• 제목/요약/키워드: pattern shape

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도로동공 탐지를 위한 지표투과레이더의 신호패턴에 관한 연구 (Signal Pattern Analysis of Ground Penetrating Radar for Detecting Road Cavities)

  • 윤진성;백종은;최연우;최현;이창민
    • 한국도로학회논문집
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    • 제18권6호
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    • pp.61-67
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    • 2016
  • OBJECTIVES : The objective of this study is to detect road cavities using multi-channel 3D ground penetrating radar (GPR) tests owned by the Seoul Metropolitan Government. METHODS : Ground-penetrating radar tests were conducted on 204 road-cavity test sections, and the GPR signal patterns were analyzed to classify signal shape, amplitude, and phase change. RESULTS : The shapes of the GPR signals of road-cavity sections were circular or ellipsoidal in the plane image of the 3D GPR results. However, in the longitudinal or transverse direction, the signals showed mostly unsymmetrical (or symmetrical in some cases) parabolic shapes. The amplitude of the GPR signals reflected from road cavities was stronger than that from other media. No particular pattern of the amplitude was found because of nonuniform medium and utilities nearby. In many cases where road cavities extended to the bottom of the asphalt concrete layer, the signal phase was reversed. However, no reversed signal was found in subbase, subgrade, or deeper locations. CONCLUSIONS : For detecting road cavities, the results of the GPR signal-pattern analysis can be applied. In general, GPR signals on road cavity-sections had unsymmetrical hyperbolic shape, relatively stronger amplitude, and reversed phase. Owing to the uncertainties of underground materials, utilities, and road cavities, GPR signal interpretation was difficult. To perform quantitative analysis for road cavity detection, additional GPR tests and signal pattern analysis need to be conducted.

굽힘공정을 갖는 불규칙형상 박판제품의 블랭킹 및 피어싱용 공정설계 시스템 (An Automated Process Planning System for Blanking or Piercing of Irregular Shaped Sheet Metal Product with Bending Processes)

  • 최재찬;김병민;김철
    • 한국정밀공학회지
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    • 제15권3호
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    • pp.18-23
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    • 1998
  • This paper describes a research work of developing a computer-aided design of blanking and piercing for irregular-shaped sheet metal products. An approach to the CAD system is based on the knowledge-based rules. Knowledge for the CAD system is formulated from plasticity theories, experimental results and the empirical knowledge of field experts. The system has been written in AutoLISP on the AutoCAD with a personal computer and is composed of four main modules, which are input and shape treatment, flat pattern layout, production feasibility check, and strip layout module. Based on knowledge-based rules, the system is designed by considering several factors, such as radius and angle of bend. material and thickness of product, complexities of blank geometry and punch profile, and availability of press. This system is capable of unfolding a formed sheet metal part to give flat pattern and automatically account for the adjustment of bend allowances to match tooling requirements by checking the dimensions and relationships of parts of the folded product. Also this system can carry out a process planning which is obtained from results of irregular shape of product that was successful in production feasibility check module according to flat pattern layout and generate strip layout drawing in graphic forms. The developed system provides its efficiency for flat pattern layout, and strip layout for the irregularly shaped sheet metal products.

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17세기말기-18세기말 프랑스 남자 쥐스또꼬르 유형변화와 패턴제작 연구 (A Study of the Changes in Types of Justaucorps for French Men, and Pattern making from the End of the 17th Century to the End of the 18th Century)

  • 김양희
    • 복식
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    • 제59권8호
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    • pp.49-65
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    • 2009
  • As basic materials in this research, 874 pieces of engraving that recorded the garment produced by diverse authors in the 17-18th century were collected among the collections of male and female garment in the engraving kept by National Library of France and 216 pieces of engraving were classified among them to observe justaucorps as stated in the materials. Since type of justaucorps in the 18th century can be classified by difference in shape and change through the above engraving materials in large quantity and the shape and composition can be compared and analyzed with other materials such as picture, stored garment, written materials without difficulty, the chronology can be composed by single type of justaucorps. Intending to understand the change in composition caused by type classification and pattern making as per analysis of type property of justaucorps, the men's upper garment in France in the 18th century. Checking change in design per from and materials, justaucorps of 1680-1700s was in silhouette where waist in the length above knee was adhered and slightly spread to lower part. In the type of 1710-1750s, waist adhered remarkably and many pleats were made under waist to produce volume of form that spread to lower part like skirt. In the type of 1760-1780s, straight silhouette was attached to whole body and end of front adjustment in slant line turns to rear part. The developmental aspect of construction can be checked by making pattern. Changing the cutting line of body plate to smoothly connect section and to try to adhere to the body, the development of simpler and delicate pattern production technique was confirmed.

