective goods. In this article the market survey of sun-products as well as the currency of sunscreen agents was investigated. It was found that Benzophenone - 3 and Ocytyl methoxy cinnamate were widely used. The lotions, using Benzophenone - 3 as the chemical agents, and TiO$_2$and micro TiO$_2$ as the physical agents, were measured the UV-Spectrum in the Dilution and Application method. Photoprotective activity of chemical agents can usually be measured in solution state. However, that of the insoluble physical agents such as TiO$_2$is hardly measured in this state. Photoprotective ability of the insoluble physical agents was able to be measured by application of lotions to the surface of UV cells. It was found by this method that micro TiO$_2$showd stronger UV scattering effect than TiO$_2$in this method.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집
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• pp.281-283
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• 2001

Bi$_2$Sr$_2$CuO$\_$x/(Bi-2201) thin films were fabricated layer-by-layer deposition using an ion beam sputtering method. 10 wt% and 90 wt% ozone mixed with oxygen were used ultraviolet light irradiation to assist oxidation. At early stages of the atomic layer by layer deposition, two dimensional epitaxial growth which covers the substrate surface would be suppressed by the stress and strain caused by the lattice misfit, then three dimensional growth takes place. Since Cu element is the most difficult to oxidize, only Sr and Bi react with each other predominantly, and forms a buffer layer on the substrate in an amorphous-like structure, which is changed to SrBi$_2$O$_4$ by in-situ anneal.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 추계학술대회 논문집 전기물성,응용부문
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• pp.119-121
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• 2002

$Bi_2Sr_2CuO_x$ thin films were fabricated by atomic layer-by-layer deposition using an ion beam sputtering method, 10 wt% and 90 wt% ozone mixed with oxygen were used with ultraviolet light irradiation to assist oxidation. At early stages of the atomic layer by layer deposition, two dimensional epitaxial growth which covers the substrate surface would be suppressed by the stress and strain caused by the lattice misfit, then three dimensional growth takes place. Since Cu element is the most difficult to oxidize, only Sr and Bi react with each other predominantly, and forms a buffer layer on the substrate in an amorphous-like structure, which is changed to $SrBi_2O_4$ by in-situ anneal.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제38회 동계학술대회 초록집
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• pp.56-56
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• 2010

We report a low-temperature fabrication of organic/inorganic nanohybrid dielectrics for organic thin film transistors. The self-assembled organic layers (SAOLs) were grown by repeated sequential adsorptions of C=C-terminated alkylsilane and metal (Al or Ti) hydroxyl with ozone activation, which was called "molecular layer deposition (MLD)". The $TiO_2$ and $Al_2O_3$ inorganic layers were grown by ALD, which relies on sequential saturated surface reactions resulting in the formation of a monolayer in each sequence and is a potentially powerful method for preparing high quality multicomponent superlattices. The MLD method combined with ALD (MLD-ALD) was applied to fabricate SAOLs-$Al_2O_3$-SAOLs-$TiO_2$ nanohybrid superlattices on polymer substrates at relatively low temperature. The MLD method is an ideal fabrication technique for various flexible electronic devices.

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2002년도 춘계학술대회 논문집
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• pp.73-74
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• 2002

Active upwelling air motion in every summer over the Tibetan plateau is an essential process controlling activities of asian summer monsoon which affects water cycle and precipitation in eastern Asia. Large heating rate of surface air on the high plateau with average height of 4000m is considered to cause such large scale upwelling over the plateau. (omitted)

• 접착 및 계면
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• 제23권4호
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• pp.108-115
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• 2022

본 연구에서는 표면처리된 Cu 리드프레임과 에폭시 컴포지트의 접착강도를 향상시키기 위하여 신규 고분자 접착증진제인 poly(itaconic acid-co-acrylamide) (IAcAAM)를 합성하였다. 이타콘산과 아크릴아마이드를 포함하는 IAcAAM은 라디칼 수성 중합을 통해 제조되었다. IAcAAM의 구조 및 물성은 FT-IR, ¹H-NMR, GPC 및 DSC로 분석하였다. Cu 리드프레임의 표면은 고온, 알칼리, UV 오존으로 처리하였다. 표면처리 후 Cu 리드프레임의 접촉각이 감소함에 따라 Cu 리드프레임/에폭시 컴포지트의 접착강도는 증가하였다. 에폭시 혼합물에 IAcAAM을 첨가함에 따라 Cu 리드프레임/에폭시 컴포지트의 접착강도가 증가하였다. 또한, 에폭시 혼합물에 실리카 함량이 증가할수록 Cu 리드 프레임과 에폭시 컴포지트의 접착강도는 약간 감소하는 경향을 나타내었다.

