实线性锥距离空间中带有锥W-距离的不动点定理

在实线性锥距离空间中给出锥、W-距离的概念及一些性质．由此在实线性锥距离空间中建立了压缩型和扩张型两类不动点定理,其中压缩条件和扩张条件中均含有锥W-距离．     

实线性锥距离空间和不动点定理

给出了实线性锥距离空间的概念,其中锥距离取值到没有拓扑结构的实线性空间,并在实线性锥距离空间中建立了几个新的不动点定理.利用非线性标量化函数证明了这些不动点定理与距离空间中相应形式的不动点定理等价.我们的结果改进了锥距离空间中的一些现有不动点定理.     

巴拿赫代数上锥b-距离空间中压缩映射不动点定理

给出了巴拿赫代数上锥b-距离空间的概念,利用迭代法探究了巴拿赫代数上锥b-距离空间中压缩映射不动点定理,证明了广义利普希茨映射在没有正规性的条件下,仍存在不动点并且是唯一的.     

半序赋范空间及增算子的不动点定理

在赋范线性空间E中定义了由E上连续性泛函确定的半序,并由半序引出E上的锥,讨论了半序和锥的若干性质,最后证明了几个单调增算子的不动点定理。     

弱正则锥和正则锥的等价性

M.A.Kransnosel'skii在《Positive solutions of operator equations》一书中引入了正则锥和弱正则锥的概念,显然正则锥一定是弱正则锥。本文证明了弱正则锥并不比正则锥广泛,即:在一切Banach空间中弱正则锥是正则的,从而为非赋范线性拓扑空间中引入正则性提供了思路。     

线性锥系统的Tucker型相容性定理

为了将线性规划中的基础理论之一的Tucker定理推广到一般线性锥系统上,应用对偶锥的概念和线性锥系统的Farkas引理,给出了一般线性系统的Tucker定理,所得结果显示含齐次线性不等式组的线性锥系统和它的对偶系统都存在Tucker定理,且Tucker定理结论的表达式基本相同,这为进一步研究锥规划提供了便利.     

实无限维线性空间中的较多序

本文引入实无限维线性空间中的较多锥和严格较多锥，利用它们定义较多序，讨论较多序的性质，由此得出，实无限维线性空间中的任何两个元素都可以按较多序进行比较．     

序扰动多目标规划的锥次微分稳定性

对于局部凸拓扑向量空间的多目标规划问题,本文研究并得到当确定空间序的控制锥受扰动,它们的锥有效点（解）集和锥弱有效点（解）集分别在锥次微分和锥弱次微分意义下的稳定性结果.     

有界线性空间中含有Q-距离的Ekeland变分原理

有界线性空间中引入了Q-距离的概念,建立了一类向量值Ekeland变分原理,其目标函数是从有界线性空间映到锥序的实线性空间,并且扰动项中含有Q-距离．由此可以得到有界线性空间中现有的一些Ekeland变分原理．同时建立了有界线性空间中的向量值Caristi不动点定理,也给出二者的等价性．     

序凸锥为非点式锥时向量极值问题的Lagrange乘子定理

本文在非常一般的偏序线性空间中,利用Morris序列以及商空间理论,讨论了序凸锥为非点式锥,且所含映射的均为集到集映射的向量极值问题的Lagrange乘子定理。     

Characterization of subdual latticial cones in Hilbert spaces by the isotonicity of the metric projection

The subdual latticial cones in Hilbert spaces are characterized by the isotonicity of a generalization of the positive part mapping which can be expressed in terms of the metric projection only. Although Németh characterized the positive cone of Hilbert lattices with the metric projection and ordering only [A.B. Németh, Characterization of a Hilbert vector lattice by the metric projection onto its positive cone, J. Approx. Theory 123 (2) (2003), pp. 295–299.], this has been done for the first time for subdual latticial cones in this article. We also note that the normal generating pointed closed convex cones for which the projection onto the cone is isotone are subdual latticial cones, but there are subdual latticial cones for which the metric projection onto the cone is not isotone [G. Isac, A.B. Németh, Monotonicity of metric projections onto positive cones of ordered Euclidean spaces, Arch. Math. 46 (6) (1986), pp. 568–576; G. Isac, A.B. Néemeth, Every generating isotone projection cone is latticial and correct, J. Math. Anal. Appl. 147 (1) (1990), pp. 53–62; G. Isac, A.B. Németh, Isotone projection cones in Hilbert spaces and the complementarity problem, Boll. Un. Mat. Ital. B 7 (4) (1990), pp. 773–802; G. Isac, A.B. Németh, Projection methods, isotone projection cones, and the complementarity problem, J. Math. Anal. Appl. 153 (1) (1990), pp. 258–275; G. Isac, A.B. Németh, Isotone projection cones in Eucliden spaces, Ann. Sci. Math Québec 16 (1) (1992), pp. 35–52].     

