The Moving Least Squares method (MLS) provides an approximation û of a function u based solely on values u(xj) of u on scattered ”meshless” nodes xj . Derivatives of u are usually approximated by derivatives of û. In contrast to this, we directly estimate derivatives of u from the data, without any detour via derivatives of û. This is a generalized Moving Least Squares technique, and we prove t...

We estimate the rate of the pointwise approximation by operators of Bleimann, Butzer and Hahn of locally bounded functions, and of functions having a locally bounded derivative.

Keywords: Baskakov-Szász operators Modulus of continuity Asymptotic formula Simultaneous approximation Statistical convergence Bounded variation a b s t r a c t In the present paper, we introduce generalized Baskakov-Szász type operators and study some approximation properties of these operators e.g., rate of convergence in ordinary and simultaneous approximation, statistical convergence and th...

In a previous paper [ Fatehi , S. ; et al. J. Chem. Phys. 2013 , 139 , 124112 ], we demonstrated a practical method by which analytic derivative couplings of Boys-localized CIS states can be obtained. In this paper, we now apply that same method to the analysis of triplet-triplet energy transfer systems studied by Closs and collaborators [ Closs , G. L. ; et al. J. Am. Chem. Soc. 1988 , 110 , 2...

The present article deals with the general family of summationintegral type operators. Here, we propose the Durrmeyer variant of the generalized Lupaş operators considered by Abel and Ivan (General Math. 15 (1) (2007) 21-34) and study local approximation, Voronovskaja type formula, global approximation, Lipchitz type space and weighted approximation results. Also, we discuss the rate of converg...

The paper studies a model of fluid flow in fractured porous medium which fractures are distributed uniformly over the volume. This includes nonlinear equation containing several terms with fractional derivatives sense Caputo order belonging to interval 1,2. relevance studying this problem is determined by its practical significance oil industry, since most world’s reserves these types reservoir...

In this paper, we propose an efficient numerical method for solving initial boundary value problem a coupled system of equations consisting nonlinear parabolic partial integro-differential equation and elliptic with term. This has important applied significance in petroleum engineering finds application modeling two-phase nonequilibrium fluid flows porous medium generalized law. The constructio...

We consider the Cauchy problem for a first-order evolution equation with memory in finite-dimensional Hilbert space when integral term is related to time derivative of solution. The main problems approximate solution such nonlocal are due necessity work all previous moments. propose transformation integrodifferential system local evolutionary equations. use approach known theory Volterra equati...

We study approximation of univariate functions deened over the reals. We assume that the rth derivative of a function is bounded in a weighted L p norm with a weight. Approximation algorithms use the values of a function and its derivatives up to order r ? 1. The worst case error of an algorithm is deened in a weighted L q norm with a weight. We study the worst case (information) complexity of ...