• Title/Summary/Keyword: cross-sectional shape

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Out-line Space-Shape Variation of Clothing Fitness with Body by Useing the Image Processing (영상처리법을 이용한 의복의 착의 공간 형상 변화)

  • 이수정;윤진경;홍정민
    • Korean Journal of Human Ecology
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    • v.2 no.1
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    • pp.110-113
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    • 1999
  • Clothing shape is principally described in seven factors that are composed of clothing design, clothing material, clothing size, pattern design, sewing method and body motion etc. The aims of this study was to measurement out-line space-shape variation of clothing fitness with body by using the image processing. The subjects for direct anthropometric measurements were 248 female college students aged from 19 to 22. The data were statistically analyzed by principal analysis and cluster analysis. The results selected one somatotype. for the out-line space-shape variation of clothing fitness with body, there dimensional clothing shapes measured. and cross-sectional clothing shape obtained by the measurement was considered to be space wave form. The out-line space-shape variation of clothing fitness with body was observed between the node number and amplitudes of clothing wave form, and node number was determined at the maxim of space-shape amplitude, and the space-shape amplitudes have related with aspect ratio of cross-sectional shape. (Korean J of Human Ecology 2(1) :110-113, 1999)

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Displacement Dependency and Capacity Evaluation According to the Cross-Sectional Shape and Aspect Ratio of Steel Rod Dampers (강봉댐퍼의 단면형상과 형상비에 따른 변위의존성 및 성능 평가)

  • Hyun-Ho Lee
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.27 no.5
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    • pp.89-96
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    • 2023
  • In this study, the displacement dependence, strength, and energy dissipation capacity of the steel rod damper were evaluated. The test variables were cross-sectional shape and aspect ratio. The 6th test specimens were made for performance test. From the test results, it was evaluated that the displacement dependence conditions of design code were satisfied in all specimens. And the strength effect according to the cross-sectional shape was minimal. As a result, the strength and energy dissipation capacity of the aspect ratio of 13.7 were evaluated as excellent.

Vibration Characteristic Analysis of a Duel-cooled Fuel Rod according to the Cross-sectional Dimensions and the Span Length (이중냉각 연료봉의 단면치수와 스팬길이에 따른 진동특성해석)

  • Lee, Kang-Hee;Kim, Jae-Yong;Lee, Yung-Ho;Yoon, Kyung-Ho;Kim, Hyung-Kyu
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.17 no.9
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    • pp.819-825
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    • 2007
  • Vibration characteristics of an duel-cooling cylindrical fuel rod, which was proposed as a candidate design of fuel's cross section for the ultra-high burnup nuclear fuel, according to the cross-sectional dimensions and the number of supports or the span length were analytically studied. Finite element(FE) modeling for the annular cross sectional fuel was based on the methodology, that have been proven by the test verification, for the conventional PWR nuclear fuel rod. A commercial FEA code, ABAQUS, was used for the FE modeling and analysis. A planar beam element (B21) that uses a linear interpolation was used for the fuel rod and a linear spring element for the spring and dimple of the SG. Natural frequencies and mode shape were calculated according to the preliminary design candidates for the fuel's cross sectional dimension and the number of span. From the analysis results, the design scheme of the annular fuel compatible to the present PWR nuclear reactor core was discussed in terms of the number of supports and fuel's cross section.

Type Classification and Shape Display of Brazing Defect in Heat Exchanger (열교환기 브레이징 결함의 유형 분류 및 형상 디스플레이)

  • Kim, Jin-Young
    • Journal of Institute of Control, Robotics and Systems
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    • v.19 no.2
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    • pp.171-176
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    • 2013
  • X-ray cross-sectional image-based inspection technique is one of the most useful methods to inspect the brazing joints of heat exchanger. Through X-ray cross-sectional image acquisition, image processing, and defect inspection, the defects of brazing joints can be detected. This paper presents a method to judge the type of detected defects automatically, and to display them three-dimensionally. The defect type is classified as unconnected defect, void, and so on, based on location, size, and shape information of defect. Three-dimensional display which is realized using OpenGL (Open Graphics Library) will be helpful to understand the overall situation including location, size, shape of the defects in a test object.

Study on Lubrication Characteristics of Spool Valve with Various Cross-sectional Groove Shapes (다양한 그루브 단면형상에 대한 스풀밸브의 윤활특성 연구)

  • Hong, Sung-Ho;Son, Sang-Ik;Kim, Kyung-Woong
    • Tribology and Lubricants
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    • v.29 no.3
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    • pp.149-159
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    • 2013
  • In this research, the lubrication characteristics of spool valves with various cross-sectional groove shapes were studied. The validity of using the Reynolds equation for the analysis of spool valves with various groove shapes was also investigated. The cross-sectional shapes for the grooves included a triangle, square, and U shape. The characteristics of the flow in the groove were investigated using streamlines. When the number of grooves was increased, the difference between the results obtained from the Reynolds equation and those obtained from the Navier-Stokes equation increased according to the groove shape. Thus, it was found that the Navier-Stokes equation should be used to investigate the lubrication characteristics of the spool valves in those cases. Moreover, in the case where the cross section of the groove was U-shaped, the groove prevented the small eddy current from occurring in the groove. Therefore, the lateral force and friction force of the spool valve with the U-shaped groove were lower than those of the spool valves with other groove shapes.

