Topological Hypergroups in the Sense of Marty

In this paper, we introduce the concept of topological hypergroups as a generalization of topological groups. A topological hypergroup is a nonempty set endowed with two structures, that of a topological space and that of a hypergroup. Let (H, ○) be a hypergroup and (H, τ) be a topological space such that the mappings (x, y) → x ○ y and (x, y) → x/y from H × H to 𝒫*(H) are continuous. The main tool to obtain basic properties of hypergroups is the fundamental relation β*. So, by considering the quotient topology induced by the fundamental relation on a hypergroup (H, ○) we show that if every open subset of H is a complete part, then the fundamental group of H is a topological group.

It is important to mention that in this paper the topological hypergroups are different from topological hypergroups which was initiated by Dunkl and Jewett.     

基于超群的粒计算理论

首次将代数中的超群理论应用于粒计算研究之中。首先,引入正规超群和强正规超群的定义,证明了正规超群可由强正规超群生成;然后将粒计算商空间模型(X,f,T)中的T取为超群结构,利用超群同态证明了在模型(X,f,T)中,x与y在同一条路径上当且仅当在商空间模型([X],[f],[T])中,[x]与[y]在同一条路径上;并进一步证明了:若X与Y为超群同态的,则它们导出的商空间也是超群同态的。其次,我们研究了正规超群与可能性理论中的备域、超群与Paw lak近似空间及超群与拓扑空间的联系。指出:(1)强正规超群与备域是等价的;(2)强正规超群与Paw lak近似空间是等价的;(3)利用超群可定义集合的上、下近似,并利用集合的上、下近似刻画了超群同态;(4)强正规超群可由拓扑空间生成,正规超群可由拓扑空间生成的强正规超群生成;(5)可能性理论中的备域与Paw lak近似空间是等价的,且备域恰好是近似空间中所有可定义集合的全体。我们的研究表明:可能性理论中的备域与Paw lak的近似空间可利用正规超群来刻画。因此超群理论可用于粒计算的研究中。     

Relationship between Rings and Hyperrings by Using the Notion of Fundamental Relations

In the theory of hyperrings, fundamental relations make a connection between hyperrings and ordinary rings. The fundamental relation α on hyperrings is studied by Davvaz and Vougiouklis in Communications in Algebra [8 Davvaz , B. , Vougiouklis , T. ( 2007 ). Commutative rings obtained from hyperrings (H _v -rings) with α*-relations . Comm. Algebra 35 ( 11 ): 3307 – 3320 .[Taylor &; Francis Online], [Web of Science ®] , [Google Scholar]]. Now, in this article, we obtain more results about this relation. In particular, we determine necessary and sufficient conditions such that the relation α is transitive.     

On α-Relation and Transitivity Conditions of α

The main tools in the theory of hyperstructurs are the fundamental relations. The fundamental relation on hyperring was introduced by Vougiouklis at the fourth AHA congress (1990). The fundamental relation on a hyperring is defined as the smallest equivalence relation so that the quotient would be the ring. Note that, generally, the commutativity in the ring are not assumed. In this article, we introduce a new strongly regular equivalence relation on hyperring so that the quotient is a commutative ring. Also we state the condition that is equivalent with the transitivity of this relation and finally we characterize the complete hyperring (with the fundamental relation as commutative).     

Binary Relations on Ternary Semihypergroups

Ternary semihypergroups are algebraic structures with one associative hyperoperation. The main propose of this article is to study binary relations on ternary semihypergroups and study some basic properties of compatible relations on them. In particular, we analyze the ternary hypergroup associated with a binary relation.     

超图的最优标号与特征值

研究超图的标号性质,首先利用拉普拉斯张量的第二小和最大特征值给出4一致超图的带宽和与割宽的上下界;其次构造与超图对应的简单图,通过其拉普拉斯矩阵的特征值给出超图带宽的下界.     

Characterization of Operators on the Dual of Hypergroups which Commute with Translations and Convolutions

For a locally compact group G, L^1 (G) is its group algebra and L^∞(G) is the dual of L^1 (G).Lau has studied the bounded linear operators T:L^∞(G)→L^∞(G) which commute with convolutions and translations. For a subspace H of L^∞(G), we know that M(L^∞(G),H), the Banach algebra of all bounded linear operators on L^∞(G) into H which commute with convolutions, has been studied by Pyre and Lau. In this paper, we generalize these problems to L(K)^*, the dual of a hypergroup algebra L(K) in a very general setting, i.e. we do not assume that K admits a Haar measure. It should be noted that these algebras include not only the group algebra L^1(G) but also most of the semigroup algebras.Compact hypergroups have a Haar measure, however, in general it is not known that every hypergroup has a Haar measure. The lack of the Haar measure and involution presents many difficulties; however,we succeed in getting some interesting results.     

Commutative Rings Obtained from Hyperrings (H v -rings) with α∗-Relations

The main tools in the theory of hyperstructues are the fundamental relations. The fundamental relation on a hyperring was introduced by Vougiouklis at the fourth AHA congress. The fundamental relation on a hyperring (H _v -ring) is defined as the smallest equivalence relation so that the quotient would be the (fundamental) ring. Note that the commutativity with respect to both sum and product in the (fundamental) ring are not assumed. Now, in this article we would like the (fundamental) ring to be commutative with respect to both sum and product, that is, the fundamental ring should be an ordinary commutative ring. Therefore we introduce a new strongly regular equivalence relation on hyperrings (H _v -rings). If we consider this relation on a hperring (H _v -ring), then the set of quotients is a commutative ring. Some properties of such rings are investigated.     

