• Title/Summary/Keyword: Euler operator

Search Result 21, Processing Time 0.027 seconds

Half-edge data structure를 이용한 객체지향 Solid modeling

  • 최봉구;박윤선
    • Proceedings of the Korean Operations and Management Science Society Conference
    • /
    • 1996.04a
    • /
    • pp.96-99
    • /
    • 1996
  • 본 연구는 CAD/CAM에서 3차원 물체를 표현하는 기법중 하나인 Solid Modeling을 구성하는 데이터 구조를 객체지향화 함으로써 보다 효율적이고 유연한 설계개발환경을 제공하고자 한다. 이를 위해서 가장 일반적으로 Solid Modeling을 표현하는 데이터 구조인 기존의 Half-Edge Data Structure를 기본모델로 하여 점(Vortex), 선(Edge), 면(Face), 입체(Solid)를 객체 Class로 하고 Euler Operator를 Method로 하는 객체지향 반모서리 데이터 구조(Object Oriented Half-Edge Data Structure)를 개발하였다.

  • PDF

Sheet Modeling and Transformation of Sheet into Solid Based on Non-manifold Topological Representation (바다양체 위상 표현을 바탕으로 한 박판 형상 모델링 및 솔리드로의 변환)

  • Lee, S.H.;Lee, K.W.
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.13 no.7
    • /
    • pp.100-114
    • /
    • 1996
  • In order to create a solid model more efficiently for a plastic or sheet metal product with a thin and constant thickness, various methods have been proposed up to now. One of the most typical approaches is to create a sheet model initially and then transform it into a solid model automatically for a given thickness. The sheet model as well as the transitive model in sheet modeling procedure is a non-manifold model. However, the previous methods adopted the boundary representations for a solid model as their topological framework. Thus, it is difficult to represent the exact adjacency relationship between topological entities and to implement the topological operations for sheet modeling and the transformation procedure of a sheet into a solid. In this paper, we proposed a sheet modeling system based on a non-manifold topological representation which can represent solids, sheets, wireframes, and their mixture. A set of generalized Euler operators for non-manifold topology as well as the sheet modeling capabilities including adding, bending, and punching functions are provided for easy modeling of sheet objects, and they are perfomed interactively with a two dimensional curve editor. Once a sheet model is completed, it can be transformed into a solid automatically. The transformation procedure is composed of the offset functions and the Boolean operations of sheet models, and it is even more comprehensive and easier to be implemented than the precious methods.

  • PDF

Development of Smart CAD/CAM System for Machining Center Based on B-Rep Solid Modeling Techniques (I) (A Study on the B-Rep Solid Modeler using Half Edge Data Structure) (B-Rep 솔리드모델을 이용한 머시닝 센터용 CAC/CAM 시스템 개발(1): 반모서리 자료구조의 B-Rep 솔리드모델러에 관한 연구)

  • 양희구;김석일
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • 1994.10a
    • /
    • pp.689-694
    • /
    • 1994
  • In this paper, to develop a smart CAD/CAM system for systematically performing from the 3-D solid shape design of products to the CNC cutting operation of products by a machining center, a B-Rep solid modeler is realized based on the half edge data structure. Because the B-Rep solid modeler has the various capabilities related to the solid definition functions such as the creation operation of primitives and the translational and rotational sweep operation, the solid manipulation functions such as the split operation and the Boolean set operation, and the solid inversion function for effectively using the data structure, the 3-D solid shape of products can be easily designed and constructed. Also, besides the automatic generation of CNC code, the B-Rep solid modeler can be used as a powerful tool for realizing the automatic generation of finite elements, the interference check between solids, the structural design of machine tools and robots and so on.

  • PDF

Development of Boolean Operations for CAD System Kernel Supporting Non-manifold Models (비다양체 모델을 수용하는 CAD 시스템 커널을 위한 불리안 조직의 개발)

  • 김성환;이건우;김영진
    • Korean Journal of Computational Design and Engineering
    • /
    • v.1 no.1
    • /
    • pp.20-32
    • /
    • 1996
  • The boundary evaluation technique for Boolean operation on non-manifold models which is regarded as the most popular and powerful method to create and modify 3-D CAD models has been developed. This technique adopted the concept of Merge and Selection in which the CSG tree for Boolean operation can be edited quickly and easily. In this method, the merged set which contains complete information about primitive models involved is created by merging primitives one by one, then the alive entities are selected following the given CSG tree. This technique can support the hybrid representation of B-rep(Boundary Representation) and CSG(Constructive Solid Geometry) tree in a unified non-manifold model data structure, and expected to be used as a basic method for many modeling problems such as data representation of form features, and the interference between them, and data representation of conceptual models in design process, etc.

  • PDF

Non-manifold Modeling Data Structure Based on Open Inventor (Open Inventor에 기초한 비다양체 모델링 자료구조)

  • 박상호;이호영;변문현
    • Korean Journal of Computational Design and Engineering
    • /
    • v.3 no.3
    • /
    • pp.154-160
    • /
    • 1998
  • In this study, we implement the prototype modeler with non-manifold data structure using Open Inventor. In these days, Open Inventor is a popular tool for computer graphics applications, even though Open Inventor could not store topological information including a non-manifold data structure which can represent an incomplete three dimensional shape such as a wireframe and a dangling surface during designing. Using Open Inventor, our modeler can handle a non-manifold model whose data structure is based on the radial edge data structure. A model editor is also implemented as an application which can construct a non-manifold model from two dimensional editing.

