• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 추계학술대회 논문집 Vol.16
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• pp.571-574
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• 2003

The thin films fabricated by using the layer-by-layer sputtering was compared with the thin film fabricated by using the evaporation method. Re-evaporation in the form of Bi atoms or $Bi_2O_3$ molecules easily bring out the deficiency of Bi atoms in thin film due to the long sputtering time of the layer-by-layer deposition. On the other hand, the respective atom numbers corresponding to BiSrCaCuO phase is concurrently supplied on the film surface in the evaporation deposition process and leads to BiSrCaCuO phase formation. Also, it is cofirmed that by optimizing the deposition condition, each single phase of the Bi2201 phase and the Bi2212 phase can be fabricated, the sticking coefficient of Bi element is clearly related to the changing of substrate temperature and the formation of the Bi2212 phase.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 춘계학술대회 논문집
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• pp.593-594
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• 2006

A novel thermal transfer method was developed to form the phosphor screen for VPT(Video Phone Tube). This method have advantages of simple process, clean environment, saving raw material and running-cost comparison of electrodeposition, spin coating of conventional methods. But now applying phosphor screen for thermal transfer method has been formed three layers (phosphor layer, ITO layer and thermal adhesive layer) on the PET film as substrate. This is complex process, run to waste of raw-material and require of high cost. Also ITO paste at present has been imported from Japan. To improve these problems, we have manufactured phosphor screen formed by two layers (phosphor layer and ITO layer). We have developed ITO paste that had both conductive and excellent thermal transfer abilities, made it of domestic raw-material.

• Wind and Structures
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• 제5권2_3_4호
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• pp.209-226
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• 2002

When predicting unsteady flow and pressure fields around a structure in a turbulent boundary layer by Large Eddy Simulation (LES), velocity fluctuations of turbulence (inflow turbulence), which reproduce statistical characteristics of the turbulent boundary layer, must be given at the inflow boundary. However, research has just started on development of a method for generating inflow turbulence that satisfies the prescribed turbulence statistics, and many issues still remain to be resolved. In our previous study, we proposed a method for generating inflow turbulence and confirmed its applicability by LES of an isotropic turbulence. In this study, the generation method was applied to a turbulent boundary layer developed over a flat plate, and the reproducibility of turbulence statistics predicted by LES computation was examined. Statistical characteristics of a turbulent boundary layer developed over a flat plate were investigated by a wind tunnel test for modeling the cross-spectral density matrix for use as targets of inflow turbulence generation for LES computation. Furthermore, we investigated how the degree of correspondence of the cross-spectral density matrix of the generated inflow turbulence with the target cross-spectral density matrix estimated by the wind tunnel test influenced the LES results for the turbulent boundary layer. The results of this study confirmed that the reproduction of cross-spectra of the normal components of the inflow turbulence generation is very important in reproducing power spectra, spatial correlation and turbulence statistics of wind velocity in LES.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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• pp.503-504
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• 2007

$Bi_2Sr_2Ca_{n-1}Cu_nO_x$(n=0, 1, 2)superconducting thin films have been fabricated by atomic layer-by-layer deposition at an ultra low growth rate using IBS(Ion Beam Sputtering) method. During the deposition, 90 mol% ozone gas of typical pressure of $1{\sim}9{\times}10^{-5}$ Torr are supplied with ultraviolet light irradiation for oxidation. XRD and RHEED investigations reveal out that a buffer layer with some different compositions is formed at the early deposition stage of less than 10 units cell and then Bi-2201 oriented along the c-axis is grown.

• Computers and Concrete
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• 제31권1호
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• pp.9-21
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• 2023

The published studies usually used analytical method, numerical methods or experimental method to determine the stress-strain state and displacement of the single-layer or multi-layer curved shell types, but with a small scale model. However, a full scale multi-layer doubly curved concrete shell roof model should be researched. This paper presents the results of the experiment and simulation analysis involving stress-strain state, sliding between layers, the formation and development of the full scale double-layer doubly curved concrete shell roof when this shell begins to crack. The results of the this study have constructed the load-sliding strain relationship; strain diagram; stress diagram in the shell layers; the N_x, N_y membrane force diagram and deflection of shell. Thisresults by experimental method on a full scale model of concrete have clarified the working of multi-layer doubly curved concrete shell roof. The experimental and simulation results are compared with each other and compared with the Sap2000 software.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권2호
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• pp.1395-1398
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• 2007

MgO thin films were deposited by e-beam evaporator using the 2-step method for alternate current plasma display panels (AC-PDPs). Glancing angle deposition (GLAD) method was employed to produce various surface geometry of the thin film; the bottom layer was deposited on a substrate by normal e-beam evaporation method and the top layer was deposited on bottom layer with $85^{\circ}$ by GLAD method. Results show that firing and sustain voltages improved as the sharpness of surface and isolated columnar structures increases, respectively.

