• Journal of Institute of Convergence Technology
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• v.12 no.1
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• pp.1-5
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• 2022

This paper describes an algorithm for generating a terrain using a noise function and a height map as one of the procedural terrain generation methods. The polygon mesh data structure to represent the generated terrain concisely and render it is also described. The Perlin noise function is used as the noise technique for terrain mesh, and the height data of the terrain is generated by combining the four noise waves. In addition, the terrain height information can be also obtained from actual image data taken from the satellite. The algorithm presented in this paper generates the geometry part of the polygon topography from the height data obtained, and generated a material for texture mapping with two textures, that is, a diffuse texture and a normal texture. The validity of the terrain method proposed in this paper is verified through application examples, and its possibility can be confirmed through performance verification.

• Journal of the Korean Society of Physical Medicine
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• v.18 no.4
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• pp.1-17
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• 2023

PURPOSE: The purpose of this study was to compare how the shoulder height and respiratory function are affected by applying shoulder stabilization exercises and core stabilization exercises that are effective for strengthening the trunk muscles and postural stability for adults with a round shoulder posture (RSP). METHODS: The participants were 28 young adults with RSP. They were assigned randomly to two groups: shoulder stabilization exercise and core stabilization exercise. They performed the exercises for 30 minutes twice a week for four weeks. They measured the shoulder height and respiratory function before and after exercise. RESULTS: No significant difference in shoulder height was found between the groups. A significant decrease in shoulder height was found in the shoulder stabilization exercise group after exercise. The core stabilization exercise group showed a significant decrease after exercise. In respiratory function, no significant difference was found between the groups. The forced vital capacity (FVC) and forced expiratory volume in one second (FEV₁) were increased significantly in the shoulder stabilization exercise group before and after exercise. The FEV₁, FEV₁/FVC, and peak expiratory flow were significantly higher in the shoulder stabilization exercise group after exercise than in the core stabilization exercise group. CONCLUSION: Shoulder stabilization exercise and core stabilization exercise improved the postural alignment and pulmonary function, and the exercises could be helpful in shoulder rehabilitation as well as the clinical part of the treatment of rounded shoulder posture.

• Journal of computational fluids engineering
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• v.21 no.4
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• pp.78-84
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• 2016

In this paper, turbulence models for considering roughness in the open source code(OpenFOAM) was investigated. Wall function in the RANS(Reynolds-averaged Navier - Stokes) turbulence model was modified considering roughness on the flat plate by using roughness function. Correlation between the first layer height in the CFD model and roughness height of the plate was observed, and the most proper roughness function, and the first layer height from the plate wall in the CFD analysis was suggested in this paper.

• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.176-179
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• 2008

In a numerical simulation of open channel turbulent flows, the determination of wall roughness height for wall function was studied. The roughness constant, based on the law-of-the -wall for flow on rough walls, obtained by experimental works for pipe flows is employed in general wall functions. However, this constant of wall function is the function of Froude number in open channel flows. Thus, the wall roughness should be determined by taking into account the effect of Froude number. In addition, the wall roughness should be corresponding to Manning's roughness coefficient widely used for open channels. In this study, the relation between wall roughness height as an input condition and Manning's roughness coefficient was investigated, and an equation for effective wall roughness height considering the characteristics of numerical models was proposed as a function of Manning's roughness coefficient.

• New & Renewable Energy
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• v.3 no.1 s.9
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• pp.13-19
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• 2007

A triangular fin with variable fin base thickness and base height is analyzed and optimized for the fixed fin base height using a two-dimensional analytical method. At the middle of the fin length, the variation of the temperature along the fin height is listed. The influences of the fin length, base thickness and base height on the heat loss and fin efficiency are analyzed, The optimum heat loss, corresponding optimum efficiency and optimum fin length as a function of the fin base thickness are presented. The optimum heat loss and optimum fin tip length as a function of the convection characteristic number are represented.

• Journal of Welding and Joining
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• v.24 no.5
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• pp.29-36
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• 2006

In this study, an experimental method for the selection of optimal welding condition was proposed in the fillet weld which was done over the tack weld. This method used the response surface analysis in which the leg length and the reinforcement height were chosen as the quality variables of the weld bead profile. The overall desirability function, which was combined desirability function fur the two quality variables, was employed as the objective function for getting the optimal welding condition. In the experiments, the target values of the leg length and the reinforcement height are 6m and zero respectively for the horizontal fillet weld of 10mm thickness mild steel. The optimal welding conditions could predict the weld bead profile(leg length and reinforcement height) as 6.00mm and 0.19mm without tack weld and 6.00mm and 0.48mm with tack weld. from a series of welding test, it was revealed that a uniform weld bead can be obtained by adopting the optimal welding condition which was determined according to the method proposed.

