• 전기학회논문지
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• 제60권3호
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• pp.552-559
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• 2011

There is a method for offering continuous information by AF track circuits. Magnetic fields are formed by current through rails in the AF track circuit systems. So, the continuous information is received by the magnetic fields on a on-board antenna. Coating materials of spray on rails are researched to decrease defects such as head check, shelling, corrugation, squats and so on in Germany. Currently, a coating method of rail construction is proposed by using the ceramics in Korea. When deciding physical characteristic of the coating material of spray, researches are required about variation of flux density and resistivity by using the coating material of spray. In case that the flux density is much lower than existing value, the information for train control is not transmitted to the on-board antenna. In this paper, inductance on rails is calculated and a model is presented about variation of the magnetic field intensity and resistivity in the AF track circuit. Standard permeability of the coating material of spray is proposed. Also, standard resistivity of the coating material of spray is presented by analyzing short current.

• 전기전자학회논문지
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• 제27권1호
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• pp.78-84
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• 2023

본 논문에서는 컬러 용액을 사용하여 스핀 코팅 방식으로 Building Integrated Photovoltaic(BIPV) 시스템용 전면 컬러 유리를 구현하였다. 컬러 유리 구현을 위해 진주광택 안료와 다양한 용액를 사용하여 컬러 용액에 적합한 용액을 조사하였다. 조사한 용액 중 자외선 광 경화제인 NOA series의 경우 다른 용액보다 우수한 코팅성과 컬러 재현성을 가진 컬러 유리를 구현할 수 있었다. NOA 65 기반의 컬러 용액으로 스핀 코팅하여 구현한 컬러 유리는 가시광선 및 근적외선 파장 대역에서 최대 86%의 높은 투과율을 보였으며 시간에 따른 컬러 유리의 광학적 특성의 변화가 미미하여 BIPV용 컬러 유리 구현을 위한 컬러 용액으로 적합하였다. 스핀 코팅 방식을 활용한 용액 공정 방식은 기존의 물리적 증착 방식이나 나노 입자를 활용한 컬러 유리 제작 공정보다 쉽고 빠르게 컬러 유리를 제작할 수 있어 BIPV용 전면 컬러 유리 제작 공정이 용이해질 것으로 기대된다.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2000년도 특별강연 및 춘계학술발표대회 개요집
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• pp.228-231
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• 2000

Based on the principle of complementary energy an analytical method is developed for determining thermal stress distribution in an thermal barrier coating. This method gives the stress distributions which satisfy the stress-free boundary conditions at the edge. Numerical examples are given in order to verify the method and to investigate the thickness effects of the ZrO$_2$-8wt％Y$_2$O$_3$ top coat on the integrity of thermal barrier coating consisted of IN738LC substrate and MCrAlY bond coat.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2004년도 춘계 학술발표대회 개요집
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• pp.223-225
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• 2004

Based on the principle of complementary energy an analytical method is developed for determining thermal stress distribution in an thermal barrier coating. This method gives the stress distributions which satisfy the stress-free boundary conditions at the edge. Numerical examples are given in order to verify the method and to investigate the thickness effects of the ZrO$_2$-8wt%Y$_2$O$_3$ top coat on the integrity of thermal barrier coating consisted of IN738LC substrate and MCrAlY bond coat.

• 한국인쇄학회지
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• 제10권1호
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• pp.35-54
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• 1992

Direct electrostatic coating method is simple, low cost and environmentally useful method. We are investigated on the coating of carrier transfer polymer layer on the carrier generate inorganic pigment layer using direct electrostatic coating method. The sample was obtained electrostatic deposite layer by fusing and calendering on the copper phthalocyanine. we could be found several polymer thin film shows good bond properties between film and pigment layer.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.416-416
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• 2016

Organic-inorganic metal halide perovskite solar cells have received attention because it has a number of advantages with excellent light harvesting, high carrier mobility, and facile solution processability and also recorded recently power conversion efficiency (PCEs) of over 20%. The major issue on perovskite solar cells have been reached the limit of small area laboratory scale devices produced using fabrication techniques such as spin coating and physical vapor deposition which are incompatible with low-cost and large area fabrication of perovskite solar cells using printing and coating techniques. To solution these problems, we have investigated the feasibility of achieving fully printable perovskite solar cells by the blade-coating technique. The blade-coating fabrication has been widely used to fabricate organic solar cells (OSCs) and is proven to be a simple, environment-friendly, and low-cost method for the solution-processed photovoltaic. Moreover, the film morphology control in the blade-coating method is much easier than the spray coating and roll-to-roll printing; high-quality photoactive layers with controllable thickness can be performed by using a precisely polished blade with low surface roughness and coating gap control between blade and coating substrate[1]. In order to fabricate perovskite devices with good efficiency, one of the main factors in printed electronic processing is the fabrication of thin films with controlled morphology, high surface coverage and minimum pinholes for high performance, printed thin film perovskite solar cells. Charge dissociation efficiency, charge transport and diffusion length of charge species are dependent on the crystallinity of the film [2]. We fabricated the printed perovskite solar cells with large area and flexible by the bar-coating. The morphology of printed film could be closely related with the condition of the bar-coating technique such as coating speed, concentration and amount of solution, drying condition, and suitable film thickness was also studied by using the optical analysis with SEM. Electrical performance of printed devices is gives hysteresis and efficiency distribution.

