• 제목/요약/키워드: surface representation

검색결과 337건 처리시간 0.031초

자유곡면 가공을 위한 CAD/CAM 시스템 (An Integrated System for Computer-Aided Design and Manufacturing of Sculptured Surface)

  • 김광수;최영환
    • 대한산업공학회지
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    • 제17권1호
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    • pp.37-49
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    • 1991
  • This report describes an integrated approach to sculptured surface design and manufacture, and a software package for it on a multi-axis NC milling machine. The integrated software consists of four parts : (1) surface fitting procedure for generating the characteristic polyhedron from 3 dimensional CMM data, (2) surface description for generating the mathematical representation of sculptured surfaces. (3) tool path generation for approximating the surface representation into a sequence of linear cutter paths, and (4) tool control for generating the corresponding joint variable values. This integrated approach is generally applicable to sculptured surface manufacturing where multi-axis milling machines are necessary to produce smooth three-dimensional surfaces.

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X3D를 이용한 WebSD기반 3D Object 표현에 대한 연구 (A Study on the 3D Object Representation based WebSD Using X3D)

  • 이성태;김이선;기우용;이윤배
    • 한국정보통신학회논문지
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    • 제6권4호
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    • pp.632-638
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    • 2002
  • 확장할 수 있는 3D는 멀티미디어와 통합된 방송에 기초한 3D 콘텐츠와 상호 웹의 특징이 되는 소프트웨어의 기준이하고 할 수 있다 그런데, Web3d상에서 다각형의 polygon meshes을 처리하기에는 데이터의 크기나 실제에 적용하기에는 문제가 있다. 본 논문에서는 3차원 객체를 높은 품질로 표현하기 위해서 새로운 framework을 적용한다. 다양하고 자연스러운 형태의 표현을 위해 Web3D 자료형태를 VRML과 XML을 이용하여 처리한다. 3차원 객체의 polygon을 패한 구조를 정의하고 모델링 하여 타당성을 검증한다.

정확한 돌출 형상의 표현을 위한 변위매핑 (Displacement Mapping for the Precise Representation of Protrusion)

  • 유병현;한순흥
    • 한국정보과학회논문지:시스템및이론
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    • 제33권10호
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    • pp.777-788
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    • 2006
  • 물체의 표면에 돌출된 형상을 실시간으로 표현하는 변위매핑 방법에 대하여 설명한다. 기존의 이미지 기반 변위매핑 방법이 기준면에서 함몰된 형상만을 표현할 수 있는 것과 달리, 기준면에서 수직방향으로 돌출된 높이를 표현하여, 표면에서 돌출된 형상의 상세를 실시간으로 표현한다. 또한 폴리곤의 경계부분에서 시점에 따라 수직인 두 개의 면을 추가하여, 기준면의 경계 외부로 초과하는 픽셀의 변위를 표현하였다. 이로써 경계부분의 돌출 형상에 대한 정확한 외곽선을 표현할 수 있다. 제안된 방법은 부드러운 돌출 형상의 표현과 더불어 돌출 형상의 급격한 경사면에 텍스처 정보를 추가하여, 수직 돌출 형상을 포함한 급격한 경사면을 표현할 수 있다. 이 방법은 GPU에서 수행 가능한 픽셀 단위 계산으로 이루어져 실시간으로 가시화가 가능하며, 경계부위의 정확한 외곽선의 표현과 급격한 돌출 형상의 표현이 가능하여, 건물과 같이 기준면에서 돌출된 형상의 상세 표현에 사용된다.

SUBMANIFOLDS WITH PARALLEL NORMAL MEAN CURVATURE VECTOR

  • Jitan, Lu
    • 대한수학회보
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    • 제35권3호
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    • pp.547-557
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    • 1998
  • In this paper, we study submanifolds in the Euclidean space with parallel normal mean curvature vectorand special quadric representation. Especially we give a complete classification result relative to surfaces satisfying these conditions.

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간결하고 효율적인 폴리곤 메쉬의 표현 구조 (A Compact and Efficient Polygonal Mesh Representation)

  • 박상근;이상헌
    • 한국CDE학회논문집
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    • 제9권4호
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    • pp.294-305
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    • 2004
  • Highly detailed geometric models are rapidly becoming commonplace in computer graphics and other applications. These complex models, which is often represented as complex1 triangle meshes, mainly suffer from the vast memory requirement for real-time manipulation of arbitrary geometric shapes without loss of data. Various techniques have been devised to challenge these problems in views of geometric processing, not a representation scheme. This paper proposes the new mesh structure for the compact representation and the efficient handling of the highly complex models. To verify the compactness and the efficiency, the memory requirement of our representation is first investigated and compared with other existing representations. And then we analyze the time complexity of our data structure by the most critical operation, that is, the enumeration of the so-called one-ring neighborhood of a vertex. Finally, we evaluate some elementary modeling functions such as mesh smoothing, simplification, and subdivision, which is to demonstrate the effectiveness and robustness of our mesh structure in the context of the geometric modeling and processing.

