• Applied Microscopy
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• v.29 no.3
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• pp.265-274
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• 1999

The microstructure of Cu thin films in various deposition conditions was characterized. Cr films (50 nm thick) and Cu films (500 or 1000 nm thick) were deposited on polyimide films by DC magnetron sputtering. The Ar pressure during Cu deposition was controlled to 5, 50 and 100 mtorr. The microstructure was characterized using conventional and high resolution SEM and TEM. As sputtering pressure increases, open boundaries are observed more frequently. The Cu film deposited at 5 mtorr has a dense and uniform structure, while low-density regions or open boundaries between columns exist in the film deposited at higher pressure. As the film grows thicker, open boundaries are wider and the density of open boundaries are higher. The comparison between SEM and TEM show that the small features shown in high resolution SEM are grains. High resolution SEM is very effective to characterize the microstructure of the thin films. One column in the films deposited at 50 and 100 mtorr consists of several grains, which are smaller than those deposited at 5 mtorr.

• Journal of the Korean Mathematical Society
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• v.40 no.4
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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.

• Water for future
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• v.20 no.3
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• pp.219-228
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• 1987

Shallow water equations were applied to the flow in and through the opening to a coastal bay with different open boundary conditions. The open boundaries, shaped like a semi-circle, have various radii. the open boundaries therefore are defined in terms of radius given by multiple of the opening width, 2B. It was found from numerical experiments that for adequate results proper radius of the boundary is 3B or greater and that for radius greater than 3B the solutions become stable. For the solution of the shallow water equations a typical Galerkin's finite element method was used.

• Structural Engineering and Mechanics
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• v.73 no.1
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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.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1997.11a
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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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• v.1 no.2
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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.

• The Research Journal of the Costume Culture
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• v.31 no.6
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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.

• Journal of the Korean Geographical Society
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• v.42 no.5
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• pp.710-727
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• 2007

This paper suggests an inquiry into the characteristics and implications of urbanscapes produced by Internet cafes, widely called PC Bangs in Korea, and their effects on the motions and boundaries of human bodies as cyborgs which exist in between actual and virtual spaces or between human and machine spaces in PC Bangs. The paper, which is organised into two main sections, first investigates the streetscapes of PC Bangs as electronic architectural spaces and suggests the urban electronic space of PC Bangs in terms of hypertext space. Then, it looks at the effects of PC Bangs on human bodies which exist as human-machine hybrids or cyborgs in PC Bangs. The paradoxical socio-spatial characteristics of PC Bangs as third, liminal or hybrid spaces between actual and virtual spaces or between human and machine spaces can be explained as follows. Firstly, there appear both nomadic and sedentary landscapes in that people in PC Bangs move in virtual spaces on the one hand, and are static in actual spaces on the other hand. Secondly, both open and closed spaces are shaped in that although PC Bangs act as open or public electronic spaces, they involve invisible social boundaries, forming the gendered space of masculinism. Thirdly, the boundaries of the human body are extended and are shrunk at the same time in that while the sensory boundaries of the body in PC Bangs are extended through electronic networks, its social boundaries are shrunk through the imaginary space of solipsism. Thus and finally, PC Bangs can be characterised not only as social spaces entailing embodied and gendered landscapes, but also as non-places involving the cyborg landscapes of human-machine connections.

• Journal of IKEEE
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• v.25 no.4
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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.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.32A no.10
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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.