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In this paper, some existence results for generalized vector equilibrium-like problems (for short, GVELPs) are established by virtue of a generalized KKM-Fan theorem in topological vector spaces. In addition, some applications to vector optimization problems are also given. The results presented in this paper are the extension and improvement of the corresponding results of other authors. [ABSTRACT FROM AUTHOR]

In this paper, we use Schauder and Banach fixed point theorems to study the existence, uniqueness and stability of bounded nonhomogeneous iterative functional differential equations of the form x' (t) = λ1x(t) + λ2x[2](t)+...+λnx[n](t)+f(t). [ABSTRACT FROM AUTHOR]

The topic of rough set theory considers a relation to determine the lower and upper approximations of a set X. Originally, this relation was assumed to be an equivalence relation. This research focuses on using tolerance relations instead of equivalences, i.e. we do not assume the transitivity of the relations. More specifically, in this paper we investigate tolerances induced by irredundant coverings. We characterize the interrelation between the lattices of lower and upper approximations of such tolerances R and p. The theory of Formal Concept Analysis makes it possible to examine the inclusions of the resulting concepts. We also use quasiorders (denoted by ≤ and ≥ (p)) and an equivalence relation (denoted by ker p) for summarizing the connection between tolerances and lattices in a theorem. [ABSTRACT FROM AUTHOR]

The aim of this paper is to obtain the spectrum, fine spectrum, approximate point spectrum, defect spectrum and compression spectrum of the operator ... on the sequence space c0 where the non-zero diagonals are the entries of an oscillatory sequence. [ABSTRACT FROM AUTHOR]

In this paper, the order of simultaneous approximation and Voronovskaja-type results with quantitative estimate for complex q-Kantorovich polynomials (q > 0) attached to analytic functions on compact disks are obtained. In particular, it is proved that for functions analytic in {z ∊ C : ∣z∣ < R}, R > q, the rate of approximation by the q- Durrmeyer - Stancu operators (q > 1) is of order q-n versus 1/n for the classical q-Durrmeyer - Stancu operators. [ABSTRACT FROM AUTHOR]

In this paper we will prove a fixed point theorem of Perov type for cyclic contractions on complete generalized metric spaces. Then, as an application, we will study the existence, uniqueness and approximation of the solution for a system of integral equations. [ABSTRACT FROM AUTHOR]

The functional defined as the difference of the right-hand and the left-hand side of Jensen's inequality is called Jensen's functional. The aim of this paper is to study its lower bounds. More precisely, some refinements of its lower bounds are recaptured under more relaxed conditions on the n-tuple x. [ABSTRACT FROM AUTHOR]

In this paper, we introduce the multivariate Bernstein-Schurer-Stancu operators. Then, we state the Volkov-type theorem and investigate the order of convergence by means of modulus of continuity and by Lipschitz class functionals. Moreover, the inverse theorems are studied for the multivariate Stancu variant of Bernstein operators. [ABSTRACT FROM AUTHOR]

Zeros of minimizers of p-Ginzburg-Landau functional are helpful to understand the location of vortices of superconductivity and superfluid. When p D 2 and the degree of the boundary data around the boundary is ±1, there exists only one zero of the p-Ginzburg-Landau minimizers in the bounded domain. When p > 2, this becomes a more complicated problem. This paper is concerned with the location of the zeros of a radial minimizer of a p-Ginzburg-Landau type functional. The authors use the method of moving planes and the idea of the proof of Pohozaev's identity to verify that the origin is the unique zero of the radial minimizer in the domain. [ABSTRACT FROM AUTHOR]

In this paper we present some existence, uniqueness and Hyers-Ulam stability results for the coupled fixed point of a pair of contractive type operators on complete metric spaces. The approach is based on a Perov type fixed point theorem for contractions. Some applications to integral equations and to boundary value problems are also given. [ABSTRACT FROM AUTHOR]

The aim of this paper is to present a class of linear positive operators of discrete type and its statistical approximation properties obtained by using a Bohman-Korovkin type theorem. [ABSTRACT FROM AUTHOR]