B-Spline을 이용한 선체표면의 표현에 관한 연구 (Representation of Ship Hull Surface Using B-Spline)

  • 윤병호;서승완;김원돈;김광욱
    • 대한조선학회지
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    • 제22권3호
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    • pp.19-26
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    • 1985
  • This paper deals with the representation and fairing of ship hull using a B-spline surface which is known as a 3-D model in computer aided free-form design. The first part of this paper is devoted to the fundamental concepts of B-spline theory and its geometrical characteristics. In its second part are described the facillities for efficient application, fast rendering of B-spline surface, and intersection of B-spline surfaces. The examples are presented with actual application to a real ship in the last part. And also a new concept of evaluating the surface fairness by the Gaussian curvature isolines is briefly discussed and its examples are presented.

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유한요소해석과 기하학적 모델링의 연동에 기초한 쉘 곡면의 형상 최적 설계 (Shape Optimization of Shell Surfaces Based on Linkage Framework betweenGeometric Modeling and Finite Element Analysis)

  • 김현철;노희열;조맹효
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2003년도 추계학술대회
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    • pp.1328-1333
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    • 2003
  • In the present study, an integrated framework of geometric modeling, analysis, and design optimization is proposed. Geometric modeling is based on B-spline surface representation. Geometrically-exact shell finite element is implemented in analysis module. Control points of the surface are selected as design variables for optimization, which can make the interaction easier between analysis and surface representation. Sequential linear programming(SLP) is adopted for the shape optimization of surfaces. For the computation of shape sensitivities, semi-analytical method is used. The developed integrated framework should serve as a powerful tool for the geometric modeling, analysis, and shape design of surfaces.

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Implicit Surface Representation of Three-Dimensional Face from Kinect Sensor

  • 수료 아드히 워보워;김은경;김성신
    • 한국지능시스템학회논문지
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    • 제25권4호
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    • pp.412-417
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    • 2015
  • Kinect sensor has two output data which are produced from red green blue (RGB) sensor and depth sensor, it is called color image and depth map, respectively. Although this device's prices are cheapest than the other devices for three-dimensional (3D) reconstruction, we need extra work for reconstruct a smooth 3D data and also have semantic meaning. It happened because the depth map, which has been produced from depth sensor usually have a coarse and empty value. Consequently, it can be make artifact and holes on the surface, when we reconstruct it to 3D directly. In this paper, we present a method for solving this problem by using implicit surface representation. The key idea for represent implicit surface is by using radial basis function (RBF) and to avoid the trivial solution that the implicit function is zero everywhere, we need to defined on-surface point and off-surface point. Based on our simulation results using captured face as an input, we can produce smooth 3D face and fill the holes on the 3D face surface, since RBF is good for interpolation and holes filling. Modified anisotropic diffusion is used to produced smoothed surface.

유추적 사고에 의한 디자인 문제해결의 유형 - 연상된 단어와 스케치 분석을 중심으로 - (A Study on the Types of Design Problem Solving by Analogical Thinking - Focused on the Analysis of Associated Words and Sketch -)

  • 최은희;최윤아
    • 한국실내디자인학회논문집
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    • 제16권2호
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    • pp.63-70
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    • 2007
  • Analogy in problem solving is similarity-based reasoning facilitated by verbal and visual operation. This similarity-based reasoning generally supports initial phase of idea search. Therefore, this study intends to infer the types of problem solving by tracing the analogy use of verbal and visual representation through a experimental research. According to the result of this research, the types of problem solving by analogy are classified into 'evolving', 'divergent', and 'poor conversion' type. Firstly, 'evolving type' is distinguished between 'combination type' associated different contents to develope a new design and 'transformation type' associated similar words and sketches to be continuously revised and developed. In these types usually structural analogy rather than surface analogy is used. Secondly, in 'divergent type' associated words or sketches are individually represented, and among them one design solution is selected. In this type usually surface analogy is used. Thirdly, in 'poor conversion type' interaction between verbal representation and visual representation does not go on smoothly, and the generation of idea is poor. In here surface analogy is mostly used. These findings could form the basis of skill development of idea generation and conversion in design education.

기업의 표현규정이 비대면 감정노동자의 직무만족에 미치는 영향에 관한 연구 (A study of display rule for none face-to-face emotional worker's job satisfaction)

  • 여현진;박지영;문재영
    • 품질경영학회지
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    • 제44권3호
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    • pp.649-660
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    • 2016
  • Purpose: The purpose of this study is to find empirical studies the causal relationship among positive defining representation, negative defining representation, surface acting, deep acting, dissatisfaction of job, and intention of job transfer. Methods: The collected data through the survey by customer satisfaction team of "A" company call center. Results: The result of this study is that emotion and behavior norm influence on deep act of expressing both positive impacts of the employees. Conclusion: Feelings of corporate representation norm is psychologically of employees that because it affects even also must facilitate the surface acts and internal acts of employees and job dissatisfaction at the same time due to emotional dissonance and emotional exhaustion and turnover are hidden on the back emotion norms in the contact department, it should be aware of the need to address the emotional problems. Companies need to develop a variety of programs with attention to addressing the emotional difficulties experienced by workers.