• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2006년도 춘계 학술발표회 논문집
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• pp.239-248
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• 2006

The interaction between ground water and structure is complicated behavior which cannot be easily investigated In the laboratory and monitored in the fields. In this study numerical simulation of the interactive behavior was performed using sophisticated coupled-finite element method. Hydraulic behavior of structure is modeled using solid elements with finite Permeability. Recovery of ground water table in the long-term is considered by controlling hydraulic boundary conditions. The results showed that the interaction effect is significant. Particularly non-symmetry in the lining permeability resulted in highly unbalanced pore water pressure which may cause detrimental effects on inner linings of tunnels acting as drains.

• 한국정밀공학회지
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• 제13권9호
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• pp.84-93
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• 1996

This paper describes the development of new feature positioning method which embedded into the top-down assembly modeling system supporting conceptual design. In this work, the user provides the geometric constraints representing the position and size of features, then the system calculates their proper solution. The use of geometric constraints which are easy to understand intuitively enables the user to represent his design intents about geometric shapes, and enables the system to propagate the changes automatically when some editing occurs. To find the proper solution of given constraints, the Selective Solving Method in which the redundant or conflict equations are detected and discarded is devised. The validity of feature shapes satisfying the constraints can be maintained by this technique, and under or over constrained user-defined constraints can also be estimated. The problems such as getting the initial guess, controlling the multiple solutions, and dealing with objects of rotational symmetry are also resolved. Through this work, the feature based modeling system can support more general and convenient modeling method, and keeps the model being valid during modifying models.

• 한국실내디자인학회논문집
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• 제41호
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• pp.29-35
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• 2003

The purpose of this study is to analyze the architectural manifesto and design works characteristics of Walter Gropius. He was the director of Weimar Bauhaus that one of the advanced artificial movements in the early modern period. The almost of the early modern movements was related to the radical ideology and the manifesto. Especially Bauhaus originated from manifesto of artists teaching group with architect Walter Gropius. Therefore, the category of the study pitch upon Bauhaus architectural manifesto - Bauhaus Manifesto and Programme(1919) - and the representative works of Walter Gropius - Fagus Factory(1911-14), Dessau Bauhaus Building(1925-26), Siedlung Berlin-Siemensstadt(1929-30) and Harvard Graduate Center(1949). The conclusions of the study as per the above mentioned pill pose are the dynamic integration by non-symmetry in cubic form (formal characteristics) and organic continuity by reciprocality in transparent space (spatial characteristics).

• 대한기계학회논문집B
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• 제25권5호
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• pp.697-704
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• 2001

The flow between two concentric cylinders, with the inner one rotating, is studied using numerical simulation. This study considers the identical flow geometry as in the experiments of Wereley and Lueptow[J. Fluid Mech., 364, 1998]. They carried out experiment using PIV to measure the velocity fields in a meridional plane of the annulus in detail. When Taylor number increases over the critical one, the flow instability caused by curved streamlines of the tangential flow induces Taylor vortices in the flow direction. As Taylor number further increases over another critical one, the steady Taylor vortices become unsteady and non-axisymmetrically wavy. The velocity vector fields obtained also show the same flow features found in the experiments of Wereley and Lueptow.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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• pp.455-455
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• 2000

A novel pulse-width-modulated (PWM) function is introduced for precise position measurement in an enclosed signal field. An amplitude modulation was used to light the LEDs for the conventional study. However, the transform properties from the driving signal to the lighting intensities of the LEDs are non-linear, and accurate control of the lighting power was necessary. Therefore, a lighting function independent of these properties is desired. Well-known PWM functions are used to construct the enclosed signal field by simulation, and the precision of the phase detecting system is analyzed. A novel "axial symmetry PWM" function is found to be effective for orthogonal pahse detection.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 추계학술대회 논문집
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• pp.641-645
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• 2002

In case of aluminum-cased battery, The ratio of height and base of square is generally above the ten times, square-shaped and problem of non-axis symmetry. It is typical model to set up the analysis method of finite element. The reliable analysis of finite element method is suggested, which is used to investigate the possibility that multi-stage deep drawing and ironing used currently is replaced by backward impact extrusion favorable in the respect of cost production and productivity. The influence of parameter was analyzed and compared, which was considered to analyze the process of large deformation plasticity such as extrusion. Die and billet was made as the same shape of finite element model. The results of experiment show good forming without the rupture and wrinkles with the optimum velocity 100mm/sec obtained by analysis.

• International Journal of CAD/CAM
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• 제9권1호
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• pp.103-109
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• 2010

Recently, various conformal geometric methods have been presented for non-rigid surface matching and registration. This work proposes to improve the robustness of conformal geometric methods to the boundaries by incorporating the symmetric information of the input surface. We presented two symmetric conformal mapping methods, which are based on solving Riemann-Cauchy equation and curvature flow respectively. Experimental results on geometric data acquired from real life demonstrate that the symmetric conformal mapping is insensitive to the boundary occlusions. The method outperforms all the others in terms of robustness. The method has the potential to be generalized to high genus surfaces using hyperbolic curvature flow.

• 대한기계학회논문집B
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• 제29권1호
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• pp.63-70
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• 2005

The main objective of the present study is to predict characteristics of three dimensional pulstitile flow by location of stenosis in blood vessel with the second order bifurcation. The present study simulates the incompressible non-Newtonian laminar blood flows using a Fluent V. 6.0. The Carreau model is employed as the constitutive equation for blood. The numerical simulation carried out at five cases without and with symmetry or asymmetry stenosis. It is found that the no stenosis and stenosis before first bifurcation do not have influence on flow at second bifurcated blood vessel. However, the stenosis after first biburcation has effect on flow at second bifurcated blood vessel.

• 소성∙가공
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• 제3권3호
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• pp.320-334
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• 1994

A set of full size cold rolled steel sheets has been prestrained in the direction of rolling by uniform tensile elongation of 3% and 6%. Then mid-sized tensile specimens were cut from each of the full size sheets at 30, 45, 60 and 90 degrees to the rolling direction. The mid-sized tensile specimens were then prestrained again by uniform tensile elongation by 1%, 2%, 5%, 10% and 15%. finally, miniature tensile specimens were prepared from each of the mid-sized specimens at every 10 degrees to the specimen axis. From the tensile tests on miniature specimens material's hardening behavior under non-proportional loading has been investigated. There are a number of new observations which has not been known to the authors before current work. One of them is continuous reservation of orthoropic symmetry during tensile elongation of mid-sized specimens. Another is continuous rotations of orthotropy axes. Existing theories seem to fail to explain this observations. A new model is proposed in relation to the rotation of orthotropy axes.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2008년도 춘계학술대회 논문집
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• pp.458-461
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• 2008

We carry out non-steady state finite element simulation of a porthole extrusion process for manufacturing a radiation pipe under isothermal assumption. It is assumed that welding takes place at the moment that the material contacts the plane of symmetry. Welding phenomena are revealed by observing the contacting mechanism of the material passed through the portholes. It is emphasized that mesh density control and intelligent remeshing during welding process govern the solution accuracy and the program applicability. AFDEX 3D is employed.