자궁경부 종괴형 자궁경부임신의 영상 소견 (Radiologic Findings of Cervical Mass Type Cervical Pregnancy)

  • 조재호
    • Journal of Yeungnam Medical Science
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    • 제22권1호
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    • pp.43-51
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    • 2005
  • 자궁경부 종괴형 자궁경부임신은 빠른 진단과 치료를 요하는 산과적 응급 상황으로 특징적인 초음파 및 MRI 소견을 정확하게 숙지하고 있어야 한다. 특징적인 초음파 소견으로는 혈중 ${\beta}$-HCG 수치가 상승되어 있는 환자에서 자궁경부의 확장, 심하게 불균일한 종괴, 색도플러 검사에서 강한 혈류, 영양막주위 혈류 양상 등이 있다. 특징적인 MRI 소견으로는 자궁경부의 종대, T2-강조영상에서 심하게 불균일한 혼합 신호강도, 가장자리의 저신호강도의 띠, 조기에 강하게 조영증강되는 결절성 부분 등이 있다.

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MCT 가공을 통한 알루미늄 합금의 표면 거칠기와 가공형상에 관한 연구 (A Study on Processing Shape and Surface Roughness of Aluminum Alloy by MCT Processing)

  • 김규태;김원일
    • 한국산업융합학회 논문집
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    • 제16권3호
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    • pp.85-93
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    • 2013
  • The MCT has been most extensively used in the machining. In particular, the ball endmill has been mainly adopted for finishing on the free- form surface. The advancement of CAD/CAM software has made it possible to develop various cutting pattern methods and to create diverse tool routes. Therefore, the current research made an attempt to find the optimal cutting pattern among the seven cutting patterns (i.e., Follow Periphery, Zig, Zig Zag, Concentric Zig, Concentric Zig Zag, Radial Zig, Radial Zig Zag) when aluminium 6000 series were machined by the ball endmill. The optimal pattern was found by comparing different shapes and surface roughness produced by the seven patterns. The current research found that each cutting pattern produced its own unique geometric features on the machined surface. It was found that the Radial Zig cutting pattern produced the lowest roughness on the flat surfaces. The Radial Zig Zag cutting pattern was found to produce the most accurate free-form surface. Finally, the most efficient cutting pattern in terms of machining time turned out to be the Follow Periphery.

주문생산을 위한 자동제도 토르소 원형연구 -20대 여성을 중심으로- (A Study on the Development of Torso Pattern for an Automated Order-based Manufacturing System - focused on women in the twenties -)

  • 황수연;남윤자
    • 대한인간공학회지
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    • 제21권1호
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    • pp.67-80
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    • 2002
  • An efficient torso pattern has been developed to cope with the future trend of order-based, individualized production like the E.C.(Electronic Commerce) in the apparel industry, and to make a database foundation of automatic garment pattern drafting. For this purpose, a non-contact three-dimensional anthropometric measurement system was used to provide a lot of accurate body data for better individual fit, and an automatic pattern drafting system that can easily generate various size patterns and construct a pattern database has been developed too. The subjects of this research were 18 to 24 year-old women whose data had been gathered through the Korean national investigation of anthropometry for industrial standards in 1997 and various body shapes were analyzed by the measurements. And a special software system has been developed to verify the validity of newly proposed drawing rules. The results of sensory evaluation for appearance and moving fitness of the new torso pattern showed a significant improvement in individual fit even for the figures with large deviation from standard shape compared with the results of the traditional one.