• 제목/요약/키워드: grazing-incidence

검색결과 48건 처리시간 0.035초

Side Scan Sonar 실무이론과 현장조사에 적용 (Practical theory and ocean survey application of side scan sonar)

  • 김성렬;이용국;정백훈
    • 한국마린엔지니어링학회:학술대회논문집
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    • 한국마린엔지니어링학회 2006년도 전기학술대회논문집
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    • pp.201-204
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    • 2006
  • In the side scan sonar method, use is made of the back-scattering, at low grazing angles of incidence to the seabed, of relatively high-frequency acoustic waves radiated in a fan-shaped beam from a transducer contained in a towed body. The fan beam is oriented so that the wider angle is in the vertical plane (scan range) and the narrower angle in the horizontal plane (beam width) with the axis of the beam normal to the ship track. The display of the returns is usually realized as a series of closely spaced intensity-modulated lines on a paper recorder or computer screen display. In this way a two-dimensional picture of the seabed is build up.

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유전체 쐐기에 의한 물리광학해를 수정하기 위한 새 로운 급수 (Fast Converging Correction Current for the Physical Optics Edge Diffraction by a dielectric Wedge)

  • 전재영;서종화;나정웅
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 1999년도 하계종합학술대회 논문집
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    • pp.877-880
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    • 1999
  • A rigorous formulation is suggested〔l,2,3〕 in solving the scattering of plane waves by a dielectric wedge. Correcting surface currents are expanded in a Neumann series of fractional orders to meet the edge condition of static limit〔4〕. For the better converging series, the modified Neumann series satisfying the static limit edge condition and the radiation condition are suggested here for the surface currents having two different wave numbers of air and dielectric〔4〕. This representation gives accurate solutions over the whole region including the grazing incidence of the plane waves upon the dielectric wedge of large permittivities.

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방사광 이용 표면분석 총론

  • 황찬용
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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    • pp.79-79
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    • 2012
  • 방사광이 고체물리의 연구에 이용되기 시작한 60년대 말 이후부터 지난 반세기동안 방사광시설과 이를 이용한 분석 장치들은 큰 발전이 거듭되어 왔다. 90년대에는 포항가속기 연구소에서 방사광을 이용한 실험 시설이 완공되어 지난 20 여년간 이용되어 왔고 현재는 이시설이 업그레이드(PLS II) 되어 조만간 다시 이용자에게 공개될 예정이다. 연 x-선의 경우 광전자를 분석하게 되면 시료의 표면으로부터 1 nm - 수십 nm 두께의 현상에 대한 분석이 가능하다. 경 x-선(수 keV 이상의 에너지를 갖는)의 경우는 비교적 큰 penetration depth를 갖지만 grazing incidence를 이용하게 되면 수 나노 이하의 두께에서 일어나는 현상에 대한 연구가 가능하다. 본 tutorial에서는 전자의 에너지 영역인 VUV영역에서 가능한 방사광을 이용한 여러 가지 표면분석법(XPS, MCD, XAS, ARPES, SPEM, PEEM등)에 대한 세부강의를 제공하고자 한다. 총론에서는 경 x-선을 포함하는 방사광을 이용한 표면분석기술이 어디까지 발전되어 왔고 어느 수준까지 분석이 가능한지에 대한 전체적인 view를 제공하고자 한다. 본 tutorial은 이제 막 방사광을 이용한 연구를 수행하려는 연구자들, 지금까지 특정 분석기술을 사용한바 있는 연구자들, 그리고 여러 가지 방사광이용 표면분석방법에 대한 이해가 필요한 소재 혹은 소자의 개발자들에 좋은 배움의 기회가 될 것입니다.

