• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2006년 제4회 한국유체공학학술대회 논문집
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• pp.109-112
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• 2006

Recently, when we conducted meteorological observations, complicated land or building around weather station has influenced on the wind distribution. So, we should understand the effect of geometry to get more accurate data. In this study, we analyze the ideal geometry whose shape is hemisphere using CFD method. And then we apply this method to real geometry. And we investigate the velocity at the location of weather station. As the results, we could find out an important relationship between geometry and flow field.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 추계학술대회논문집A
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• pp.556-561
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• 2001

In order to investigate the vibration characteristics of fluid-structure interaction problem, we modeled two rectangular identical plates coupled with bounded fluid. The fixed boundary condition along the plate edges and an ideal fluid were assumed. An experimental modal analysis in order to extract the modal parameters of the system was performed. Finite element analysis was performed using ANSYS to verify modal parameters and analytic results were compared with experimental results. As a result, comparison of experiment and FEM showed good agreement and the transverse vibration modes, in-phase and out of-phase, were observed alternately in the fluid-coupled system. The effect of distance between two rectangular plates on the fluid-coupled natural frequency was investigated.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1997년도 추계학술대회 논문집
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• pp.668-671
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• 1997

In order to investigate the vibration characteristics of fluid-structure interaction problem, we modeled two identical rectangular plates coupled with bounded fluid. The fixed boundary condition along the plate edges and an ideal fluid were assumed. A commercial computer code, ANSYS was used to perform finite element analysis and FEM solutions were compared with the experimental results to modify the finite element model. As a result, comparison of FEM and experiment showed good agreement, and the transverse vibration modes, in-phase and out of-phase. were observed alternately in the tluid-coupled system. The effects of distance between two rectangular plates and width to length ratio on the fluid-coupled natural frequency were investigated. And it was found that the ormalized natural frequency of the fluid-coupled system monotonically increased with an increase in the number of modes.

• 한국군사과학기술학회지
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• 제13권6호
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• pp.1013-1018
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• 2010

This paper presents a numerical evaluation of the launch dynamics and thermo-fluid phenomena for gas generator launch eject system. The existing gas dynamic model for launching eject body used ideal gas and adiabatic assumption with empirical energy loss model. In present study, a turbulent Navier-Stokes solver with CHIMERA mesh is employed to predict the detail unsteady thermo-fluid dynamics for the launched body. The calculation results show that proper grid number is necessary for good agreement with experimental data. The important effects for accurate prediction are a gap distance and thermal boundary condition on the wall. The computational results show good agreement with experiment data.

• 한국해양공학회지
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• 제14권2호
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• pp.28-35
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• 2000

In this paper a complicated structural behavior in collision and its effect of energy transmission to the collision bulkhead was examined through a methodology of the numerical simulation to obtain a ideal bow construction and a location of collision bulkhead against heat on collision. At present the bow structure is normally designed in consideration of its specific structural arrangement and internal and external loads in these areas such as hydrostatic and dynamic pressure wave impact and bottom slamming in accordance with the Classification rules and the specific location of collision bulkhead by SOLAS requirement. By these studies the behavior of the bow collapse due to collision was synthetically evaluated for the different size of tankers and its operational speed limits and by the results of these simulation it provides the optimal design concept for the bow construction to prevent the subsequent plastic deformation onto or near to the collision bulkhead boundary and to determine the rational location of collision bulkhead.

• 한국항만학회지
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• 제14권2호
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• pp.219-231
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• 2000

In this paper a complicated structural behavior in collision and its effects of energy translation to the collision bulkhead was examined through a methodology of the numerical simulation to obtain a ideal bow construction and a location of collision bulkhead against head on collision. In the present the bow structure is normally designed in consideration of its specific structural arrangements and internal and external loads in these area such as hydrostatic and dynamic pressure, wave impact and bottom slamming in accordance with the Classification rules, and the specific location of collision bulkhead by SOLAS requirement. By these studies the behavior of the bow collapse due to collision was synthetically evaluated for the different size of tankers and its operational speed limits, and by the results of these simulation it provides the optimal design concept for the bow construction to prevent the subsequent plastic deformation onto or near to the collision bulkhead boundary and to determine the rational location of collision bulkhead.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 추계학술대회 논문집 학회본부
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• pp.305-307
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• 1994

In this paper, the desist and the implementation of a robust adaptive controller for trajectory tracking control of the robot manipulator is presented. The proposed control scheme ensures that without any prior knowledge of the robot manipulator parameters, tracking errors are converged to some boundary in the presence of a state-dependent input disturbances as well as the ideal case. The 3 DOF robot manipulator including actuator dynamics is used for the implementation of the proposed control scheme. The experimental results show that the proposed control scheme is valid for trajectory tracking control of the robot manipulator.

