Search results for " graph"

showing 10 items of 1277 documents

A comparison of local parametric C0 Bézier interpolants for triangular meshes

2011

Parametric curved shape surface schemes interpolating vertices and normals of a given triangular mesh with arbitrary topology are widely used in computer graphics for gaming and real-time rendering due to their ability to effectively represent any surface of arbitrary genus. In this context, continuous curved shape surface schemes using only the information related to the triangle corresponding to the patch under construction, emerged as attractive solutions responding to the requirements of resource-limited hardware environments. In this paper we provide a unifying comparison of the local parametric C^0 curved shape schemes we are aware of, based on a reformulation of their original constr…

Shape propertiesGeneral EngineeringBézier curveTopologyComputer Graphics and Computer-Aided DesignC0 local parametric interpolantRendering (computer graphics)Human-Computer InteractionComputer graphicsMAT/08 - ANALISI NUMERICABézier triangleTriangle meshPolygon meshComputingMethodologies_COMPUTERGRAPHICSParametric statisticsMathematics
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Implementing Immersive Clustering with VR Juggler

2005

Continuous, rapid improvements in commodity hardware have allowed users of immersive visualization to employ high-quality graphics hardware, high-speed processors, and significant amounts of memory for much lower costs than would be possible with high-end, shared memory computers traditionally used for such purposes. Mimicking the features of a single shared memory computer requires that the commodity computers act in concert—namely, as a tightly synchronized cluster. In this paper, we describe the clustering infrastructure of VR Juggler that enables the use of distributed and clustered computers for the display of immersive virtual environments. We discuss each of the potential ways to syn…

Shared memoryComputer scienceHuman–computer interactionGraphics hardwareOperating systemScene graphGraphicsVirtual realityCluster analysiscomputer.software_genrecomputerVisualization
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Peeling of multilayer graphene creates complex interlayer sliding patterns

2015

Peeling, shearing, and sliding are important mechanical phenomena in van der Waals solids. However, theoretically they have been studied mostly using minimal periodic cells and in the context of accurate quantum simulations. Here, we investigate the peeling of large-scale multilayer graphene stacks with varying thicknesses, stackings, and peeling directions by using classical molecular dynamics simulations with a registry-dependent interlayer potential. Simulations show that, while at large scale the peeling proceeds smoothly, at small scale the registry shifts and sliding patterns of the layers are unexpectedly intricate and depend both on the initial stacking and on the peeling direction.…

Shearing (physics)Materials scienceCondensed Matter - Mesoscale and Nanoscale Physicsta114Condensed matter physicsGrapheneMechanical PhenomenaStackingFOS: Physical sciencesNanotechnologysimulationCondensed Matter Physicsmultilayer grapheneElectronic Optical and Magnetic Materialslaw.inventionMolecular dynamicssymbols.namesakelawMesoscale and Nanoscale Physics (cond-mat.mes-hall)symbolssimulointipeelingvan der Waals forceQuantumPhysical Review B
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Electron transfer mechanism in Shewanella loihica PV-4 biofilms formed at graphite electrode

2012

Abstract Electron transfer mechanisms in Shewanella loihica PV-4 viable biofilms formed at graphite electrodes were investigated in potentiostat-controlled electrochemical cells poised at oxidative potentials (0.2 V vs. Ag/AgCl). Chronoamperometry (CA) showed a repeatable biofilm growth of S. loihica PV-4 on graphite electrode. CA, cyclic voltammetry (CV) and its first derivative shows that both direct electron transfer (DET) mediated electron transfer (MET) mechanism contributes to the overall anodic (oxidation) current. The maximum anodic current density recorded on graphite was 90 μA cm − 2 . Fluorescence emission spectra shows increased concentration of quinone derivatives and riboflavi…

ShewanellaElectroactive biofilmBioelectric Energy SourcesExtracellular Electron TransferRiboflavinInorganic chemistryBiophysicsElectrochemical cellElectron TransportElectron transferGraphite electrodeElectrochemistryGraphitePhysical and Theoretical ChemistryElectrodesMicroscopy ConfocalChemistryQuinonesBiofilmmediated electron transferElectrochemical TechniquesGeneral MedicineChronoamperometryAnodeSpectrometry FluorescenceShewanella loihica PV- 4Extracellular Electron Transfer; Shewanella loihica PV- 4; Electroactive biofilms; Graphite electrode; mediated electron transferBiofilmsMicroscopy Electron ScanningGraphiteDifferential pulse voltammetryCyclic voltammetryOxidation-ReductionBioelectrochemistry
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Seed‐Layer‐Free Atomic Layer Deposition of Highly Uniform Al 2 O 3 Thin Films onto Monolayer Epitaxial Graphene on Silicon Carbide

2019

Atomic layer deposition (ALD) is the method of choice to obtain uniform insulating films on graphene for device applications. Owing to the lack of out-of-plane bonds in the sp(2) lattice of graphene, nucleation of ALD layers is typically promoted by functionalization treatments or predeposition of a seed layer, which, in turn, can adversely affect graphene electrical properties. Hence, ALD of dielectrics on graphene without prefunctionalization and seed layers would be highly desirable. In this work, uniform Al2O3 films are obtained by seed-layer-free thermal ALD at 250 degrees C on highly homogeneous monolayer (1L) epitaxial graphene (EG) (amp;gt;98% 1L coverage) grown on on-axis 4H-SiC(00…

