• Title/Summary/Keyword: different shapes

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A Microscopic Study of the Bursa Copulatrix of Gonepteryx (Lepidoptera: Pieridae) (Gonepteryx속(인시목: 흰나비과) 교미낭의 미세구조에 관한 비교분석)

  • Cheong, Seon-Woo;Lee, Chang-Eon;Kim, Hoon-Soo
    • Animal Systematics, Evolution and Diversity
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    • no.nspc3
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    • pp.121-128
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    • 1992
  • Bursae copulatrix of six species of Gonepteryx were morphologically compared using a steroscopic microscope and a scaning electron microscope. As other genera of Pieridae, appendix bursae were developed in this genus and the shapes of the bursae copulatrix were different to species. However, shapes of signa were stable and were not distinct to species. On innersurfaces around ribbon-like signa, many folds were developed and most of inner-surface processes were widely distributed on the oppostie side of signa. Most of innersurface processes were spindle-like and basal ridges were developed. G. aspasia and G. taiwana were recognized as the most similar species in Gonepteryx considering shapes of bursae copulatrix and the condition of innersurface processes.

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A Study of the Shearing Force as a Function Trim Punch Shape and Shearing Angle (트리밍펀치 형상과 전단 각에 따른 전단하중 특성에 관한 연구)

  • Yoo, C.K.;Won, S.T.
    • Transactions of Materials Processing
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    • v.24 no.2
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    • pp.77-82
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    • 2015
  • By investigating the practical use of trim punch configurations for shearing of vehicle panels, the current study first reviews the shearing angle as part of the shearing die design. Based on this review, four different types of trim punch shapes (i.e., horizontal, slope, convex, and concave type) and shearing angles(i.e., 0.76°, 1.53°, 2.29°, 3.05°, 3.81°) were investigated. In order to conduct shearing experiments, four types of trim punch dies were made. The four trim punch dies were tested under various conditions. The experiments used the four trim punch shapes and the five shearing angles. The shearing force varied by shape and decreased from horizontal, slope, convex, to concave for the same shearing angle. The magnitude of shearing force showed differences between the convex and the concave shapes due to the influence of constrained shearing versus free shearing. The test results showed that compared to the horizontal trim punch shearing force, the decrease of the slope, convex, and concave shearing forces were 22.6% to 60.4%. Based on the results, a pad pressure of over 30% is suggested when designing a shearing die.

The Research on the Body Type Comparison between the Koreans Living in China and the Ones in Korea - Focused on Male in Their Twenties - (중국 및 국내 거주 한국인의 체형 비교 연구 -20대 남성을 중심으로-)

  • 석혜정;임순
    • Journal of the Korean Society of Clothing and Textiles
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    • v.28 no.910
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    • pp.1219-1230
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    • 2004
  • This study was conducted to compare the physical shapes of Korean males in their 20s between those residing in Yenbien, China and those living in Korea. Measurements were checked fur 57 items on 167 Korean male residents in Yenbien, China and 295 Korean male residents in Seoul and the other large cities around it. The conclusions are as follows: 1. The comparison of 58 items in physical measurements of Korean male residents in China and those in Korea showed differences in 49 items. Korean male residents in China had the smaller physical shapes short in limbs and height. 2. The comparison of the factor analysis results for physical measurements did not reveal big differences. In terms of the contribution of variables, however, obesity played an exceptionally large role fur Korean residents in China, while the importance of obesity and vertical length were similar for those in Korea. 3. The comparison of the physical shapes according to the grouping resulted in three types each for both groups, with different features for individual types. Korean residents in China were grouped according to the obesity factor rather than the changes in height, while those in Korea were classified according to both vertical length and obesity.

