Search results for "computational geometry"

showing 10 items of 139 documents

Modelling Complex Volume Shape Using Ellipsoid: Application to Pore Space Representation

2017

Natural shapes have complex volume forms that are usually difficult to model using simple analytical equations. The complexity of the representation is due to the heterogeneity of the physical environment and the variety of phenomena involved. In this study we consider the representation of the porous media. Thanks to the technological advances in Computed Topography scanners, the acquisition of images of complex shapes becomes possible. However, and unfortunately, the image data is not directly usable for simulation purposes. In this paper, we investigate the modeling of such shapes using a piece wise approximation of image data by ellipsoids. We propose to use a split-merge strategy and a…

010504 meteorology & atmospheric sciencesScale (ratio)Computer scienceComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISIONTangentApproximation algorithmContext (language use)02 engineering and technologyComputational geometry01 natural sciencesEllipsoid0202 electrical engineering electronic engineering information engineeringPiecewise020201 artificial intelligence & image processingRepresentation (mathematics)AlgorithmComputingMethodologies_COMPUTERGRAPHICS0105 earth and related environmental sciences2017 13th International Conference on Signal-Image Technology & Internet-Based Systems (SITIS)
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"Table 49" of "Multiplicity dependence of K*(892)$^{0}$ and $\phi$(1020) production in pp collisions at $\sqrt{s}$ = 13 TeV"

2020

$\phi$/K$_{\mathrm{S}}^{0}$ yield ratio vs transverse momentum - V0M multiplicity class II

13000.0Proton-Proton CollisionsP P --> Phi+X and P P --> K0S+XComputer Science::Computational GeometrySIGyieldPhiResonanceV0M Multiplicity
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"Table 52" of "Multiplicity dependence of K*(892)$^{0}$ and $\phi$(1020) production in pp collisions at $\sqrt{s}$ = 13 TeV"

2020

$\phi$/K$_{\mathrm{S}}^{0}$ double yield ratio vs transverse momentum - V0M multiplicity class II / V0M multiplicity class X

13000.0Proton-Proton CollisionsP P --> phi+X and P P --> K0S+XComputer Science::Computational GeometrySIGyieldPhiResonanceV0M Multiplicity
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"Table 54" of "Multiplicity dependence of K*(892)$^{0}$ and $\phi$(1020) production in pp collisions at $\sqrt{s}$ = 13 TeV"

2020

Significance of $\phi$/K$_{\mathrm{S}}^{0}$ double yield ratio vs transverse momentum - V0M multiplicity class II / V0M multiplicity class X

13000.0Proton-Proton CollisionsP P --> phi+X and P P --> K0S+XComputer Science::Computational GeometrySIGyieldPhiResonanceV0M Multiplicity
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"Table 20" of "Multiplicity dependence of K*(892)$^{0}$ and $\phi$(1020) production in pp collisions at $\sqrt{s}$ = 13 TeV"

2020

$\phi$ transverse momentum spectrum - V0M multiplicity class II

13000.0YieldsProton-Proton CollisionsComputer Science::Computational GeometryNuclear ExperimentSIGPhiResonanceP P --> Phi+XV0M Multiplicity
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"Table 30" of "Multiplicity dependence of K*(892)$^{0}$ and $\phi$(1020) production in pp collisions at $\sqrt{s}$ = 13 TeV"

2020

$\phi$ transverse momentum spectrum ratio to INEL>0 - V0M multiplicity class II

13000.0YieldsProton-Proton CollisionsComputer Science::Computational GeometrySIGPhiResonanceP P --> Phi+XV0M Multiplicity
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Semantic-based Technique for the Automation the 3D Reconstruction Process

2010

Pages: 191 to 198, ISBN: 978-1-61208-104-5; International audience; The reconstruction of 3D objects based on point clouds data presents a major task in many application field since it consumes time and require human interactions to yield a promising result. Robust and quick methods for complete object extraction or identification are still an ongoing research topic and suffer from the complex structure of the data, which cannot be sufficiently modeled by purely numerical strategies. Our work aims at defining a new way of automatically and intelligently processing of 3D point clouds from a 3D laser scanner. This processing is based on the combination of 3D processing technologies and Semant…

