• Title/Summary/Keyword: Shape Factor

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Shape Optimization of a Thomson Coil Actuator for Fast Response Using Topology Modification

  • Li, Wei;Koh, Chang-Seop
    • Journal of Electrical Engineering and Technology
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    • v.7 no.1
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    • pp.58-63
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    • 2012
  • The shape optimization of a Thomson coil actuator used in an arc eliminator is done for fast response by adopting topology modification method. The displacement of the plate in a fixed calculation time is taken as the objective function. The objective function and contribution factor are calculated by using an adaptive equivalent circuit method which has been proved accurate and efficient. Both shape optimization and performance analysis are accomplished based on the segmentation of plate. Through the refinement of the sensitive segments a precise optimal plate shape can be obtained. The effectiveness of the proposed method is proved by the comparison of results before and after the shape optimization.

A Basic Study on Analysis of the Impact of Building Shape on Safety Accidents (건물의 형상이 안전사고에 미치는 영향분석에 관한 기초연구)

  • Son, Seunghyun;Kim, Ji-Myung;Ahn, Sungjin;Han, Bumjin;Na, Youngju;Kim, Taehui
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2022.04a
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    • pp.27-28
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    • 2022
  • There is a limit to preventing various types of safety accidents in advance at construction sites. Even for buildings of the same total floor area, it is expected that the more complex the building shape or the higher the number of floors, the higher the probability of a safety accident. Therefore, it is necessary to analyze the effect of the shape of a building on safety accidents using safety accident data generated during actual construction. The purpose of this study is to analyze the impact of building shape on safety accidents. As a result, the R2 value of shape factor and safety accident was 0.901, and the R2 value of construction difficulty and safety accident was 0.944. In the future, the results of this study will be used as basic data for improving safety management related systems.

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Upper Body Type Analysis for Middle-aged Women Aged 50-69 Years (50-69세의 중장년 성인여성을 위한 상반신 체형분석)

  • Lee, Jin Hee;Kim, Eun Kyong
    • Journal of the Korea Fashion and Costume Design Association
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    • v.24 no.3
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    • pp.49-61
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    • 2022
  • This study aims to provide upper body shape information by analyzing the measurement data of middle-aged women aged 50-69, including baby boomers, whose economic power and activity have improved compared to the previous generations. In order to provide accurate upper body shape information by analyzing the body type using the 8th Size Korea measurement data, body shapes were classified through factor and cluster analysis using 75 direct measurement items. Upper body type was classified according to the factors, and the associated characteristics were analyzed. As a result of the comparative analysis of the upper body measurements from the 4th to the 8th Size Korea measurement, it was found that in the height item, both the waist height and the hip height increased, making the overall height greater and the leg length longer. The body circumference items tended to increase, but were found to decrease significantly in the 8th Size Korea (2021) measurement. Middle-aged women were classified using five factors. Factor 1 was the upper body obesity factor, and Factor 2 was the trunk vertical factor. Factor 3 was the width of the back shoulder, Factor 4 was the vertical factor behind the back, and Factor 5 was the length factor of the front garment composition. Middle-aged women were classified into four body types through cluster analysis. Type 1 is relatively small and skinny, Type 2 has the most obese upper body and developed back shoulders, and Type 3 is skinny and has a long back and short front. In Type 4, the upper body was relatively long and the shoulders were narrow.

Detemination of Dynamic Stress Intensity Factor of Brittle Materials under Impact Loading (충격하중을 받는 취성재료의 동적응력확대계수 결정)

  • 이억섭;이찬석
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1993.10a
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    • pp.381-386
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    • 1993
  • This paper describes the dynamic fracture behavior of brittle materials under impact loading by using INSAMCR program with instrumented charpy test machine. To calculate the Dynamic Stress Intensity Factor The finite element analysis methods program, INSAMCR, was used. Dynamic fracture characteristic was researched to verify a relationship between Dynamic Stress Intensity Factor and crack tip propagation velocity in WC-6%Co. The relationship between Dynamic Stress Intensity Factor and crack tip velocity revealed typical .GAMMA. shape. INSAMCR was run to verify experimental results in WC-6%Co and shows a good coincidence.

