International Conference on Smart Media and Applications最新文献

{"title":"Accurate computation of the medial axis of a polyhedron","authors":"T. Culver, J. Keyser, Dinesh Manocha","doi":"10.1145/304012.304030","DOIUrl":"https://doi.org/10.1145/304012.304030","url":null,"abstract":"We present an accurate and efficient algorithm to compute the internal Voronoi region and medial axis of a 3-D polyhedron. It uses exact arithmetic and representations for accurate computation of the medial axis. The sheets, seams, and junctions of the medial axis are represented as trimmed quadric surfaces, algebraic space curves, and points with algebraic coordinates, respectively. The algorithm works by recursively finding neighboring junctions along the seam curves. It uses spatial decomposition and linear programming to speed up the search step. We also present a new algorithm for analysis of the topology of an algebraic plane curve, which is the core of our medial axis algorithm. To speed up the computation, we have designed specialized algorithms for fast computation on implicit geometric structures. These include lazy evaluation based on multivariate Stiirm sequences, fast resultant computation, curve topology analysis, and floating-point filters. The algorithm has been implemented and we highlight its performance on a number of examples.","PeriodicalId":286112,"journal":{"name":"International Conference on Smart Media and Applications","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131147469","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mutationable generative feature-based design with floating datum system","authors":"Yonghong Huang, W. Tang, Rongxi Tang","doi":"10.1145/304012.304052","DOIUrl":"https://doi.org/10.1145/304012.304052","url":null,"abstract":"This paper presents a generative feature-based design methodology that supports cutting & pasting of features and modifying feature-based model in a localized way. A floating datum system is built up to guide feature’s definition. The modification of product model is not only carried out by reexecuting the feature history tree in a sequential way , it also supports the manipulation of product design in a flexible way, such as cutting and pasting of features, extracting a portion of a successful product design and merging it into the new product. Object entities to which the datum is attached can be deleted, but the datum and the related features are still existing, and temporarily l’loating in the workspace. Reusing a portion of old products requires high level editability of feature-based design. To design a new style product through ;tt” ;y;J[PJly the value of old dimensions and attributes will but also arise replacing objects, updating constrains and semantics, cutting and pasting features and so on. The new product may inherent attributes from serials of old parts. It can be called a distant relative, and not a family member. We call such kind of design a.s mutationable design. In order to ease the process of modifying feature-based models: 0 A floating datum system is introduced to guide the design and edit process. 0 Virtual clatum is used to break down the relationship between the selected group and the product model. Through matching and replacing virtual datum with the same type objects, the broken relationships between cut features and product model are recovered. Cut features can be pasted at new place in the same model or in different model.","PeriodicalId":286112,"journal":{"name":"International Conference on Smart Media and Applications","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115922644","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Three dimensional freeform sculpting via zero sets of scalar trivariate functions","authors":"A. Raviv, G. Elber","doi":"10.1145/304012.304037","DOIUrl":"https://doi.org/10.1145/304012.304037","url":null,"abstract":"This paper presents a three dimensional interactive sculpting paradigm that employs a collection of scalar uniform trivariate Bspline functions. The sculpted object is evaluated as the zero set of the sum of the collection of the trivariate functions defined over a three dimensional working space, resulting in multi-resolution control capabilities. The continuity of the sculpted object is governed by the continuity of the trivariates. The manipulation of the objects is conducted by modifying the scalar control coefficients of the meshes of the participating trivariates. Real time visualization is achieved by incrementally computing a polygonal appra’ximation via the Marching Cubes algorithm. The exploitation of trivariates in this context benefits from the different properties of the Bspline’s representation such as subdivision, refinement and convex hull containment. A system developed using the presented approach has b’een used in various modeling applications including reverse engineering.","PeriodicalId":286112,"journal":{"name":"International Conference on Smart Media and Applications","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115944674","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A computerized design environment for functional modeling of mechanical products","authors":"Y.