The Perron-Frobenius Theorem says that if A is a nonnegative square matrix some power of which is positive, ihen there exî sts an .v,, such thai A ".\/\\A "x\\ converges to x,j for all .v > 0, There are many classical proofs of this theorem, all depending on a connection between positivily of a matrix and properties of ils eigenvalues. A more modern proof, due to Garrett Birkhoff. is based on t...

The purpose of this paper is to present the definition of [Formula: see text]-contractive mapping and to discuss the relation of [Formula: see text]-contractive mappings and [Formula: see text]-contractive mappings. Furthermore, the generalized [Formula: see text]-contraction mapping principle has been proved without the uniqueness condition. Meanwhile, the generalized [Formula: see text]-contr...

and Applied Analysis 3 Definition 1.10 see 5 . Let X,G be a G-metric space and f, g : X → X be given mappings. We say that f is a generalized weakly G-contraction mapping of type B with respect to g if for all x, y, z ∈ X, the following inequality holds: ψ ( G ( fx, fy, fz )) ≤ ψ ( G ( gx, gx, fy ) G ( gy, gy, fz ) G ( gz, gz, fx ) 3 ) − φGgx, gx, fy, Ggy, gy, fz, Ggz, gz, fx, 1.2

By a dynamical system (X, T ) we mean the action of the semigroup (Z,+) on a metrizable topological space X induced by a continuous selfmap T : X → X. Let M(X) denote the set of all compatible metrics on the space X. Our main objective is to show that a selfmap T of a compact space X is a Banach contraction relative to some d1 ∈ M(X) if and only if there exists some d2 ∈ M(X) which, regarded as...

A semi{discrete spatial nite diierence approximation and two fully discrete nite diierence approximations to the complex Ginzburg{Landau equation are considered in this paper. The existence of an inertial manifold is proved inside a discrete H 1 absorbing ball for the semi{discrete approximation by showing certain spectral properties hold for the linear operator and certain Lipschitz properties...

Essential extensions and p-extensions have been studied for commutative rings with identity in various articles, such as [2], [3], and [13]. The present article applies these concepts to certain subrings of C(X). Moreover, the article introduces a new ring extension, called a pg-extension, and determines its relation to both essential extension and p-extension. It turns out that the pg-extensio...