• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2003년도 The Fifth Asian Computational Fluid Dynamics Conference
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• pp.86-87
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• 2003

Unstructured grid system is suitable for flows of complex geometries. For problems with moving boundary walls, the grid system must be changed and deformed with time if we use a body fitted grid system. In this paper, a new moving-grid finite-volume method on unstructured grid system is proposed and developed for unsteady compressible flows with shock waves. To assure geometric conservation laws on moving grid system, a control volume on the space-time unified domain is adopted for estimating numerical flux. The method is described and applied for two-dimensional flows.

• 한국군사과학기술학회지
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• 제10권2호
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• pp.47-52
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• 2007

Missile staging and airframe separation simulation were performed by using a numerical technique for simulating the dynamics of multiple moving bodies. A 6DOF model is fully integrated into the CFD solution procedure to determine the body dynamics. Chimera grid technique offered efficient CFD simulation of multiple moving bodies. Through this simulation the safety of deployed staging and airframe separation mechanism was verified.

• 대한안전경영과학회지
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• 제23권3호
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• pp.89-96
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• 2021

This study analyzed the physical changes in 119 paramedics transporting equipment at the emergency site and performing post-cardiopulmonary resuscitation through experiments. First, the average heart rate increased by about 25 times comparing CPR was performed without physical load and with personal protective equipment after moving equipment. In the third quartile, it increased to about 27 times. Second, when CPR was performed without physical load, and CPR was performed after moving the equipment with personal protective equipment, both the body temperature was raised and the rising body temperature was measured within normal body temperature. Third, the change in respiration rate increased by 7 times on average comparing CPR was performed without physical load and CPR was performed after moving the equipment while wearing personal protective equipment. In the third quartile, it increased to about 11 times. Finally, the change in blood pressure increased by 26.6 mmHg on average comparing CPR was performed without physical load and with wearing personal protective equipment after moving the equipment, and increased by 31.2 mmHg on average in the third quartile.

• 한국해양공학회지
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• 제37권3호
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• pp.89-98
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• 2023

Analyzing the interactions of free surface waves caused by a submerged-body movement is important as a fundamental study of submerged-body motion. In this study, a two-dimensional mini-towing tank was used to tow an underwater body for analyzing the generation and propagation characteristics of free surface waves. The magnitude of the maximum wave height generated by the underwater body motion increased with the body velocity at shallow submerged depths but did not increase further when the generated wave steepness corresponded to a breaking wave condition. Long-period waves were generated in the forward direction as the body moved initially, and then short-period waves were measured when the body moved at a constant velocity. In numerical simulations based on potential flow, the fluid pressure changes caused by the submerged-body motion were implemented, and the maximum wave height was accurately predicted; however, the complex physical phenomena caused by fluid viscosity and wave breaking in the downstream direction were difficult to implement. This research provides a fundamental understanding of the changes in the free surface caused by a moving underwater body.

• 대한조선학회논문집
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• 제51권4호
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• pp.265-273
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• 2014

Wave-body interaction is simulated using a developed code based on the flux-difference splitting scheme for immiscible and incompressible fluids and the hybrid Cartesian/immersed boundary method. A free surface is captured as a moving contact discontinuity within a fluid domain and an approximated Riemann solver is used to estimate the inviscid flux across the discontinuity. Immersed boundary nodes are identified inside an instantaneous fluid domain near a moving body, then dependent variables are reconstructed at those immersed boundary nodes based on interpolation along local normal lines to the boundary. Free surface flows around an oscillating cylinder are simulated and the computed wave elevations are compared with other reported results. The generation of a solitary wave by a moving wave-maker is simulated and the time histories of wave elevations at two different points are compared with other results. The developed code is applied to simulate body motion of an elastically mounted circular cylinder as a solitary wave passes the body. The force acting on an elastically mounted cylinder is compared with the force acting on a fixed cylinder. Grid independency of the computed body motion is established based on a comparison of results using three different-size grids.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 추계학술대회 논문집
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• pp.1252-1254
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• 2004

BMI(brain machine interface) has been recently applied to give a disabled person mobility. This study is to determine the effective EEG parameters for predicting the movement moment of body limbs thought analysis of moving averaged ERD. The results showed that the proposed method for classifying EEG for predicting the movement seemed to be better than the classical method of determining ERD.