-M. Deng, S. Tor, G. Britton","doi":"10.1145/304012.304013","DOIUrl":"https://doi.org/10.1145/304012.304013","url":null,"abstract":"This paper presents the strategies and the methods for the development of a computerized functional modeling design environment to support the conceptual phase of mechanical product design. A new design concept called behavioral scenario is introduced. The modeling process begins with an initial function decomposition and a conversion of the required function into immediate function. This information is then used to develop a causal behavioral process that consists of a network of sub-behaviors. Each sub-behavior is identified by matching its function (intended output action) and the required driving input (intended input action) with the behavioral scenario of a relevant physical phenomenon. The corresponding physical components for each sub-behavior can then be constructed, with respect to the derived behavioral process, to form a preliminary functional design model. Based on the above strategies, a functional modeling design environment has been developed. It consists of an initial function decomposition and conversion module, a causal behavioral process generation module, and a library of domainrelevant physical phenomena. The modules and associated functional modeling tools are described. A design case study is presented to illustrate the applicability of the modeling strategies and the usefulness of the design environment.","PeriodicalId":286112,"journal":{"name":"International Conference on Smart Media and Applications","volume":"73 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124843591","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A novel FEM-based dynamic framework for subdivision surfaces","authors":"Chhandomay Mandal, Hong Qin, B. Vemuri","doi":"10.1145/304012.304031","DOIUrl":"https://doi.org/10.1145/304012.304031","url":null,"abstract":"Subdivision surfaces have been extensively used to model smooth shapes of arbitrary topology. Recursive subdivision on an userdefined initial control mesh generates a visually pleasing smooth surface in the limit. However, users have to carefully specify the initial mesh and/or painstakingly manipulate the control vertices at different levels of subdivision hierarchy to satisfy various functional and aesthetic requirements in the limit surface. This modeling drawback results from the lack of direct manipulation tools for the limit surface. In this paper, we integrate physicsbased modeling techniques with geometric subdivision methodology and present an unified approach for arbitrary subdivision schemes. Our dynamic framework permits users to directly manipulate the limit subdivision surface via physics-based ”force” tools. The key contribution of this unified approach is to formulate the smooth limit surface of any subdivision scheme as a single type of novel finite elements. The geometric and dynamic features of our subdivision-based finite elements depend on the subdivision scheme involved. We present our finite element method (FEM) and formulation for the modified butterfly and Catmull-Clark subdivision schemes, and further generalize our dynamic framework for any subdivision scheme. Our FEM-based approach significantly advances the state-of-the-art of physics-based geometric modeling because (1) our dynamic framework provides a universal physicsbased solution to any subdivision scheme beyond frequently-used and popular spline-like subdivision techniques; (2) we systematically devise a natural mechanism that allows users to intuitively deform any subdivision surface; (3) we represent the smooth limit surface of any subdivision scheme using a single type of novel subdivision-based finite elements. Our experiments demonstrate that the new unified FEM-based framework promises a greater potential of subdivision techniques for solid modeling, finite element analysis, and engineering design.","PeriodicalId":286112,"journal":{"name":"International Conference on Smart Media and Applications","volume":"439 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122887569","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Level set diagrams of polyhedral objects","authors":"F. Lazarus, Anne Verroust-Blondet","doi":"10.1145/304012.304025","DOIUrl":"https://doi.org/10.1145/304012.304025","url":null,"abstract":"Shape descriptors and feature-based representations are of primary interests in the area of solid modeling. They allow us for easier storage, recognition and general treatments of objects. Axial structures such as skeletons are popular shape descriptors which have been widely studied. Most of the studies focus on a particular type of skeleton called the Medial Axis. Medial Axes can be extracted from discrete volumetric data as well as boundary-based representations. In the later case, however, no algorithm is known to perform well and accurately. We propose a new paradigm for constructing one dimensional axial structures associated with a polyhedral object. These structures, called the level set diagrams, are associated with scalar functions defined over the set of vertices of a polyhedron. We study in details the level set diagram associated with the shortest path distance to a source point. This particular association fits nicely into a theoretical framework and presents interesting properties for the purpose of shape description.","PeriodicalId":286112,"journal":{"name":"International Conference on Smart Media and Applications","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122889141","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Improved constructions of Delaunay based contour surfaces","authors":"Siu-Wing Cheng, T. Dey","doi":"10.1145/304012.304061","DOIUrl":"https://doi.org/10.1145/304012.304061","url":null,"abstract":"We revisit a method due to Boissonnat for surface reconstruc tion from parallel slices based on Delaunay triangulations. We e liminate the costly step of computing the three dimensional Dela unay triangulation, and instead compute the surface triangles d ir ctly. A non self-intersecting tiling is automatically guaranteed by these triangulations. Our experiment on some medical data shows that the method is effective. CR Categories: I.4.5 [Image Processing and Computer Vision]: Scene Analysis—Surface