• 제목/요약/키워드: $DO_3SE$

검색결과 586건 처리시간 0.023초

세한도(歲寒圖)를 통해 본 공간의 문화 연구 ('Cultural study' of the Space in "SE HAN DO")

  • 고인룡;동재욱
    • 한국디지털건축인테리어학회논문집
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    • 제3권2호
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    • pp.14-19
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    • 2003
  • In this paper, I tried to apply the viewpoint and the method of "Cultural Study" to the analysis of a Architecture. "SE HAN DO(歲寒圖/ Jeonghee Kim 金正喜/ 1844)", the masterpiece of the "literary artist's paintings"(文人畵) is used as a 'TEXT‘(: parole) and analysed to show how artist's value and social-cultural ideology (as a 'CONTEXT':langue) are projected to the space and architectural vocabulary.

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Positional uncertainties of cervical and upper thoracic spine in stereotactic body radiotherapy with thermoplastic mask immobilization

  • Jeon, Seung Hyuck;Kim, Jin Ho
    • Radiation Oncology Journal
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    • 제36권2호
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    • pp.122-128
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    • 2018
  • Purpose: To investigate positional uncertainty and its correlation with clinical parameters in spine stereotactic body radiotherapy (SBRT) using thermoplastic mask (TM) immobilization. Materials and Methods: A total of 21 patients who underwent spine SBRT for cervical or upper thoracic spinal lesions were retrospectively analyzed. All patients were treated with image guidance using cone beam computed tomography (CBCT) and 4 degrees-of-freedom (DoF) positional correction. Initial, pre-treatment, and post-treatment CBCTs were analyzed. Setup error (SE), pre-treatment residual error (preRE), post-treatment residual error (postRE), intrafraction motion before treatment (IM1), and intrafraction motion during treatment (IM2) were determined from 6 DoF manual rigid registration. Results: The three-dimensional (3D) magnitudes of translational uncertainties (mean ${\pm}$ 2 standard deviation) were $3.7{\pm}3.5mm$ (SE), $0.9{\pm}0.9mm$ (preRE), $1.2{\pm}1.5mm$ (postRE), $1.4{\pm}2.4mm$ (IM1), and $0.9{\pm}1.0mm$ (IM2), and average angular differences were $1.1^{\circ}{\pm}1.2^{\circ}$ (SE), $0.9^{\circ}{\pm}1.1^{\circ}$ (preRE), $0.9^{\circ}{\pm}1.1^{\circ}$ (postRE), $0.6^{\circ}{\pm}0.9^{\circ}$ (IM1), and $0.5^{\circ}{\pm}0.5^{\circ}$ (IM2). The 3D magnitude of SE, preRE, postRE, IM1, and IM2 exceeded 2 mm in 18, 0, 3, 3, and 1 patients, respectively. No association were found between all positional uncertainties and body mass index, pain score, and treatment location (p > 0.05, Mann-Whitney test). There was a tendency of intrafraction motion to increase with overall treatment time; however, the correlation was not statistically significant (p > 0.05, Spearman rank correlation test). Conclusion: In spine SBRT using TM immobilization, CBCT and 4 DoF alignment correction, a minimum residual translational uncertainty was 2 mm. Shortening overall treatment time and 6 DoF positional correction may further reduce positional uncertainties.

CdSe 나노 입자의 이방성 구조 제어 및 특성연구 (Preparation and Characteristics of Elongated CdSe nanoparticles)

  • 김신호;박명국;김양도
    • 한국분말재료학회지
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    • 제15권3호
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    • pp.210-213
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    • 2008
  • Elongated CdSe nanoparticles with a diameter of 3-7nm have been successfully synthesized using two surfactants of trioctylphospine (TOP) and hexadecylamine (HDA) at $160^{\circ}C$. The formation of elongated CdSe nanoparticles is possibly due to the cooperative effects from both the different binding capability of two surfactants (TOP and HDA) and intrinsically anisotropic crystal structure of the CdSe. The electron diffraction pattern of CdSe nanoparticles revealed the formation of wurzite phase. The CdSe samples showed red-shifted wavelength from 560 to 580nm with increasing the refluxing time due to the gradual growth of CdSe nanoparticles. The relatively broad absorption band can be attributed to the surface state of CdSe nanoparticles. The possible formation mechanism of elongated CdSe nanoparticles was proposed and the characteristics of CdSe have been discussed as well.