• 대한원격탐사학회지
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• 제33권2호
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• pp.135-147
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• 2017

본 연구에서는 처음으로 한반도 서울지역에서 OMI (Ozone Monitoring Instrument) 센서로 관측된 대류권 이산화질소 칼럼농도를 이용하여 OMI 센서의 관측시간인 13:45에서의 월 평균 및 일별 위성 지표 이산화질소 혼합비를 추정하였다. 본 연구에서는 세 가지 회귀모델들이 이용되었다. 첫 번째 회귀모델(M1)은 OMI 대류권 이산화질소 칼럼농도와 지점 측정값과의 선형회귀를 통한 회귀계수로 구성되어있다. 두번째 회귀모델(M2)은 OMI 대류권 이산화질소 칼럼농도와 AIRS (Atmospheric Infrared Sounder) 센서로 관측한 행성경계층 높이, 온도, 압력 자료 모두가 반영된 회귀모델이다. 세 번째 회귀모델(M3M, M3D)은 다중회귀모델로서 앞서 고려된 이산화질소 칼럼농도와 행성경계층 높이와 다양한 기상변수를 추가적으로 반영하는 회귀모델이다. 본 연구에서는 2009년에서 2011년까지를 회귀모델의 훈련기간으로 하여서 각 회귀식의 회귀계수를 도출하였으며 2012년도는 검증기간으로서 훈련기간에 도출된 회귀모델들의 성능을 평가하였다. 회귀모델들로 추정된 월 평균 지표 이산화질소 혼합비와 지점 관측소에서 지점 측정장비로 측정된 월평균 지표 이산화질소 혼합비와 가장 높은 상관성(avg. R = 0.77)을 보이는 회귀분석방법은 다중회귀분석방법(M3M)이다. 또한, 회귀모델들로 추정된 13:45에서의 일 지표 이산화질소 혼합비와 지점 관측소에서 지점장비로 측정된 지표 이산화질소 혼합비와 가장 좋은 상관성(avg. R = 0.55)을 보인 것도 다중회귀분석방법(M3D)이다. 회귀모델들로 추정된 지표 이산화질소 혼합비는 지점 측정값에 비해 과소추정 되는 경향이 나타났다. 회귀모델들로 추정된 지표 이산화질소 혼합비를 평가하기 위해 지점 측정값과의 RMSE (Root Mean Square Error), mean bias, MAE (Mean Absolute Error), percent difference와 같은 통계분석을 실시하였다. 본 연구는 위성을 통한 지표 이산화질소 혼합비 산출 가능성을 보여준다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.434-435
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• 2012

Plasma enhanced chemical vapor deposition (PECVD) silicon dioxide thin films have many applications in semiconductor manufacturing such as inter-level dielectric and gate dielectric metal oxide semiconductor field effect transistors (MOSFETs). Fundamental chemical reaction for the formation of SiO2 includes SiH4 and O2, but mixture of SiH4 and N2O is preferable because of lower hydrogen concentration in the deposited film [1]. It is also known that binding energy of N-N is higher than that of N-O, so the particle generation by molecular reaction can be reduced by reducing reactive nitrogen during the deposition process. However, nitrous oxide (N2O) gives rise to nitric oxide (NO) on reaction with oxygen atoms, which in turn reacts with ozone. NO became a greenhouse gas which is naturally occurred regulating of stratospheric ozone. In fact, it takes global warming effect about 300 times higher than carbon dioxide (CO2). Industries regard that N2O is inevitable for their device fabrication; however, it is worthwhile to develop a marginable nitrous oxide free process for university lab classes considering educational and environmental purpose. In this paper, we developed environmental friendly and material cost efficient SiO2 deposition process by substituting N2O with O2 targeting university hands-on laboratory course. Experiment was performed by two level statistical design of experiment (DOE) with three process parameters including RF power, susceptor temperature, and oxygen gas flow. Responses of interests to optimize the process were deposition rate, film uniformity, surface roughness, and electrical dielectric property. We observed some power like particle formation on wafer in some experiment, and we postulate that the thermal and electrical energy to dissociate gas molecule was relatively lower than other runs. However, we were able to find a marginable process region with less than 3% uniformity requirement in our process optimization goal. Surface roughness measured by atomic force microscopy (AFM) presented some evidence of the agglomeration of silane related particles, and the result was still satisfactory for the purpose of this research. This newly developed SiO2 deposition process is currently under verification with repeated experimental run on 4 inches wafer, and it will be adopted to Semiconductor Material and Process course offered in the Department of Electronic Engineering at Myongji University from spring semester in 2012.

• 항공우주기술
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• 제13권2호
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• pp.80-86
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• 2014

본 연구에서는 다목적실용위성 3호 영상을 이용하여 지표면 상의 정규식생지수 비교 분석 하고자 한다. 산출된 다목적실용위성 3호의 정규식생지수 비교 분석을 위해 동일 지점 최소 관측 시간 오차를 가지는 고해상도 GeoEye 영상이 사용되었다. 먼저, 각 밴드별 분광 정도 산출을 위해 대기 보정이 수행되었다. 대기 보정 수행을 위한 기하 정보는 다목적실용위성 3호 보조자료에 포함된 태양천정각, 태양방위각, 위성천정각, 위성방위각, 날짜 정보이다. 그리고 대기 요소에 의한 감쇄, 산란, 흡수 정보를 물리적으로 계산하기 위해 수증기량, 오존량, 에어러솔 정보가 적용되었다. 일반적으로 정확한 대기정보를 얻기 위해서는 현장관측자료가 중요하지만, 본 연구에서는 MODIS atmospheric products를 사용하였고, 대기보정 모델에서 산출된 지면 반사도는 식생지수 산출에 사용되었다.