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Automatic identification and truncation of boundary outlets in complex imaging-derived biomedical geometries

Xiangmin Jiao, Daniel R. Einstein, Vladimir Dyedov, James P. Carson
2009 Medical and Biological Engineering and Computing  
We present efficient and robust algorithms for automatically identifying and truncating the outlets for complex geometries.  ...  Our approach is based on a conceptual decomposition of objects into tips, segments, and branches, where the tips determine the outlets.  ...  First, we obtain an initial orientation based on a principle component analysis of the intersection of the sphere with the surface.  ... 
doi:10.1007/s11517-009-0501-9 pmid:19526263 pmcid:PMC2734875 fatcat:aahwbk3k2jathiwsiprk2xeuny

Innovative Course of Descriptive Geometry

Irina Sergeyeva, Yelena Korotkova, Edward Kolos, Christian Martinez, S. Bratan, S. Roshchupkin
2021 MATEC Web of Conferences  
Algorithms for the construction of 3D models of intersecting tangent surfaces and surfaces with a common inscribed sphere were developed to control individual tasks.  ...  The relevance, efficiency and advantages of an innovative course using AutoCAD and new teaching material for independent work of both Russian and foreign students were evaluated.  ...  of complexity for low-performing students and the third level of complexity for advanced students, including presentations of the IHW on the Intersection of Surfaces topic with the text in Russian and  ... 
doi:10.1051/matecconf/202134603083 fatcat:4rn7uqoq2fgodpdnppljyrvk7u

Image-Space Caustics and Curvatures

Xuan Yu, Feng Li, Jingyi Yu
2007 15th Pacific Conference on Computer Graphics and Applications (PG'07)  
We derive a ray characteristic equation to compute the two slits, and hence, the caustic surfaces. Using the characteristic equation, we develop a GPU-based algorithm to render the caustics.  ...  Physically caustics can be interpreted from one of two perspectives: in terms of photons gathered on scene geometry, or in terms of a pair of caustic surfaces.  ...  We present a third approach based on the geometry of caustic surfaces. In the literature, these surfaces represent an envelop of light rays [6] .  ... 
doi:10.1109/pg.2007.35 dblp:conf/pg/YuLY07 fatcat:ng5eyden3zefbd5yqsixdcpqpu

The Research on Improved Design and Drawing of Product Forms Based on Reverse Engineering Technology

Chunxia Geng
2013 Research Journal of Applied Sciences Engineering and Technology  
In the analysis of the reverse engineering system model based on the reverse engineering system based on local surface reconstruction model based on existing measurement data directly to display 3D images  ...  In the study, the improved design of the form of product related to the free-form surface treatment, but the use of the product form the point cloud data to obtain a satisfactory surface reconstruction  ...  , based on the polyhedron surface.  ... 
doi:10.19026/rjaset.6.4066 fatcat:74fcr3mmdfhxhktvfjno3owh3y

Numerical Simulation of Dynamically Deforming Aircraft Configurations Using Overset Grids

Yuval Levy
2001 Journal of Aircraft  
An efficient method to locate the intersection point is based on a bilinear inter- polation within a cell of the fuselage mesh.  ...  The points are smoothed using an elliptic grid generator based on the Thompson, Thames, and Mastin algorithm.'?  ... 
doi:10.2514/2.2768 fatcat:hzkusf5wire3dehrwnqbl6t2yq

A robust algorithm for implicit description of immersed geometries within a background mesh

Daniel Baumgärtner, Johannes Wolf, Riccardo Rossi, Pooyan Dadvand, Roland Wüchner
2018 Advanced Modeling and Simulation in Engineering Sciences  
Within the background mesh, the immersed geometry is described implicitly using a discontinuous distance function based on a level-set approach.  ...  The contained geometry is assumed to be given as triangulated surface.  ...  To detect actual intersections, an octree-based search algorithm was proposed.  ... 
doi:10.1186/s40323-018-0113-8 fatcat:43tmnlpcyjg3plzwa5uune53aa

Surface mesh regeneration considering curvatures

A. C. O. Miranda, L. F. Martha, P. A. Wawrzynek, A. R. Ingraffea
2008 Engineering with Computers  
This work describes an automatic algorithm for unstructured mesh regeneration on arbitrarily shaped threedimensional surfaces.  ...  In this implementation, the only information about the surface geometry is a set of triangles.  ...  Introduction This paper describes an algorithm for generating triangle finite-element meshes on surfaces of arbitrary shape and curvatures.  ... 
doi:10.1007/s00366-008-0119-9 fatcat:42i27lcl4jhm3guvz6nml2mw2u

Local Orthogonal Cutting Method for Computing Medial Curves and Its Biomedical Applications

Xiangmin Jiao, Daniel R. Einstein, Vladimir Dyedov
2010 SIAM Journal on Scientific Computing  
We assume the input geometry is given by a surface triangulation, such as that obtained by an isosurfacing algorithm (see [26] for a survey of such algorithms).  ...  These concepts lend themselves to robust numerical techniques and result in an algorithm that is efficient and noise resistant.  ...  For clarity, we divide the approaches into two categories: algorithms that are based on the volume, and those based on the surface.  ... 
doi:10.1137/090767170 pmid:20628546 pmcid:PMC2901897 fatcat:jafuehlrv5cdvab547wvflbz2m