$80^{\circ}$로 증착된 비정질 $Ge_{25}Se_{75}$ 박막의 두께변화에 관한 연구 (A Study on the variation of thickness in $80^{\circ}$ Deposited a-Ge$Ge_{25}Se_{75}$ films)

  • 엄정호;김태완;정홍배
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1988년도 추계학술대회 논문집
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    • pp.82-85
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    • 1988
  • In the present study, we have investigated a novel photothermal imaging technique in $80^{\circ}$ deposited Ge Se film which do not utilize silver and deposited a-$Ge_{25}Se_{75}$ films was measured with the exposure time and annealing time. The results showed that the maximum changing rate of thickness was 3% in exposured film and 14% in postexposure annealing film.

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Zinc Blende 구조를 가지는 ZnSe 결정의 밴드 특성에 관한 연구 (A Study on the Band Characteristics of ZnSe Thin Film with Zinc-blende Structure)

  • 박정민;김환동;윤도영
    • 전기화학회지
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    • 제14권3호
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    • pp.145-151
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    • 2011
  • ZnSe는 가시광선 영역에서 넓은 밴드갭을 가지고 있는 II-VI족 화합물 반도체 소자로서 레이저 다이오드, 디스플레이 그리고 태양전지와 같은 다양한 응용분야에 적용되고 있다. 본 연구에서는 전기화학적 전착방법을 이용하여 ITO 전극상에 ZnSe 박막을 합성하여, XRD와 SEM으로 ZnSe 결정의 합성과 zinc blende 구조의 형태를 관측하였고, UV 분광기를 활용하여 밴드갭을 측정한 결과 2.76 eV이었다. 또한, 분자동역학에서 활용되는 밀도범함수 이론 (DFT, Density Functional Theory)을 도입하여 ZnSe 결정에 대한 밴드 구조의 해석을 수행하였다. Zinc blende구조를 갖는 ZnSe 결정에 대하여 LDA (Local Density Approximation), PBE (Perdew Burke Ernzerhof), 그리고 B3LYP (Becke, 3-parameter, Lee-Yang-Parr) 범함수를 이용하여 밴드구조와 상태밀도 (Density of State)를 모사하였다. 각각의 경우에 대해 에너지 밴드갭을 구한 결과, B3LYP 범함수로 해석한 경우에 실험치와 근사치인 2.65 eV의 밴드갭을 보여주었다.

초음파 화학법에 의한 CdSe 나노 입자의 합성 (Sonochemical Synthesis of CdSe Nanoparticles from Mixed Aqueous Solution)

  • 성명석;이윤복;김용진;김영석;김양도
    • 한국재료학회지
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    • 제16권3호
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    • pp.198-202
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    • 2006
  • Cadmium selenide (CdSe) nanoparticles with the diameter of about 3.4nm have been synthesized from the mixed aqueous solution of distilled water and diethanolamine at room temperature. The cadmium chloride ($CdCl_2$), sodium selenosulfate ($Na_2SeSO_3$) were used as the cadmium and selenium source, respectively. The properties of CdSe nanoparticles were characterized by using transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and UV-Vis measurements. CdSe nanoparticles were analyzed to be cubic phase with the absorption excition peaks between 540 and 600 nm. CdSe nanoparticles also showed red-shifted excition peaks with increasing the sonication time. This paper mainly presents the sonication effects on the formation of CdSe nanoparticles prepared from the mixed aqueous solution of distilled water and diethanolamine.

태양전지용 CdSe 나노입자의 합성 (Preparation and Characterization of CdSe nanoparticle for Solar Cell application)

  • 김신호;박명국;이보람;이현주;김양도
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2007년도 추계학술대회 논문집
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    • pp.318-321
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    • 2007
  • CdSe nanoparticles were prepared by chemical solution methods using $CdCl_2{\cdot}4H_2O$ (or $Cd(NO_3)_ 2{\cdot}4H_2O$) and $Na_2SeSO_3$. The characteristics of CdSe nanoparticles were controlled by the react ion time, reaction temperature and reaction method as well as the surfactants. Cetyltrimethyl ammonium bromide(CTAB) was used as a capping agent to control the chemical reactions in aqueous solution. Polyvinylalcohol(PVA) was used as a templet in sono-chemical method. CdSe nanoparticles synthesized in aqueous solution showed homogeneous size distribution with relatively stable surface. CdSe nanoparticles synthesized in non-aqueous solution containing diethanolamine(DEA) showed the structure transformation from cubic to hexagonal as the reduction temperature increased from 80 to $160^{\circ}C$. Core shell CdSe was synthesized by sono-chemical method. Characteristics of CdSe nanoparticles were analyzed using transmission electron microscopy(TEM), x-ray photoelectron spectroscopy(XPS), x-ray diffraction(XRD), UV-Vis absorption spectra, fourier transform infrared spectroscopy(FT-IR) and photoluminescence spectra spectroscopy(PL). This paper presents simple routes to prepare CdSe nanoparticles for solar cell applications.

