• Title/Summary/Keyword: Irregular shape

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Parallel Gripper Mechanism (병렬형 그리퍼 메커니즘)

  • Cho, Kuk-Hoon;Lee, Jae-Hoon;Yi, Byung-Ju;Kim, Whee-Kuk
    • Journal of the Korean Society for Precision Engineering
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    • v.16 no.11
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    • pp.89-97
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    • 1999
  • A new parallel gripper mechanism is proposed in this work. This device has a parallelogrammic platform which can be flexibly folded. Therefore, this mechanism not only can be used to grasp an object having irregular shape or large volume, but also can be used as a micro-positioning device after grasping. Based on the position and kinematic analysis for this mechanism, this mechanism has been developed and the motion performance has been tested to corroborate the effectiveness of this mechanism.

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Apparel Sizing System for Obese Men in There 20s (20대 비만 남성을 위한 의복 사이즈 체계에 관한 연구)

  • Yoon, Ji-Won;Suh, Mi-A
    • The Research Journal of the Costume Culture
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    • v.19 no.3
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    • pp.449-459
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    • 2011
  • The purpose of this study is investigate the feature of the body shape of obese males and to propose a new apparel sizing system considering the body size of obese men through an the analysis of the body measurement of obese men in their twenties as reported in the 'Fifth Korean National Physical Standard Reports'. For this study, a new apparel sizing system for casual wear was proposed for obese men in their twenties after a body measurement of 159 obese men in their 20s with a BMI of 25 and over as reported in the 'Fifth Korean National Physical Standard Reports' conducted by SIZEKOREA. This study sought to investigate the features of obese men's bodies by comparing the body shape between obese men and ordinary men. The result of shows that width, depth and circumference items influencing the width size when producing clothes are larger in the case of an obese body shape than an ordinary body shape, and that the stature, total length, arm length and outside leg length influencing the length size are similar between an obese body shape and an ordinary body shape. Therefore, it was confirmed that an apparel sizing system specializing in clothes for obese customers is required. As a result of this study of the features of body shape, the control dimensions for such an apparel sizing system were determined to be the stature and chest circumference of upper garments and the stature and waist circumference(omphalion) for lower garments. The interval between the sizes was 5cm for the stature and was irregular for the chest and waste circumference. Consequently, 8 sizes were proposed for upper garments and 9 sizes were proposed for lower garments.

Ultrastructural Changes of the Vas Deferens Epithelium by Season in a Slug Incilaria fruhstorferi (산민달팽이(Incilaria fruhstorferi) 수정관 내강 상피조직의 계절에 따른 미세구조적 변화)

  • 장남섭;정계현;한종민
    • The Korean Journal of Zoology
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    • v.39 no.4
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    • pp.400-409
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    • 1996
  • A study on the ultrastructural changes In the epithellum of the vas deferens by season was conducted for the spdng and summer specimens of a slug Incilarfa fruhstoiferl. The vas deferens of the spdng spedmen was muscular tube about 0.4mm in diameter. Its lumen was divided into three flat grooves and the each groove was subdivided into two subbranches. The luminal epithellal celis of the Vas deferens which were irregular In shape showed strong methylenophilla in a double stain of methylene blue and basic fuchsln. The lumen of the vas deferens was filled with components strongly stained by methylene blue. The circular muscle layers surrounding the luminal epithellum of the vas deferens contained numerous granules arranged at regular intervals. The vas deferens of the summer specimen also was a thick muscular tube showing 0.4 mm in diameter. Its lumen was divided into four grooves but, the each of the grooves was not subdivided to form certain branclees unlikely to the spdng spedmen. The lining epfthelium of the lumen was consisted of simple ciliated columnar cells, irregular columnar cells and conical cells. The histological features were quiet different from those of the spring spedmen which showed irregular cell arrangement. According to electron microscopy the epithelium of the vas deferens in the spring specimen was composed of irregular columnar cells which had irregular shaped nuclei. The nuclei of the epitheilal cells were relatively large in comparison to their cytoplasm. The overall electric density of the cytoplasm was relatively high. The lumen of the vas deferens in the summer specimen was lined by a epfthelium with tail ciliated columnar cells and irregular cells. The unclei of the epithellal cells were long ellipsoid or irregular in shape. Both of the cytoplasm and the nuclei were showed low electric density. in consideration with the observable cell organelles were only ndoplasmic reticulum, lysosomes and microtutules, the cell organelles were poorly developed. The apical surfaces of the epithelial cells possessed brush borders with numerous microvilli and cilia with 9+2 arrangement of microtubules. The circular muscle layers surrounding the epithelium are usually thick and the degree of development of the circular muscle layers seems to be even in the both of the spring and summer specimens.

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PREVIEW CONTROL FOR EDGE-FOLLOWING USING ROBOT FORCE CONTROL

  • Yong, Boojoong
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.8 no.1
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    • pp.100-111
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    • 1999
  • This paper resents a discrete-time model of an edge-following with accommodation force control. Since an irregular workpiece shape causes disturbances to the system while following an edge, the use of preview control is proposed to improve the system performance. The preview control employs future information of the workpiece contour shape, and it can be developed by LQ-optimal control principles. This study provides a general method how to utilize the local future information obtained by the finite preview to minimize an optimality criterion evaluated over a problem duration. The force controller is designed based on the preview control scheme, and then implemented on a VME-based computer. Experimental results using an industrial robot show that the preview control system achieves faster tracking speed and better force regulation than the conventional nonpreview control system.