• Korean Journal of Clinical Laboratory Science
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• v.41 no.3
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• pp.135-139
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• 2009

Pulmonary function test has been know to be greatly affected by body indices, such as sex, age, height, body weight, body surface area (BSA) and body mass index (BMI), so hat this study was focused to see the relationship between body index and flow-volume curves. Subjects were 156 (male 90, female 66) and they were examined for pulmonary function test in terms of body index and correlation/multiple regression analysis of flow-volume curves at Presbyterian Medical Center from March to August, 2009. The followings results after analyzing the correlation between body index and flow-volume curves. Although flow-volume curve FEF25-75% showed close correlation with age, body weight, and body surface area, but not with body mass index. In addition, multiple regression analysis was performed to see how each body index affects flow-volume curve FEF25-75%, and FEF25-75% dispersion was explained as 74.5% with age only, 94.2% with age and height, and 96% with age, height, and sex. Therefore, sex, age and height that are mainly used for predictive formular of pulmonary function test and nomogram were important factors for pulmonary function test itself, and further study must be done for other body index.

• Architectural research
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• v.4 no.1
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• pp.1-6
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• 2002

Every year new tall buildings are being conceived, designed, and built with new schemes. Thus it is important to explore the factors that affect tall building design. Thus it is important to explore the tall building design factors. The planning and design of tall buildings require different criteria than those that exist in regular size buildings. Tall buildings are uniquely expressed by their structural systems where exterior esthetic and requirements of space drive the form and composition of the structural systems. Therefore the exploration of design factors is the key to achieve optimum building systems. Optimization as mentioned here is associated with the efficiency of the different building systems. To achieve an optimal system, there is a need for an understanding of the factors that affect on overall tall building design such as planning module, building function, lease span, floor-to-floor-height, building height (aspect ratio), structural system, environmental systems. In this paper a statistical approach will be used and will be based on data collected from the practice through a rigorous survey taken. This information is tabulated and analyzed. The major target of investigation will be lease span related to space requirement in the tall building planning. Factors related to lease spans, such as function, floor-to-floor height, planning module, building height, overall plan dimension, and plan ratio (building geometry), will be looked at carefully. IN conclusion, this approach of optimization can introduce a preliminary design guideline for tall building projects. The purpose of the paper should shed some light on the optimum tall building design criteria.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.735-740
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• 2003

In this study, a numerical optimization to find the optimal shape of streamwise periodic ribs mounted on both of the principal walls is performed to enhance turbulent heat transfer in a rectangular channel. The optimization is based on Navier-Stokes analysis of flow and heat transfer with $k-{\varepsilon}$ turbulence model and is implemented using response surface method. The width-to-height ratio of a rib, rib height-to-channel height ratio, rib pitch to rib height ratio and distance between opposite ribs to rib height ratio are chosen as design variables. The object function is defined as a function of heat transfer coefficient and friction drag coefficient with weighting factor. Optimum shapes of the rib have been investigated for the range of 0.0 to 0.1 of weighting factor.

• Korean Journal of Clinical Laboratory Science
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• v.36 no.2
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• pp.199-204
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• 2004

Height has become one of the most important factors to determine the pulmonary function test index, and there is a high correlation between them, so that they have been utilized for evaluating pulmonary function test predictive value or nomogram. Therefore, we have tried to find out that difference and if there is any correlation and linear relationship between height and forced expiratory flow curve. There were a total of 163 subjects, male 93 and female 70. This study was done at the Department of Pulmonary Function Test of Jeon-Ju Presbyterian Hospital and we measured the index at the forced expiratory flow curve of FVC, $FEV_{1.0}$, $FEV_{1.0}$/FVC, $FEF_{25-75%}$, and $FEF_{200-1200m{\ell}}$. When we subjected the group of height more than 160cm, there were gradual increments at FVC(p<0.001), $FEV_{1.0}$(p<0.001), $FEF_{25-75%}$(p<0.05) and $FEF_{200-1200m{\ell}}$(p<0.001), but no changes at $FEV_{1.0}$/FVC in terms of forced expiratory flow curve index. We have analyzed the relationship between height and forced expiratory flow curve, there was a close relationship at FVC(r=0.670, p<0.01), $FEV_{1.0}$(r=0.491, p<0.01), $FEF_{25-75%}$ (r=0.175, p<0.05) and $FEF_{200-1200m{\ell}}$(r=0.370, p<0.01) but there was reciprocal relationship at $FEV_{1.0}$/FVC(r=-0.215, p<0.01). We have tried simple regression analysis to see if height affects forced expiratory flow curve index as a sector, and the result was $FVC(\ell)=0.0642{\times}height(cm)-7.2978$(p<0.01, $R^2=0.449$), $FEV_{1.0}(\ell)=0.0407{\times}height(cm)-4.2774$ (p<0.01, $R^2=0.2411$), $FEV_{1.0}/FVC(%)=-0.2892{\times}height(cm)+121.44$(p<0.01, $R^2=0.0464$), $FEF_{25-75%}(\ell/sec)=0.0176{\times}height(cm)-0.7876$(p<0.05, $R^2=0.0237$), $FEF_{200-1200m{\ell}}(\ell/sec)=0.0967{\times}height(cm)-11.037$(p<0.01, $R^2=0.1214$) this was approved statistically. According to this study, if height is taller than average, forced expiratory flow curve index were increased, there was a close relationship between height and forced expiratory flow curve, and there was a linear relationship as sector between height and forced expiratory flow curve index. Therefore, researches that study other factors such as sex, age, weight, body surface area, and obesity indexes other than height should be done to see if there are any further relationships.