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승화법에 의한 CdSe 성장과 특성 (Growth and characterites for CdSe single crystal grown by using sublimation method)

  • 홍광준;백승남;;김도선
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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    • pp.180-181
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    • 2006
  • CdSe single crystal was grown by sublimation method in the two-step vertical electric furnace. This CdSe single crustal had hexagonal structure whose lattice constants of $a_0$ and $c_0$ were measured $4.299\;{\AA}$ and $7.009\;{\AA}$ by extrapolation method, respectively. CdSe single crystal was n-type semiconductor values were measured from Hall data by Van der Pauw method in the room temperature. Mobility tends to increase in proportion to $T^{3/2}$ from 33K to 130K due to impurity scattering. but mobility tends to decrease in proprtion to $T^{-3/2}$ from 130K to 293K due to lattice scattering. CdSe thin film was made by electron beam evaporation technique had also hexagonal structure. The grain size of this thin film was grown to $1{\mu}m$ as a result of annealing in the vapor of Ar or Cd. Annealde CdSe thin film was n-type semiconductor whose carrier density had about $7{\times}10^{12}cm^{-3}$ and its mobility had about $1.6{\times}10^3cm^2/V$ sec at room temperature.

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PVA 함유 수용액으로부터 초음파 조사에 의한 CdSe 중공 입자의 합성 (Synthesis of hollow Sphere CdSe in PVA Aqueous Solution by Using Ultrasonic Irradiation)

  • 박명국;이윤복;김용진;김인배;김양도
    • 한국세라믹학회지
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    • 제44권2호
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    • pp.84-88
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    • 2007
  • CdSe hollow spheres with the diameter of about 30-50 nm were synthesized after ultrasonic irradiation in the presence of $Cd(NO_3)_2,\;Na_2SeSO_3$, and polyvinylalcohol(PVA). The characteristics of CdSe hollow spheres were analyzed using X-ray diffraction(XRD), transmission electron microscopy(TEM), UV-vis measurement and PL spectrometer. The characteristics of solvent as water and water-1-propanol mixture in the system played important roles on the controlled synthesis of hollow sphere. Based on the observation of morphological difference of CdSe, the possible mechanism of CdSe hollow sphere formation will be discussed.

전기도금법을 이용한 태양전지용 CdSe 나노로드 제작 (Electrochemical Deposition of CdSe Nanorods for Photovoltaic Cell Applications)

  • 지창욱;김성훈;이재호;김양도
    • 한국재료학회지
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    • 제19권11호
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    • pp.596-600
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    • 2009
  • Electrochemical deposition characteristics of CdSe nanorods were investigated for hybrid solar cell applications. CdSe nanorods were fabricated by electrochemical method in $CdSO_4$ and $H_2SeO_3$ dissolved aqueous solution using an anodic aluminum oxide (AAO) template. Uniformity of CdSe nanorods was dependent on the diameter and the height of holes in AAO. The current density, current mode, bath composition and temperature were controlled to obtain a 1:1 atomic composition of CdSe. CdSe nanorods deposited by direct-current method showed better uniformity compared to those deposited by purse-current and/or purse-reverse current methods due to the bottom-up filling characteristics. $H_2SeO_3$ concentration showed more significant effects on pH of solution and stoichiometry of deposits compared to that of $CdSO_4$. A 1:1 stoichiometry of uniform CdSe nanorods was obtained from 0.25M $CdSO_4-5$ mM $H_2SeO_3$ electrolytes with a direct current of 10 $mA/cm^2$ at room temperature. X-ray diffraction and electron diffraction pattern investigations demonstrate that CdSe nanorods are a uniform cubic CdSe crystal.