We consider two-stage scattered data fitting with truncated hierarchical B-splines (THB-splines) for the adaptive reconstruction of industrial models. The first stage scheme is devoted to computation local least squares variational spline approximations, exploiting a simple fairness functional handle distributions locally varying density points. Hierarchical quasi-interpolation based on THB-spl...

We present a new method for reconstructing the density function underlying a given histogram. First we analyze the univariate case taking the approximating function in a class of quadratic-like splines with variable degrees. For the analogous bivariate problem we introduce a new scheme based on the Boolean sum of univariate B-splines and show that for a proper choice of the degrees, the splines...

We consider a space of Chebyshev splines whose left and right derivatives satisfy linear constraints that are given by arbitrary non-singular connection matrices. We show that for almost all knot sequences such spline spaces have basis functions whose support is equal to the support of the ordinary B-splines with the same knots. Consequently, there are knot insertion and evaluation algorithms a...

We present the construction of additive multilevel preconditioners, also known as BPX for solution linear system arising in isogeometric adaptive schemes with (truncated) hierarchical B-splines. show that locality spline functions, naturally defined on a structure, can be suitably exploited to design and analyze efficient decompositions. By obtaining smaller subspaces respect standard tensor-pr...

In this paper we generate and study new cubature formulas based on spline quasi-interpolants defined as linear combinations of C bivariate quadratic B-splines on a rectangular domain Ω, endowed with a non-uniform criss-cross triangulation, with discrete linear functionals as coefficients. Such B-splines have their supports contained in Ω and there is no data point outside this domain. Numerical...

The advantages of B-splines for signal representation are well known. This paper explores a fact that seems to be less well known, namely, the possibility of using linear combinations of B-splines to obtain representations that are more stable than the usual ones. We give the best possible Riesz bounds for these linear combinations and calculate their duals, in a generalized sampling context. ...

This paper explores numerical solutions of optimal control problems using B–Spline curves. It is aimed to give a general framework on how to use B–Splines to formulate optimal control problems and to solve them numerically using Nonlinear Trajectory Generation software package. Effects of the selection of the B–Spline parameters, such as, number of intervals, smoothness, piecewise polynomial or...