• Applied Microscopy
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• 제29권3호
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• pp.265-274
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• 1999

DC마그네트론 스퍼터링방법으로 공정조건을 변화시키며 종착된 구리박막의 미세구조를 분석하였다. 폴리이미드위에 두께 50nm의 Cr박막을 증착한 뒤 두께 500 nm 또는 1000nm의 Cu 박막을 아르곤 압력을 5, 50, 100 mtorr로 변화시키며 증착하였으며 박막의 미세구조는 범용 SEM과 고분해능 SEM, TEM을 사용하여 관찰하였다. 스퍼터링 압력이 증가할수록 열린 계면이 더 많이 관찰되었다. 5 mtorr에서 형성된 박막의 표면은 균일하고 치밀한 구조인 반면에 높은 압력에서 증착된 시편에는 많은 미세 균열이 관찰되었다. 50, 100 mtorr에서 증착된 시편은 박막 두께의 영향도 관찰되어 500nm의 경우에 비해 두께가 $1{\mu}m$인 두꺼운 박막에서 더 법고 큰 균열이 발견되며 균열의 수도 증가하였다. 고분해능 SEM과 TEM으로 관찰한 결과 5 mtorr에서 증착된 시편의 특정 미세 형상은 하나의 결정립이며 주상정이 잘발달된 50, 100 mtorr에서 증착된 시편에서는 1개의 주상정 내부에 여러개의 결정립이 존재하였다. 증착압력이 증가할수록 구리박막의 결정립 크기가 감소하였는데 이는 구리원자의 표면 확산이 방해 받았기 때문이다.

• 대한수학회지
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• 제40권4호
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• pp.667-680
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• 2003

The mirror conjecture means originally the deep relation between complex and symplectic geometry in Calabi-Yau manifolds. Recently, this conjecture is posed beyond Calabi-Yau, and even to, open manifolds (e.g. $A_{n}$ singularities and its resolution) is discussed. While if we treat open manifolds, we can't avoid the boundary (in our case, CR manifolds). Therefore we pose the more precise conjecture (mirror symmetry with boundaries). Namely, in mirror symmetry, for boundaries, what kind of structure should correspond\ulcorner For this problem, the $A_{n}$ case is studied.

• 물과 미래
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• 제20권3호
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• pp.219-228
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• 1987

만내 및 입구부에 대한 흐름해석으로 천수방정식이 이용되었으며, 개방경계의 위치를 변화시키며 해석하였다. 만입구로부터의 거리를 변화시키며 설정된 반도형태의 개방경계에 대한 수치해석결과 적절한 개방경계의 위치는 만입구의 폭을 2B라 했을 때 이에 대한 관계로 표현할 수 있고 3B 이상인 경우에서 해는 안정한 상태로 되어 최적의 개방경계위치는 3B가 적절할 것으로 판단되었다. 천수방정식에 대한 수치기법으로는 전형적인 Galerkin 방법에 의한 유한요소법이 적용되었다.

• Structural Engineering and Mechanics
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• 제73권1호
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• pp.75-82
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• 2020

In this study, the problem of torsion of bars with open cross section surrounded by corrugated boundaries is analyzed. An approximate analytical solution is given using perturbation technique. First, the stress analysis for circular open cross-section for arbitrary opening angle is formulated and the problem is analytically solved. Second, the open cross-section with corrugated cross section is analyzed using perturbation method. First order contributions to the stresses and the torques have been added. The results have been exemplified and compared by considering special examples.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1997년도 추계학술대회 논문집
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• pp.202-205
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• 1997

We investigated grain boundary effect for terrestrial applications of solar cell\ulcorner with low cost, large area, and high efficiency. Grain boundaries are known as potential barriers and recombination centers for the photo-generated charge carriers, which make it difficult to achieve a high efficiency cell. To reduce these effects of grain boundaries, we investigated various influencing factors such as thermal treatments, various grid patterns, selective wet etchings for grain boundaries, buried contact metallizations along grain boundaries, and use of metallic thin films. From the various grid patterns we learned that the series resistance of solar cell reduced open circuit voltage and consequently decreased the cell efficiency. This paper describes the effect of various grid patterns and the employment of metallic thin films for a top electrode.

• International Journal of Naval Architecture and Ocean Engineering
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• 제1권2호
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• pp.89-94
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• 2009

The current focus of development in industrial Computational Fluid Dynamics (CFD) is integration of CFD into Computer-Aided product development, geometrical optimisation, robust design and similar. On the other hand, in CFD research aims to extend the boundaries of practical engineering use in "non-traditional" areas. Requirements of computational flexibility and code integration are contradictory: a change of coding paradigm, with object orientation, library components, equation mimicking is proposed as a way forward. This paper describes OpenFOAM, a C++ object oriented library for Computational Continuum Mechanics (CCM) developed by the author. Efficient and flexible implementation of complex physical models is achieved by mimicking the form of partial differential equation in software, with code functionality provided in library form. Open Source deployment and development model allows the user to achieve desired versatility in physical modeling without the sacrifice of complex geometry support and execution efficiency.