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Real-time X-ray Scattering as a Nanostructure Probe for Organic Photovoltaic Thin Films

  • 이현휘;김효정;김장주
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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    • pp.181-181
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    • 2013
  • Recently, nanostructure and the molecular orientation of organic thin films have been largely paid attention due to its importance in organic electronics such as organic thin film transistors (OTFTs), organic light emitting diodes (OLEDs), and organic photovoltaics (OPVs). Among various methods, the diffraction and scattering techniques based on synchrotron x-rays have shown powerful results in organic thin film systems. In this work, we introduce the in-situ annealing system installed at PLS-II (Pohang Light Source II) for organic thin films by simultaneously conducting various x-ray scattering measurements of x-ray reflectivity, conventional x-ray scattering, grazing incidence wide angle x-ray scattering (GI-WAXS) and so on. Using the in-situ measurement, we could obtain real time variation of nanostructure as well as molecular orientation during thermal annealing in metal-phthalocyanine thin films. The variation of surface and interface also could be simultaneously investigated by the x-ray reflectivity measurement.

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Resistivity Variation of Nickel Oxide by Substrate Heating in RF Sputter for Microbolometer

  • Lee, Yong Soo
    • 센서학회지
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    • 제24권5호
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    • pp.348-352
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    • 2015
  • Thin nickel oxide films formed on uncooled and cooled $SiO_2/Si$ substrates using a radio frequency (RF) magnetron sputter powered by 200 W in a mixed atmosphere of argon and oxygen. Grazing-incidence X-ray diffraction and field emission scanning electron microscopy are used for the structural analysis of nickel oxide films. The electrical conductivity required for better bolometric performance is estimated by means of a four-point probe system. Columnar and (200) preferred orientations are discovered in both films regardless of substrate cooling. Electric resistivity, however, is greatly influenced by the substrate cooling. Oxygen partial pressure increase during the nickel oxide deposition leads to a rapid decrease in resistivity, and the resistivity is higher in the cooled nickel oxide samples. Even when small microstructure variations are applied, lower resistivity in favor of low noise performance is acquired in the uncooled samples.

고분자 기판 상에 Rubber-stamp-printing 방법으로 제작한 유기박막 트랜지스터에 관한 연구 (Rubber-stamp-printed Poly (3-hexylthiophene) organic field-effect transistor on a plastic substrate with high mobility)

  • 김영훈;문대규;한정인
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2005년도 춘계학술대회 논문집 디스플레이 광소자 분야
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    • pp.164-168
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    • 2005
  • We report high performance poly (3-hexylthiophene) organic field-effect transistors fabricated on a plastic substrate. The polymer active channel layer was directly printed by the rubber stamp printing method with a pre-patterned elastomer stamp. As a result. organic transistors having average field-effect mobility of 0.079 $cm^2/Vs$ and on/off ratio of $10^4{\sim}10^5$ were realized on a plastic substrate. Also, through the investigation of the molecular ordering of rubber-stamp-printed poly (3-hexylthiophene) films using synchrotron grazing-incidence X-ray diffraction measurements, the films were found to have edge-on structure which is favorable in realizing high performance organic transistors.

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Fe/MnO 다층박막에서의 $Mn^{+2}$의 자성연구 (Magnetic properties of $Mn^{+2}$ in Fe/MnO multilayers)

  • 허재혁;채동훈;박성렬;이동렬;박수현;정윤희;전인준;김동언;이기봉
    • 한국진공학회지
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    • 제8권3A호
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    • pp.213-217
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    • 1999
  • Fe/MnO multilayers with different bilayer thicknesses were grown by pulsed laser deposition method. Grazing incidence X-ray reflectivity results showed obvious multilayer Bragg peaks implying highly layered samples and, through their analysis, some structural parameters were quantiatively estimated. From the X-ray diffraction peak corresponding to MnO(111), Mn-oxide turned out to be dominantly MnO. To characterize the magnetic properties of $Mn^{+2}$, XMCD were carried out. Magnetic moments of MnO near interfaces were ordered in the opposite direction to those of Fe.

