• Journal of computational fluids engineering
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• v.2 no.1
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• pp.46-53
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• 1997

The flow field around a three dimensional minivan-like body has been simulated. This study solves 3-D unsteady incompressible Navier-Stokes equations on a non-orthogonal curvilinear coordinate system using second-order accurate schemes for the time derivatives, and third/second-order scheme for the spatial derivatives. The Marker-and-Cell concept is applied to efficiently solve continuity equation. A H-H type of multi-block grid system is generated around a three dimensional minivan-like body. Turbulent flows have been modeled by the Baldwin-Lomax turbulent model. To validate present procedure, the flows around the Ahmed body with 12.5° of slant angle are simulated. A good agreement with other numerical results is achived. After code validation, the flows around a mimivan-like body are simulated. The simulation shows three dimensional vortex-pair just behind body. The flow separation is also observed on the rear of the body. It has concluded that the results of present study properly agreed with physical flow phenomena.

• Proceedings of the Ginseng society Conference
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• 2002.10a
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• pp.277-287
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• 2002

The chemopreventive effects of ginseng on rat carcinogenesis models were investigated, In the present study, the inhibitory effects of white and red ginseng on tumor development were examined using medium-term liver, initiation and medium-term multi-organ carcinogenicity bioassay systems. No modifying potential of the ginsengs was evident in terms of the numbers or areas of glutathione S-transferase placental form (GST -P)-positive foci, which is a marker of preneoplastic lesion in rat livers. However, white ginseng, but not red ginseng was found to decrease the incidences of adenocarcinoma of the small intestine and colon in the medium-term multi-organ carcinogenesis model. These results indicate that white ginseng may have inhibitory effects on progression stage of rat intestinal carcinogenesis, but the influence is not strong. Ginseng is unlikely to have promoting or inhibitory effects in other organs under the present type of experimental conditions. Possible application on ginseng for chemoprevention of colon cancer in humans, can be concluded given the lack of obvious adverse effects.

• Journal of the Korean Society for Precision Engineering
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• v.25 no.8
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• pp.37-44
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• 2008

Nowadays, the increasing global competition forces manufacturer to reduce the cost and time for implementation of manufacturing system. The AR(augmented reality) technology as a new human-machine interface introduces a noteworthy perspective for a new manufacturing system design. Using AR technology, a physically existing production environment can be superimposed with virtual planning objects. Therefore, the planning tasks can be validated without modeling the surrounding environment of the production domain during short process planning time. In this paper, we introduce the construction of AR browser and determine the optimal environment parameters for field application of AR system through lots of tests. And, many methods such as multi-marker coordinate system, division of virtual objects and so on, are proposed in order to solve the problems suggested from initial field test. Based on these tests and results, the test-bed of C/Pad assembly system is configured and robot program for C/Pad assembly is generated based on AR system.

• Journal of Ocean Engineering and Technology
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• v.11 no.2
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• pp.70-76
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• 1997

수치격자의 크기제한에 의한 자유표면 유동해석 문제를 효율적으로 다루기 위하여 자유표면의 모든 격자를 x 방향으로 4,8,12개로 등분할 하고, y 방향으로는 4개로 잘라서 계산하였다. 이중격자 또는 삼중격자로 Navier-Stokes 방정식의 각항에 크기가 다른 격자를 사용해 효율을 향상시키는 계산방법의 연장으로, 본 논문에서는 자유표면 방정식에 보다 세분화된 격자를 적용해, Marker Particle 이동 및 자유수면 형성에 효율향상을 줄수 있는 수치방법을 도입하였다. 계산결과에 의하면 초기사용 격자가 coarse한 경우가 본방법의 효과가 커짐을 알 수 있고 대상물로는 층류유동에서 Wigley모형과 낭류유동의 S103 모형이다.

• Journal of computational fluids engineering
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• v.13 no.3
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• pp.51-61
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• 2008

The SMAC (Simplified Marker And Cell) algorithm is extended for an application to thermal non-equilibrium two-phase flows in light water nuclear reactors (LWRs). A two-fluid three-field model is adopted and a multi-dimensional unstructured grid is used for complicated geometries. The phase change and the time derivative terms appearing in the continuity equations are implemented implicitly in a pressure correction equation. The energy equations are decoupled from the momentum equations for faster convergence. The verification of the present numerical method was carried out against a set of test problems which includes the single and the two-phase flows. The results are also compared to those of the semi-implicit ICE method, where the energy equations are coupled with the momentum equation for pressure correction.

