Controllability of second‐order impulsive neutral functional differential inclusions in Banach spaces

In this paper, we shall prove the controllability of second‐order impulsive neutral functional differential inclusions with infinite delay in Banach spaces. The results are obtained by using the theory of strongly continuous cosine families and a fixed point theorem for multi‐valued mappings. As an example, we also consider an second‐order impulsive neutral functional differential equation with infinite delay. Copyright © 2009 John Wiley & Sons, Ltd.     

The RKHSM for solving neutral functional–differential equations with proportional delays

In this paper, the reproducing kernel Hilbert space method (RKHSM) is applied to neutral functional–differential equations with proportional delays. Its approximate solution is obtained by truncating the n‐term of exact solution. Some examples are displayed to demonstrate the computation efficiency of the method. We also compare the performance of the method with a particular Runge–Kutta method, a one‐leg θ‐method and variational iteration method. Experiment dates indicate that the RKHSM is an accurate and efficient method to solve neutral functional–differential equations with proportional delays. Copyright © 2012 John Wiley & Sons, Ltd.     

Population structure increases the evolvability of genetic algorithms

Populations are shaped by the spatial structure of their environment: space organizes interactions between individuals locally, and gives rise to a global population structure. Both local and global population structures can have a profound influence on the evolutionary dynamics of a population. To characterize this influence, we use genetic algorithms with several distinct contact structures to evolve cellular automata, which perform a density classification task. We find that local contact structures (modeled as graphs with various topologies) that limit the number of breeding partners show greater evolvability than well‐mixed populations. Furthermore, we show that the evolvability of well‐mixed populations is enhanced in a metapopulation setting of coupled subpopulations. © 2012 Wiley Periodicals, Inc. Complexity, 2012     

Cascade search principle and its applications to the coincidence problems of n one-valued or multi-valued mappings

The problem of the construction of a multi-cascade with a given limit subset A is considered in a metric space X. A multi-cascade is a discrete multi-valued dynamic system with the translation semigroup (Z?0,+). The cascade search principle using so-called search functionals is suggested. It gives a solution of the problem. Also, an estimation is obtained for the distance between any initial point x and every correspondent limit point. Several applications of one-valued and multi-valued versions of the mentioned cascade search principle are given for the cases when the limit subset A is (1) the full (or expanded) preimage of a closed subspace under a mapping from X to another metric space; (2) the coincidence set (or expanded coincidence set) of n mappings from X to another metric space (n>1); (3) the common preimage (or the expanded one) of a closed subspace under n mappings; and (4) the common fixed point set of n mappings of the space X into itself (n?1). Generalizations of the previous authors results are obtained. And, in particular cases, generalizations of some recent results by A.V. Arutyunov on coincidences of two mappings and a generalization of Banach fixed point principle are obtained.     

A delay decomposition approach for robust dissipativity and passivity analysis of neutral‐type neural networks with leakage time‐varying delay

This article presents the robust dissipativity and passivity analysis of neutral‐type neural networks with leakage time‐varying delay via delay decomposition approach. Using delay decomposition technique, new delay‐dependent criteria ensuring the considered system to be ‐γ dissipative are established in terms of strict linear matrix inequalities. A new Lyapunov–Krasovskii functional is constructed by dividing the discrete and neutral delay intervals into m and l segments, respectively, and choosing different Lyapunov functionals to different segments. Further, the dissipativity behaviors of neural networks which are affected due to the sensitiveness of the time delay in the leakage term have been taken into account. Finally, numerical examples are provided to show the effectiveness of the proposed method. © 2015 Wiley Periodicals, Inc. Complexity 21: 248–264, 2016     

Solution of the Ulam stability problem for Euler–Lagrange–Jensen k‐quintic mappings

In this paper, we are introducing pertinent Euler–Lagrange–Jensen type k‐quintic functional equations and investigate the ‘Ulam stability’ of these new k‐quintic functional mappings f:X→Y, where X is a real normed linear space and Y a real complete normed linear space. We also solve the Ulam stability problem for Euler–Lagrange–Jensen alternative k‐quintic mappings. Copyright © 2016 John Wiley & Sons, Ltd.     

On the rate of convergence in the individual ergodic theorem for the action of a semigroup

We consider the individual ergodic theorem for the action of a semigroup of measurepreserving mappings. We estimate the rate of convergence using estimates for the probability of large deviations for the ergodic averages with an essentially bounded averaging function. We find estimates for the rate of convergence of the ergodic averages in the cases of Benedicks–Carleson quadratic mappings, expanding mappings of Pomeau–Manneville type with a neutral point, and multidimensional shifts.     

Nonexpansive mappings in metric and Banach spaces

The fundamental fixed point theorem for nonexpansive mappings is reformulated in the setting of a metric space possessing a convexity structure, and various constructive and nonconstructive proofs are compared. A new proof of the Browder-Göhde demiclosedness principle for mappings of the formI–T, T nonexpansive, is given, and a related result of R. E. Bruck in discussed.     

关于序列覆盖紧映射

本文利用了ｃｓ网、序列邻域网、序列开网和弱基的概念,讨论了空间中点正则覆盖,一致覆盖和点有限覆盖的点星网之间的关系．建立了度量空间在几类序列覆盖（紧）映射下象空间的特征,特别地证明了度量空间的序列覆盖（或１序列覆盖）紧映象等价于具有点正则ｃｓ网的空问,回答了Ｔａｎａｋａ等提出的一个问题．     

Existence results for impulsive neutral stochastic evolution inclusions in Hilbert space

This paper is concerned with the existence of mild solutions of a class of impulsive neutral stochastic evolution inclusions in Hilbert space in the case where the right hand side is convex or nonconvex-valued. The results are obtained by using two fixed point theorems for multivalued mappings and evolution system theory.     