3D processing[ INFO.INFO-IA ] Computer Science [cs]/Computer Aided Engineering[INFO.INFO-CG] Computer Science [cs]/Computational Geometry [cs.CG][ INFO.INFO-CG ] Computer Science [cs]/Computational Geometry [cs.CG]knowledge modelingontology[INFO.INFO-IA]Computer Science [cs]/Computer Aided Engineering3D scene reconstruction[INFO.INFO-CG]Computer Science [cs]/Computational Geometry [cs.CG]object identificationmixed strategy[INFO.INFO-IA] Computer Science [cs]/Computer Aided EngineeringSemantic web
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Ein Axiomensystem f�r partielle affine R�ume

1994

A partial linear space with parallelism is called partial affine space if it is embeddable in an affine space with the same pointset preserving the parallelism. These partial affine spaces will be characterized by a system of three axioms for partial linear spaces with parallelism.

AlgebraParallelism (rhetoric)Linear spaceAffine spaceGeometry and TopologyAffine transformationComputer Science::Computational GeometryAxiomMathematicsJournal of Geometry
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Comparison and multiresolution analysis of irregular meshes with appearance attributes

2004

We present in this dissertation a method to compare and to analyse irregular meshes with appearance attributes. First, we propose a mesh comparison method using a new attribute deviation metric. Considered meshes contain geometric and appearance attributes (e.g. color, texture,temperature). The proposed deviation assessment allows the computation of local attribute differences between two meshes. We present an application of this method to mesh simplification algorithm quality assessment.Then we propose two multiresolution analysis schemes for irregular meshes with appearance attributes. First, a mesh is decomposed in a discret number of levels of detail. We introduce a surface geometry rel…

Appearance attributesIrregular meshes[INFO.INFO-GR] Computer Science [cs]/Graphics [cs.GR][INFO.INFO-CV]Computer Science [cs]/Computer Vision and Pattern Recognition [cs.CV]analyse multirésolutionattributs d’apparenceMesh comparisondébruitage adaptatif[INFO.INFO-CG]Computer Science [cs]/Computational Geometry [cs.CG][INFO.INFO-GR]Computer Science [cs]/Graphics [cs.GR][INFO.INFO-CV] Computer Science [cs]/Computer Vision and Pattern Recognition [cs.CV][INFO.INFO-CG] Computer Science [cs]/Computational Geometry [cs.CG]visualisation dépendante des détailscomparaison de maillagesMultiresolution analysismaillages irréguliers
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Documenting carved stones from 3D models. Part II - Ambient occlusion to reveal carved parts.

2021

10 pages; International audience; Revealing carved parts in rock art is of primary importance and remains a major challenge for archaeological documentation. Computational geometry applied to 3D imaging provides a unique opportunity to document rock art. This study evaluates five algorithms and derivatives used to compute ambient occlusion and sky visibility on 3D models of Mongolian stelae, also known as deer stones. By contrast with the previous companion work, models are processed directly in 3D, without preliminary projection. Volumetric obscurance gives the best results for the identification of carved figures. The effects of model resolution and parameters specific to ambient occlusio…

Archeology[SHS.ARCHEO]Humanities and Social Sciences/Archaeology and PrehistoryComputer scienceMaterials Science (miscellaneous)ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION02 engineering and technologyConservationDocumentation01 natural sciencesSoftwareComputer graphics (images)Rock artVolumetric obscuranceProjection (set theory)Deer stoneSpectroscopyComputingMethodologies_COMPUTERGRAPHICSbusiness.industry010401 analytical chemistryVisibility (geometry)Mongolia021001 nanoscience & nanotechnologyComputational geometry0104 chemical sciencesIdentification (information)ArchaeologyChemistry (miscellaneous)Late bronze ageAmbient occlusionRock art0210 nano-technologyScale (map)businessGeneral Economics Econometrics and Finance
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