• Proceedings of the Korea Multimedia Society Conference
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• 2001.06a
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• pp.553-557
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• 2001

얼굴 표정을 애니메이션하는 것은 얼굴 구조의 복잡성과 얼굴 표면의 섬세한 움직임으로 인해 컴퓨터 애니메이션 분야에서 가장 어려운 분야로 인식되고 있다. 최근 3D 애니메이션, 영화 특수효과 그리고 게임 제작시 모션 캡처 시스템(Motion Capture System)을 통하여 실제 인간의 동작 및 얼굴 표정을 수치적으로 측정해내어 이를 실제 애니메이션에 직접 사용함으로써 막대한 작업시간 및 인력 그리고 자본을 획기적으로 줄이고 있다. 그러나 기존의 모션 캡처 시스템은 고속 카메라를 이용함으로써 가격이 고가이고 움직임 추적에서도 여러 가지 문제점을 가지고 있다. 본 논문에서는 일반 저가의 카메라와 신경회로망 및 영상처리기법을 이용하여 얼굴 애니메이션용 모션 캡처 시스템에 적응할 수 있는 경제적이고 효율적인 얼굴 움직임 추적기법을 제안한다.

• Proceedings of the IEEK Conference
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• 2003.07e
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• pp.1907-1910
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• 2003

This paper describes a method of stereo image composition for mixed reality without camera calibration or complicate tracking algorithm. The proposed system tracks the panel which has blob makers, and composes virtual objects naturally using the method of texture mapping which is often used in geological computer graphics mapping when we do mapping 2D computer graphic data or man-made 2D images. The proposed algorithm makes it possible for us to compose virtual data even in the case that the panel is bent. For composing 3D object, the system uses depth information obtained from stereo image so that we do not need cumbersome procedure of camera calibration.

• 한국전산유체공학회:학술대회논문집
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• 1996.05a
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• pp.46-51
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• 1996

The flow field around a three dimensional minivan-like body has been simulated. This study solves 3-D unsteady incompressible Navier-Stokes equations on a non-orthogonal curvilinear coordinate system using second-order accurate schemes for the time derivatives, and third/second-order scheme for the spatial derivatives. The Marker-and-Cell concept is applied to efficiently solve continuity equation. The fourth -order artificial damping is added to the continuity equation for numerical stability. A H-H type multi-block grid system is generated around a three dimensional minivan-like body. Turbulent flows have been modeled by the Baldwin-Lomax turbulent model. The simulation shows three dimensional vortex-pair just behind body. And the flow separation is also observed the rear of the body. It has concluded that the results of present study properly agree with physical flow phenomena.

• BMB Reports
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• v.50 no.5
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• pp.233-234
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• 2017

Aberrant expression of the polypeptide N-acetyl-galactosaminyltransferase (GALNTs) has been associated with cancer, but their function(s) in metastasis remains elusive. We have recently identified GALNT14, one of the O-GalNAc glycosylation-initiating enzymes, as a prognostic marker for pulmonary relapse in breast cancer patients. Furthermore, we showed that GALNT14 promotes lung metastasis by the following novel mechanisms: 1) enhancing metastasis initiation by inhibiting the anti-metastatic effect of BMP produced from the lung stroma, 2) exploiting growth signals (e.g. FGF) supplied by macrophages, for their growth into macrometastases in the lung environment. These multi-faceted roles of GALNT14 in lung metastasis are achieved by GALNT14-mediated inhibition and activation of the BMP and FGF signaling pathways, respectively. The link among GALNT14, its downstream pathways and lung metastasis, provides us with an opportunity to develop effective therapeutic intervention for breast cancer.

• Proceedings of the Korea Information Processing Society Conference
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• 2018.10a
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• pp.920-922
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• 2018

This paper describes a method to classify simple circular artificial markers on surfaces of a box on the back of hand to detect the pose of user's hand for VR/AR applications by using a Leap Motion camera and two IMU sensors. One IMU sensor is located in the box and the other IMU sensor is fixed with the camera. Multi-layer Perceptron (MLP) algorithm is adopted to classify artificial markers on each surface tracked by the camera using IMU sensor data. It is experimented successfully in real-time, 70Hz, under PC environments.