Class Of Set-valued Maps Research Articles

Some useful set-valued maps in set optimization

In this article, we introduce several classes of set-valued maps which can be useful in set optimization due to their applications. Exactly, we present some set-valued maps defined by scalar and vector functions and study their properties such as continuity and convexity among others. In addition, we compute their asymptotic maps which can be employed to establish coercivity and existence results in the framework of set optimization problems. Finally, we expose some possible directions for further research.

A fixed point theorem for a new class of set-valued mappings in R-complete (not necessarily complete) metric spaces

In this paper, firstly, we introduce the notion of R-complete metric spaces. This notion let us to consider fixed point theorem in R-complete instead of complete metric spaces. Secondly, as motivated by the recent work of Amini-Harandi (Fixed Point Theory Appl. 2012, 2012:215), we explain a new generalized contractive condition for set-valued mappings and prove a fixed point theorem in R-complete metric spaces which extends some well-known results in the literature. Finally, some examples are given to support our main theorem and also we find the existence of solution for a first-order ordinary differential equation.

Minimax theorems for set-valued maps without continuity assumptions

We introduce several classes of set-valued maps with new generalized convexity properties. We also obtain minimax theorems for set-valued maps which satisfy these convexity assumptions and which are not continuous. Our method consists of the use of a fixed point theorem for weakly naturally quasiconcave set-valued maps, defined on a simplex in a topological vector space, or of a constant selection of quasiconvex set-valued maps.

Coderivatives of gap function for Minty vector variational inequality

The purpose of this paper is to investigate coderivatives of the gap function involving the Minty vector variational inequality. First, we discuss the regular coderivative, the normal coderivative, and the mixed coderivative of a class of set-valued maps. Then, by using the relationships between the coderivatives of a set-valued map and its efficient points set-valued map, we obtain the coderivatives of the gap function for the Minty vector variational inequality.

Derivatives of Set-Valued Maps and Gap Functions for Vector Equilibrium Problems

This paper deals with the set-valued gap functions for vector equilibrium problems and investigates their differential properties using Hadamard directional differentials. Also, contingent and adjacent derivatives of a class of set-valued maps are characterized. Moreover, some basic properties of Φ-contingent and Φ-adjacent cones are given in the presence of a nonsmooth kernel function.

Minimax problems for set-valued mappings with set optimization

In this paper, we introduce a class ofset-valued mappings with some set order relations, which is calleduniformly same-order. For this sort of mappings, we obtain someexistence results of saddle points and depict the structures of thesets of saddle points. Moreover, we obtain a minimax theorem andestablish an equivalent relationship between the minimax theorem anda saddle point theorem for the scalarset-valued mappings, in which the minimization and the maximizationof set-valued mappings are taken in the sense of set optimization.

MINIMAX PROBLEMS OF UNIFORMLY SAME-ORDER SET-VALUED MAPPINGS

In this paper, a class of set-valued mappings is introduced, which is called uniformly same-order. For this sort of mappings, some minimax problems, in which the minimization and the maximization of set-valued mappings are taken in the sense of vector optimization, are investigated without any hypotheses of convexity.

Sensitivity analysis of gap functions for vector variational inequality via coderivatives

The aim of this article is to investigate codifferential properties of a class of set-valued maps and gap function involving vector variational inequality. Relationships between their coderivatives are discussed. Formulae for computing coderivatives of the gap function are established. Optimality conditions of solutions for vector variational inequalities are obtained. The finite-dimensional cases are also discussed.

Differential properties and optimality conditions for generalized weak vector variational inequalities

In this paper, we study a generalized weak vector variational inequality, which is a generalization of a weak vector variational inequality and a Minty weak vector variational inequality. By virtue of a contingent derivative and a Φ-contingent cone, we investigate differential properties of a class of set-valued maps and obtain an explicit expression of its contingent derivative. We also establish some necessary optimality conditions for solutions of the generalized weak vector variational inequality, which generalize the corresponding results in the literature. Furthermore, we establish some unified necessary and sufficient optimality conditions for local optimal solutions of the generalized weak vector variational inequality. Simultaneously, we also show that there is no gap between the necessary and sufficient conditions under an appropriate condition.

General hyperbolicity conditions for set-valued mappings

A definition of hyperbolicity for dynamical systems generated by set-valued mappings of general form in terms of local selectors is given. It is shown that a system hyperbolic in this sense has the shadowing and inverse shadowing properties. It is also shown that the hyperbolicity property holds true for a certain class of set-valued mappings where images of points are convex polytopes. Bibliography: 13 titles.

Second-order asymptotic differential properties and optimality conditions for weak vector variational inequalities

In this paper, by virtue of an asymptotic second-order contingent derivative and an asymptotic second-order Φ-contingent cone, differential properties of a class of set-valued maps are investigated and an explicit expression of their asymptotic second-order contingent derivatives is established. Then, second-order necessary optimality conditions of solutions are obtained for weak vector variational inequalities.

