• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.440-440
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• 2012

The optical characteristics of transparent electrode with various kind of materials and thickness to be used for organic photovoltaic cells were studied by simulation methodology. It demonstrated that the transmittance varies with the kinds of materials, the number of layers and change in the thickness of each layer. In the case of the structure composed of dielectric/Ag/dielectric, optimized transmittance was higher than 90% at 550 nm and the thickness of the Ag layer was ~10nm. Top and bottom dielectric materials can be changed with different refractive index and extinction coefficient. The relation between the optical transmittance of device and transparent electrode with different refractive indices was discussed as well. By processing numerical simulations, an optimized optical transmittance can be obtained by tunning the thickness and materials of transparent electrode.

• 한국재료학회지
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• 제10권8호
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• pp.581-588
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• 2000

Free surface를 가진 레나트-존스 이원계의 가열, 냉각에 따른 상전이를 molecular dynamics simulation을 이용하여 연구하였다. 용매-용질우너자간의 size misfit과 용질우너자의 농도변화에 따른 상전이 거동을 살펴본 결과 size misfit과 용질원자의 농도가 증가함에 따라 가열시 용융시 낮은 온도에서 쉽게 발생하였고, 냉각시 임계냉각속도가 감소하여 결정화는 어려워졌다.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2000년도 추계학술발표강연 및 논문개요집
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• pp.89-89
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• 2000

• Journal of Korean Vacuum Science & Technology
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• 제6권1호
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• pp.22-29
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• 2002

The process of energetic deposition has been simulated by using molecular dynamics (W) simulation and kinetic Monte Carlo (KMC) simulation. The atomistic mechanisms of film growth in energetic deposition are discussed.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 하계학술대회 논문집
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• pp.312-312
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• 2009

본 연구에서는 Thermal evaporator(저항 가열 식 진공 증착법) 장비를 활용하여 ZnS/$Na_3AlF_6$/ZnS/Cu-$0.25\lambda$, ZnS/$CaF_2$/ZnS/Cu-$0.25\lambda$의 다층 박막을 glass 기판위에 증착하였다. 증착 전에 EMP(Essential Macleod Program)을 활용하여 광학적 특성을 simulation하였으며 다층 박막 제작 후 Spectrophotometer를 사용하여 반사율 및 색상을 CIE $L^*a^*b^*$ 좌표에 표시하여 고 굴절 물질에 따른 광학적 특성을 EMP simulation과 비교하였다. AES depth profile을 분석하여 막의 두께 및 층간 확산여부에 관하여 관측 하였다. 저굴절 물질을 Na3AlF6로 사용하였을 경우 simulation과 결과 값 모en purple 계통의 색상을 나타냈으며 CaF2를 사용하였을 경우 simulation은 purple 계통의 색상, 결과값은 red-yellow 계통의 색상으로 나타났다.

• Agricultural and Biosystems Engineering
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• 제2권1호
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• pp.7-14
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• 2001

A rice mill plant with a capacity of 3 t/h was constructed with automated facilities at Chonnam National University. A simulation model was developed with SLAMSYSTEM for evaluation and improving the rice mill process. The developed model was validated in the views of hulling efficiency, milling efficiency, milled rice recovery, other materials produced, at bottlenecks in the processes. The results of hulling efficiency, milling efficiency, milled rice recovery in the simulation were, respectively, 81.1%, 89,5%, and 73.1%, while those of the actual mill plant were 81.5%, 90.2%, and 73.5%. The simulation results including the rates of other materials(chaff, bran, broken rice, stone, etc) produced in the processes were almost similar with those of the actual process. In the simulation the bottlenecks were found out in the process for separating brown rice and sorting colored rice. These phenomena also appeared in the actual process. It needed to increase the hourly capacities of the brown rice separator and the rice color sorter. As the developed model could well express the automated rice mill plant, it could be used for designing and improving rice mill plants.

• 한국세라믹학회지
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• 제53권3호
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• pp.288-294
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• 2016

The densification process during liquid-phase sintering was simulated by Monte Carlo simulation. The Potts model, which had been applied to coarsening during liquid-phase sintering, was modified to include vapor particles. The results of two- and threedimensional simulations showed a temporal decrease in porosity, in other words, densification, and an increase in the average size of pores. The results also showed growth of solid grains and the effect of wetting angle on microstructure.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2003년도 춘계학술발표대회 논문집
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• pp.5-9
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• 2003

Stress and deflection of Active Fiber Composite(AFC) embedded and/or attached composite structures are numerically investigated at the constituent level by the Direct Numerical Simulation(DNS). The DNS approach which models and simulates the fiber and matrix directly using 3D finite elements need to be solved by efficient way. To handle this large scale problem, parallel program for solving piezoelectric behavior was developed and run on the parallel computing environment. Also, the stress result from DNS approach is compared with that from uniform field model.

• Fibers and Polymers
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• 제4권1호
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• pp.15-19
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• 2003

The self-assembly of asymmetric ABC triblock copolymers in the ordered structure is investigated using an isothermal-isobaric molecular dynamics simulation. Unlike symmetric A BC triblock copolymers, more fascinating mophologies are observed in asymmetric ones because of a larger difference of incompatibility between the components. Various modes of self-assembly in assymmetric ABC triblock copolymers are also observed depending on the block composition. When the composition of block A Is changed from 0.125: to 0.25 at the same $f_B$ : 0.25, the morphological transition from the “cylinder in cylinder” to “cylinders at cylinder” structure is observed in the simulation. In the case of ABC triblocks with $f_B$=0.5, a lamellar-type structure is changed to a cylinder-type structure with increasing the length of block A. When the midblock length increases further to $f_B$=0.625, the “spheres on cylinder” structure is observed in both the $A_{10}$$B_{50}$$C_{20}$ and $A_{20}$$B_{50}$$C_{10}$ triblocks. From these results, the phase diagram of ABC triblock copolymers can be constructed.

• 한국결정성장학회지
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• 제15권4호
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• pp.162-167
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• 2005

건조공정 중인 다공성 물질의 물성은 재료의 비균질성 즉 전위, 입자, 입계, 균열, 기공과 같은 미시적인 결함인자들의 영향을 받는다. 따라서 다공성 물질의 건조공정을 전산 시뮬레이션하기 위해서는 원자 스케일 해석을 통한 미시적 물성을 알아야 한다. 본 연구에서는 분자동역학 시뮬레이션을 이용하여 원자 모델을 구성하고 원자 상호간 거동을 예측하여 재료의 미시적 물성을 계산하였다. 이렇게 구한 탄성계수, 열팽창계수, 체적 열용량은 실험 및 이론에 기초한 결과들과 비교하여 검증하였다.