• 제목/요약/키워드: rectangle

검색결과 484건 처리시간 0.024초

NURB 곡면을 이용한 일반 3차원 전계최적화 (Field Optimization Using NURB Surface in 3-Dimensional Space)

  • 이병윤;김응식;박종근
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1991년도 추계학술대회 논문집 학회본부
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    • pp.67-70
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    • 1991
  • When analyzing field or optimizing the shape of electrode in three dimensional space by using the surface charge method, we need to divide finely the surface of electrode into surface element like triangle or rectangle. In this case, there exist any variables in field analysis or field optimization. In particular, smoothness on the surface of optimized shape is not good. Recently, A paper is published where introducing NURB curve to field analysis and field optimization about two dimensional space model and axial symmetric three dimensional space model results in reduced variables, enhenced accuracy and improved smoothness. NURB curve has some useful properties like continuity, controllability and locality. Therefore in this paper, in order to improve the demerits of the established optimization method for three dimensional space models, the NURB surface that has same properties in common with NURB curve is used to analyze and optimize simple model.

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전자회로 도면관리를 위한 벡터화와 회로 기호의 인식 (The vectorization and recognition of circuit symbols for electronic circuit drawing management)

  • 백영묵;석종원;진성일;황찬식
    • 전자공학회논문지B
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    • 제33B권3호
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    • pp.176-185
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    • 1996
  • Transformin the huge size of drawings into a suitable format for CAD system and recognizng the contents of drawings are the major concerans in the automated analysis of engineering drawings. This paper proposes some methods for text/graphics separation, symbol extraction, vectorization and symbol recognition with the object of applying them to electronic cirucit drawings. We use MBR (Minimum bounding rectangle) and size of isolated region on the drawings for separating text and graphic regions. Characteristics parameters such as the number of pixels, the length of circular constant and the degree of round shape are used for extracting loop symbols and geometric structures for non-loop symbols. To recognize symbols, nearest netighbor between FD (foruier descriptor) of extractd symbols and these of classification reference symbols is used. Experimental results show that the proposed method can generate compact vector representation of extracted symbols and perform the scale change and rotation of extracted symbol using symbol vectorization. Also we achieve an efficient searching of circuit drawings.

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1차원 표면유동의 정량화에 따른 직사각형 용기내의 정상유동 해석 (Analysis of Steady Flows in a Rectangular Container with a Characterization of the Free Surface by One-Dimensional Motion)

  • 변민수;서용권
    • 한국해양공학회:학술대회논문집
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    • 한국해양공학회 2001년도 추계학술대회 논문집
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    • pp.227-231
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    • 2001
  • Analysis of two-dimensional unsteady flows with a free surface in a rectangular container subject to a linear reciprocating force is performed by numerical and experimental methods. FVM is used for the numerical computation of the two-dimensional flows. We consider the surface tension as well as the viscous/elastic properties of the free surface. One-dimensional analysis as well as experiment is used in establishing the free surface properties. The steady recirculatory flow is visualized by a laser sheet. It is shown that the one-dimensional analysis provides useful informations associated with the free surface properties.

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점진적 롤 성형 공정을 이용한 이중 곡률을 갖는 일반적인 사각형 시편의 성형 방법 (Forming Method to Manufacture a Doubly Curved General Quadrilateral Sheet Metal Using the Incremental Roll Forming Process)

  • 윤석준;양동열
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2005년도 춘계학술대회 논문집
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    • pp.978-981
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    • 2005
  • In order to manufacture a doubly curved sheet metal effectively, a flexible incremental roll forming process has been developed by adopting the advantages of the incremental forming process and the roll forming process by combining inherent flexibility of the incremental forming process and continuous deformation of the roll forming process. The forming method has been further enhanced to form general quadrilateral blanks (including a square, a rectangle, a symmetrical trapezoid and an asymmetrical trapezoid, etc.) into doubly curved shapes by controlling the forming paths developed by various experiments.

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로봇과 인간의 상호작용을 위한 얼굴 표정 인식 및 얼굴 표정 생성 기법 (Recognition and Generation of Facial Expression for Human-Robot Interaction)

  • 정성욱;김도윤;정명진;김도형
    • 제어로봇시스템학회논문지
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    • 제12권3호
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    • pp.255-263
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    • 2006
  • In the last decade, face analysis, e.g. face detection, face recognition, facial expression recognition, is a very lively and expanding research field. As computer animated agents and robots bring a social dimension to human computer interaction, interest in this research field is increasing rapidly. In this paper, we introduce an artificial emotion mimic system which can recognize human facial expressions and also generate the recognized facial expression. In order to recognize human facial expression in real-time, we propose a facial expression classification method that is performed by weak classifiers obtained by using new rectangular feature types. In addition, we make the artificial facial expression using the developed robotic system based on biological observation. Finally, experimental results of facial expression recognition and generation are shown for the validity of our robotic system.