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Densification of Metal Injection Molding Parts Made of Ball Milled W-20%Cu Powders (볼밀링한 W-20wt%Cu 분말로 제조된 금속사출성형 부품의 조밀화)

  • 김순욱;류성수;문인형
    • Journal of Powder Materials
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    • v.7 no.4
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    • pp.228-236
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    • 2000
  • An investigation was carried out on the possibility whether the ball-milling process of low energy could successfully improve the packing density and flowability for MIM application in W-20wt%Cu system. In this study, W-20wt%Cu powder mixture was prepared by ball-milling. W powder was not fractured by low mechanical impact energy used in the present work during the critical ball-milling time, but the ductile Cu powder was easily deformed to the 3 dimensional equiaxed shape, having the particle size similar to that of W powder. The ball-milled mixture of W-20wt%Cu powder had the more homogeneous distribution of each component and the higher amount of powder loading for molding than the simple mixture of W-Cu powder with an irregular shape and a different size. Accordingly, the MIM W(1.75)-20wt%Cu powder compacts were able to be sintered to the relative density of 99% by sintering at $1400^{\circ}C$ for one hour.

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Thermal degradation properties of blue emitting phosphor particles prepared by the spray pyrolysis for PDP (분무열분해공정에서 제조된 PDP용 청색형광체의 열화특성)

  • Kang, Yun-Chan;Lee, Dong-Youl;Park, Hee-Dong
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.07b
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    • pp.1060-1062
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    • 2002
  • Spherical and dense BAM phosphor particles were prepared by spray pyrolysis. The key idea of dense BAM particles is to lead gelation in droplets, which was successfully achieved by using the aluminum polycation as the precursor solution for the spray pyrolysis. The BAM phosphor particles prepared by spraying the aluminum polycation solution have completely spherical shape and dense structure. When directly applied to make phosphor film on the glass by the screen-printing method, the prepared spherical BAM phosphor particles showed better packing density and surface morphology than that of commercial one, which has irregular shape and large particle size. It was also found that the thermal degradation in the photoluminescence intensity for dense and spherical BAM particles was less than that of commercial one.

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Two new species of genus Luffariella (Dictyoceratida: Thorectidae) from Korea

  • Sim, Chung Ja;Lee, Kyung Jin;Kim, Young A
    • Journal of Species Research
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    • v.6 no.2
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    • pp.190-194
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    • 2017
  • Two new species of the genus Luffariella (Dictyoceratida: Thorectidae), L. tubula n. sp. and L. koreana n. sp. were collected from Jeju-do, Korea. These species differ significantly from the previously reported five species in terms of shape and skeletal structure. L. tubula n. sp. has two categories in thickness of secondary fibres which were different from other species. L. koreana n. sp. is very similar to L. variabilis from Tahiti in skeletal structure, but differs in sponge shape with irregular branching and indistinct surface conules. Primary fibres of the two new species are separated from secondary and tertiary fibres.

Estimation of End Milling Depth of Cuts Using the Cutting Force (절삭력을 이용한 엔드밀링 절입깊이 추정)

  • 최종근;양민상
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1997.04a
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    • pp.1033-1037
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    • 1997
  • In the end milling process, the information of axial and depths of cut plays an important role in adaptive control systems for precision machining and tool monitoring systems for unmanned machining. In general, it is not easy to know the depths of cut due to irregular shape of workpieces, inaccurate positioning of them on the table of machine tool and machining error in previous cutting. In addition to, even they are informed, it is difficult to match the individual position of the cutter on the varying shape of the work material. This work suggest an algorithm estimating the depths of cut based on cutting force sigal. The proposed algorithm can be applied in more extensive cutting situations, for example, presence of the tool wear, variation of work material hardness, etc.

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역극성시 금속수지복합체와 세라믹수지복합체의 형상방전가공 특성

  • 우정윤
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 1996.10a
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    • pp.52-57
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    • 1996
  • Conductive Ceramic Matrix Composite(CMC) of TIC/Al2O3 and Metal Matrix Composite (MMC) of SiC/Al were experienced by the die sinking Electrical Discharge Machining(EDM) for different current and duty factor according to negative polarity. Inthis experimental study Material Removal Rate(MRR) maximum surface roughness four point bending stress distribution and Scanning Electron Microscopy(SEM) Photographs were analysed. the higher MRR was obtained for CMC than MMC but slowly decreased around duty factor of 0.67 for MMC and better surface morphology was found CMC than MMC. The SEM photographs of discharge traces for CMC showe uniform shape about 100 to 200${\mu}{\textrm}{m}$ in diameter but MMC showed irregular shape.

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Sonographic Findings of Thyroid Papillary Carcinoma (갑상선 유두암의 초음파 소견)

  • Lee, Jae-Kyo
    • Journal of Yeungnam Medical Science
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    • v.21 no.2
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    • pp.224-230
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    • 2004
  • Background: To determine the various sonographic findings in a papillary carcinoma of the thyroid. Materials and Methods: 48 patients with a proven papillary carcinoma of the thyroid were involved. The sonographic features analyzed were the size, shape, content, margin, internal echo, and calcification pattern. Results: Common sonographic features of a papillary carcinoma include the hypoechoic texture (94%), an ill defined margin (81%), a solid nodule (100%), irregular shape (48%), and microcalcifications (35%), or no calcifications (42%). The uncommon features included a hyperechoic or mixed echo texture, cystic elements, a well defined margin, and a coarse or peripheral calcifications. Conclusion: Ill-defined hypoechoic solid nodule with microcalcification is a characteristic ultrasonographic finding of a thyroid papillary carcinoma.

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