On the problem of retracting balls onto their boundary.
On the radius of a set in a Hilbert space
On the range of nonlinear operators with linear asymptotes which are not invertible
On the Schauder fixed point theorem
The paper contains a survey of various results concerning the Schauder Fixed Point Theorem for metric spaces both in single-valued and multi-valued cases. A number of open problems is formulated.
On the solution set of a two point boundary value problem.
On the Solvability of Semilinear Elliptic Equations with Nonlinear Boundary Conditions.
On the stability analysis of Darboux problem on both bounded and unbounded domains
In this paper, we first investigate the existence and uniqueness of solution for the Darboux problem with modified argument on both bounded and unbounded domains. Then, we derive different types of the Ulam stability for the proposed problem on these domains. Finally, we present some illustrative examples to support our results.
On the Stability of Jungck–Mann, Jungck–Krasnoselskij and Jungck Iteration Processes in Arbitrary Banach Spaces
In this paper, we establish some stability results for the Jungck–Mann, Jungck–Krasnoselskij and Jungck iteration processes in arbitrary Banach spaces. These results are proved for a pair of nonselfmappings using the Jungck–Mann, Jungck–Krasnoselskij and Jungck iterations. Our results are generalizations and extensions to a multitude of stability results in literature including those of Imoru and Olatinwo [8], Jungck [10], Berinde [1] and many others.
On the stability of some fixed point iteration procedures with errors.
On the stability of the fixed point property in spaces.
On the structure of fixed point sets of pseudo-contractive mappings. II.
On the structure of fixed point sets of pseudo-contractive mappings
On the structure of fixed point sets of some compact maps in the Fréchet space
The aim of this note is 1. to show that some results (concerning the structure of the solution set of equations (18) and (21)) obtained by Czarnowski and Pruszko in [6] can be proved in a rather different way making use of a simle generalization of a theorem proved by Vidossich in [8]; and 2. to use a slight modification of the “main theorem” of Aronszajn from [1] applying methods analogous to the above mentioned idea of Vidossich to prove the fact that the solution set of the equation (24), (25)...
On the topological dimension of the solutions sets for some classes of operator and differential inclusions
In the present paper, we give the lower estimation for the topological dimension of the fixed points set of a condensing continuous multimap in a Banach space. The abstract result is applied to the fixed point set of the multioperator of the form where is the superposition multioperator generated by the Carathéodory type multifunction F and S is the shift of a linear injective operator. We present sufficient conditions under which this set has the infinite topological dimension. In the last...
On the Uniqueness of the Topological Degree.
On the weakly(α, ψ, ξ)-contractive condition for multi-valued operators in metric spaces and related fixed point results
The aim of this paper is to introduce the concept of a new nonlinear multi-valued mapping so called weakly (α, ψ, ξ)-contractive mapping and prove fixed point results for such mappings in metric spaces. Our results unify, generalize and complement various results from the literature. We give some examples which support our main results while previous results in literature are not applicable. Also, we analyze the existence of fixed points for mappings satisfying a general contractive inequality of...
On ultrametric space.
On uniqueness of conjugacy of continuous and piecewise monotone functions.
On unrestricted products of (W) contractions
Given a family of (W) contractions on a reflexive Banach space X we discuss unrestricted sequences . We show that they converge weakly to a common fixed point, which depends only on x and not on the order of the operators if and only if the weak operator closed semigroups generated by are right amenable.
On weak and strong convergence theorems for two nonexpansive mappings in Banach spaces