• International Journal of CAD/CAM
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• 제3권1_2호
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• pp.111-117
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• 2003

The paper presents an efficient algorithm based on ROAM for visualization of large scale terrain models in real-time. The quality and smoothness of the terrain data visualization within a 3D interactive environment is preserved, while the complexity of the algorithm is kept on a reasonable level. The main contribution of the paper is an introduction of a number of efficient techniques such as implicit coordinates method within the patch array representing ROAM and the viewpoint dependent triangle rendering method for dynamic level of detail (LOD) updates. In addition, the paper presents experimental comparison of a variety of culling techniques, including a newly introduced method: relational position culling. These techniques are incorporated in the visualization software, which allows to achieve more realistic terrain representation and the real-time level of detail reduction.

• 설비공학논문집
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• 제6권3호
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• pp.218-226
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• 1994

Laminar flow and heat transfer in a channel with blockages are obtained numerically in a Reynolds-number range of $100{\leq}Re{\leq}400$. A boundary-fitted curvilinear coordinate system is generated for irregular boundary of the physical region, and solutions of Navier-Stokes equation and energy equation are obtained by finite analytic method in the transformed computational domain. The flow separates in downstream of the blockage and the length of separated-flow region increases with Reynolds number. The heat flux is high on the top of the blockages and increase in the heat transfer occurs where the fluid reattaches the wall. Comparison between computed streamlines and experimental flow-visualization is also presented and discussed.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 1995년도 창립기념학술대회
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• pp.38-43
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• 1995

Effect of visualization as a tool for the education of fluid dynamics is mainly discussed. Visualized images are much more understandable compared to the explanation using equations and texts. Several examples are presented to clarify this statement. Then, the software system for teaching fluid dynamics using the results by the numerical simulation is discussed. Two important issues on what is needed in the system are given. First, such systems should be capable of animating images. Second, such systems should be interactively used by students. Changing parameters, coefficients, equations, etc. themselves and watching the difference are important for them to understand the nature of physics underlying the equations. The teaching system with visualization is no doubt a good tool for introducing fluid dynamics.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2001년도 춘계학술대회 논문집
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• pp.270-275
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• 2001

The characteristics of flow in dividing regions are precise, therefore their classification is very important not only in industry but also in hydrodynamics. By now, many studies of flow in dividing regions have been peformed, but flow characteristics that use visualization In dividing regions have not been studied. The present study of the PIV and the CFD exhibit average velocity distributions, kinetic energy distributions and total pressure distributions etc of the total flow field due to the development of the accurate visualization optical laser and of optical equipment. Also, PIV is accurate with the flows characteristics of the dividing region as continuous analysis is done using input equipment. The study analyzes velocity vector field, turbulence kinetic energy, turbulence viscosity of dividing regions with flow for visualization of the PIV and the CFD measurement in a dividing rectangular ducts.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2002년도 춘계 학술대회논문집
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• pp.158-163
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• 2002

In the present study a 3D data visualization and analysis program with stereoscopic viewing is introduced. The GUI of the program is based on Qt-library, while all the graphic rendering is performed with OpenGL library. The program allocates memory dynamically according to the data size so that the problem size is only limited by the computer's hardware memory. The stereoscopic viewing is realized by carefully-calibrated projection and color-masking of red and blue color for the left and right eye, and the only hardware needed for the stereoscopic visualization of 3D data is a cheap and easily-available red/blue glasses. Further work for addition of more functions and options to the present program will be continued.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2004년도 제22회 춘계학술대회논문집
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• pp.784-788
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• 2004

A visualization study of shock formation of the supersonic jet nozzle using a Shadowgraph Method (SM) was carried out to investigate the effect of the longitudinal variation of coaxial pipe end tip position inside the supersonic nozzle. The experiment was performed for the Mach number range from 1.1 to 1.2 at nozzle exit. The well known shock cell structure was shown with the pipe end located deep inside the nozzle for the studied Mach number. With the pipe end approaches nozzle exit, it was found that the shock cell structure disappeared and turned into complex formation. In order to understand the mechanism of the shock structural change, computational simulation was carried out using the Navier-Stokes solver, FLUENT. Topological sketch was added with an aid of the visualization and the numerical simulation.

• 한국가시화정보학회:학술대회논문집
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• 한국가시화정보학회 2006년도 추계학술대회 논문집
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• pp.149-152
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• 2006

This paper describes the flow visualization around the model of a commercial passenger airplane, Boeing 747-400, which cruises in the transonic speed. The geometry was realized through the reverse engineering based on the photogrammetry. The three-dimensional inviscid steady compressible governing equations are solved in the unstructured grid system under the cruise condition and in a finite volume method. The convective term is processed by the Crank-Nicholson scheme and first order upwind scheme is applied. The lift and drag forces in the wing with engines increase by 1.49% End 3.9%, respectively compared with the wing without engines.

• 한국가시화정보학회:학술대회논문집
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• 한국가시화정보학회 2002년도 추계학술대회 논문집
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• pp.73-76
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• 2002

A one-dimensional fluid model has been established for Raman amplification of a short laser pulse in a plasma by a counter-propagating pump. The laser pulse is amplified with a large gain and also may be compressed by nonlinear three-wave Interactions. The spatiotemporal evolutions of the seed and the pump pulses were visualized for linear and nonlinear regimes, and the transition from regular to chaotic behavior of subsidiary pulses was investigated with variation of pump intensity.

• 인터넷정보학회논문지
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• 제21권3호
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• pp.41-51
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• 2020

EDISON is a web-based platform that provides easy and convenient use of simulation software on high-performance computers. One of the most important roles of a computational science platform, such as EDISON, is to post-process and represent the simulation results data so that the user can easily understand the data. We interviewed EDISON users and collected requirements for post-processing and represent of simulation results, which included i) flexible data representation, ii) supporting various data representation components, and iii) flexible and easy development of view template. In previous studies, it was difficult to develop or contribute data representation components, and the view templates were not able to be shared or recycled. This causes a problem that makes it difficult to create ecosystems for the representation tool development of numerous simulation software. EDISON-VIEW is a framework for post-processing and representing simulation results produced from the EDISON platform. This paper proposes various methods used in the design and development of the EDISON-VIEW framework to solve the above requirements and problems. We have verified its usefulness by applying it to simulation software in various fields such as material, computational fluid dynamics, computational structural dynamics, and computational chemistry.

• 전산구조공학
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• 제3권2호
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• pp.117-128
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• 1990

이 연구는 제한된 용량과 기능의 마이크로컴퓨터를 전제로하여 고급의 postprocessing을 효율적으로 달성할 수 있는 algorithm을 개발하고자 의도되었다. 응력도 및 내력도의 도화, 변형의 animation등과 관련된 기존의 postprocessing방법을 개선하엿으며, 이를 바탕으로 새로운 유한요소해석시스템을 개발하였다. 특히 3차원 구조물의 역학적 거동을 가시화하는 문제를 중점적으로 다루었다.