Analysis of X-ray image Qualities -accuracy of shape and clearness of image using X-ray digital tomosynthesis (디지털 영상 합성에 의한 X선 단층 영상의 형상 정확도와 선명도 분석)

  • Roh, Yeong-Jun;Cho, Hyung-Suck;Kim, Hyeong-Cheol;Kim, Sung-Kwon
    • Journal of Institute of Control, Robotics and Systems
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    • v.5 no.5
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    • pp.558-567
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    • 1999
  • X-ray laminography and DT(digital tomosynthesis) that can form a cross-sectional image of 3-D objects promis to be good solutions for inspecting interior defects of industrial products. DT is a kind of laminography technique and the difference is in the fact that it synthesizes the several projected images by use of the digitized memory and computation. The quality of images acquired from the DT system varies according to image synthesizing methods, the number of images used in image synthesizing, and X-ray projection angles. In this paper, a new image synthesizing method named 'log-root method' is proposed to get clear and accurate cross-sectional images, which can reduce both artifact and blurring generated by materials out of focal plane. To evaluate the quality of cross-sectional images, two evaluating criteria : (1) shape accuracy and (2) clearness of the cross-sectional images are defined. Based on these criteria, a series of simulations are performed, and the results show the superiority of the new synthesizing method over the existing ones such as averaging and minimum methods.

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Heat transfer and pressure drop with the turbulence promoter in a vertical PCB Channel (난류 발생기의 형상에 따른 수직 PCB채널에서의 열전달 및 압력손실 변화)

  • Park, Chan-U;Jang, Seung-Il;Jeong, Jong-Su;Nam, Pyeong-U
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.20 no.7
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    • pp.2277-2288
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    • 1996
  • This study was performed to analyze the cooling effect of heated ribs which are frequently used for cooling of electronic parts, using the numerical method. To prevent the excessive pressure drop due to turbulence promoters for the enhancement of heat transfer rate especially, the effect of the angle of turbulence promoter was investigated by the numerical analysis. Heat transfer rate with turbulence promoters with rectangular cross-section increased by 13% in average, but the coefficient of pressure drop increased by 1.68 times than that without them. In the present study, triangular cross-sectional shape turbulence promoters were suggested and numerically tested. Pressure drop of turbulence promoter with the 30 degree triangular cross-sectional shape decreased by 30% from that of rectangular cross-section promoters while heat transfer rate was almost the same. While with 4 turbulence promoters, the heat transfer rate increased by 21%, the pressure drop increased 4 times. It means that the higher capacity of cooling fan should be needed. With the triangular cross-sectional shape, the size of vortex region at the rear of promoters became considerably smaller, so pressure drop became smaller. The effect of the change of cross-sectional shape was not found in the flow pattern near the ribs, so that heat transfer characteristics in the ribs were not changed.

Study on the Irregular Shape Rolling Process (비대칭 형상 압연 공정에 대한 연구)

  • 김용철;김동진;김병민
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 1999.08a
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    • pp.98-106
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    • 1999
  • In this study cold rolling process for the irregular cross-sectional shape has been investigated. The product analyzed in present study is the steel cutter, which is frequently used to cut the desired shape on leather. Because steel cutter always has a irregular cross-section, after rolling process the workpiece is severely bended to every direction. The bending of the workpiece affects the processed performed after rolling such as heat treatment and grinding, then that of the workpiece becomes more severe. In this study, therefore, to prevent the bending of the workpiece to the left and right sides. rigid-plastic finite element method has been utilized and in order to find optimal roll geometry rapidly, one dimensional equal interval search technique has been also introduced. By using both rigid plastic finite element method and optimum technique, cold rolling process for the irregular cross-sectional shape has been successfully investigated.

Study on Vibration Characteristics in terms of Airfoil Cross-Sectional Shape by Using Co-rotational Plane Beam-Transient analysis (Co-rotational Plane beam-Transient analysis를 이용한 에어포일 단면 형상 변화에 따른 진동특성 연구)

  • Kim, Se-Ill;Kim, Yong-Se;Park, Chul-Woo;Shin, SangJoon
    • Proceeding of EDISON Challenge
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    • 2016.03a
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    • pp.203-208
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    • 2016
  • In this paper, vibration characteristics in terms of the airfoil cross-sectional shape was examined by using the EDISON co-rotational plane beam-transient analysis. Assuming aircraft wing as a cantilevered beam with a constant cross-sectional shape, natural frequencies of each airfoil shape was compared while varying airfoil maximum thickness and maximum camber length, using Fast Fourier Transformation(FFT). When the airfoil maximum thickness was varied, natural frequency showed peak value at 18% chord, and decreased afterwards. When the airfoil maximum camber length was varied, natural frequency either increased or decreased at 6% chord, while at 8% the natural frequency showed its maximum. Applying such trends to B-737 wing airfoil, an improved B-737_mod airfoil shape was obtained with regard to the vibration characteristics.

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Structural Performance of Shearwall with Sectional Shape in Wall-type Apartment Buildings (단면현상에 따른 벽식구조 전단벽의 구조성능 평가)

  • 한상환;오영훈;오창학;이리형
    • Journal of the Korea Concrete Institute
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    • v.12 no.4
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    • pp.3-14
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    • 2000
  • Structural performance of the walls subjected to lateral load reversals depends on various parameters such as loading history, sectional shape, reinforcement, lateral confinement, aspect ratio, axial compression, etc. Thus, the performance of the shearwall for wall-type apartment should be evaluated properly considering above parameters. This study investigates the effect of sectional shape on the structural performance of the wall. Sectional shape of the specimen is rectangular, barbell and T. Based on this experimental results, all specimens behaved as ductile fashion and failed by concrete crushing of the compression zone. Deformation index of those specimens evaluated better than 3 of ductility ratio, and 1.5% of deformability specified by seismic provision. Moreover, the performance of the rectangular shaped specimen, whose compression zone was confined with U-bar and cross tie, was as good as the barbell shaped specimen. Therefore, if we considered construction practice such as workmanship and detailing, shearwall with rectangular section may be more economical lateral load resisting system.