• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.8
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• pp.27-35
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• 2003

Geometric modeling tool and analysis tool of shell surface have been developed in the different environments and purposes. Thus they cannot be naturally fitted to each other for the integrated design and analysis. In the present study, an integrated framework of geometric modeling, analysis， and design optimization is proposed. It is based on the common representation of B-spline surface patch. In the analysis module, a geometrically-exact shell finite element is implemented. In shape optimization module, control points of the surface are selected as design variables. For the computation of shape sensitivities, semi-analytical method is used. Sequential linear programming(SLP) is adopted for the shape optimization of surfaces. The developed integrated framework should serve as a powerful tool for the geometric modeling, analysis, and shape design of surfaces.

• Journal of the Korean Geotechnical Society
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• v.24 no.9
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• pp.41-48
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• 2008

The aim of this study is to present a graphical method in order to evaluate stages in shrinkage cracking. Firstly, the distribution of crack openings is established by sorting the openings of individual cracks in the soil cracking system. Secondly, it is normalized in a range of 0 to 1 to obtain the normalized crack opening distribution. Thirdly, three S-shape curve models introduced by Brooks and Corey(1964), Fredlund and Xing(1994) and van Genuchten(1980) are chosen to fit the normalized crack opening distribution using a curve fitting method. The accuracy of fitting which is described through fitting parameters by the van Genuchten equation is much higher than that by the Brooks and Corey equation and slightly higher than that by the Fredlund and Xing equation; thus the van Genuchten model is used. Finally, the stages of shrinkage cracking are graphically evaluated by drawing three separate straight lines corresponding to three linear parts of the fitted normalized crack opening distribution. The proposed method is tested with different sample thicknesses. The measured data are fitted by the selected model with the fairly high regression coefficient and small root mean square error. The results show graphically that shrinkage cracking comprises three stages; namely, primary, secondary and residual stages. Subsequently, the ranges of evaluated crack opening for each of these stages are presented.

• Fashion & Textile Research Journal
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• v.12 no.3
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• pp.354-363
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• 2010

The purpose of this study was to provide some preliminary results on application of 3D scan data of head shapes to the hat design and pattern-making. This paper defined necessary measurement items and concepts in 3-dimensional images of head shapes. And also it presented the methodology to pattern-making of 6-piece crown hat based on 3D data. It used the data of Size Korea to pick up and choose a head shape model with the average head size of Korean women in their twenties. Main results were: 1. The 3D scan data of head shape was better than the 1 dimensional measurement data. Because I could establish a hat pattern-making theory by the 3D scan data of head. 2. The 3D scan data provided the basis for conceptualization of basic measurement points and items for a better fit of hats as well as the definition of the basic hat circumference. 3. This presented a methodology for analyzing out head shape by 3D scan data, and allowed the derivation of the basic hat circumference from the maximum head circumference. 4. As the 6-piece Crown cloche hat made by this method fitted the head shape model perfectly, this methodology could suggest potential applicability to various hat design.

• Korean Journal of Health Education and Promotion
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• v.25 no.2
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• pp.61-72
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• 2008

Objectives: This study was conducted to examine the relationships among body image, self-esteem and sociability according to perception of body shape and obesity level. Methods: The subjects in this study were 325 elementary school youngsters in their sixth year. A survey was conducted, and one-way ANOVA, Scheffe test, Pearson's correlation analysis and path analysis were used for data analysis. Results: Normal weight group accounted for 43.4%, under weight group 34.8% and obesity group 21.8%. In underweight group, 53.1% of the subjects perceived their body was normal or fatty while 17% of subjects in normal group perceived their body was fatty. There were significant differences in body image according to the perception of body shape by grade(F=15.90, p=.000) and to the level of obesity(F=6.18, p=.002). There was a significant difference in self-esteem according to the perception of body shape by grade(F=3.17, p=.430). There was a significant difference in sociability according to the level of obesity(F=3.48, p=.032). There was significantly strong positive correlation among their body image, self-esteem and sociability. A structural equation model was tested and fitted the data well. Conclusions: This study suggested that health education is needed to establish the correct body image from the elementary school periods by school health educators. The right body image is more important than anything else to improve self-esteem and sociability.

• The Research Journal of the Costume Culture
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• v.17 no.1
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• pp.15-27
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• 2009

The purpose of this study was to find texture which suitable for the acryl knitted jacket of women in the middle age. The study was carried out 2 parts. The first part was to choose the pattern fitted in the body shape of women in the middle age, and the second part was wearing test with 3 different textured acryl knitted jacket(half milano, milano, jacquard). The usable data of the test were coded for further statistical analysis including descriptive statistics (frequency and one way-ANOVA test, Student-Newman-Keuls Multiple Range Test) by using SPSSWIN 12.0. The results were as follows: It was found that first evaluation for the appearance test on fitness, pattern B(Brand: Morado) were better than the rest of them(pattern A: Trieste, pattern C: Escalier). It was found that second evaluation for the test, jacket with jacquard were better than the rest of them. Acryl knitted Jacket of women in the middle age should made of jacquard. Therefore it should be designed as possible as considering the physical characteristics of knitted materials. It was found that third evaluation for the test, it was opposite results that a general knitted fabric pattern was made smaller than a woven jacket. So, it was necessary that the acryl knitted jacket of women in the middle age follow a similar site tolerance such as a woven jacket. This result was due to a radical change of a middle age women's body shape.

