• 제목/요약/키워드: Surface Topography

검색결과 680건 처리시간 0.024초

대기확산의 수치모의에서 SST 효과 (SST Effect upon Numerical Simulation of Atmospheric Dispersion)

  • 이화운;원경미;조인숙
    • 한국대기환경학회지
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    • 제15권6호
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    • pp.767-777
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    • 1999
  • In the coastal region air flow changes due to the abrupt change of surface temperature between land and sea. So a numerical simulation for atmospheric flow fields must be considered the correct fields of sea surface temperature(SST). In this study, we used variables such as latent heat flux, sensible heat flux, short and long wave radiation of ocean and atmosphere which exchanged across the sea surface between atmosphere and ocean model. We found that this consideration simulated the more precise SST fields by comparing with those of the observated results. Simulated horizontal SST differences in season were 2.5~4$^{\circ}C$. Therefore we simulated the more precise atmospheric flow fields and the movement and dispersion of the pollutants with the Lagrangian particle dispersion model. In the daytime dispersion pattern of the pollutants emitted from ship sources moved toward inland, in the night time moved toward sea by land/sea breeze criculation. But air pollutants dispersion can be affected by inland topography, especially Yangsan and coastal area because of nocturnal wind speed decrease.

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차세대 리튬이온이차전지 연구에서의 원자력 현미경 활용 (Atomic Force Microscopy Applications to the Next Generation Lithium-ion Batteries)

  • 이지현;공상혁;김형우;김형석
    • 세라미스트
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    • 제22권4호
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    • pp.381-392
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    • 2019
  • Recently, demands for lithium-ion batteries (LIB) in various fields are increasing. In particular, understanding of the reaction mechanism occurring at the electrode-electrolyte surface/interface is significant for the development of advanced LIBs. Meanwhile, research and development of LIBs highly requires a new specific characterization approach. For example, atomic force microscopy (AFM) has been utilized to the LIB research field for various purposes such as investigation of topography, electrochemical reactions, ion transport phenomena, and measurement of surface potential at high resolution. Advances in the AFM analysis have made it possible to inspect various material properties such as surface friction and Young's modulus. Therefore, this technique is expected to be a powerful method in the LIB research field. Here, we review and discuss ways to apply AFM to LIB studies.

Gravure롤 코팅방식에서 비산도료에 의한 비디오 신호의 dropouts (Liquid mist and videotape signal dropouts in gravure roll coating)

  • 김명룡
    • E2M - 전기 전자와 첨단 소재
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    • 제8권5호
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    • pp.633-639
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    • 1995
  • Dropouts in magnetic media are a primary quality deficiency which is detrimental to magnetic signal quality and thus the major impediment to error-free recording, especially in high density digital recorders. The specific form of defects and causes found to be responsible for signal dropouts occurring in magnetic tape were studied. Dropout occurred when the RF signal falls to low level due to the various types of surface defects. However, the fall in the level of the RF signal in gravure roll coated tapes was most often caused by foreign particles adhering to the magnetic tape. It was also shown from the present study that scattered particles trapped under the tape surface or put on the top can lift it as it crosses the head, creating a spherical tent shaped defect and causing a temporary signal drop. Dropout producing substances were identified through optical and microchemical analyses. The results were correlated with measured electrical signal losses combined with analytical microscopy to clarify source identification of defects.

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Variations of Sea Level and Sea Surface Temperature in Korean Seas by Topex/Poseidon and NOAA

  • Yoon, Hong-Joo;Kang, Heung-Soon;Cho, Han-Keun
    • 대한원격탐사학회지
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    • 제23권1호
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    • pp.59-63
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    • 2007
  • Altimeter (Topex/Poseidon) and AVHRR (NOAA) data were used to study the variations and correlations of Sea Level (SL) and Sea Surface Temperature (SST) in the North East Asian Seas from November 1993 to May 1998. This region is influenced simultaneously to continental and oceanic climate as the border of the East Sea (Japan Sea). SL and SST have increased gradually every year because the global warming, and presented usually a strong annual variations in Kuroshio extension region with the influence of bottom topography.