Statistical Analysis of 3D Volume of Red Blood Cells with Different Shapes via Digital Holographic Microscopy

  • Yi, Faliu;Lee, Chung-Ghiu;Moon, In-Kyu
    • Journal of the Optical Society of Korea
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    • v.16 no.2
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    • pp.115-120
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    • 2012
  • In this paper, we present a method to automatically quantify the three-dimensional (3D) volume of red blood cells (RBCs) using off-axis digital holographic microscopy. The RBCs digital holograms are recorded via a CCD camera using an off-axis interferometry setup. The RBCs' phase image is reconstructed from the recorded off-axis digital hologram by a computational reconstruction algorithm. The watershed segmentation algorithm is applied to the reconstructed phase image to remove background parts and obtain clear targets in the phase image with many single RBCs. After segmenting the reconstructed RBCs' phase image, all single RBCs are extracted, and the 3D volume of each single RBC is then measured with the surface area and the phase values of the corresponding RBC. In order to demonstrate the feasibility of the proposed method to automatically calculate the 3D volume of RBC, two typical shapes of RBCs, i.e., stomatocyte/discocyte, are tested via experiments. Statistical distributions of 3D volume for each class of RBC are generated by using our algorithm. Statistical hypothesis testing is conducted to investigate the difference between the statistical distributions for the two typical shapes of RBCs. Our experimental results illustrate that our study opens the possibility of automated quantitative analysis of 3D volume in various types of RBCs.

Grouping Algorithm for Custom-tailored Products (주문헝제품의 생산을 위한 집합화 알고리즘의 개발)

  • 김승엽;이건우
    • Korean Journal of Computational Design and Engineering
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    • v.7 no.2
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    • pp.131-139
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    • 2002
  • Custom-tailored products always vary their sizes and shapes to satisfy the customers' tastes and requirements but they have to be fabricated as fast as possible when ordered. One way to solve this problem is to prepare several representative products in advance and each custom-tailored product is generated by machining the closest representative product. To realize this approach, it would be necessary to be able to group the products into several groups each of which has a representative product. Once the similar products are identified to be grouped, the representative shape can be generated such that all the products in the group can be made by machining the representative product. The custom-tailored products considered in this work have similar shapes but different sizes. Since these products have free surfaces, that are hard to be compared, their convex hulls are used for the grouping. Among all the products to be grouped, one product is chosen as a base shape. The shape and overall similarity values between the base shape and the remaining shapes are calculated as their convex hulls are rotated virtually. By calculating these similarity values at each rotation, the optimal alignment of the reference shape with respect to the base shape is determined. Overall similarity value at this optimal alignment is used as a measure for grouping. A prototype system based on the proposed methodology has been implemented and used to group the shoe-lasts for custom-tailored shoes.

The Analysis of Oxidization Characteristics according to the shapes of RCD contacts (RCD 접점형태에 따른 산화특성 분석)

  • Kim, Dong-Woo;Kim, Hyang-Kon;Gil, Hyoung-Jun;Han, Woon-Kim;Choi, Chung-Seog
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.07a
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    • pp.576-577
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    • 2005
  • In this paper, the oxidization characteristics were analyzed according to the shapes of Residual Current Protective Device(RCD) contacts. RCD is an electrical safety device specially designed to immediately switch the electricity off when electric leakage is detected at a level harmful to a person using electrical equipment. The shapes of RCD contacts are a little bit different according to the models. When RCD is turned on, stationary and moving contact do not fit together. So, it can cause the increase of contact resistance. To discover the deterioration characteristics of RCD contacts by switching repetition, the contacts were analyzed by stereo microscope, Scanning Electron Microscope(SEM) and Energy Dispersive X-ray Spectrometer(EDS).