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Initial Growth and Surface Stability of 1,4,5,8,9,11-Hexaazatriphenylene-exanitrile (HATCN) Thin Film on an Organic Layer

  • Kim, Hyo Jung;Lee, Jeong-Hwan;Kim, Jang-Joo;Lee, Hyun Hwi
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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    • pp.192.2-192.2
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    • 2013
  • Crystalline order and surface stability of 1,4,5,8,9,11-hexaazatriphenylene-hexanitrile (HATCN) thin films on organic surface were investigated using grazing incidence wide angle x-ray scattering and x-ray reflectivity measurements. In the initial growth regime (less than 20 nm), HATCN molecules were stacked to low crystalline order with substantial amorphous phase. Meanwhile, a thicker film with 50 nm thickness showed high crystalline order of hexagonal phase with three different orientational domains. The domain distribution was quantitatively obtained as a function of tilted angle. By an organic-inorganic interface formation of IZO/HATCN thin film from an indium zinc oxide (IZO) electrode deposition, the surface stability of HATCN film was investigated and the sharp interface was confirmed by the x-ray reflectivity measurement.

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Synchrotron Grazing Incidence X-ray Scattering and Its Applications in Polymer Nanotechnology

  • Ree, Moon-Hor;Lee, Byeong-Du;Yoon, Jin-Hwan;Heo, Kyu-Young;Jin, Kyeong-Sik;Jin, Sang-Woo;Kim, Hyun-Chul;Kim, Gha-Hee;Choi, Seung-Chul;Oh, Weon-Tae;Park, Young-Hee;Hwang, Yong-Taek;Kim, Jong-Seong
    • 한국고분자학회:학술대회논문집
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    • 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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    • pp.120-120
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    • 2006
  • In our study grazing incidence X-ray scattering (GIXS) measurements with synchrotron radiation sources were conducted statically and in-situ for a series of nanoscale thin films prepared from nanoporous dielectrics, block copolymers, brush polymers, and molecular assemblies. All GIXS measurements were performed at the Pohang Accelerator Laboratory. The measured scattering data were analyzed in detail by using newly developed GIXS scattering theory. All GIXS results will be discussed in details with considering the materials chemistry and nanostructure formation process parameters.

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도입우에 대한 진드기매개질병의 감염실태에 관한 조사연구 (Studies on Incidence of Tick - borne Diseases in Imported Cattle in Korea)

  • 서명득;김용희;강영배;강승원
    • 대한수의사회지
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    • 제18권4호
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    • pp.19-32
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    • 1982
  • 진드기매개질병에 대한 예방대책을 수립하고 저 국내에 기도입된 소에서 출산하여 처음방목 되는 소와 신규로 도입되어 처음 방목되는 유우 및 육우를 대상으로 하여 각 지역별로 주혈원충의 감염상과 이 원충에 의한 질병의 발생실태를 조사하여 다음과 같은 결론을 얻었다. 1. 국내 도입우의 진드기매개질병에 관여하는 병원체는 Theileria sergenti, Babesia ovata Anaplasma marginate 및 Anaplasma centrale로 확인되었다. 2. 내륙의 평야지대인 경기, 충남 및 경남지역에서는 T. sergenti, 충북과 전남지역에서는 T. sergenti와 B.ovata 그리고 전북지역 (고냉지대)에서는 T. sergenti, B.ovata및 A.centrale가 각각 관여하고 있었다. 3. 대관령지역에서는 T. sergenti만이 관여하고 있었다. 4. 제주지역에서는 T. sergenti, B.ovata 및 A. .marginate가 관여하고 있었다. 5. 내륙의 진드기 서식이 높은 지역에서는 방목후 4 - 5주째에 감염강도 $109.9\~174.7$을 나타내었고 이 시기에 발병증상을 보였다. 그리고 진드기 서식이 낮은 지역에서는 방목후 $5\~6$주째에 감염강도 $31.3\~40$을 나타내었고 발병증상 없이 내과하였다. 6. 대관령 지역에서는 방목후 8주째에 감염강도 54.4-69.2를 나타내었고 이 시기에 발병 증상을 보였다. 7. 제주지역에서는 방목후 $3\~4$주째에 감염강도 33.9-42.7을 나타내었고 이 시기를 전후하여 발병증상을 보였다 . 8. 국내에 있어서 진드기 섭식이 낮은 지역과 높은 지역을 설정하였다.

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