  • PDF

On Certain Novel Subclasses of Analytic and Univalent Functions

  • Irmak, Huseyin;Joshi, Santosh Bhaurao;Raina, Ravinder Krishen
    • Kyungpook Mathematical Journal
    • /
    • v.46 no.4
    • /
    • pp.543-552
    • /
    • 2006
  • The purpose of the present paper is to introduce two novel subclasses $\mathcal{T}_{\mu}(n,{\lambda},{\alpha})$ and $\mathcal{H}_{\mu}(n,{\lambda},{\alpha};{\kappa})$ of analytic and univalent functions with negative coefficients, involving Ruscheweyh derivative operator. The various results investigated in this paper include coefficient estimates, distortion inequalities, radii of close-to-convexity, starlikenes, and convexity for the functions belonging to the class $\mathcal{T}_{\mu}(n,{\lambda},{\alpha})$. These results are then appropriately applied to derive similar geometrical properties for the other class $\mathcal{H}_{\mu}(n,{\lambda},{\alpha};{\kappa})$ of analytic and univalent functions. Relevant connections of these results with those in several earlier investigations are briefly indicated.

  • PDF

DECOMPOSITION FORMULAS AND INTEGRAL REPRESENTATIONS FOR SOME EXTON HYPERGEOMETRIC FUNCTIONS

  • Choi, Junesang;Hasanov, Anvar;Turaev, Mamasali
    • Journal of the Chungcheong Mathematical Society
    • /
    • v.24 no.4
    • /
    • pp.745-758
    • /
    • 2011
  • Generalizing the Burchnall-Chaundy operator method, the authors are aiming at presenting certain decomposition formulas for the chosen six Exton functions expressed in terms of Appell's functions $F_3$ and $F_4$, Horn's functions $H_3$ and $H_4$, and Gauss's hypergeometric function F. We also give some integral representations for the Exton functions $X_i$ (i = 6, 8, 14) each of whose kernels contains the Horn's function $H_4$.

Semi-automatic 3D Building Reconstruction from Uncalibrated Images (비교정 영상에서의 반자동 3차원 건물 모델링)

  • Jang, Kyung-Ho;Jang, Jae-Seok;Lee, Seok-Jun;Jung, Soon-Ki
    • Journal of Korea Multimedia Society
    • /
    • v.12 no.9
    • /
    • pp.1217-1232
    • /
    • 2009
  • In this paper, we propose a semi-automatic 3D building reconstruction method using uncalibrated images which includes the facade of target building. First, we extract feature points in all images and find corresponding points between each pair of images. Second, we extract lines on each image and estimate the vanishing points. Extracted lines are grouped with respect to their corresponding vanishing points. The adjacency graph is used to organize the image sequence based on the number of corresponding points between image pairs and camera calibration is performed. The initial solid model can be generated by some user interactions using grouped lines and camera pose information. From initial solid model, a detailed building model is reconstructed by a combination of predefined basic Euler operators on half-edge data structure. Automatically computed geometric information is visualized to help user's interaction during the detail modeling process. The proposed system allow the user to get a 3D building model with less user interaction by augmenting various automatically generated geometric information.

  • PDF

ON THE ANALOGS OF BERNOULLI AND EULER NUMBERS, RELATED IDENTITIES AND ZETA AND L-FUNCTIONS

  • Kim, Tae-Kyun;Rim, Seog-Hoon;Simsek, Yilmaz;Kim, Dae-Yeoul
    • Journal of the Korean Mathematical Society
    • /
    • v.45 no.2
    • /
    • pp.435-453
    • /
    • 2008
  • In this paper, by using q-deformed bosonic p-adic integral, we give $\lambda$-Bernoulli numbers and polynomials, we prove Witt's type formula of $\lambda$-Bernoulli polynomials and Gauss multiplicative formula for $\lambda$-Bernoulli polynomials. By using derivative operator to the generating functions of $\lambda$-Bernoulli polynomials and generalized $\lambda$-Bernoulli numbers, we give Hurwitz type $\lambda$-zeta functions and Dirichlet's type $\lambda$-L-functions; which are interpolated $\lambda$-Bernoulli polynomials and generalized $\lambda$-Bernoulli numbers, respectively. We give generating function of $\lambda$-Bernoulli numbers with order r. By using Mellin transforms to their function, we prove relations between multiply zeta function and $\lambda$-Bernoulli polynomials and ordinary Bernoulli numbers of order r and $\lambda$-Bernoulli numbers, respectively. We also study on $\lambda$-Bernoulli numbers and polynomials in the space of locally constant. Moreover, we define $\lambda$-partial zeta function and interpolation function.

Sheet Offsetting Algorithms for Efficient Solid Modeling for Thin-Walled Parts (얇은 두께 솔리드의 효율적인 모델링을 위한 박판 옵셋 알고리즘 개발)

  • 김현수;이상헌
    • Korean Journal of Computational Design and Engineering
    • /
    • v.5 no.3
    • /
    • pp.242-254
    • /
    • 2000
  • This paper describes an efficient solid modeling method for thin-walled plastic or sheet metal parts, based on the non-manifold offsetting operations. Since the previous methods for modeling and converting a sheet into a solid have adopted the boundary representations for solid object as their topological framework, it is difficult to represent the exact adjacency relationship between topological entities of a sheet model and a mixture of wireframe and sheet models that can appear in the meantime of modeling procedure, and it is hard to implement topological operations for sheet modeling and transformation of a sheet into a solid. To solve these problems, we introduce a non-manifold B-rep and propose a sheet conversion method based on a non-manifold offset algorithm. Because the non-manifold offset aigorithm based on mathematical definitions results in an offset solid with tubular and spherical thickness-faces we modify it to generate the ruled or planar thickness-faces that are mostly shown in actual plastic or sheet metal parts. In addition, in order to accelerate the Boolean operations used the offset algorithm, we also develope an efficient face-face intersection algorithm using topological adjacency information.

  • PDF