Pseudolinear fuzzy mappings

Two classes of fuzzy mappings, called pseudolinear and η-pseudolinear fuzzy mappings are introduced by relaxing the definitions of pseudo-convex and pseudo-invex fuzzy mappings. First, some characterizations of pseudolinear and η-pseudolinear fuzzy mappings are obtained. Then, characterizations of the solution sets of pseudolinear and η-pseudolinear fuzzy programs are derived.     

Fuzzy映射与F基数

本文定义了从一个Ｆｕｚｚｙ集到另外一个Ｆｕｚｚｙ集的映射，称之为Ｆｕｚｚｙ映射，它不同于以往人们习惯用的“模糊映射”；给出了Ｆｕｚｚｙ映射的等价条件并研究了Ｆｕｚｚｙ映射的性质；基于这样的Ｆｕｚｚｙ映射定义了Ｆｕｚｚｙ映集的基数简称为Ｆ基数，讨论了它的基本性质；最后说明了Ｆ基数对于连续统假设的影响。     

A note on semi-open sets in fuzzy topological spaces

Concepts of semi-T_i (i = 0, 1, 2) spaces and semi-R_i (i = 0, 1) spaces are introduced and some fuzzy topological properties are investigated under the above mentioned axioms. Some mappings involving semi-open sets on fuzzy topological spaces are also introduced and investigated.     

Fixed points of fuzzy contractive and fuzzy locally contractive maps

We establish some fixed point theorems for fuzzy contractive and fuzzy locally contractive mappings on a compact metric space with the d_∞-metric for fuzzy sets. Our results generalized well-known classical results of Edelstein.     

Commutation in vector spaces over division rings with a conjugation

We analyze some commutation properties of the sets of mappings of a vector space X over a division ring K with a conjugation j which are relevant when studying symmetries in quantum mechanics and in elementary-particle physics. The first part of the paper is devoted to the “linear-antilinear centralizer” $\text{U}$^c, i.e. to the group of the linear and antilinear (j-semilinear) invertible mappings which commute with a given set $\text{U}$ of mappings of X. Some nontrivial results which connect properties of $\text{U}$ with properties of $\text{U}$^c are obtained, and a classification of the sets of mappings of X is found by means of purely algebraic techniques. This classification is more detailed than that usually adopted by physicists. The second part of the paper is devoted to the ?-linear commutant $\text{U}$′^λ, i.e. to the set of mappings of X which commute with $\text{U}$ and which are linear with respect to the j-invariant subring ? of K. We investigate the structure of $\text{U}$′^λ in connection with the structure and some of the properties of $\text{U}$. In the third part, we show how the results obtained in the preceding sections simplify when the division ring K is of type II (according to a classification introduced in an earlier work). Finally, we illustrate with simple examples in one- and two-dimensional vector spaces all the cases which can occur.     

On the stable containment of two sets

This paper studies the stability of the set containment problem. Given two non-empty sets in the Euclidean space which are the solution sets of two systems of (possibly infinite) inequalities, the Farkas type results allow to decide whether one of the two sets is contained or not in the other one (which constitutes the so-called containment problem). In those situations where the data (i.e., the constraints) can be affected by some kind of perturbations, the problem consists of determining whether the relative position of the two sets is preserved by sufficiently small perturbations or not. This paper deals with this stability problem as a particular case of the maintaining of the relative position of the images of two set-valued mappings; first for general set-valued mappings and second for solution sets mappings of convex and linear systems. Thus the results in this paper could be useful in the postoptimal analysis of optimization problems with inclusion constraints.      

Towards fuzzy differential calculus part 1: Integration of fuzzy mappings

This paper deals with fuzzy-set-valued mappings of the real line, and more particularly focuses on mappings from the real line to the set of convex normal fuzzy sets of the real line. These mappings can also be viewed as fuzzy relations. Using Zadeh's extension principle, the integral of such fuzzy mappings over a crisp interval is defined. Provided a special analytical representation of the fuzzy mapping, the practical computation of such an integral is shown to be easy. Practically speaking, it yields the fuzzy surface of a fuzzily-bounded area.     

Über analytisch abhängige holomorphe und meromobphe Abbildungen

We discuss the conceptions of analytic dependence, strict analytic dependence, spaces of level sets and complex bases of holomorphic mappings and their relationship. For instance, a theorem of the following type is proved: Let X be a normal complex space, let be holomorphic mappings, which are analytically related (i.e. depends analytically on and depends analytically on). Let be maximal (i.e. majorizes every holomorphic map which is strictly analytically dependent on) and let be strongly maximal (i.e. majorizes every holomorphic map which depends analytically on). Then Z^* is a proper modification of, if is proper or nowhere degenerated.     

凸直觉模糊映射

在模糊数、凸模糊映射和凸直觉模糊集定义基础上,给出了直觉模糊数及其序的定义,给出了凸直觉模糊映射的定义并讨论其有关性质,在此基础上,研究了凸直觉模糊规划问题。     

Kantorovich’s Fixed Point Theorem and Coincidence Point Theorems for Mappings in Vector Metric Spaces

Set-Valued and Variational Analysis - The fixed points and coincidence points of mappings of v-metric spaces, i.e., sets on which a vector metric is defined, are investigated. The values of such a...     

