Simultaneous approximation by Gauss–Weierstrass–Wachnicki operators
Abstract In this note, we spotlight a generalization of Weierstrass integral operators introduced by Eugeniusz Wachnicki. The construction involves modified…
(original)
On some control problems for Kolmogorov type systems
Abstract The paper deals with some control problems related to the Kolmogorov system for two interacting populations. For the first…
On the localization and numerical computation of positive radial solutions for φ-Laplace equations in the annulus
Abstract The paper deals with the existence and localization of positive radial solutions for stationary partial differential equations involving a…
Applications of fibre contraction principle to some classes of functional integral equations
Abstract Let \(a<c<b)\) real numbers, \((\mathbb{B},|\cdot|)\) a (real or complex) Banach space, \(H\in C([a,b]\times [a,c]\times\mathbb{B},\mathbb{B})\), \(K\in C([a,b]^{2}\times\mathbb{B},\mathbb{B})\), \(g\in C([a,b]),\mathbb{B} ,A:C([a,c],\mathbb{B})\rightarrow…
On the determination of the orbital elements in the light travel time effect
Abstract This paper deals with the light travel time effect in binary systems with variable components. The methods for estimation…
Positive radial solutions for Dirichlet problems via a Harnack-type inequality
Abstract We deal with the existence and localization of positive radial solutions for Dirichlet problems involving \(\phi\)-Laplacian operators in a…
Semilinear problems with poly-Laplace type operators
AbstractThe paper deals with semilinear operator equations involving iterates of a strongly monotone symmetric linear operator. In particular there are…
Componentwise localization of solutions to systems of operator inclusions via Harnack type inequalities
Abstract We establish compression-expansion type fixed point theorems for systems of operator inclusions with decomposable multivalued maps. The approach is…
Iterates of multidimensional approximation operators via Perov theorem
AbstractThe starting point is an approximation process consisting of linear and positive operators. The purpose of this note is to…
On some applications of the controllability principle for fixed point equations
Abstract The aim of this paper is to draw attention to a general principle for solving control problems for operator…