• 복식문화연구
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• 제31권6호
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• pp.806-823
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• 2023

The aim of this study was to analyze the design characteristics of Chinese fashion designer Feng Chen Wang and interpret their implicit meaning from a neo-deconstruction perspective. A review of domestic and foreign literature, outlined the develop- ment of deconstruction and neo-deconstruction, with neo-deconstruction's aesthetic features termed 'traditional fusion', 'positive playfulness', 'open communication', and 'multiple inclusiveness'. These features informed an analysis of Feng Chen Wang's fashion design. Four key findings emerged. First, 'traditional fusion' combines traditional Chinese colors, items, handicrafts, and patterns with modern design to break down boundaries between past and modern, tradition and fashion. Second, 'positive playfulness' promotes creativity and fun, using bright colors, exaggerated accessories, and playing withthe composition of traditional clothes to create a positive atmosphere. Third, 'open communication' emphasizes design that combines practicality and creati- vity in response to consumer needs, incorporating the thoughts arising from individual experiences and interest in social phenomena. Fourth, 'multiple inclusiveness' breaks down boundaries of sexuality, hierarchy, and body shape, embracing various ideas of beauty and respecting uniqueness through design that are seen as available to all. Using a neo-deconstruction perspective, Feng Chen Wang provides novel product planning ideas for Chinese fashion brands and reflects the values and meaning of modern design pursued by contemporary Chinese designers.

• 대한지리학회지
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• 제42권5호
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• pp.710-727
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• 2007

본 논문은 한국에서 피시방으로 불리는 인터넷 카페에 의해 생산된 도시경관의 성격과 함의, 그리고 피시방에서 실제와 가상공간 사이에 혹은 인간과 기계 공간 사이에 존재하는 사이보그로서 인간 육체의 활동과 경계에 대한 그들의 영향을 탐구한다. 두 부분으로 구성되어 있는 본 논문은 먼저 전자 건축 공간으로서 피시방의 거리경관을 조사하고 피시방의 도시 전자 공간을 하이퍼텍스트 공간의 의미에서 제시한다. 그런 다음, 피시방에서 인간-기계 혼성체 혹은 사이보그로서 존재하는 인간 육체에 대한 피시방의 영향을 조사한다. 실제와 가상 공간 사이의 혹은 인간과 기계 공간 사이의 제삼 공간, 경계 공간 혹은 혼성 공간으로서 피시방의 패러독스적 사회-공간적 특징은 다음과 같이 설명될 수 있다. 먼저, 피시방에서 사람들은 한편으로는 가상 공간에서는 이동하지만, 다른 한편으로는 실제 공간에서는 정적이라는 점에서 유목적이고 동시에 정착적인 경관이 나타난다. 둘째, 비록 피시방이 열린 공적인 전자공간으로서 역할을 하지만, 남성주의적인 젠더화된 공간을 형성하면서 보이지 않는 사회적 경계를 갖고 있다는 점에서 열린 공간이면서 닫힌 공간이다. 셋째, 피시방에서 인간 육체의 감각적 경계는 전자 네트워크를 통해 확장되지만, 동시에 그것의 사회적 경계는 자기중심적인 상상의 공간을 통해 수축된다. 그리하여 마지막으로, 피시방은 육화되고 젠더화된 경관을 갖고 있는 사회적 공간일 뿐만 아니라, 인간-기계의 결합의 사이보그 경관을 수반하는 비-장소로 특징지을 수 있다.

• 전기전자학회논문지
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• 제25권4호
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• pp.650-663
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• 2021

Subsurface topology estimation is an important factor in the geophysical survey. Electrical impedance tomography is one of the popular methods used for subsurface imaging. The EIT inverse problem is highly nonlinear and ill-posed; therefore, reconstructed conductivity distribution suffers from low spatial resolution. The subsurface region can be approximated as piece-wise separate regions with constant conductivity in each region; therefore, the conductivity estimation problem is transformed to estimate the shape and location of the layer boundary interface. Each layer interface boundary is treated as an open boundary that is described using front points. The subsurface domain contains multi-layers with very complex configurations, and, in such situations, conventional methods such as the modified Newton Raphson method fail to provide the desired solution. Therefore, in this work, we have implemented a 7-layer artificial neural network (ANN) as an inverse problem algorithm to estimate the front points that describe the multi-layer interface boundaries. An ANN model consisting of input, output, and five fully connected hidden layers are trained for interlayer boundary reconstruction using training data that consists of pairs of voltage measurements of the subsurface domain with three-layer configuration and the corresponding front points of interface boundaries. The results from the proposed ANN model are compared with the gravitational search algorithm (GSA) for interlayer boundary estimation, and the results show that ANN is successful in estimating the layer boundaries with good accuracy.

• 전자공학회논문지A
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• 제32A권10호
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• pp.19-24
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• 1995

The majority of problems to which FDTD is being applied involve open structure which require the appropriate scheme to terminate the computational domain. In particular, for the propagation problem of the outgoing waves, a certain type of boundary condition needs to be applied on outer boundaries of the computational domain to generate no reflected waves. In this paper, a new simple technique is presented, which allows the reduced computation time and excellent absorbing characteristics for normal and oblique incident waves on outer boundaries. To illustrate the validity of this method, a numerical calculation for monopole antenna is carried out and the results are compared to measured data. The time-domain properties for circular patch antennas are investicated.