푸리에 변환을 이용한 파면위상의 복구 (Fourier transform method of surface topography and interferometry)

  • 남기봉
    • 한국광학회지
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    • 제3권1호
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    • pp.20-26
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    • 1992
  • Twyman-Green형 간섭계의 시험파면의 변형을 추출하기 위하여 fourier변환을 이용하는 방법을 모사실험과 실험을 통하여 검토하였다. 대상 방법중에서는 Takeda의 방법이 변형을 추출하는 용도로 적절함이 밝혀졌다. 이 방법을 평면경에 적용하여 얻은 표면의 구조에는 curvature가 존재하며, 그 크기는 $\lambda$/6정도였다. 이 축정의 정확도는 $\lambda$/40정도로 얻어져, 기 발표된 유사연구의 결과보다 그 정도가 높음을 확인하였다.

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3축 머시닝센터와 치구를 이용한 금형의 정밀가공시의 특성해석 (Analysis of the Machinability of a Precision Machining of Molds/Dies by Using Jig and 3-Axis M/C)

  • 김병희;주종남
    • 한국정밀공학회지
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    • 제12권3호
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    • pp.119-129
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    • 1995
  • In this paper, the inclined endmilling process with a 3-axis machining center using inclined jigs is introduced for the purpose of reducing overall Dies/Molds machining time and improving the machining accuracies. In order to analyze the cutting mechanism of a given endmill more accurately, the unification of the cutting mechanism model of 3-different- kind endmills is carried out by using a nose radius as a parameter. By adding radial runouts as a parameter which influences on surface roughness, the superposition method which defines the effective cusp height superposing the cutter mark height and the conventional cusp height is advanced. And 3-D suface topography predicted in this paper looks like the surface normally observed in practice. Through machining experiments, the adequacy of the superposition method was confirmed.

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SL/SST variations and their correlations in the North East Asian Sens by remote sensing (Topex/Poseidon, NOAA)

  • Yoon, Hong-Joo
    • 한국GIS학회:학술대회논문집
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    • 한국GIS학회 2003년도 공동 춘계학술대회 논문집
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    • pp.297-299
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    • 2003
  • Altimeter(Topex/Poseidon) and AVHRR(NOAA) data were used to study the variations and correlations of Sea Level(SL) and Sea Surface Temperature (SST) in the North East Asian Seas from November 1993 to May 1998. This region is influenced simultaneously to continental and oceanic climate as the border of the East Sea(Japan Sea). SL and SST have increased gradually every year because the global warming, and presented usually a strong annual variations in Kuroshio extension region with the influence of bottom topography.

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Landsat 7 ETM+ 위성자료로부터 지형과 지표온도의 상관성 분석 (Analysis of Correlationship between Topography and Ground Surface Temperature Using Landsat 7 ETM+ Satellite Data)

  • 이진덕;방건준;한승희
    • 한국콘텐츠학회:학술대회논문집
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    • 한국콘텐츠학회 2012년도 춘계 종합학술대회 논문집
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    • pp.131-132
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    • 2012
  • 서울지역을 대상으로 하여 Landsat 7 ETM+ 영상의 열적외선 채널을 이용하여 추출한 지표온도를 추출함에 있어서 DEM데이터로 부터 추출한 경사도와 사면방향 등의 지형조건과의 상관관계를 분석하고자 하였다.

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마그네트론 스퍼터에 의한 Carbon Nitride 박막의 합성 및 특성에 관한 연구 (A Study on the Synthesis and Characterization of Carbon Nitride Thin Films by Magnetron Sputter)

  • 박구범
    • 전기학회논문지P
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    • 제52권3호
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    • pp.107-112
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    • 2003
  • Amorphous carbon nitride thin films have been deposited on silicon (100) by reactive magnetron sputtering method. The basic depositon parameters varied were the r.f. power(up to 250 W), the deposition pressure in the reactor(up to 100 mtorr) and Ar:$N_2$ gas ratio. FT-IR and X-ray photoelectron spectra showed the presence of different carbon-nitrogen bonds in the films. The surface topography of the films was studied by scanning electron microscopy(SEM) and atomic force microscopy(AFM).