A Development Perspective of Point-Based Computer Graphics

Ajahati Mukti
2021 Science Insights  
Based on the digital geometry processing of point-sampled model, various algorithms were reviewed, and some related key techniques were compared with the potential perspective of the future work in this  ...  Every object has its characteristic shape, appearance and responses to physical interactions. Computer graphics center on those three components of an object to bring them onto the computer display.  ...  Drawing Algorithm Based on Efficiency The efficiency-based rendering algorithm uses an opaque square to represent each point. Although efficient, it will produce graphics aliasing.  ... 
doi:10.15354/si.21.re231 fatcat:t4eq72xj4fhtlafmjmzrkutywy

Focal Surfaces of Discrete Geometry [article]

Jingyi Yu, Xiaotian Yin, Xianfeng Gu, Leonard McMillan, Steven Gortler
2007 Symposium on geometry processing : [proceedings]. Symposium on Geometry Processing  
We develop both CPU and GPU-based algorithms to efficiently approximate these two slits and, hence, the focal meshes.  ...  The differential geometry of smooth three-dimensional surfaces can be interpreted from one of two perspectives: in terms of oriented frames located on the surface, or in terms of a pair of associated focal  ...  We then develop both CPU and GPU-based algorithms to efficiently approximate the ray congruency and, hence, the focal surfaces.  ... 
doi:10.2312/sgp/sgp07/023-032 fatcat:b6m3oujlqnhgxlgvnsvkh7zuem

HeatTracer - A novel Monte Carlo radiative heat transfer tool for cavity receivers simulation

João P. Cardoso, Luís Filipe Mendes, João Farinha Mendes
2019 SOLARPACES 2018: International Conference on Concentrating Solar Power and Chemical Energy Systems  
The main characteristics of this tool are presented, including the main physical models as well as some of the more relevant mathematical and computational algorithms.  ...  This work introduces the development of a new tool, HeatTracer, for the simulation of radiative heat transfer based on the Monte Carlo method, directed to the study of radiation exchange for arbitrary  ...  Description of the Receiver Geometry The 3D cavity geometry is defined by a set of triangle-based tessellated surfaces, being each surface defined by the user through an STL (stereolithography) file.  ... 
doi:10.1063/1.5117673 fatcat:mrjvk7v4gvdw5f6xjxzldus3ya

Manifold Dual Contouring

Scott Schaefer, Tao Ju, Joe Warren
2007 IEEE Transactions on Visualization and Computer Graphics  
Our main contribution is an octree-based topology-preserving vertex-clustering algorithm for adaptive contouring.  ...  We present an extension of DC that further guarantees that the mesh generated is a manifold even under adaptive simplification.  ...  Delfinado and Edelsbrunner [27] first introduced an incremental algorithm that can be used to compute the Euler characteristic of a growing triangular surface that expands by adding one triangle at a  ... 
doi:10.1109/tvcg.2007.1012 pmid:17356225 fatcat:25dmqd5atfhwtgbwytbuegmeqq

Robust interactive cutting based on an adaptive octree simulation mesh

Martin Seiler, Denis Steinemann, Jonas Spillmann, Matthias Harders
2011 The Visual Computer  
Since the intersection is performed on a coarse base resolution of the simulation mesh, this can be done efficiently.  ...  The resulting algorithm is a variant of the one presented in [23] . In contrast to them, we can draw on the regular structure of the octree, making the algorithm more efficient.  ... 
doi:10.1007/s00371-011-0561-3 fatcat:nf6qzmwajnhl5pvivvxdrdocyy

Research on a fiber ring generating algorithm for manufacturing fiber composite rotating structures of complex geometry

Xianfeng Wang, Huaqiao Wang, Jun Xiao
2018 Transactions of the Canadian Society for Mechanical Engineering  
In this paper, a trajectory generating algorithm was proposed based on the centroid curve of a quasirotational structure, while the centroid curve is the connection of centroids of the cross-sections of  ...  An efficient number of profiles will be identified to avoid any overlap among neighboring profiles along the centroid curve.  ...  based on centroid curve The geometry relationship between a line and a plane (a) The line is outside the plane (b) The line is on the plane (c) The line intersects with the plane Intersection Poid curve  ... 
doi:10.1139/tcsme-2017-0042 fatcat:lsfkuovzj5ceflkcglosf5iwdq

Sound Propagation and Reconstruction Algorithm Based on Geometry

Jihun Park
2019 International Journal of Online and Biomedical Engineering (iJOE)  
The algorithm being developed in this paper is based on a ray sound theory.  ...  We compare two approaches and propose a geometry-based sound computation method for outdoor simulation. This approach is computationally more efficient than the forward sound tracing.  ...  We constructed three-dimensional terrain using fractal geometry, and developed an algorithm for sound propagation simulation for outdoor terrains and indoor rooms.  ... 
doi:10.3991/ijoe.v15i13.11212 fatcat:ea4sg26q7vd4thxdjbjzftjnpu
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