• Journal of the Korean Society of Industry Convergence
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• v.27 no.3
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• pp.555-561
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• 2024

This paper derives material properties of steel bars that simulate the distribution of stress and strain of prestressed tendons used in Prestressed concrete(PSC) girders and presents an optimal material model. ABAQUS software was used to establish the 3D solid model of the PSC girder and strand wire rope for a PS(Prestressed) tendon. Then the model of steel wire rope was imported into the Isight interface plugin directly through the ABAQUS and the Data Matching. In ABAQUS, the contact pairs were established, the models were meshed, the constraints were applied to solve the finite element model and an axial tension of 0.5m/s was loaded to analyze the stress and deformation distributions in the normal working range of the PS strand wire rope. In Data Matching, classical experimental data is fitted to the optimal material properties through finite element analysis and multi-objective optimization. The results show that the steel bar with optimal material properties presents a similar linear area and stress distribution with the PS tendon.

• The Research Journal of the Costume Culture
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• v.11 no.3
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• pp.447-457
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• 2003

The shape of womens breast is the most important part of body silhouette. For the high-fitted clothes, in particular, more refined brassiere effective enough to show the beautiful line of female breast is asked. This study focuses on comparing the difference of the two different textiles of brassiere as to their effectiveness as a brassiere. The Stockman Lingerie Mannequin made by England is used for the draping method for the brassiere pattern. Two different brassieres of stretchable and unstretchable(cotton) textiles respectively were made out of this pattern, and the difference of effectiveness wearing the two brassieres was compared. 30 females ranging in the ages of 19 through 24, and whose size is 75A were selected as the test group who are to wear them. The result of each measurement proves that the cotton brassiere is more effective than the stretchable brassiere as a whole considering center concentration of breast, projection of breast, and bust up function. The result of the test on satisfaction of wearing brassiere was also in favor of cotton brassiere as to projection effect, bust up effect, making a good shape of bust. For the cup, in particular, unstretchable textile is more effective for making a breast look better.

• Journal of the Korean Society of Clothing and Textiles
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• v.40 no.2
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• pp.273-286
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• 2016

Protective coveralls are very uncomfortable to work in comparison to ordinary top and bottom separated clothing. A pattern maker has to consider the size of the human body and human motion range when designing protective coverall patterns. It is difficult to produce well-fitted coveralls because of the lack of readymade patterns despite the increased need for protective coveralls at various jobs. Patterns are decomposed by unsewing 18 products in the domestic market to provide the fundamental information on developing patterns for protective coveralls. The characteristics and differences of pattern types are compared after grouping patterns with information taken from the analysis of the shapes and measurements of patterns from the acquired patterns. The results of the analysis showed that on-market protective coveralls were less curved but much linear when compared to ordinary clothing patterns; however, the breasts and crotch circumferences were very loose and bulky, which is quite different from the other all-in one style working clothes. For the pattern shapes, patterns are classified into waistline-seamed and bustline-seamed types. The result of the hierarchical cluster analysis with 27 measurement variables were classified into four groups. Types by shape and measurements were related to each other; therefore, we expect the information of each type to be used in developing protective clothing patterns.

• International Journal of Aeronautical and Space Sciences
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• v.16 no.2
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• pp.295-310
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• 2015

In the present study, an unstructured mixed mesh flow solver was used to conduct a numerical prediction of the aerodynamic performance of the S-76 rotor in hover. For the present mixed mesh methodology, the near-body flow domain was modeled by using body-fitted prismatic/tetrahedral cells while Cartesian mesh cells were filled in the off-body region. A high-order accurate weighted essentially non-oscillatory (WENO) scheme was employed to better resolve the flow characteristics in the off-body flow region. An overset mesh technique was adopted to transfer the flow variables between the two different mesh regions, and computations were carried out for three different blade configurations including swept-taper, rectangular, and swept-taper-anhedral tip shapes. The results of the simulation were compared against experimental data, and the computations were also made to investigate the effect of the blade tip Mach number. The detailed flow characteristics were also examined, including the tip-vortex trajectory, vortex core size, and first-passing tip vortex position that depended on the tip shape.

• Proceedings of the Korea Water Resources Association Conference
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• 2005.09b
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• pp.842-845
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• 2005

A method for the numerical simulation of two-dimensional free-surface flow resulting from the propagation of regular gravity waves over topography with arbitrary bottom shape is presented. The method is based on the numerical solution of the Euler equations subject to the fully nonlinear free-surface boundary conditions and the appropriate bottom, inflow and outflow conditions using a hybrid finite-differences and spectral-method scheme. The formulation includes a boundary-fitted transformation, and is suitable for extension to incorporate large-eddy simulation (LES) and large-wave simulation (LWS) terms for turbulence and breaking wave modeling, respectively. Results are presented for the simulation of the free-surface flow over two different bottom topographies, with constant slope values of 1:10 and 1:20, two different inflow wave lengths and two different inflow wave heights. An absorption outflow zone is utilized and the results indicate minimum wave reflection from the outflow boundary. Over the bottom slope, lengths of waves in the linear regime are modified according to linear theory dispersion, while wave heights remain more or less unchanged. For waves in the nonlinear regime, wave lengths are becoming shorter, while the free surface elevation deviates from its initial sinusoidal shape.