Search results for " B-spline"

showing 6 items of 6 documents

A Property on Singularities of NURBS Curves

2002

We prove that if a.n open Non Uniform Rational B-Spline curve of order k has a singular point, then it belongs to both curves of order k - 1 defined in the k - 2 step of the de Boor algorithm. Moreover, both curves are tangent at the singular point.

Pure mathematicsSingularityFamily of curvesCurve fittingTangentGeometryGravitational singularitySingular point of a curveNon-uniform rational B-splineDe Boor's algorithmMathematics::Numerical AnalysisMathematics
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Functional linear regression with functional rensponse application to prediction of electricity consumption

2008

Functional linear regression model linking observations of a functional response variable with measurements of an explanatory functional variable is considered. The slope function is estimated with a tensor product splines. Some computational issues are addressed by means of a simulation study. This model serves to analyze a real data set concerning electricity consumption in Sardinia. The interest lies in predicting either incoming weekend or incoming weekdays consumption curves if actual weekdays consumption is known.

Functional linear regression functional response ARH(1) penalized least squares B-splines electricity consumption in Sardegna.
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Absolutely summing operators on C[0,1] as a tree space and the bounded approximation property

AbstractLet X be a Banach space. For describing the space P(C[0,1],X) of absolutely summing operators from C[0,1] to X in terms of the space X itself, we construct a tree space ℓ1tree(X) on X. It consists of special trees in X which we call two-trunk trees. We prove that P(C[0,1],X) is isometrically isomorphic to ℓ1tree(X). As an application, we characterize the bounded approximation property (BAP) and the weak BAP in terms of X∗-valued sequence spaces.

Banach spacesAbsolutely summing operatorsTwo-trunk treesContinuous functions on [01]Linear B-splinesBounded approximation propertiesJournal of Functional Analysis
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A reexamination of voltage distortion for classical carrier-based vs B-Spline modulation of three-phase Voltage Sources Inverters

2015

Voltage waveform improvement has been the object of several investigations for many years and a manifold of different solutions have been proposed to reduce the harmonic content in Voltage Source Inverters (VSI) power application. In many cases this improvements have been obtained by modifying the reference voltage modulating signal. The recent introduction of cardinal B-spline functions, used as carrier signals, has given rise to a new modulation technique whose main characteristic is a lower value of the Total Harmonic Distortion (THD). After the discussion on the B-Spline modulation principle and on its computational effort, a performance comparisons is carried out by means of Total Harm…

THDvoltage waveform improvementTotal Harmonic Distortionharmonic contentroot mean squareSettore ING-IND/32 - Convertitori Macchine E Azionamenti Elettricivoltage distortionHarmonic analysisControl theoryDistortionclassical carrierinvertorInverterVoltage sourceMathematicsreference voltage modulating signalTotal harmonic distortionmean square error methodRMSTHD analyzerConvolutionSpace vector pulse width modulationharmonic distortioncardinal B-spline functionSplines (mathematics)three-phase voltage sources inverterHarmonicsPulse-Width-Modulated InverterHarmonicB-spline modulationHarmonic analysiVoltage reference
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Adaptive smoothing spline using non-convex penalties

2022

We propose a new adaptive penalty for smoothing via penalized splines. The new form of adaptive penalization is based on penalizing the differences of the coefficients of adjacent bases, using non-convex penalties. This makes possible to estimate curves with varying amounts of smoothness. Comparisons with respect to some competitors are presented.

regression B-spline P-spline adaptive smoothing non-convex penalties SCAD MCP
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Exploring parallel capabilities of an innovative numerical method for recovering image velocity vectors field

2010

In this paper an efficient method devoted to estimate the velocity vectors field is investigated. The method is based on a quasi-interpolant operator and involves a large amount of computation. The operations characterizing the computational scheme are ideal for parallel processing because they are local, regular and repetitive. Therefore, the spatial parallelism of the process is studied to rapidly proceed in the computation on distributed multiprocessor systems. The process has shown to be synchronous, with good task balancing and requiring a small amount of data transfer.

ComputationNumerical analysisProcess (computing)MultiprocessingField (computer science)Computational scienceComputer Science ApplicationsSettore MAT/08 - Analisi NumericaOperator (computer programming)Parallel processing (DSP implementation)Modeling and SimulationModelling and SimulationImage velocity vectors field Quasi-interpolant operator B-spline functions Distributed multiprocessor systemsAlgorithmMathematicsData transmissionMathematical and Computer Modelling
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