Regularly open sets in fuzzy topological spaces

This paper is devoted to the study of the role of fuzzy regularly open sets. We prove some properties of fuzzy almost continuous mappings and define fuzzy almost open mappings. We prove that under a fuzzy almost continuous and fuzzy almost open map, the inverse image of a fuzzy regularly open set is fuzzy regularly open. Further we define a new type of fuzzy separation axioms, fuzzy almost separation axioms. It is interesting that there are some deviations in the behaviour of these axioms as compared to those in general topology. For example, in a fuzzy almost T₁ space not every fuzzy singleton is δ-closed. Also a fuzzy space which is fuzzy almost as well as fuzzy almost T₀ is fuzzy almost regular. While in general topology we have to take an almost T₂ space in place of almost T₀ space.     

Fuzzy differential equations

This paper deals with fuzzy-set-valued mappings of a real variable whose values are normal, convex, upper semicontinuous and compactly supported fuzzy sets in Rⁿ. We study differentiability and integrability properties of such functions and give an existence and uniqueness theorem for a solution to a fuzzy differential equation.     

集值映象的图象拓扑与不动点的通有稳定性

本文进一步研究了上半连续集值映象不动点的稳定性问题,在集值映象的图象拓扑的意义下,我们证明了不动点的通有稳定性,也就是说,在Baire分类的意义下,绝大多数的映象具有本质不动点.     

Bisimulations for fuzzy automata

Bisimulations have been widely used in many areas of computer science to model equivalence between various systems, and to reduce the number of states of these systems, whereas uniform fuzzy relations have recently been introduced as a means to model the fuzzy equivalence between elements of two possible different sets. Here we use the conjunction of these two concepts as a powerful tool in the study of equivalence between fuzzy automata. We prove that a uniform fuzzy relation between fuzzy automata A and B is a forward bisimulation if and only if its kernel and co-kernel are forward bisimulation fuzzy equivalence relations on A and B and there is a special isomorphism between factor fuzzy automata with respect to these fuzzy equivalence relations. As a consequence we get that fuzzy automata A and B are UFB-equivalent, i.e., there is a uniform forward bisimulation between them, if and only if there is a special isomorphism between the factor fuzzy automata of A and B with respect to their greatest forward bisimulation fuzzy equivalence relations. This result reduces the problem of testing UFB-equivalence to the problem of testing isomorphism of fuzzy automata, which is closely related to the well-known graph isomorphism problem. We prove some similar results for backward-forward bisimulations, and we point to fundamental differences. Because of the duality with the studied concepts, backward and forward-backward bisimulations are not considered separately. Finally, we give a comprehensive overview of various concepts on deterministic, nondeterministic, fuzzy, and weighted automata, which are related to bisimulations.     

Fixed points for fuzzy mappings

In this paper the problem of the existence and computation of fixed points for fuzzy mappings is approached. A fuzzy mapping R over a set X is defined to be a function attaching to each x in X a fuzzy subset R_χ of X. An element x of X is called fixed point of R iff its membership degree to R_χ is at least equal to the membership degree to R_χ of any y?X, i.e. R_χ(χ)? R_χ(y)(?y?X). Two existence theorems for fixed points of a fuzzy mapping are proved and an algorithm for computing approximations of such a fixed point is described. The convergence theorem of our algorithm is proved under the restrictive assumption that for any x in X, the membership function of R_χ has a ‘complementary function’. Examples of fuzzy mappings having this property are given, but the problem of proving general criteria for a function to have a complementary remain open.     

Approximation of fixed points and variational solutions for pseudo-contractive mappings in banach spaces

Let K be a nonempty, closed and convex subset of a real reflexive Banach space E which has a uniformly Gâteaux differentiable norm. Assume that every nonempty closed convex and bounded subset of K has the fixed point property for nonexpansive mappings. Strong convergence theorems for approximation of a fixed point of Lipschitz pseudo-contractive mappings which is also a unique solution to variational inequality problem involving ?-strongly pseudo-contractive mappings are proved. The results presented in this article can be applied to the study of fixed points of nonexpansive mappings, variational inequality problems, convex optimization problems, and split feasibility problems. Our result extends many recent important results.     

On the weak isometries of the Boolean cube

The p-weak isometries of the Boolean cube are considered, i.e., the mappings of the cube onto itself which preserve a fixed distance p. Some necessary and sufficient conditions are obtained for coincidence of the group of p-weak isometries with the group of standard isometries (automorphisms of the cube).     

图闭模糊映射与闭模糊映射的关系研究

给出图闭模糊映射和闭模糊映射的关系:图闭模糊映射一定是闭模糊映射;若闭模糊映射是上半连续的则它也是图闭模糊映射.     

Determination of the threshold value β of variable precision rough set by fuzzy algorithms

In the past, the choices of β values to be applied to find the β-reducts in VPRS for an information system are somewhat arbitrary. In this study, a systematic method which bridges the fuzzy set methodology and probabilistic approach of RS to solve the threshold value β determination problem in variable precision rough sets (VPRS) is proposed. Different from the existing probabilistic methods, the proposed method relies on the fuzzy membership degrees of each attribute of the objects to calculate β. The proposed method gives the membership degrees and fuzzy aggregation operators the probabilistic interpretations. Based on the probabilistic interpretations, the threshold value β of VPRS is directly derived from fuzzy membership degree by Implication Relations and Fuzzy Algorithms, in which the membership degrees are obtained by the standard Fuzzy C-means method. The argument is that errors of system classification would occur in the fuzzy-clustering phase prior to information classification, therefore the threshold value β should be constrained by the probability of belongingness of an object to the fuzzy clusters, i.e., through the values of membership functions. A few examples are given in the paper to demonstrate the differences with other β-determining methods.