콘크리트댐 저면 침수에 관한 고찰 (A Study on Seepage of the Concrete Dam base)

  • 정형식;신방웅
    • 한국농공학회지
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    • 제18권1호
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    • pp.4071-4078
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    • 1976
  • The authors analyzed the seepage by means of the following mathmatical solutions of the Laplace Equations on the given boundary conditions. The boundaries of the flow region are of two types i) impervious boundaries (${\Phi}$=constant), and ii) reservoir boundaries (${\Phi}$=constant). The corresponding w plane, bounding the flow region, is the rectangle in Fig. 8-a. As the z plane and w plane are both polygons, by means of the Schwarz-Christoffel transformation the flow region in each of these planes can be mapped con for mally onto the same half of an auxiliary t plane, there by yielding, say, the functions z=f1(t) and w=f2(t). Then, either by eliminating the variable t or by using t as a parameter, the function w=f(z) can be established.

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사각형 용기내의 비정상 이중확산유동에 관한 실험적 연구 (Experimenal Study on Unsteady Double-Diffusive Convection in a Rectangle)

  • 홍남호;김창수;현명택
    • 한국해양공학회지
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    • 제8권1호
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    • pp.105-113
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    • 1994
  • Double-diffusive convection induced by simultaneously-imposed lateral temperature and concentration gradients in a rectangular enclosure with aspect retio, 2.0 has been studied experimentally for adiabatic and isothermal horizontal boundary conditions. Visual observations show two distinct flow structures depending on the buoyancy ratio. The unicell flow structure is observed for a lower buoyancy ratio while the layered flow structure appears for a higher buoyancy ratio. There exists an unstable flow regime between two buoyancy ratios.

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PAI 유/무기 하이브리드코일의 곡률변화에 따른 AC 및 DC 절연파괴 특성 (Insulation Breakdown Properties of AC and DC according to Curvature Variation of PAI Organic/Inorganic Hybrid Coils)

  • 박재준
    • 전기학회논문지
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    • 제65권10호
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    • pp.1721-1726
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    • 2016
  • 4-types of coils were prepared by coating with polyamideimide (PAI) organic/inorganic hybrid. One type was made with original PAI vanish and the other 3-types were made of double layers, that was to say, high flexural PAI layer and high anti-corona PAI/nanosilica (15 wt%) layer. Drying temperature (T/D) were $220^{\circ}C$, $240^{\circ}C$, and $260^{\circ}C$, respectively and rectangular type coil for high-voltage rotating machine was used. DC and AC electrical breakdown tests were carried out in order to study the insulation properties according to T/D temperature and coil curvature (5, 15, and $25mm{\Phi}$). As the curvature increased, electrical breakdown voltage decreased and as T/D temperature decreased, electrical breakdown voltage increased.

그래픽스 전용 메모리 설계 (Special Memory Design for Graphics)

  • 김성진;문상호
    • 한국멀티미디어학회논문지
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    • 제2권1호
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    • pp.80-88
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    • 1999
  • 본 논문에서는 컴퓨터 그래픽스 연산의 메모리 액세스 속도를 개선하는 새로운 메모리 구조를 갖는 그래픽스 전용 메모리(SMGRA, Special Memory for GRAphics)를 제안한다. 제안된 그래픽스 전용 메모리는 사각형 영역의 화소를 동시에 처리할수 있는 Whelan이 제안한 장방형 어레이 메모리 구조를개선하여 주소디코딩시 간을 줄여주고 멀티플렉싱 기법을 사용하여 주소핀 수를 1/2로 줄인다 또한, 그래픽스 전용 메모리는 간단한 연산 로직을 가지므로 3차원 그래픽스 처리시 요구되는 읽기-수정-쓰기 메모리 사이클을 쓰기 메모리 사이클 로 대체하므로 프레임 버퍼 액세스 속도를 개선한다.

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오면체 모양 절제법을 이용한 유두축소 (Nipple Reduction with a Pentahedral Excision Technique)

  • 홍윤기;심형보
    • Archives of Plastic Surgery
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    • 제36권3호
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    • pp.327-332
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    • 2009
  • Purpose: Several methods of the nipple reduction have been reported. However, the methods described previously are difficult or have some demerits. This study proposes a simple technique for reduction of the nipple height as well as diameter. Methods: The purposed nipple height is marked. A pentahedral design of excision was marked around the nipple. Local anesthetic solution was infiltrated and a 4 - 0 Nylon traction suture was applied at the nipple apex. Excision of the nipple inside both two triangles and a rectangle was made. Remaining two flaps were approximated using 5 - 0 Nylon simple interrupted sutures. However, a part of wound closure was not done in the central area of the nipple. Results: 83 patients(166 nipples) underwent this procedure from December 1999 to December 2008. Follow up ranged from 6 months to 2 years with a mean of 10 months. 78 patients were female and 5 patients were male. No major complication occurred and remaining scars were very inconspicuous. Conclusion: This simple technique has the advantage of nipple reduction in both height and diameter, and provides good aesthetic outcomes.