Results 31 to 40 of about 507 (130)

On generalization of Petryshyn's fixed point theorem and its application to the product of n-nonlinear integral equations

AIMS Mathematics, 2023
Regarding the Hausdorff measure of noncompactness, we provide and demonstrate a generalization of Petryshyn's fixed point theorem in Banach algebras. Comparing this theorem to Schauder and Darbo's fixed point theorems, we can skip demonstrating closed ...
Ateq Alsaadi, Manochehr Kazemi , Mohamed M. A. Metwali   +2 more
doaj   +1 more source

Compactness of quadruple band matrix operator and geometric properties

Annales Universitatis Paedagogicae Cracoviensis: Studia Mathematica, 2022
In this work, we characterize the class of compact matrix operators from c0(Q), c(Q) and l∞(Q) into c0, c and l∞, respectively, with the notion of the Hausdorff measure of noncompactness.
Mustafa Cemil Bişgin, Abdulcabbar Sönmez   +1 more
doaj  

On the Extended Version of Krasnoselśkiĭ’s Theorem for Kannan-Type Equicontractive Mappings

Mathematics, 2023
The purpose of the paper is to establish a sufficient condition for the existence of a solution to the equation T(u,C(u))=u using Kannan-type equicontractive mappings, T:A×C(A)¯→Y, where C is a compact mapping, A is a bounded, closed and convex subset of
Huaping Huang, Subhadip Pal, Ashis Bera, Lakshmi Kanta Dey   +3 more
doaj   +1 more source

Hilfer-type fractional differential switched inclusions with noninstantaneous impulsive and nonlocal conditions

Nonlinear Analysis, 2018
In this paper, we study a new class of nonlocal problems for noninstantaneous impulsive Hilfer-type fractional differential switched inclusions in Banach spaces.
JinRong Wang, Ahmed Gamal Ibrahim, Donal O’Regan   +2 more
doaj   +1 more source

Compact Operators for Almost Conservative and Strongly Conservative Matrices

Abstract and Applied Analysis, 2014
We obtain the necessary and sufficient conditions for an almost conservative matrix to define a compact operator. We also establish some necessary and sufficient (or only sufficient) conditions for operators to be compact for matrix classes (f,X), where ...
S. A. Mohiuddine, M. Mursaleen, A. Alotaibi   +2 more
doaj   +1 more source

Factorizations and minimality of the Calkin Algebra norm for C(K)$C(K)$‐spaces

Journal of the London Mathematical Society, Volume 112, Issue 4, October 2025.
Abstract For a scattered, locally compact Hausdorff space K$K$, we prove that the essential norm on the Calkin algebra B(C0(K))/K(C0(K))$\mathcal {B}(C_0(K))/\mathcal {K}(C_0(K))$ is a minimal algebra norm. The proof relies on establishing a quantitative factorization for the identity operator on c0$c_0$ through noncompact operators T:C0(K)→X$T: C_0(K)
Antonio Acuaviva
wiley   +1 more source

Generalized φ‐Pullback Attractors in Time‐Dependent Spaces: Application to a Nonautonomous Wave Equation With Time‐Dependent Propagation Velocity

Mathematical Methods in the Applied Sciences, Volume 48, Issue 14, Page 13456-13474, 30 September 2025.
ABSTRACT We present sufficient conditions to obtain a generalized (φ,D)$$ \left(\varphi, \mathfrak{D}\right) $$‐pullback attractor for evolution processes on time‐dependent phase spaces, where φ$$ \varphi $$ is a given decay function and D$$ \mathfrak{D} $$ is a given universe.
Matheus Cheque Bortolan, Carlos Pecorari Neto, Heraclio López Lázaro, Paulo N. Seminario Huertas   +3 more
wiley   +1 more source

Uniqueness on average of large isoperimetric sets in noncompact manifolds with nonnegative Ricci curvature

Communications on Pure and Applied Mathematics, Volume 78, Issue 9, Page 1656-1702, September 2025.
Abstract Let (Mn,g)$(M^n,g)$ be a complete Riemannian manifold which is not isometric to Rn$\mathbb {R}^n$, has nonnegative Ricci curvature, Euclidean volume growth, and quadratic Riemann curvature decay. We prove that there exists a set G⊂(0,∞)$\mathcal {G}\subset (0,\infty)$ with density 1 at infinity such that for every V∈G$V\in \mathcal {G}$ there ...
Gioacchino Antonelli, Marco Pozzetta, Daniele Semola   +2 more
wiley   +1 more source

Rearrangement and Convergence in Spaces of Measurable Functions

Journal of Inequalities and Applications, 2007
We prove that the convergence of a sequence of functions in the space L0 of measurable functions, with respect to the topology of convergence in measure, implies the convergence μ-almost everywhere (μ denotes the Lebesgue measure) of the sequence ...
A. Trombetta, G. Trombetta, D. Caponetti   +2 more
doaj   +2 more sources

Statistical disaggregation—A Monte Carlo approach for imputation under constraints

Scandinavian Journal of Statistics, Volume 52, Issue 3, Page 1376-1421, September 2025.
Abstract Equality‐constrained models naturally arise in problems in which the measurements are taken at different levels of resolution. The challenge in this setting is that the models usually induce a joint distribution which is intractable. Resorting to instead sampling from the joint distribution by means of a Monte Carlo approach is also ...
Shenggang Hu, Hongsheng Dai, Fanlin Meng, Louis Aslett, Murray Pollock, Gareth O. Roberts   +5 more
wiley   +1 more source