• 한국수자원학회논문집
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• 제34권2호
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• pp.187-195
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• 2001

본 연구에서는 TVD기법을 이용한 천수방정식의 수치모형을 개발하였다. 본 모형은 시간과 공간에서 2차 정확도를 가지며 불연속면에서 수치진동을 억제할 수 있다. 풍상차분기법에 근거한 TVD기법은 Riemann 해의 계산이 수반되어야 하며, 여기서는 HLLC기법이 사용되었다. 개발된 모형의 적용성과 정확성을 검증하기 위해 단순화된 하도에서 댐 붕괴파와 포물형 수조에서의 흐름의 오르내림을 모의하였다. 수치해는 해석해와 잘 일치하였다.

• 영어영문학
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• 제57권6호
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• pp.1089-1109
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• 2011

In an attempt to demonstrate in context of Nietzsche's "overman" (ubermensch) and Heidegger's "Being-in-the-World" (Dasein) the collective human efforts to overcome humanism in crisis, I will provide the ground for the poetics of overcoming, the ground which are based upon the double movements of transhumanism and transnationalism. For this purpose, I will turn to the theories of two distinctive poets who reveal and disreveal their truths about the subjecthood or the subjectivity in terms of overcoming: Christopher Dewdney for posthuman transhumanity and Dionisio D. Martinez for transnational cultural contamination Transhumanism represented by Christopher Dewdney manifests an interfusion of outside and inside, thereby collapsing the boundary between the mind and the world, and provides a breakthrough from the limitedly defined mind to the transhuman perspective of overcoming by using terminalogy and techniques from science and technology. The emerging transhumanism reflects the growing interdependence between humans and bio technologies, and suggests a potential improvement of human beings. The main argument of transhumanism is that we humans can and should continue to develop in all possible directions, by overcoming our human limitations by shedding the body and having the disembodied consciousness which will liberate our mind. Kwame Anthony Appiah's "cultural contamination" is another form of overcoming as well as a way to otherness, a counter-ideal of cultural purity which sustains authentic culture, reversing the traditional binary opposition between enriching authenticity and threatening hybridization. Dionisio Martinez's poetry sublimates the negative side of Appiah's concept of contamination, by redeeming the value of the Appiah's list of the ideal of contamination such as hybridity, impurity, intermingling, the transformation that comes of new and unexpected combinations of human beings, a bit of this and a bit of that is how newness enters the world. When a poetic subject is doubly exiled and doubly homeless away from his/her native homeland and home of native language, one has no more identification with the authentic culture of both home and away, but rather anticipates a new identity as a transnational subject to cross the bridge beyond cultural authenticity and to enter into the field of cultural contamination.

• 대한조선학회논문집
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• 제37권1호
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• pp.67-81
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• 2000

본 연구에서는 2차원 비선형 방사문제에 대한 정확하고 효과적인 수치기법을 개발하였다. 물체운동에 의해서 생성되는 비선형파계는 이상유체라는 가정에 의하여 기술되고, 라프라스 방정식은 고차경계요소법과 GMRES(Generalized Minimal RESidual) 알고리즘을 이용하여 신속하고 효율적인 풀이가 가능하도록 하였다. 자유표면과 물체면의 교차점에서 발생하는 교차선문제는 불연속 요소를 이용하여 원활하게 해결하였다. 자유표면의 비선형운동을 기술하기 위해서 음해적 사다리꼴 법칙(implicit trapezoidal rule)을 사용하여 시적분하였다. 물체에 의해서 발생한 비선형파가 수직 하류면에서 반사하는 것을 줄이기 위하여 하류면에 수치감쇠항을 도입하였다. 수치계산 결과로부터 본 시적분법 및 수치방사조건이 비선형 방사문제에 매우 적합함을 확인하였다. 시적분 과정에서 자유표면의 격자점들을 재배치함으로써 수치해법의 효율성을 배가하였으며, 교차점근처의 유동 또한 정확하게 기술하였다. 가속도 포텐셜(acceleration potential) 기법을 이용하여 정확하고 안정하게 비선형 방사력을 구하였다. 본 수치계산결과는 다른 수치계산 및 실험결과와 비교하여 볼 때, 좋은 일치를 보인다.