• Title/Summary/Keyword: shapes area

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Study of the effect of varying shapes of holes in energy absorption characteristics on aluminium circular windowed tubes under quasi-static loading

  • Baaskaran, N;Ponappa, K;Shankar, S
    • Structural Engineering and Mechanics
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    • v.70 no.2
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    • pp.153-168
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    • 2019
  • In this paper, energy absorption characteristics of circular windowed tubes with different section shapes (circular, ellipse, square, hexagon, polygon and pentagon) are investigated numerically and experimentally. The tube possesses the same material, thickness, height, volume and average cross sectional area which are subjected under axial and oblique quasi-static loading conditions. Numerical model was constructed with FE code ABAQUS/Explicit, the obtained outcome of simulation is in good matching with the experimental data. The energy absorbed, specific energy absorption, crash force efficiency, peak and mean loads along with the collapse modes with their initiation point of simple and windowed tubes were evaluated. The technique for order of preference by similarity ideal solution (TOPSIS) approach was employed for assessing their overall crushing performances. The obtained results confirm that efficacy of crash force indicators have improved by introducing windows and tubes with pentagonal and circular windows achieves the maximum ranking about 0.528 and 0.517, it clearly reveals the above are best window shapes.

Static Optimal Shapes of Tapered Beams with Constant Volume (일정체적 변단면 보의 정적 최적 단면)

  • Lee Tae-Eun;Kang Hee-Jong;Kim Kwon-Sik;Lee Byoung-Koo
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2005.04a
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    • pp.79-86
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    • 2005
  • This paper deals with the static optimal shapes of simple beams which are subjected to a vertical point load. The area and second moment of inertia of the regular polygon cross-section of the tapered beams are determined, which have always same volume and same length for the parabolic taper. The differential equation governing the elastic curve is derived using the small deflection theory and solved numerically. By using the numerical results of deflections, rotations and bending stresses of such beams, the optimal shapes, namely, optimal section ratios, of the beams subjected to a single point load according to variation of load position parameters are determined and presented in the figures. Examples of the static optimal shapes for beams with a single load and multiple loads are reported. The design process of this study can be used directly for the minimum weight design of simple beams.

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Classification of adult male torso shapes using 3D body scan data (3D 스캔 데이터에 의한 성인 남성의 체간부 형태 유형화)

  • Hong, Eun-Hee
    • Journal of the Korea Fashion and Costume Design Association
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    • v.21 no.4
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    • pp.165-179
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    • 2019
  • This study used 3D body scan data to classify body shapes according to the torso shape of adult males aged 20-75 years. This data will be provided so that the apparel industry can make apparel products corresponding to body characteristics by age. The study used 1,796 adult males between the ages of 20 and 75 and the 3D body shape data of the '5th Research on National Standard Anthropometry'. For data analysis, the program SPSSWIN Ver. 17.0 was used to calculate the mean and frequency allowing for a factor analysis, cluster analysis, analysis of variance, and Duncan test. To classify body shape according to the torso shape of adult males, this study considered nine factors: 'horizontal size of torso,' 'vertical size of body,' 'curve of torso and waist-abdomen flatness ratio,' 'length of torso,' 'shape of neck area,' 'degree of lateral curve,' 'difference between front and back interscye length,' 'shoulder armscye shape,' and 'chest flatness ratio.' Based on the results of the factor analysis, the torso shapes of adult males were classified into five types. Type 1 is "upright body with flat, curvy shape", Type 2 is "curve sway back body type", Type 3 is "flat, abdominally obese body", Type 4 is "obese, crooked body" and Type 5 is "thick sway front body type." named.

