• 제목/요약/키워드: rectangular cluster

검색결과 34건 처리시간 0.019초

바탕회전하에 회전요동하는 직사각형용기 내의 유동에 관한 연구 (Study on Fluid Flows in a Rectangular Container Subjected to a Background Rotation and a Rotational Oscillation)

  • 박재현;서용권
    • 한국해양공학회:학술대회논문집
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    • 한국해양공학회 2002년도 춘계학술대회 논문집
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    • pp.215-219
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    • 2002
  • In this study, we show the numerical and the experimental results for fluid motions inside a rectangular container subjected to a background rotation added by a rotational oscillation. In the numerical computation, we used a parallel computer system of PC-cluster type. Attention is given to dependence of the flow patterns on the parameter change. It shows that the flow becomes in a periodic state at low Reynolds numbers and undergoes a transition to a chaotic motion at high Reynolds numbers. It also shows that the fluid motion tends to be depth-independent at ${\epsilon}$ up to 0.3 for Re lower than 5235.

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중년 남성의 하반신 체형분류에 관한 연구 (A Study on Lower Body Shapes from Classification of Middle Aged Men's)

  • 성옥진
    • 한국의류학회지
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    • 제28권3_4호
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    • pp.499-508
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    • 2004
  • The purpose of this research is to define body characteristics of middle-aged men at ages between 35 and 55 whose physical changes are very prominent, by comparing the measurement data collected from this age group. This research also classifies different body types, and provides basic data for designing slacks' original forms according to each body type. Based on factor analysis of the measured data, seven key factors are grouped. And five different body types are classified based on the cluster analysis using factor marks. Type 1 refers to those who are tall and standard. This body type is characterized by trapezoid body shape when looked from the front, and slim abdomen when looked from the side. Type 2 refers to short and a little fat body shapes, with trapezoid front and protruding hip and abdomen. Type 3 refers to tall and fat body shapes, with rectangular front, protruding abdomen, and slim hip. Type 4 refers to those who are of medium height and a little obese, with rectangular front and protruding abdomen and hip. Type 5 refers to short and obese body shapes, with rectangular front, slim abdomen, and protruding hip. 12 items are available to judge middle-aged men's low body types and the hit ratio is 90%.

평형평판 간극사이에서 PIV를 이용한 ER유체의 유동특성에 관한연구 (A Study on Flow Characteristics of ERF Between Two Parallel-Plate by Using PlV)

  • 정완보;박영석
    • 한국공작기계학회논문집
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    • 제15권1호
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    • pp.56-62
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    • 2006
  • An experimental investigation was performed to study the characteristics of ER(Electro-Rheological) fluid flow in a horizontal rectangular tube with or without D.C voltage. To determine some characteristics of the ER flow, 2D PIV(Particle Image Velocimetry) technique is employed for velocity measurement. This research found the mean velocity distribution with 0kV/mm, 1.0kV/mm and 1.5kV/mm for Re = 0, 0.62, 1.29 and 2.26. When the strength of the electric field increased, the cluster of ERF are clearly strong along the test tube and the flow rate decreased. In this study, the rheology of ER fluid stagnating or flowing through a dispersion meter will be investigated by PIV method. And then the ER effect, which appears at the ER valves and their appliance will be visualized.

3포트 ER 밸브 개발을 위한 분산계 ER유체의 유동특성에 관한 연구 (A Study on Flow Characteristics of Dispersive ER Fluids for Development of 3-port ER Valves)

  • 장문제;장성철;염만오;이동극;김기홍
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 2005년도 춘계학술대회 논문집
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    • pp.125-131
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    • 2005
  • The purpose of the present study is to examine the flow characteristics of ER fluids between 2 port and 3 port rectangular tube brass electrodes. ER fluid is made silicon oil mixed with $2-3wt\%$ starch having hydrous particles. Flow visualization of the ER fluids were obtained by CCD camera measuring those of the clusters using an image processing technique. This research found the flow $rate(Q_L)$ with 0 kV /mm, 0.5kV/mm and 1.0kV/mm for $Q_L\;=\;0,\;0$ and $5.73cm^3/s$. When the strength of the electric field increased, the cluster of ER fluids are clearly strong along the rectangular tube and the flow rate(Q) decreased.

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지수치를 이용한 Plus-size 여성의 하반신 체형 연구 (A Study of Lower Body Shapes of Plus-sized Women to Index)

  • 하희정;성옥진
    • 복식문화연구
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    • 제13권1호
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    • pp.6-17
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    • 2005
  • The purpose of this research is to define low body shapes of Plus-sized women at ages between 21 and 69 whose satisfied the Plus-sized judgment criteria took part in this study. This research also classifies different body types, and provides basic data for designing skirt's and slacks' prototypes according to each body type. Based on factor analysis of the measured data, seven key factors are grouped. And four different body types are classified based on the cluster analysis using factor marks. Type 1 refers to those who are tall in stature and balanced. This body type is characterized by trapezoid body shape when looked from the front, and slim the abdomen, bulge the belly and flat the buttocks when looked from the side. Type 2 refers to short and an obese body shapes, with trapezoid front and bulge abdomen and belly and flat the buttocks. Type 3 refers to those who are of medium height and long-legged body shapes, with rectangular front, protruding belly and buttocks. Type 4 refers to obese body shapes, with rectangular front, protruding abdomen and belly, flat the buttocks. 9 items are available to judge Plus-sized women's low body types and the hit ratio is 93.5%.