• 한국공간정보시스템학회:학술대회논문집
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• 한국공간정보시스템학회 2004년도 춘계 학술발표회 논문집 제1권1호(통권1호)
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• pp.83-88
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• 2004

First author proposed a proportioning method for member sections of a single layer reticulated dome subjected to uniform and non-uniform load without any geometrical initial imperfection, and discussed the validity and effectiveness of the method which was based on linear buckling stress and a knock down factor. However, buckling of a single layer reticulated dome is strongly affected by initial imperfection. It is well known that geometrical initial imperfections reduce the nonlinear buckling capacity of a single layer raticulated dome. Thus, structural engineers may be recommended to reflect the effects of geometrical initial imperfections in proportioning member sections. In this paper, firstly, the presented proportioning method by first author is applied to dome without consideration of any imperfections and the thickness and diameter of each member are determined. Secondly, the load bearing capacities of the proportioned domes are checked with the imperfection, by the inelastic buckling analysis.

• 멤브레인
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• 제25권6호
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• pp.538-546
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• 2015

폴리설폰막 위에 친수성 고분자를 Layer-by-Layer법으로 코팅하여 복합막을 제조하였다. FE-SEM 분석을 통하여 복합막 표면과 기공 내 코팅층을 확인하였다. 또한 100 ppm NaCl 용액에 대한 복합막의 투과성능 평가를 실시하였다. 복합막 제조를 위한 코팅 고분자는 PVSA, PEI, PAA, PSSA, PSSA_MA를 사용하였다. 폴리설폰막 표면에 8,000 ppm PAA (이온세기 0.35) 수용액을 3분 동안 코팅한 뒤 10,000 ppm PEI 수용액을 4분 동안 코팅하였다. 그 결과 PAA-PEI 복합막의 투과도는 101 LMH, 제거율은 66.7%로 가장 좋은 투과성능을 나타내었다. PAA-PEI 복합막의 투과성능은 도레이케미칼의 NE 4040-70 (투과도 = 30 LMH, 염 배제율 = 40~70%) 제품과 유사한 성능을 보여주는 우수한 투과 특성을 나타내었다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.310.2-310.2
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• 2013

For enhancement of dye-sensitized solar cell performance, TiO2 blocking layer has been used to prevent recombination between electron and hole at the conducting oxide and electrolyte interface. In solid state dye-sensitized solar cells, it is necessary to fabricate pin-hole free TiO2 blocking layer. In this work, we deposited the TiO2 blocking layer on conducting oxide by atomic layer deposition and compared the efficiency. To compare the efficiency, we fabricate solid state dye-sensitized solar cell with using CuSCN as hole transport material. We see the efficiency improve with 40nm TiO2 blocking layer and the TiO2 blocking layer morphology was characterized by SEM. Also, we used this blocking layer in TiO2/Sb2S3/ CuSCN solar cell.

• Journal of Pharmaceutical Investigation
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• 제37권1호
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• pp.7-13
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• 2007

To produce stable polymer coating layer using the interaction between metal stent and polymer layer, Ahx-HSAB was synthesized by coupling 6-aminoheanoic acid (Ahx) with N-Hydroxy succinimidyl 4-azidobenzonate (HSAB) containing photo reactive group. Then, Ahx-HSAB was applied to self·assembled monolayer (SAM) on $TiO_2$-coated surface, since one end of Ahx-HSAB was carboxyl acid which was known to be able to interact with $TiO_2$ surface. That SAM layer was incubated in 1% polycaprolacton (PCL) solution and photoreacted by ultraviolet light (254 nm) to produce the chemical bond between SAM and polymer layer, followed by PCL polymer coating ({\sim}5\;{\mu}m$) by the method of spray coating. The surface change was investigated by measuring of contact angle of the surface. The contact angle values of stainless steel (SS) surface, $TiO_2$-coated surface, SAM layer by Ahx-HSAB, photoreacted surface with PCL and PCL layer by spray coating were 70.48${\pm}$1.89, 38.57${\pm}$3.31, 60.14${\pm}$2.21, 54.91${\pm}$2.70 and 56.47${\pm}$2.12, respectively. The stability of polymer layers was tested by incubation of PCL-coated plates in 0.1M PBS buffer (pH 7.4, 0.05%, Tween 80) with vigorous shaking (200 rpm). While the poiymer layer prepared by these processes showed the intact surface morphology over 3 days, the polymer layers prepared by spray coating of PCL onto SS plate (control 1) and $TiO_2$-coated SS plate (control 2) were Peeled off in 3 days. Thus, the polymer coating method using SAM and photoreaction seems to be a effective method to obtain the stable polymer layer onto SS surface.