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A Study on the Lower Body Somatotype of the 20s' Women (20대 여성의 하반신 체형 관찰)

  • Lee, Youn-Soon;Ryu, Ji-Hyun
    • Journal of the Korea Fashion and Costume Design Association
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    • v.9 no.1
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    • pp.161-171
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    • 2007
  • The purpose of this study was to classify the lower body of the lost women and to investigate the three-dimensional characteristics of each lower body somatotype of them. The subject were ninety seven women whose. age were twenties and whose height and bust girth were in the range of mean$\pm1\delta$ of typical body size of twenties' Korean women. The forty one variables of their lower body were measured by Martin's Anthropometric Instrument. And they were analyzed for mean, standard deviations factor analysis, and cluster analysis. In the second phase of analysis, the three participants were re-selected in each type were measured by Sliding Guage and analyzed their lower body somatotype. The results were as follows; The components of lower body of 20s' women were extracted with 7 factors through factor analysis and orthogonal rotation by the method of Varimax. The rate of the cumulative contribution was 84.1% the first factor was the thickness of lower body, the second factor was the vertical size of lower body the third factor was the front shape of hip, the forth factor was the vertical size of hip, the fifth factor was the shape of abdomen, the six factor was the flat-ratio of waist and the seventh factor was flat-ratio of hip. The somatotype of 20's women's lower body can be classified into 3 types. Type 1 is the standard somatotype of 20's women's lower body and the 34.0% of the participants in the study was categorized into type 1. Type 2 is a short and corpulency type with protruded abdomen and hip and the 29.9% of the participants in the study was categorized into type 2. And the type 3 is a tall and thin type with plat abdomen and hip and the 37.1% of the participants was categorized into type 3.

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Development of a Surface Shape for the Heat Transfer Enhancement and Reduction of Pressure Loss in an Internal Cooling Passage (내부 냉각유로에서 열전달 강화와 압력손실 감소를 위한 표면 형상체의 개발)

  • Doo, Jeong-Hoon;Yoon, Hyun-Sik;Ha, Man-Yeong
    • Proceedings of the KSME Conference
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    • 2008.11b
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    • pp.2465-2470
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    • 2008
  • A new surface shape of an internal cooling passage which largely reduces the pressure drop and enhances the surface heat transfer is proposed in the present study. The surface shape of the cooling passage is consisted of the concave dimple and the riblet inside the dimple which is protruded along the stream-wise direction. Direct Numerical Simulation (DNS) for the fully developed turbulent flow and thermal fields in the cooling passage is conducted. The Numerical simulations for the 5 different surface shapes are conducted at the Reynolds number of 2800 based on the mean bulk velocity and channel height and Prandtl number of 0.71. The driving pressure gradient is adjusted to keep a constant mass flow rate in the x direction. The thermo-aerodynamic performance for the 5 different cases used in the present study was assessed in terms of the drag, Nusselt number, Fanning friction factor, Volume and Area goodness factor in the cooling passage. The value of maximum ratio of drag reduction is -22.86 [%], and the value of maximum ratio of Nusselt number augmentation is 7.05 [%] when the riblet angle is $60^{\circ}$ (Case5). The remarkable point is that the ratio of Nusselt number augmentation has the positive value for the surface shapes which have over $45^{\circ}$ of the riblet angle. The maximum Volume and Area goodness factor are obtained when the riblet angle is $60^{\circ}$ (Case5).

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A Study on The Prediction of Workpiece Shape of The Electrochemical Machining by Boundary Element Method (경계요소법에 의한 전해가공물의 형상예측에 관한 연구)

  • 강대철;양재봉;김헌영;전병희
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2003.05a
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    • pp.443-447
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    • 2003
  • The BEM (Boundary Element Method) is a computational technique for the approximate solution of problems in continuum mechanics. In the BEM both volume and surface integrals transformed into boundary integral equations. So, we applied the ECM (Electrochemical Machining) process to boundary problem, because our focus is only deformed shape. The ECM process is modeled as a two-dimensional problem assuming constant properties of electrolyte, and an incremental formulation is used with automatic mesh regeneration. As a result the final shape is roughly agreed with experimental shape. But, it has an error of exact shape, because a chemically factor is not considered

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