• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.233-233
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• 2010

It is important to form the n+ emitter layer for generating electric potential collecting EHP(Electron-Hole Pair). In this paper the formation on the n+ emitter layer of silicon wafer has been made with respect to uniformity of shallow diffusion from a liquid source. The starting material was crystalline silicon wafers of resistivity $0.5{\sim}3\{Omega}{\cdot}cm$, p-type, thickness $200{\mu}m$, direction[100]. The formation of n+ emitter layer from the liquid $POCl_3$ source was carried out for $890^{\circ}C$ in an ambient of $N_2:O_2$::10:1 by volume. And than each conditions are pre-deposition and drive-in time. It has been made uniformity of at least. so, the average of sheet resistance was about 0.12%. In this study, sheet resistance was measured by 4-point prove.

• Korean Chemical Engineering Research
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• v.50 no.1
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• pp.61-65
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• 2012

The onset of convection in a mushy layer is analyzed by using linear stability theory in time-dependent solidification of a binary melt. A simplified model of a near-eutectic mush, in which the mush is assumed to be a porous block, is used and the propagation theory is applied to determine the critical conditions for the onset of convection. The present critical Rayleigh number is higher than the existing experimental result and also theoretical results obtained by considering the mushy layer with an overlying liquid layer. The constant pressure (permeable) condition applied on the mush-liquid interface produces a lower critical Rayleigh number, which is closer to the experimental results of aqueous ammonium chloride solution, compared with the impermeable condition.

• Transactions of the Korean hydrogen and new energy society
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• v.16 no.3
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• pp.284-289
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• 2005

Thermal analysis of cryogenic-capable vessels with insulations have been carried out to store liquid hydrogen($LH_2$). The combined insulations of MLI(Multi-Layer Insulation) and VCS(Vapor-Cooled Shield) under high vacuum are considered in the analysis for various volumes of vessels. Vapor-Cooled Shields(VCS) are installed at cylinder wall as well as disc side of the $LH_2$ vessels. The results indicate that optimal distribution of boiloff vapor from $LH_2$ vessel into two sides of VCS exists based on the evaporation loss. As the volume of $LH_2$ vessel is increased, mass flow rate of boiloff is increased while the evaporation loss per unit volume is decreased.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.788-791
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• 2006

The ion adsorption on an aligning layer deposited onto a conductive electrode in a liquid crystal (LC) cell has been shown to depend strongly on the dielectric constants of the layer and its thickness d. Calculations made in the framework of the three-layer electrostatic theory showed that, depending on those and other intrinsic parameter of the problems, it is possible to observe either ion attraction or repulsion at the aligning surface. Tentative measurements of the ion adsorption dynamics on the aligning layers with various d qualitatively agree with the theory. The results obtained allow the memory effect in LCs and the sticking effect in LC displays (LCDs) to be controlled effectively.

• 정보저장시스템학회:학술대회논문집
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• 2005.10a
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• pp.151-152
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• 2005

Blu-ray 디스크에서는 NA=0.85 의 높은 개구수를 채용함으로써 디스크 보호층의 두께 변동에 따른 구면수차 발생량이 매우 커지는 문제가 발생하게 된다. 따라서 디스크 두께 공차 $3{\mu}m$에서 Blu-ray 시스템의 수차 발생 허용수준을 초과한다. 그리고 Multi-layer 디스크의 경우 각 층의 간격이 $25{\mu}m$ 정도의 간격을 두고 배치되어 있어 기록층 사이에서 발생하는 구면수차의 보정이 필요하며, 종래의 기술은 보상범위가 $3{\mu}m$로 한정되어 사용이 불가능하며 또한 대물렌즈 조립공차가 엄격히 관리되어야 하는 문제점을 안고 있었다. 본 연구에서는 액정렌즈에 의한 구면수차 보정으로 이러한 문제점들을 해결하고자 하였다. 액정렌즈는 오목렌즈 액정소자와 볼록렌즈 액정소자로 구성되며 픽업 광학계 내에 조합하여 설계함으로써 Multi-layer 디스크의 두께 변동에 따라 발생하는 구면수차를 보정하고 대물렌즈 조립공차 문제를 해결할 수 있다.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07a
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• pp.411-414
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• 2005

We have developed a transflective liquid crystal display (LCD) with a single cell gap and a low twisted nematic (LTN) mode in combination with a self-integrated retardation layer. The retardation layer was made of UV curable liquid crystalline material in one step of photo masking process and has both the homeotropic and the planar parts. The proposed transflective configuration has advantages in a simple fabrication process, and the possibility for a single driving scheme due to the similarity between the transmittance and the reflectance.

• Journal of the Korean Chemical Society
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• v.8 no.4
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• pp.183-187
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• 1964

The excess molar surface entropies of each surface layers are calculated applying the modified significant structure theory of liquid. The calculated excess molar surface entropy for the first top surface layer is slightly greater than the entropy of surface formation of ideal molecules,$^5$ the latter is equal to Rln2. The excess entropy for the second surface layer is small and that for the third layer is negligible at low temperatures. The surface tensions of argon, nitrogen, methane, benzene and halogens are calculated applying the modified significant structure theory of liquid.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.491-496
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• 2004

The oscillation of the fluid caused by external forces is called sloshing, which occurs in moving vehicles with contained liquid masses, such as aircraft. cars and liquid rocket and so on. This sloshing effect could be a severe problem in vehicle stability and control. So, various baffles are used in order to reduce the sloshing. The Lagrangian, Eulerian and ALE numerical method is widely used on the analysis of sloshing presently. But, these numerical methods are needed so many CPU time. In this study, for the reduction of the sloshing analysis time, me multi.layer perceptron artificial neural network is introduced and analysis results are presented.

• Journal of the Korean Chemical Society
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• v.57 no.3
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• pp.370-376
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• 2013

A back propagation artificial neural network model with one hidden layer is established to correlate the liquid-liquid equilibrium data of hydrocarbon-water systems. The model has four inputs and two outputs. The network is systematically trained with 48 data points in the range of 283.15 to 405.37K. Statistical analyses show that the optimised neural network model can yield excellent agreement with experimental data(the average absolute deviations equal to 0.037% and 0.0012% for the correlated mole fractions of hydrocarbon in two coexisting liquid phases respectively). The comparison in terms of average absolute deviation between the correlated mole fractions for each binary system and literature results indicates that the artificial neural network model gives far better results. This study also shows that artificial neural network model could be developed for the phase equilibria for a family of hydrocarbon-water binaries.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.348-351
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• 2008

We suggest a viewing angle control mode of liquid crystal display(LCD) with additive thermal controllable optical layer [TCOL], which composed of homeotropically or homogenously well aligned LC layer and patterned hating lines on a substrate. In this system, LCD modes with wide viewing angle characteristics can be used as a main panel.