SiCMaterials sciencePhysics::Opticslaw.inventionchemistry.chemical_compoundAtomic layer depositionlawLattice (order)MonolayerPhysics::Atomic and Molecular ClustersSilicon carbidePhysics::Chemical PhysicsThin filmCondensed Matter::Quantum Gasesatomic force microscopybusiness.industryAtomic force microscopyGrapheneMechanical EngineeringCondensed Matter Physicsepitaxial graphenechemistryMechanics of Materialsatomic layer depositionOptoelectronicsatomic force microscopy; atomic layer deposition; epitaxial graphene; SiCEpitaxial graphenebusinessDen kondenserade materiens fysikAdvanced Materials Interfaces
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Random Feature Approximation for Online Nonlinear Graph Topology Identification

2021

Online topology estimation of graph-connected time series is challenging, especially since the causal dependencies in many real-world networks are nonlinear. In this paper, we propose a kernel-based algorithm for graph topology estimation. The algorithm uses a Fourier-based Random feature approximation to tackle the curse of dimensionality associated with the kernel representations. Exploiting the fact that the real-world networks often exhibit sparse topologies, we propose a group lasso based optimization framework, which is solve using an iterative composite objective mirror descent method, yielding an online algorithm with fixed computational complexity per iteration. The experiments con…

Signal Processing (eess.SP)FOS: Computer and information sciencesComputer Science - Machine LearningComputational complexity theoryComputer scienceApproximation algorithmTopology (electrical circuits)Network topologyMachine Learning (cs.LG)Kernel (statistics)FOS: Electrical engineering electronic engineering information engineeringTopological graph theoryElectrical Engineering and Systems Science - Signal ProcessingOnline algorithmAlgorithmCurse of dimensionality
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SART3D: A MATLAB toolbox for spatial audio and signal processing education

2019

Signal processingGeneral Computer ScienceComputer scienceComputer graphics (images)General EngineeringMatlab toolboxEducationComputer Applications in Engineering Education
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From optimization to algorithmic differentiation: a graph detour

2021

This manuscript highlights the work of the author since he was nominated as "Chargé de Recherche" (research scientist) at Centre national de la recherche scientifique (CNRS) in 2015. In particular, the author shows a thematic and chronological evolution of his research interests:- The first part, following his post-doctoral work, is concerned with the development of new algorithms for non-smooth optimization.- The second part is the heart of his research in 2020. It is focused on the analysis of machine learning methods for graph (signal) processing.- Finally, the third and last part, oriented towards the future, is concerned with (automatic or not) differentiation of algorithms for learnin…

Signaux sur graphesOptimisation convexe[STAT.ML]Statistics [stat]/Machine Learning [stat.ML]High dimensional dataGraph signalsStatistiques en grande dimensionAutomatic differentiation[MATH.MATH-OC] Mathematics [math]/Optimization and Control [math.OC][MATH.MATH-OC]Mathematics [math]/Optimization and Control [math.OC][STAT.ML] Statistics [stat]/Machine Learning [stat.ML]Convex optimizationDifférentiation automatique
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Homeomorphic graph manifolds: A contribution to the μ constant problem

1999

Abstract We give a characterization, in terms of homological data in covering spaces, of those maps between (3-dimensional) graph manifolds which are homotopic to homeomorphisms. As an application we give a condition on a cobordism between graph manifolds that guarantees that they are homeomorphic. This in turn is applied to give a partial result on the μ -constant problem in (complex) dimension three.

SingularityDimension (graph theory)CobordismBanach manifoldHomology equivalenceCovering spaceμ constant problemMathematics::Algebraic TopologyMathematics::Geometric TopologyDistance-regular graphManifoldCombinatoricsCoxeter graphSeifert fibered spaceMilnor fiberGraph manifoldEdge-transitive graphRicci-flat manifoldComplex algebraic surfaceGeometry and TopologyMathematics::Symplectic Geometry3-manifoldHomeomorphismMathematicsTopology and its Applications
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Sinòpico. Subtle Signs of Historical Reconaissance / Sinòpico. Sottili segni di ricognizione storica

2011

Potere raccontare attraverso una mostra, fortemente voluta dai suoi curatori e unica nel suo genere monografico, il lavoro eccellente di un illustratore come Primo Sinòpico, e farlo nella città di Cagliari dove lui è nato, è per noi un motivo di grande orgoglio. Primo Sinòpico, anzi soltanto Sinòpico, come firmava i suoi lavori, in un processo di sostituzione del nome di battesimo prima e di riduzione dello pseudonimo poi, è un crogiolo di culture diverse, addensatesi e diventate un tutt’uno nella terra sarda che lo vede partire giovane per quel continente che presto riconoscerà merito, innovazione ed eccellenza al suo lavoro. We are extremely proud to present within this exhibition, one th…

Sinòpico illustrazione storia del design grafico graphic designSettore ICAR/13 - Disegno IndustrialeSinòpico illustration history og graphic design graphic design
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