An Extension of Set-Valued Contraction Principle for Mappings on a Metric Space with a Graph and Application

In this paper, we obtain an existence theorem for fixed points of contractive set-valued mappings on a metric space endowed with a graph. This theorem unifies and extends several fixed point theorems for mappings on metric spaces and for mappings on metric spaces endowed with a graph. As an application, we obtain a theorem on the convergence of successive approximations for some linear operators on an arbitrary Banach space. This result yields the well-known Kelisky–Rivlin theorem on iterates of the Bernstein operators on C[0,1].     

Approximating fixed points of asymptotically nonexpansive mappings in Banach spaces by metric projections

In this paper, a strong convergence theorem for asymptotically nonexpansive mappings in a uniformly convex and smooth Banach space is proved by using metric projections. This theorem extends and improves the recent strong convergence theorem due to Matsushita and Takahashi [S. Matsushita, W. Takahashi, Approximating fixed points of nonexpansive mappings in a Banach space by metric projections, Appl. Math. Comput. 196 (2008) 422–425] which was established for nonexpansive mappings.     

不具有关于锥的例外簇的映射

给出Hilbert空间到其自身不具有关于锥的例外族的映射条件，利用Hilbert空间可表为闭凸锥与负对偶锥的特点研究映射关于锥的例外簇的特性，证明了可通过映射在某紧凸子集上的性态判断其例外簇的存在与否，并讨论单调和沿射线单调映射的不具例外簇问题。     

Common fixed point theorems and minimax inequalities in locally convex Hausdorff topological vector spaces

In this article, we introduce the concept of a family of set-valued mappings generalized Knaster–Kuratowski–Mazurkiewicz (KKM) w.r.t. other family of set-valued mappings. We then prove that if X is a nonempty compact convex subset of a locally convex Hausdorff topological vector space and 𝒯 and 𝒮 are two families of self set-valued mappings of X such that 𝒮 is generalized KKM w.r.t. 𝒯, under some natural conditions, the set-valued mappings S ∈ 𝒮 have a fixed point. Other common fixed point theorems and minimax inequalities of Ky Fan type are obtained as applications.     

关于sn可度量空间的注记

具有σ局部有限sn网的空间称为sn可度量空间.本文利用紧覆盖映射、点星网、CF族的概念,给出了sn可度量空间的新刻画.     

Controllability of Neutral Functional Differential and Integrodifferential Inclusions with Infinite Delay

Sufficient conditions are derived for the controllability of neutral functional differential and integrodifferential inclusions with infinite delay in a Banach space. The results are obtained by using a fixed-point theorem for condensing maps due to Martelli. An example is given to illustrate the results.     

Approximation of common fixed points for a countable family of relatively nonexpansive mappings in a Banach space and applications

In this paper, we prove a strong convergence theorem by the hybrid method for a countable family of relatively nonexpansive mappings in a Banach space. We also establish a new control condition for the sequence of mappings {T_n} which is weaker than the control condition in Lemma 3.1 of Aoyama et al. [K. Aoyama, Y. Kimura, W. Takahashi and M. Toyoda, Approximation of common fixed points of a countable family of nonexpansive mappings in a Banach space, Nonlinear Anal. 67 (2007) 2350-2360]. Moreover, we apply our results for finding a common fixed point of two relatively nonexpansive mappings in a Banach space and an element of the set of solutions of an equilibrium problem in a Banach space, respectively. Our results are applicable to a wide class of mappings.     

Stability of coincidence points and properties of covering mappings

Properties of closed set-valued covering mappings acting from one metric space into another are studied. Under quite general assumptions, it is proved that, if a given α-covering mapping and a mapping satisfying the Lipschitz condition with constant β < α have a coincidence point, then this point is stable under small perturbations (with respect to the Hausdorff metric) of these mappings. This assertion is meaningful for single-valued mappings as well. The structure of the set of coincidence points of an α-covering and a Lipschitzian mapping is studied. Conditions are obtained under which the limit of a sequence of α-covering set-valued mappings is an (α–?)-covering for an arbitrary ? > 0.     

Stability of linear multistep methods for nonlinear neutral delay differential equations in Banach space

This paper is devoted to investigating the nonlinear stability properties of linear multistep methods for the solution to neutral delay differential equations in Banach space. Two approaches to numerically treating the “neutral term” are considered, which allow us to prove several results on numerical stability of linear multistep methods. These results provide some criteria for choosing the step size such that the numerical method is stable. Some examples of application and a numerical experiment, which further confirms the main results, are given.     

Global lagrange stability of complex‐valued neural networks of neutral type with time‐varying delays

In this article, the problem of global exponential stability in Lagrange sense of neutral type complex‐valued neural networks (CVNNs) with delays is investigated. Two different classes of activation functions are considered, one can be separated into real part and imaginary part, and the other cannot be separated. Based on Lyapunov theory and analytic techniques, delay‐dependent criteria are provided to ascertain the aforementioned CVNNs to be globally exponentially stable GES in Lagrange sense. Moreover, the proposed sufficient conditions are presented in the form of linear matrix inequalities which could be easily checked by Matlab. Finally, two simulation examples are given out to demonstrate the validity of theory results. © 2016 Wiley Periodicals, Inc. Complexity 21: 438–450, 2016