• Korean Chemical Engineering Research
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• 제45권5호
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• pp.442-447
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• 2007

투명 플라스틱 필름의 표면강도를 향상시키기 위하여 유-무기 혼성 코팅용액을 Sol-Gel 법을 이용하여 합성하였다. 코팅용액은 입자 직경이 12 nm 크기의 무기물인 colloidal silica 용액(Ludox)에 유기물인 GPTMS(glycidoxypropyl trimethoxysilane)를 첨가하여 제조하였다. 그 후에 기재인 PC(polycarbonate) 필름에 담금 코팅(dip-coating)시키고, 상온에서 10분 동안 건조시킨 후, $80^{\circ}C$에서 30분 동안 열 경화시켜 하드 코팅 막을 제조하였다. 이 과정 중 코팅용액의 pH 변화와 GPTMS 첨가량의 변화가 코팅 막의 물성에 미치는 영향을 살펴보았다. pH 4의 산성 조건에서 제조된 코팅용액으로 PC 필름 위에 코팅한 경우는 중성이나 염기성 조건으로 제조된 경우 보다 우수한 연필경도 및 기재와의 부착력을 보였다. 또한 GPTMS의 첨가량이 증가할수록 코팅 막의 연필경도 및 기재와의 부착력이 증가하였다.

• 한국콘텐츠학회논문지
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• 제21권12호
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• pp.918-925
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• 2021

페로브스카이트 태양전지는 기존의 실리콘 태양전지를 대체하는 차세대 태양전지로서, 페로브스카이트 구조를 가진 유-무기 하이브리드 물질을 광 활성층으로 사용하는 태양전지 소자로 고효율, 저가의 용액 공정 및 저온 공정에 유리한 장점들을 가지고 있으며 지난 10년간 빠른 효율 향상을 보여주었다. 이러한 페로브스카이트 태양전지의 상용화 과정에서 대면적 코팅 방법에 대해서 연구개발이 진행되어야 한다. 대면적 페로브스카이트 태양전지 대면적 코팅 방법 중 하나로 슬롯-다이 코팅방법에 대해서 연구 진행하였다. 메니스커스를 이용하여 기판 위를 지나가며 용액을 코팅하는 방법으로 3D printer에 메니스커스를 장착하여 코팅을 할 수 있도록 하였다. 코팅 시 작용하는 변수로는 bed 온도, coating speed, N₂ blowing간격, N₂ blowing 높이, N₂ blowing세기등이 있으며 이를 조절하여 페로브스카이트 흡수층을 제작 진행하였으며, 대면적 소자 제작을 위한 코팅 조건을 최적화 하였다.

• 한국전기전자재료학회논문지
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• 제26권7호
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• pp.550-554
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• 2013

Carbon nanotubes (CNT) / polyvinylidene fluoride (PVDF) piezoelectric composite films for nanogenerator devices were fabricated by spray coating method. When the CNT/PVDF mixture solution passes through the spray nozzle with small diameter by the compressed nitrogen gas, electric charges are generated in the liquid by a triboelectric effect. Then randomly distributed ${\beta}$ phase PVDF film could be re-oriented by the electric field resulting from the accumulated electrical charges, and might be resulted in extremely one-directionally aligned ${\beta}$ phase PVDF film without additional electric field for poling. X-ray diffraction patterns were used to investigate crystal structure of the CNT/PVDF composite films. It was confirmed that they revealed extremely large portion of the ${\beta}$ phase PVDF crystalline in the film. Therefore we could obtain the poled CNT/PVDF piezoelectric composite films by the spray coating method without additional poling process.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.233-233
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• 2006

[ $Y_{2}O_{2}S:Eu$ ], a red phosphor, coated with silica nanoparticles or nanocomposites composed of silica nanoparticles and polymeric materials such as PMMA and PVP was prepared via sol-gel process. Samples were prepared from four different methods coded P1, P2, P3, and P4. P1 includes a conventional sol-gel process and a dip-coating method while P2 has the same procedure with P1 except that nanocomposites containing both silica nanoparticles and polymer prepared by sol-gel process were used as coating materials. In P3 method, phosphors were dispersed in a solution containing silica precursor, i.e., TEOS and then polymerization was performed to coat onto the phosphors surface while P4 followed the same procedure with P3 except that a solution containing both TEOS and organic monomer were used in preparing coating materials. Among various coating methods examined in this study, uniform coating of phosphor could be achieved by using method P4, i.e., phosphor surface coating in a solution containing hydrophobic monomer and TEOS. Furthermore, $Y_{2}O_{2}S:Eu$ red phosphor coated with nanocomposite composed of PMMA matrix and silica nanoparticles exhibited enhanced PL intensity and long-term stability.