• Journal of the Korean Society for Precision Engineering
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• v.24 no.12
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• pp.20-28
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• 2007

• Proceedings of the Korea Society for Simulation Conference
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• 1999.04a
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• pp.138-142
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• 1999

심장의 수축 및 이완기에서의 좌심실 벽 움직임은 허혈 및 심근경색증과 같은 심장질환에서 영상적 진단의 주요한 특징이다. 심장은 동적 기관으로써 진단을 위해서는 속도와 같은 4차원 파라미터의 추정이 필요하다. 본 논문에서는 심장의 좌심실 형태 및 움직임을 모델링하여 동적으로 가시화하는 방법을 제시한다. 본 논문에서는 좌심실을 Dynamic Gaussian Blob 모델로 근사화하였다. 이 모델은 가우시안 함수 기반 FEM 요소와 superellipsoid를 통합한 것으로 좌심실의 형태 및 벽의 움직임을 물리기반 방법에 의해 묘사할 수 있다. 즉, 일련의 영상들로부터 좌심실 벽에 대응되는 3차원 점들을 추출한 후 이 점들에 작용되는 힘에 의해 박동하는 좌심실의 움직임을 추적한다. 이와 같은 좌심실 벽 움직임 시뮬레이션은 심장 움직임에 이상이 있는 질환의 진단을 위한 빠르고 간편한 보조 도구로써 사용되어질 수 있다.

• Journal of Biomedical Engineering Research
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• v.22 no.2
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• pp.211-216
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• 2001

본 연구에서는 상지의 동적 운동시, 상지의 주요 구동요소로서 주요 근육인 전박부 굴곡근, 신전근 및 이두박근 및 삼두박근의 근육들의 근전도를 측정하고, 이와 함께 동적 운동시의 주관절에 발생하는 관절모멘트, 근력, 근전도의 연관관계를 정량적으로 규명함으로써, 해당하는 근육의 근전도만의 측정으로 동적운동 시 필요한 근력의 정량적인 예상을 가능케 하는 수학적 모델을 제시하고자 하였다. 지금까지의 기존 연구는 근력의 등척성 수축운동에서의 근력 예측으로서, 실제 일상 생활에서 발생하는 인체내의 동적운동 상황에서의 근력을 산정 하는데 있어서 제한적 한계를 갖고 있었다. 따라서 본 연구는 실시간 동적 운동시 측정되는 근전도를 이용하여 해당하는 근육의 근력을 예측할 수 있는 수학적 모델을 제시하고자 하였다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.3D
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• pp.435-444
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• 2006

This paper investigates the effect of 3-dimensional FE models to evaluation results of jointed concrete pavements which is back-calculated by AREA method. Sensitivity of 3-dimensional FE models developed to simulate the behavior of real jointed concrete pavement are analyzed after compared with 2-dimensional FE models using ILLISLAB. In comparison with 2-dimensional models, influence of concrete contraction under loading plate and base layer on surface deflections is more than that of loading configuration. Deflections at 3-dimensional model between linear and nonlinear temperature distribution under same temperature difference are similar, but noticeable differences are investigated in low elastic modulus of foundations. Dynamic deflections under loading plate are larger than static deflections in high elastic modulus of foundation, but smaller in low elastic modulus. Lower dynamic modulus of subgrade reactions are backcalculated by dynamic deflections than by static deflections. But reverse trend is investigated in the backcalculated elastic modulus of concrete which describes trends of the field backcalculation values calculated from AREA method.

• The Journal of the Acoustical Society of Korea
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• v.28 no.1
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• pp.25-31
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• 2009

This paper introduces a spectrally formulated element method (SEM) for the beams treated with passive constrained layer damping (PCLD). The viscoelastic core of the beams has a complex modulus that varies with frequency. The SEM is formulated in the frequency domain using dynamic shape functions based on the exact displacement solutions from progressive wave methods, which implicitly account for the frequency-dependent complex modulus of the viscoelastic core. The frequency response function and dynamic responses obtained by the SEM and the conventional finite element method (CFEM) are compared to evaluate the validity and accuracy of the present spectral PCLD beam element model. The spectral PCLD beam element model is found to provide very reliable results when compared with the conventional finite element model.