• 한국전산유체공학회지
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• 제10권3호
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• pp.70-76
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• 2005

A two-layer incompressible time-accurate Euler solver is applied to analyze flow fields around a submerged body moving at a critical speed near a pycnocline. Discontinuities in the dependent variables across the material interface are captured without any dissipation or oscillation using the ghost fluid method on an unstructured grid. It is shown that the material interlace has significant effects on forces acting on a submerged body moving near a pycnocline regardless of the small difference in densities of two layers. Contrary to the shallow water waves, a submerged body can reach a critical speed at very low Froude number due to the small difference in the densities of the two layers.

• 대한조선학회논문집
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• 제43권6호
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• pp.647-655
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• 2006

In this paper, submerged body dynamics model in vertical plane which can include the effect of free surface and wave is suggested to simulate the motions of submerged body moving beneath free surface precisely. A controller is designed, which can maintain a constant depth below the mean sea level and minimize the pitch angle. Numerical simulations show that the designed controller is effective on depth keeping and minimizing pitch angle in regular waves and irregular waves.

• 대한한의학원전학회지
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• 제26권4호
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• pp.253-266
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• 2013

Objective : There was no attempt to understand Moving Energy between two kidneys(腎間動氣) and Kidney on Left & Life Gate on Right(左腎右命門) by integration progress. So I have faced to study based on two parts with concerning as clues. One is 'Life Right (左 右)' and the other is 'Between(間)'. Methods : Revealing the source of the origin, Nanjingbenyi(難經本義) is given on the basis. Take a close look at publications related to Nanjing(難經) which is about Kidney on Left & Life Gate on Right and Moving Energy between two kidneys. Take a close look at Kidney, the Life Gate and Moving Energy between two kidneys. Look see the three-dimensional uplift movement of Gi(氣). Results : In Neijing(內經) and Nanjing, the basic point of view for Kidney is the same. That is explained in line with attributes of convergence(收斂). 'Life Gate(命門)' is a term to express the divergence feature(發散機能) of kidney. Moving Energy between two kidneys is used to mean the mainspring of human body activity. The Gi in human body loses altitude turning left(左旋而下降) and gains height turning right(右旋而上升). Conclusion : Watching on functional aspect, there are two names for kidney. One is 'Kidney(腎)' which collects the losing altitude turning left and the other is 'Life Gate' which rises turning right. Moreover, the fundamental power that effectuate the uplift movement is Moving Energy between two kidneys. This kind model is a way that can be understood syntagmatically the Kidney on Left & Life Gate on Right and the Moving Energy between two kidneys without any gainsaying the original of Nanjing.

• 한국통신학회논문지
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• 제23권8호
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• pp.1998-2009
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• 1998

본 논문에서는 배경의 움직임이 유발되는 능동 CCD 카메라를 통하여 실시간으로 포착되는 영상 데이터를 대상으로 카메라의 사전 설치 정보나 좌표 보정(calibration) 없이 강체(rigid body) 혹은 비 강체(non-rigid body)의 움직이는 물체를 추출하고 이의 이동 방향을 판단하여, 추적하는 효율적인 알고리즘을 제안한다. 이동 물체의 영역분할을 위하여 동체의 형태를 규정하는 특징 점을 추출하고, 시간에 따른 특징 점의 이동 벡터로 구성된 특정 플로우 필드(feature flow field)를 구한 후 이들을 다차원 특정 공간상에서 군집화(clustering)함으로써 동체를 추출한다. 제안하는 IRMAS(lncremenatal Rotational Minimum Angle Search)에 의하여 군집화된 특정점들의 볼록 다각형(convex hull)올 구함으로써 이동 물체의 개괄적인 외곽 형태를 재 구성한다. 또한, 이동 궤적의 갑작스러운 변화를 가져올 수 있는 동작 특성을 가지는 이동 물체의 효과적인 추적을 목적으로 개선된 선형 예측기를 사용하였다. 이동 궤적 예측기는 기존의 선형 예측기의 차수를 이동의 변화도에 따라 적응적으로 조정함으로써 예측 오차를 감소시켜, 빠른 속도로 이동 궤적에 수렴한다.