A Study on the Movement-Fitness according to the Surface changing of Lower-Limb -On the Movements and Shapes of Lower-limb- (하복의 체표변화에 따른 동작적합성에 관한 연구 -하복동작 및 체형을 중심으로-)

  • 박영득;서영숙
    • Journal of the Korean Society of Clothing and Textiles
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    • v.20 no.2
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    • pp.257-269
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    • 1996
  • The puropose of this study was to investigate the movement-fitness according to the surface changing of lower limb The experimental items were divided into the lower limb movements (5) and body-shapes (7). This study was done by the expansion and contraction rate consideration of length, girth Also, the lower half of body shape-change on the movements and body-shapes by flat shell was done simultaneously. The summarized findings resulted from experiments and investigation are suggested as follows; First, when commpared the expansion and contraction rate of the length and girth items, the expansion rate of the back crotch length (14~20%), hip girth (10~ 21%) and knee girth (6.2~18.5%) in rabbit leap movement was the most notable among all variables considered in this experimentation. On the others hand, the front croth length (-22~-52%) contracted remarkably. And big-thigh type was the most notable on the body-shape comparision. Second, in comparision of the expansion and contraction rate of the area on the blocks, the expansion of the hip (50~200%) and knee (51~74%) block was the most remarkable. Especially, in the sit on knees movement of the hip-down type expanded 209.4%. Third, in comparision of the lower half of body shape-change, on the movements and body- shapes by the flat shell, under the influence of knee-joint and hip-joint the shape-changs of the hip and knee block was the most notable. But the shape-change of the waist, abdomen, calf, and ankle was feeble.

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Comparison of Satisfaction with the Size of Ready-made Clothing between Normal and Obese Women in the Busan and Gyeongnam Area (부산.경남지역 표준여성과 비만여성의 기성복 치수 만족도 비교)

  • Oh, Young-Soon;Lee, Jeong-Ran
    • The Korean Journal of Community Living Science
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    • v.19 no.1
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    • pp.21-30
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    • 2008
  • This study conducted a survey to compare the size of ready-made clothes for different body shapes and body sizes, and to discover the differences in satisfaction with the size of ready-made clothes. The subjects were women in their 208 and 308 from Busan and Gyeongnam. The women were classified into groups: normal weight, overweight, and obese, using the Body Mass Index (BMI). The comparison of the body size showed a significant difference among the shapes; the average BMI in overweight women was 24.2 while that of obese women was 27.6. For the clothing size for each body shape, obese women most often wore size 77 and size 88, regardless of the sizes of upper and lower garments. The size consistency of upper and lower garments was the lowest in obese women. However, in most of the shapes, women tended to choose larger-sizes for lower garments than for upper ones. The more obese the subject, the less inclined they were to wear garments for their real body size. Satisfaction with the clothing size was significantly different between body shapes; the more obese, the lower the level of satisfaction with the size. As well, satisfaction with the fit of clothing at certain parts was shown to be low especially in the bust measurement, shoulder width, upper garment length, crotch length, and thigh circumference. When surveyed about the use of alterations for different body shapes, the results were that over 65% of subjects did not alter upper garments regardless of their body shape. Comparatively, 68% or above of all body shapes did do alterations to lower garments for example, the length of pants or skirts.

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Lateral Body Shapes of Males in Their 20s for the Development of Educational Dress Forms (Part 2)

  • Yoo, Hyun;Shim, Boo-Ja
    • Journal of Fashion Business
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    • v.9 no.3
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    • pp.47-63
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    • 2005
  • The study with the subjects at 200 adult males in Busan in their 20s had a purpose at analyzing lateral body shapes to develop men's educational dress forms. The following are the conclusions: 1. Comparison at the Body Dimensions at Busan Male Adults in Their 20s and the 5th Survey at Korean Body Measurement In the comparison at the Busan and national body dimensions by way at Mollison's relative deviation, all compared items were under the deviation of 0.7. Therefore, the sample of Busan male grown-ups is understood io represent the body shapes of the average Korean male adults in their 20s. 2. Results of Lateral Body Shape Classification From factor analysis, seven factors were produced to explain 75.45% of all variables. Those 7 factors to compose lateral body shapes were hip prominence, back-neck sides, upper body's front-back depth, lateral upper body depth, hip-waist depth, front chest-waist depth, and hip and waist height. Cluster analysis revealed four characteristic lateral body shapes. Type 1 with the appearance rate of 11.70%, named D, had the greatest upper chest angle and tanterior neck lower angle. The front side was more developed. Type 2 with 33.51%, named I, was generally long and slender. Type 3 with 24.47%, named d, had the biggest depth differences in hip-chest as well as more prominent back hip. Type 4 with 30.32%, named q, had the biggest dorsal upper angle and the tiniest chest upper angle as the back area was a little bent.