fitting;","PeriodicalId":286112,"journal":{"name":"International Conference on Smart Media and Applications","volume":"15 12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127657839","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Extended variational design technology—foundation for integrated design automation","authors":"J. C. Chung, T. Hwang, Chien-Tai Wu, Yu Jiang, Jia-Yi Wang, Yong Bai, H. Zou","doi":"10.1145/304012.304014","DOIUrl":"https://doi.org/10.1145/304012.304014","url":null,"abstract":"Engineering design is an iterative process with a fundamental need for the consistent management and propagation of product dependencies. Constraint-based design provides a unified framework to meet this critical need, but there are known issues due to the complexity of the problem within three-dimensional space. This paper presents results from a decade of research into graph theory and numerical solution techniques to address issues such as user comprehension and multiplicity of solutions. The proposed solution, Extended Variational Design Technology (VGX), utilizes an innovative Drag and Drop user interaction paradigm to improve comprehension performance, and usability. It is also demonstrated that VGX technology can provide common mathematical foundation to support flexible and integrated product design, assembly and analysis.","PeriodicalId":286112,"journal":{"name":"International Conference on Smart Media and Applications","volume":"202 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124528327","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fast volume-preserving free form deformation using multi-level optimization","authors":"G. Hirota, R. Maheshwari, M. Lin","doi":"10.1145/304012.304036","DOIUrl":"https://doi.org/10.1145/304012.304036","url":null,"abstract":"We present an efficient algorithm for preserving the total volume of a solids wdergoing free-form deformation using discrete level-of-detail representations. Given the boundary representation of a solid and user-specified deformation, the algorithm computes the new node positions of the de,formation lattice, while minimizing the elastic energy subject to the volumepreserving criterion. During each iteration, a non-linear optimizer computes the volume deviation and its derivatives based on a triangular approximation, which requires a finely tessellated mesh to achieve the desired accuracy. To reduce the computational cost, we exploit the multi-level representations of the boundary sugaces to greatly accelerate the performance of the non-linear optimizer. This technique also provides interactive response by progressively refining the solution. Furthermore, it is generally applicable to lattice-based free-form deformation and its variants. Our implementation has been applied to several compkx solids. We have been able to achieve an order of magnitude performance improvement over the conventional methods.","PeriodicalId":286112,"journal":{"name":"International Conference on Smart Media and Applications","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129904210","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Integrated mechanically based CAE system","authors":"P. Kagan, A. Fischer, P. Bar-Yoseph","doi":"10.1145/304012.304015","DOIUrl":"https://doi.org/10.1145/304012.304015","url":null,"abstract":"In the product development cycle interaction between design and analysis is very intensive. However, currently existing Computer Aided Engineering (CAE) systems substantially limit such interaction since design and analysis are realized in them as two isolated modules. These limitations can be distinguished on two levels: the conceptual level and the technical level. On the conceptual level a gap exists according to the functionality of each module: the design module is based on purely geometric operations, while the analysis module is based on physical phenomena. On the technical level an environmental gap exists that is characterized by differences in mathematical representation and computational methods. This is partially dictated by the functionality of each module. As a result of these limitations, each iteration between design and analysis and vice versa requires remodeling of the object and conversion of its mathematical representation. This severely restricts development process flexibility and substantially reduces overall precision and efficiency. In order to overcome these problems, a mechanical B-Spline Finite Element model is proposed in this work to be used for both geometric design and mechanical analysis. With this approach the target object is modeled as a physical entity from the very beginning of the geometric design stage. Furthermore, both modules utilize the same computational environment B-Spline Finite Element, and the same representational environment B-Spline functions. Therefore, design and analysis are integrated into a completely unified system, and corresponding analysis operations can be performed simultaneously the geometric design. Technically, this eliminates remodeling and conversion operations between the design and analysis stages of the product development cycle. Conceptually, this allows engineers to substantially shorten the product development cycle time, test many more design variants, tune the final product more finely according to its functionality and to reduce the total product development cost. Examples that verify the feasibility and demonstrate the performance of the proposed Integrated Mechanically Based CAE system are presented for sculptured surface-like objects.","PeriodicalId":286112,"journal":{"name":"International Conference on Smart Media and Applications","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115349771","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}