锥度量空间的若干拓扑性质

讨论锥度量空间的一些拓扑性质．主要讨论锥度量空间的邻域,开集和拓扑结构,以及锥度量空间中序列的收敛性．     

Cone metric spaces and fixed point theorems in diametrically contractive mappings

In this paper, some topological concepts and definitions are generalized to cone metric spaces. It is proved that every cone metric space is first countable topological space and that sequentially compact subsets axe compact. Also, we define diametrically contractive mappings and asymptotically diametrically contractive mappings on cone metric spaces to obtain some fixed point theorems by assuming that our cone is strongly minihedral.     

Common Fixed Points for a Countable Family of Quasi-Contractive Mappings on a Cone Metric Space with the Convex Structure

In this paper, we consider a countable family of surjective mappings {Tn}n∈N satisfying certain quasi-contractive conditions. We also construct a convergent sequence { Xn } n c∈Nby the quasi-contractive conditions of { Tn } n ∈N and the boundary condition of a given complete and closed subset of a cone metric space X with convex structure, and then prove that the unique limit x＂ of {xn}n∈N is the unique common fixed point of {Tn}n∈N. Finally, we will give more generalized common fixed point theorem for mappings {Ti,j}i,j∈N. The main theorems in this paper generalize and improve many known common fixed point theorems for a finite or countable family of mappings with quasi-contractive conditions.     

On Generalized Algebraic Cone Metric Spaces and Fixed Point Theorems

In this paper, the author first introduces the concept of generalized algebraic cone metric spaces and some elementary results concerning generalized algebraic cone metric spaces. Next, by using these results, some new fixed point theorems on generalized (complete) algebraic cone metric spaces are proved and an example is given. As a consequence, the main results generalize the corresponding results in complete algebraic cone metric spaces and generalized complete metric spaces.     

Common Fixed Points for Mappings with Quasi-Lipschitz Conditions on TVS-valued Cone Metric Spaces

A new unique common fixed point result for a pair of mappings satisfying certain quasi-Lipschitz type conditions on a topological vector space-valued cone metric space is obtained, and its particular forms and a more general form are given. Our main results generalize and improve some well-known recent results in the literature.     

A characterization of extended monotone metrics

Classical information geometry has emerged from the study of geometrical aspect of the statistical estimation. Cencov characterized the Fisher metric as a canonical metric on probability simplexes from a statistical point of view, and Campbell extended the characterization of the Fisher metric from probability simplexes to positive cone . In quantum information geometry, quantum states which are represented by positive Hermitian matrices with trace one are regarded as an extension of probability distributions. A quantum version of the Fisher metric is introduced, and is called a monotone metric. Petz characterized the monotone metrics on the space of all quantum states in terms of operator monotone functions. A purpose of the present paper is to extend a characterization of monotone metrics from the space of all states to the space of all positive Hermitian matrices on finite dimensional Hilbert space. This characterization corresponds quantum modification of Campbell’s work.     

For cones in Hilbert spaces, regularity is equivalent to self-duality

The theorem stating that a cone in a Hilbert space is regular if and only if it is self-dual is proved and applied to obtain new proofs of earlier results.Translated fromMatematicheskie Zametki, Vol. 64, No. 4, pp. 616–621, October, 1998.     

On the Additivity of the Minkowski Functionals

In this work, we investigate the additivity of the Minkowski functionals associated to a cone in a linear vector space. As an application we discuss the equivalence of the classical Caristi fixed point theorem in metric spaces and its vectorial version in cone metric spaces.     

Fixed point results on metric-type spaces

In this paper we obtain fixed point and common fixed point theorems for self-mappings defined on a metric-type space, an ordered metric-type space or a normal cone metric space. Moreover, some examples and an application to integral equations are given to illustrate the usability of the obtained results.