On the Laplacian Eigenvalues and Metric Parameters of Hypergraphs

The aim of this paper is to generalize some concepts and recent results of the algebraic graph theory in order to investigate and describe, by algebraic methods, the properties of some combinatorial structures. Here we introduce a version of "Laplacian matrix" of a hypergraph and we obtain several spectral-like results on its metric parameters, such as the diameter, mean distance, excess, bandwidth and cutsets.     

On the α-spectra of Uniform Hypergraphs and Its Associated Graphs

For 0 ≤α 1 and a k-uniform hypergraph H, the tensor A_α(H) associated with H is defined as A_α(H) = αD(H) +(1-α)A(H), where D(H) and A(H) are the diagonal tensor of degrees and the adjacency tensor of H, respectively. The α-spectra of H is the set of all eigenvalues of A_α(H) and the α-spectral radius ρ_α(H) is the largest modulus of the elements in the spectrum of A_α(H). In this paper we define the line graph L(H) of a uniform hypergraph H and prove that ρ_α(H) ≤■ρ_α(L(H)) + 1 + α(Δ-1-δ~*/k), where Δ and δ~* are the maximum degree of H and the minimum degree of L(H), respectively. We also generalize some results on α-spectra of G~(k,s), which is obtained from G by blowing up each vertex into an s-set and each edge into a k-set where 1 ≤ s ≤ k/2.     

Hypergroups and invariant complemented subspaces

Let K   be a hypergroup with a Haar measure. The purpose of the present paper is to initiate a systematic approach to the study of the class of invariant complemented subspaces of _L∞(K)$L_{\infty }(K)$ and _C0(K)$C_0(K)$, the class of left translation invariant w^?$w^{?}$-subalgebras of _L∞(K)$L_{\infty }(K)$ and finally the class of non-zero left translation invariant C^?$C^{?}$-subalgebras of _C0(K)$C_0(K)$ in the hypergroup context with the goal of finding some relations between these function spaces. Among other results, we construct two correspondences: one, between closed Weil subhypergroups and certain left translation invariant w^?$w^{?}$-subalgebras of _L∞(K)$L_{\infty }(K)$, and another, between compact subhypergroups and a specific subclass of the class of left translation invariant C^?$C^{?}$-subalgebras of _C0(K)$C_0(K)$. By the help of these two characterizations, we extract some results about invariant complemented subspaces of _L∞(K)$L_{\infty }(K)$ and _C0(K)$C_0(K)$.     

可拓集合上的关系

本文给出可拓集合Ｘ到Ｙ上的关系Ｒ的概念，并讨论了可拓集合关系Ｒ的一般性质。     

A Procedure for Decision Making Based on Incomplete Fuzzy Preference Relation

In this paper, we investigate the decision making problem based on fuzzy preference relation with incomplete information. We first introduce incomplete fuzzy preference relation and present some of its desirable properties. We then develop a system of equations. Based on this system of equations, we propose a procedure for decision making based on incomplete fuzzy preference relation, and finally, a numerical example is presented to illustrate the proposed procedure.     

基于灰色关联分析和主成分分析组合权重的确定方法研究

为了提高综合评价模型中权重的准确性和客观性,以主成分分析法和灰色关联分析法为基础,建立了组合权重模型,从而修正了灰色关联分析法和主成分分析法在确定权重过程中的缺陷,为综合评价体系中权重的确定提出一种新的思路.     

基于关联度的灰色模糊综合评判

针对被评判对象的特点,根据灰色模糊数学的理论,将隶属度和灰度综合起来表示灰色模糊数,并结合灰色关联度的应用,建立了基于关联度分析的灰色模糊综合评判的数学模型,此方法能使评判结果更加客观可信.     

基于熵权与优势关系的教学效果评价方案

为了提高教学效果评价的质量,利用熵权方法来确定评价指标的权向量,进一步结合优势关系建立一种综合排序方法,并应用文献(中国卫生统计,2009,26(3)314-316.)的一个实例表明方法是有效和可行的.     

基于粗糙集理论的相关关系预测方法研究

本基于粗糙集理论给出了对象与规则可信度的概念，提出了一种经济系统中相关关系预测法。利用信息熵的概念，评价因素的重要程度和约简因素，由此提取基本相关规则。在对象与规则之间的可信度基础上，建立了预测模型。与传统的回归预测法比较，这个方法不需要进行相关性判断、模型识别和检验，它直接从数据出发，在不损失信息的条件下约简冗余因素，寻找经济指标与影响因素之间的相关关系，能同时处理定性、定量因素以及不确定因素。算例计算说明了所提方法的有效性。     

特殊集上素变数方程的解

令n=e_0+e_12+…+e_k2~k,其中e_j=0,1(j=0,…,k)表示自然数n的二进制展开式,N_0表示二进制展开式中项数为偶数的自然数的集合.分别给出了这个特殊集上素变数方程p_1+p_2+p_3~k=N和p_1+p_2~2+p_3~2+p_4~2=N解的个数的渐近公式.     

在带边紧致流形上的Einstein关系

本文中建立了Ｒｉｅｍａｎｎ流形的紧区域上反射扩散过程的Ｅｉｎｓｔｅｉｎ关系，并对具有斜反射的一维随机微分方程给出了这种关系的显式。     

等价关系的判定及性质

设R是集合A上的二元关系,要判定R在A上是否是等价关系,一般来讲,只能从定义出发,当R包含的序偶较多时,从定义出发又比较难于判定.从关系矩阵出发,给出一种判定方法,并讨论等价关系的矩阵性质.