Currently displaying 1 – 5 of 5

Showing per page

Order by Relevance | Title | Year of publication

Fixed points, eigenvalues and surjectivity for (ws)-compact operators on unbounded convex sets

Afif Amar — 2013

Open Mathematics

The paper studies the existence of fixed points for some nonlinear (ws)-compact, weakly condensing and strictly quasibounded operators defined on an unbounded closed convex subset of a Banach space. Applications of the newly developed fixed point theorems are also discussed for proving the existence of positive eigenvalues and surjectivity of quasibounded operators in similar situations. The main condition in our results is formulated in terms of axiomatic measures of weak noncompactness.

Nonlinear Leray-Schauder alternatives and application to nonlinear problem arising in the theory of growing cell population

Afif Amar — 2011

Open Mathematics

Motivated by a mathematical model of an age structured proliferating cell population, we state some new variants of Leray-Schauder type fixed point theorems for (ws)-compact operators. Further, we apply our results to establish some new existence and locality principles for nonlinear boundary value problem arising in the theory of growing cell population in L 1-setting. Besides, a topological structure of the set of solutions is provided.

Some fixed point theorems and existence of weak solutions of Volterra integral equation under Henstock-Kurzweil-Pettis integrability

Afif Ben Amar — 2011

Commentationes Mathematicae Universitatis Carolinae

In this paper we examine the set of weakly continuous solutions for a Volterra integral equation in Henstock-Kurzweil-Pettis integrability settings. Our result extends those obtained in several kinds of integrability settings. Besides, we prove some new fixed point theorems for function spaces relative to the weak topology which are basic in our considerations and comprise the theory of differential and integral equations in Banach spaces.

Measures of noncompactness in locally convex spaces and fixed point theory for the sum of two operators on unbounded convex sets

Józef BanaśAfif Ben Amar — 2013

Commentationes Mathematicae Universitatis Carolinae

In this paper we prove a collection of new fixed point theorems for operators of the form T + S on an unbounded closed convex subset of a Hausdorff topological vector space ( E , Γ ) . We also introduce the concept of demi- τ -compact operator and τ -semi-closed operator at the origin. Moreover, a series of new fixed point theorems of Krasnosel’skii type is proved for the sum T + S of two operators, where T is τ -sequentially continuous and τ -compact while S is τ -sequentially continuous (and Φ τ -condensing, Φ τ -nonexpansive...

Page 1

Download Results (CSV)