A Study on The Perceived Breast Shapes of Adult Women according to the Age (성인여성의 연령에 따른 유방형태 인식에 관한 연구)

  • 김영숙
    • Journal of the Korea Fashion and Costume Design Association
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    • v.5 no.1
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    • pp.59-71
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    • 2003
  • The purpose of this study is to provide for the basic data useful to the development of a quality brassiere featuring a good wearing feeling and an effect of reinstating and correcting breast shape. For this purpose, 220 adult women aged between 20 and 59 were sampled to survey their perceived and actual breast shapes. The results of this study can be summarized as follows; 1. Most adult women correctly perceive the changes of their breast shapes as they become older. However, the younger women tend to evaluate their breast as larger than their actual sizes, being more dissatisfied with their breast shapes than older women, while wanting their constitution to be more high and slim. In short, there is a little difference between their perceived and actual breast shapes. 2. The breast shape perceived most by the adult women is "droopy type I"(37.7%), followed by "conical type"(21.8%), "flat type"(16.8%), "semi-circular"(10.8%), "droopy type II"(8.6%) and "extruded type"(5.0%) in their order. The younger women tend to perceive their breasts as "flat", "conical" or "semi-circular", while the older women tend to perceive their breasts as "droopy". 3. According to the increase of age, the items of height were decreased and items of width, depth, circumference and length were increased, being obser and breast point were drooped. so volume and bottom area of breast of 40ㆍ50's women's age group were larger than 20?30's women's age group and breast point width of 40ㆍ50's women was being wider by increase of interior dimensions of breast.

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Effects of Stenting Shapes on the Wall Shear Stress in the Angulated Coronary Stenosis (협착된 관상동맥에 시술된 스텐트형상이 벽면 전단응력에 미치는 영향)

  • Cho, Min-Tae;Suh, Sang-Ho;Yoo, Sang-Sin;Keun, Huk-Moon
    • Proceedings of the KSME Conference
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    • 2001.06e
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    • pp.219-222
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    • 2001
  • The objective of the present study is to evaluate the effects of the stenting shapes on flow velocity and wall shear stress in angulated coronary stenosis by computer simulation. Coronary angiogram and Doppler ultrasound measurement in the patients with angulated coronary stenosis were obtained. Inlet wave velocity distribution obtained from in vivo intracoronary Doppler data was used for the numerical simulation. Spatial pattern of blood flow velocity and recirculation area were drawn through out the selected segment of coronary models. Wall shear stresses in the intracoronary stent models were calculated from three-dimensional computer simulation. A negative shear stress region, which is consistent with re-circulation area on flow pattern, was noted on the inner wall of post-stenotic area of pre-stenting model. The negative shear stress was disappeared after stenting. Shear stress in the post-stenting model was markedly reduced up to about two orders of magnitude compared to that of the pre-stenting model.

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Evaluation of Plastic Collapse Bending Load of Elbows with Thinning Area of Various Shapes (여러 형상의 감육부를 가진 엘보우의 소성붕괴 굽힘 하중의 평가)

  • Shin, Kyu-In;Lee, Sung-Ho;Yoon, Kee-Bong
    • Journal of the Korean Society of Safety
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    • v.23 no.3
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    • pp.17-24
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    • 2008
  • Elbows with various shapes of local wall thinning were numerically analyzed by finite element method to get load-displacement curves and the maximum loads. Results were compared with the experimental data obtained by another study. Elastic-plastic analysis were carried out under the combined loading conditions of internal pressure and in-plane bending loads. Two types of bending loads were considered such as elbow opening mode and elbow closing mode. Also, two different wall thinning geometries were modeled. Wall thinning area located extrados or intrados of elbow inner surface was considered. Longitudinal and circumferential lengths of the thinning area and the thinned thickness were varied for analysis. The results showed that the maximum load of the wall-thinned elbow decreased with increasing of the circumferential thinning length and the thinned thickness in both of extrados and intrados thinning locations in both loading types. The maximum load obtained by the analysis were in good agreement with the experimentally measured maximum load with the same wall thinning type and dimensions. This supports accuracy of the analysis results obtained in this study.