On a perturbation approach to open mapping theorems

The open covering property, also known in the literature as metric regularity, is investigated for certain classes of set-valued maps in a Banach space setting. The focus of the present study is on a perturbation approach for deriving open covering criteria, which stems from a theorem due to Milyutin, and which is developed here by means of an abstract notion of first-order approximation for single-valued maps between normed spaces. As a result, a criterion is achieved for parametric set-valued maps in terms of open covering of their strict approximation. Two applications are presented: the first one relates to Robinson-type theorems in the context of quasidifferential analysis, whereas the second concerns the estimation of the distance from the solution set to a nonsmooth problem in parametric convex optimization.

Second-Order Differential and Sensitivity Properties of Weak Vector Variational Inequalities

In this paper, by using the second-order contingent derivative, second-order differential properties of a class of set-valued maps are investigated and an explicit expression of the second-order contingent derivatives is obtained. Then, by means of a gap function, second-order sensitivity properties are discussed for a weak vector variational inequality.

Differential and sensitivity properties of gap functions for Minty vector variational inequalities

The purpose of this paper is to investigate differential properties of a class of set-valued maps and gap functions involving Minty vector variational inequalities. Relationships between their contingent derivatives are discussed. An explicit expression of the contingent derivative for the class of set-valued maps is established. Optimality conditions of solutions for Minty vector variational inequalities are obtained.

Differentiation of sets in measure

Suppose F ( ε ) , for each ε ∈ [ 0 , 1 ] , is a bounded Borel subset of R d and F ( ε ) → F ( 0 ) as ε → 0 . Let A ( ε ) = F ( ε ) ▵ F ( 0 ) be symmetric difference and P be an absolutely continuous measure on R d . We introduce the notion of derivative of F ( ε ) with respect to ε, d F ( ε ) / d ε = d A ( ε ) / d ε , such that d d ε P ( A ( ε ) ) | ε = 0 = Q ( d d ε A ( ε ) | ε = 0 ) , where Q is another, explicitly described, measure, although not in R d . We discuss why this sort of derivative is needed to study local point processes in neighbourhood of a set: in short, if sequence of point processes N n , n = 1 , 2 , … , is given on the class of set-valued mappings F = { F ( ⋅ ) } such that all F ( ε ) converge to the same F = F ( 0 ) , then the weak limit of the local processes { N n ( A ( ε ) ) , F ( ε ) ∈ F } “lives” on the class of derivative sets { d F ( ε ) / d ε | ε = 0 , F ( ⋅ ) ∈ F } . We compare this notion of the derivative set-valued mapping with other existing notions.

Fixed Points for Directional Multi-Valued k(·)-Contractions

A fixed point theorem for directional multi-valued k(·)-contractions acting m a complete metric space is established which extends similar results both for k(·)-contractions and directional contractions. Such theorem enables to obtain fixed points theorems for the former class of set-valued maps from those valid for the latter one without metrical convexity or proximinality assumptions, thereby contributing to unify the current setting of the theory. Connections with several recent advances on this subject are also examinated.

Optimality criteria in set-valued optimization

AbstractThe main aim of this paper is to obtain optimality conditions for a constrained set-valued optimization problem. The concept of Clarke epiderivative is introduced and is used to derive necessary optimality conditions. In order to establish sufficient optimality criteria we introduce a new class of set-valued maps which extends the class of convex set-valued maps and is different from the class of invex set-valued maps.

Differential and sensitivity properties of gap functions for vector variational inequalities

The purpose of this paper is to investigate differential properties of a class of set-valued maps and gap functions involving vector variational inequalities. Relationship between their contingent derivatives are discussed. A formula computing contingent derivative of the gap functions is established. Optimality conditions of solutions for vector variational inequalities are obtained.

A Note on Quasiconvex Set-Valued Maps

In this paper we first introduce a class of set-valued quasiconvex maps with respect to cones, called cone quasiconvex maps, and obtain a characterization for cone quasiconvexity at a point in terms of star shapedness. We then introduce a general class of set-valued maps, called weak cone quasiconvex maps and discuss the relations of both these classes of maps with directional derivatives studied by Yang [16]. A sufficient optimality criterion is also established for a set-valued minimization problem assuming the map involved to be cone quasiconvex (weak cone quasiconvex).

On D-KKM theorem and its applications

In this paper, we introduce a new class of set-valued mappings in a non-convex setting called D-KKM mappings and prove a general D-KKM theorem. This extends and improves the KKM theorem for several families of set-valued mappings, such as (X, Y), C(X, Y), C (X, Y), C (X, Y) and C (X, Y). In the sequel, we apply our theorem to get some existence results for maximal elements, generalised variational inequalities, and price equilibria.