Multivariate polysplines are a new mathematical technique that has arisen from a synthesis
of approximation theory and the theory of partial differential equations. It is an invaluable …

We study the existence and shape preserving properties of a generalized Bernstein operator
B n fixing a strictly positive function f 0 , and a second function f 1 such that f 1 /f 0 is strictly …

Mathematical models are traditionally used to analyze the long-term global evolution of
epidemics, to determine the potential and severity of an outbreak, and to provide critical …

We investigate non-stationary orthogonal wavelets based on a non-stationary interpolatory
subdivision scheme reproducing a given set of exponentials with real-valued parameters. …

We develop a novel TVBG-SEIR spline model for analysis of the coronavirus infection (COVID-19).
It aims to analyze the long-term global evolution of the epidemics" controlled" by the …

Objective This study focused on Bulgarian patient cohorts harbouring a single documented
chronic comorbidity–cardiovascular pathology, an oncological disease or a chronic …

Let L be a linear differential operator with constant coefficients of order n and complex
eigenvalues λ 0 ,…,λ n . Assume that the set U n of all solutions of the equation Lf=0 is closed …

… [9] OI Kounchev, Minimizing the integral of the Laplacian of a function squared with prescribed
values … [13] O. Kounchev, H. Render, The approximation order of polysplines, Proc. Amer. …

We show that the scaling spaces defined by the polysplines of order $ p $ provide approximation
order $2 p. $ For that purpose we refine the results on one-dimensional approximation …

Radial Basis Functions (RBF) have found a wide area of applications. We consider the case
of polyharmonic RBF (called sometimes polyharmonic splines) where the data are on …