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고령사회를 대비한 뉴 시니어 여성의 체간부 체형 분석 (Torso shape analysis of new senior women for the aged society)

  • 어미경;김아영
    • 한국의상디자인학회지
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    • 제21권2호
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    • pp.95-108
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    • 2019
  • This study aims to determine the characteristics of new senior women's torso shapes. The data was collected from the 7th Size Korea, which analyzed 412 women between the ages of 55-69. A factor analysis was performed based on 20 indices, including eight based on circumference, eight based on height and length measurements, and four based on torso flattening. The results of the factor analysis suggest five main factors: torso silhouette, longitudinal size of the body, torso flattening rate, abdominal shape, and posterior longitudinal size. The results of the cluster analysis suggest three overall types: Type 1 is the inverted triangular obese shape which is characterized by large breasts, small buttocks, a short height, and a forward-bending posture; Type 2 is the rectangular, slim shape which is characterized by a forward neck and a flat front and back of the torso, and is the most slender among the three types; Type 3 is the large rectangular, overall obese shape, which is characterized by a round shape with large breasts, waist, and buttocks, and a forward-bending posture with a protruding back, and this is the most obese type. According to the results of the cross-tabulation, women aged 55-59 showed no trend in body shape; women aged 60-64 showed an increases in the inverted triangular obese shape and the large rectangular, overall obese shape; women aged 65-69 showed an increase in the large rectangular, overall obese shape and a decrease in the rectangular slim shape. In summary, new senior women showed body shape characteristics of being short, more obese having, a bent over posture. As they grew older, the curves disappeared, and the body becomes rounder. The study found that variation in body shape exists among new senior women in the aged society.

Biomechanical Finite Element Analysis of Bone Cemented Hip Crack Initiation According to Stem Design

  • Kim, Byeong-Soo;Moon, Byung-Young;Park, Jung-Hong
    • Journal of Mechanical Science and Technology
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    • 제20권12호
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    • pp.2168-2177
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    • 2006
  • The purpose of this investigation was to determine the specific fracture mechanics response of cracks that initiate at the stem-cement interface and propagate into the cement mantle. Two-dimensional finite element models of idealized stem-cement-bone cross-sections from the proximal femur were developed for this study. Two general stem types were considered; Rectangular shape and Charnley type stem designs. The FE results showed that the highest principal stress in the cement mantle for each case occurred in the upper left and lower right regions adjacent to the stem-cement interface. There was also a general decrease in maximum tensile stress with increasing cement mantle thickness for both Rectangular and Charnley-type stem designs. The cement thickness is found to be one of the important fatigue failure parameters which affect the longevity of cemented femoral components, in which the thinner cement was significantly associated with early mechanical failure for shot-time period.

병렬계산에 의한 비축대칭 3차원 스핀업 유동해석 (Analysis of Three-dimensional Nonaxisymmetric Spin-up by Using Parallel Computation)

  • 박재현;최윤환;서용권
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2001년도 춘계학술대회논문집E
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    • pp.512-517
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    • 2001
  • In this study, spin-up flows in a rectangular container are analysed by using three-dimensional computation. In the numerical computation, we use the parallel computer system of PC-cluster type. We compared our results with those obtained by two-dimensional computation. Effect of velocity and vorticity on the flow is studied. The result shows that two-dimensional solution is in good agreement with the 3-D result. Attention is given to the region where the 3-D flow is significant.

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Simple Recursive Approach for Detecting Spatial Clusters

  • Kim Jeongjin;Chung Younshik;Ma Sungjoon;Yang Tae Young
    • Communications for Statistical Applications and Methods
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    • 제12권1호
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    • pp.207-216
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    • 2005
  • A binary segmentation procedure is a simple recursive approach to detect clusters and provide inferences for the study space when the shape of the clusters and the number of clusters are unknown. The procedure involves a sequence of nested hypothesis tests of a single cluster versus a pair of distinct clusters. The size and the shape of the clusters evolve as the procedure proceeds. The procedure allows for various growth clusters and for arbitrary baseline densities which govern the form of the hypothesis tests. A real tree data is used to highlight the procedure.

An Experimental Study on Flow Characteristics of ERF Between Two Parallel-Plate Electrodes by Using PIV Technique

  • Chang, Tae-Hyun;Jang, Sung-Cheol
    • Journal of Mechanical Science and Technology
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    • 제18권10호
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    • pp.1763-1771
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    • 2004
  • An experimental investigation was performed to study the characteristics of ER (Electro-Rheological) fluid flow in a horizontal rectangular tube with or without D. C voltage. To determine some characteristics of the ER flow, 2D PIV(Particle Image Velocimetry) technique was employed for velocity measurements. This research found the mean velocity distributions with 0kV /mm, l.0kV /mm and l.5kV /mm for Re=0, 0.62, 1.29 and 2.26. When the strength of the electric field increased, the cluster of ERF was clearly strong along the test tube and the flow rate decreased. The present results will contribute to the economical and compact design of ER fluids system.