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Experimental shear strength evaluation of perfobond shear connector with various hole shapes

  • Zheng, Shuangjie;Zhao, Chen;Liu, Yuqing
    • Structural Engineering and Mechanics
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    • v.67 no.2
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    • pp.131-142
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    • 2018
  • The perfobond connector, composed of a steel plate with a number of holes, serves as a certain type of shear connector in steel and concrete composite structures. Depending on limits in hole distances and rib heights, various hole shapes including circular-hole and long-hole are alternatives for perfobond connectors. This study presented the results of tests performed on 72 push-out specimens with perfobond connectors. The purpose was to evaluate the shear strength of perfobond connectors with circular-hole and long-hole. The effects of various parameters were investigated, including the hole diameter, the hole length, the hole height, the concrete strength, the existence, diameter and strength of rebar in the hole, the thickness, height and distance of perfobond ribs, and the thickness of concrete slabs. On the basis of 132 push-out test results in references and in this study, an analytical model was proposed by regression analysis to predict the shear strength of perfobond connectors. The proposed equation agreed reasonably well with the experimental results of perfobond connectors with different hole shapes.

A Study on the Basic Shape of an MF Evaporator (MF증발기 기초 형상 설계에 관한 연구)

  • Park, Yong-Seok;Seong, Hong-Seok;Suh, Jeong-Se
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.18 no.6
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    • pp.39-44
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    • 2019
  • The evaporator is a key driver of an air conditioning system's efficiency. In this study, we study methods of maximizing the efficiency of a Massey Ferguson (MF) evaporator by measuring how the cooling performance of different shapes vary with temperature. We varied the tube insertion depth as well as the shape of the evaporator's header and tube. When we compare header shapes of "D", "Ellipse", and "Quadrangle" types, we find that the elliptical header creates the smallest pressure loss and the highest temperature difference. Between tube shapes of "Rectangular", "Projection", and "Circular" types, the "Projection" type tube creates the most temperature difference. We also investigated the depth of tube insertion in the header and find that tube insertion of 5 - 10 mm is feasible; we selected the depths of 5, 7, and 10 mm since they corresponded to approximately 30%, 50%, and 70% of the total width of the header. The tube insertion test demonstrated that a tube insertion depth of 7 mm creates the least pressure loss and the highest temperature difference. In conclusion, the optimal evaporator design uses an "Ellipse" type header, "Projection" type tube, and a tube insertion depth between 30 and 50% of the header width.

Molecular Dynamics Simulation to compare Turbine Rotational Power based on Nozzle Shapes (노즐 형상에 따른 터빈 축동력 형성 비교를 위한 분자동력학 시뮬레이션)

  • Kim, Su-Hee
    • The Journal of the Korea institute of electronic communication sciences
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    • v.14 no.2
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    • pp.425-432
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    • 2019
  • Molecular dynamics simulations were carried out to analyze the impact on turbine rotational power based on nozzle shapes. y varying two parameters, turbine rotational velocity w and initial velocities ($V_x,V_y$) for generating molecules, turbine rotation velocities of molecules in turbine entrance arc region and turbine exit arc region were calculated. Average momentums were calculated over two regions, respectively and the differences (AMD) were compared and analyzed. The optimal range of w values to enhance AMD was investigated over 4 different nozzle shapes used, and an excellent nozzle shape to achieve more turbine rotational power was drawn.

A Study on the Requirements for the Development of Side Mould for FCP(Free-form Concrete Panel) Manufacturing Equipment (FCP(Free-form Concrete Panel)생산 장비용 측면 거푸집 개발을 위한 요구사항 분석연구)

  • Jeong, Kyeong-Tae;Yun, Ji-Yeong;Youn, Jong-Yeong;Lee, Donghoon
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2020.11a
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    • pp.12-13
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    • 2020
  • Free-form buildings usually have large curved shapes on the outside. In order to construct this curved shape, the exterior of the building must be divided into easy-to-manufacture shapes, and the segmented panel is called the FCP(Free-form Concrete Panel). These FCPs have different shapes and cannot reuse molds. To solve these problems, the researchers developed FCP manufacturing equipment to manufacture a mould of FCP. However, the developed equipment alone cannot completely manufacture FCP's mould. This is because there is no mould to implement side of FCP. Therefore, it is necessary to develop a side form of FCP that can be applied to FCP manufacturing equipment. To this end, this study analyzes the basic requirements that side mould should have before developing side mould.

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