• Journal of the Korea Computer Industry Society
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• v.2 no.10
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• pp.1291-1300
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• 2001

This article come to study the visualization representation technique of eye brain of person, basing on the ground of the dynamic graphics which is able to change the real time, manipulating the image as graphic factors of the multi-data. And the important thought in such realization is as follows ; corresponding the character points of human face and the parameter control value which obtains basing on the existing image recognition algorithm to the multi-dimensional data, synthesizing the image, it is to create the virtual image from the emotional expression according to the changing contraction expression. The proposed DyFIG system is realized that it as the completing module and we suggest the module of human face graphics which is able to express the emotional expression by manipulating and experimenting, resulting in realizing the emotional data expression description and technology.

• Journal of Ocean Engineering and Technology
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• v.12 no.2 s.28
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• pp.1-21
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• 1998

In this paper, a non-conforming 3-D 8-node solid element(MQM10) has beets applied to the analyses of static and dynamic bending problems of laminated composite plates The QM10 element exhibits stiffer bending stiffness which is caused by the reduction of degree of freedom from Q11 element. As an effective way to correct the relative stiffness stiffening phenomenon the modification of Gauss sampling points for composite plates is proposed. The quantity of modification is a function of material properties. Also, another two modified equations are obtained, one is modification for stress, and the other is modification of coefficient of shear modulus in free vibration. It is noted that MQM10 element can analyse the static and free vibration problems of various 3-dimensional composite plates composed of unidirectional laminae, woven laminae or braided laminae. The results of MQM10 element are in good agreement with those of 20-node element.

• Magazine of the Korea Concrete Institute
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• v.20 no.6
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• pp.28-35
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• 2008

The Burj Dubai Project will be the tallest structure ever built by man; when completed the tower will be more than 700 meter tall and more than 160 floors. While the early integration of aerodynamic shaping and wind engineering considerations played a major role in the architectural massing and design of this multi-use/residential tower, where mitigating and taming the dynamic wind effects was one of the most important design criteria, the material selection for the structural systems of the tower was also a major consideration and required detailed evaluation of the material technologies and skilled labor available in the market at the time Concrete was selected for its strength, stiffness, damping, redundancy, moldability, free fireproofing, speed of construction, and cost effectiveness. In addition, the design challenges of using concrete for the design of the structural system components will be addressed. The focus on this paper will also be on the early planning of the concrete works of the Burj Dubai Project.

• Journal of the Korean Institute of Landscape Architecture
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• v.44 no.5
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• pp.38-46
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• 2016

The purpose of this study was to quantitatively examine the physiological and psychological effects of a waterscape facility in an interior landscape space. Data were collected as participants under stress relaxed in either an interior space with greenery(Type G) or an interior space with a waterscape facility(Type W). The participants relaxing in the Type W space showed significantly decreased systolic and diastolic blood pressures, and an impression evaluation by the SD method indicated that their impressions were expressed in more positive terms, such as 'vigor', 'dynamism', 'pleasantness', and 'vitality'; when compared to participants relaxing in the Type G space. A POMS analysis showed waterscape elements influenced participants' psychological mood states by decreasing tension and fatigue, but increasing vitality. Introduction of waterscape facilities into interior landscape spaces could therefore provide stressed individuals with health benefits, including decreased blood pressure and positively changed psychological mood states.

• Explosives and Blasting
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• v.22 no.4
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• pp.7-15
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• 2004

An explosion modeling technique was developed by using the spherical discrete element code, PFC3D, which can be used to model the dynamic stress wave propagation phenomenon. The modeling technique is simply based on an idea that the explosion pressure should be applied to a PFC3D particle assembly not in the form of an external force (body force), but in the form of a contact force (surface force). According to this concept, the explosion pressure is applied to the wall particles by the scheme of radius expansion/contraction of inner-hole particles. The output wall force is compared to the input hole pressure in every time step, and a correction routine is activated to control the radius multiplier of the inner-hole particles. A comparative blast simulation far a cement mortar block of $80\times90\times80mm$ was conducted by using the conventional explosion modeling method and the new one. The results of the simulation are presented in a qualitative fashion.