BCK和BCI—代数的映射

在ＢＣＫ－代数中引进了一个右映射和ＢＣＩ－代数中引进了一个弱左映射，并探讨它们的性质。从而推广了文［１］中大部分结果。主要结果是：如果Ｘ是一个ＢＣＫ－代数，Ｙ是一个正定关联ＢＣＫ－代数，则所有Ｘ到Ｙ的左映射的集合也构成一个正定关联ＢＣＫ－代数。     

广义Hammerstein型方程的存在定理

本文利用单调型强制映射满射性和逼近方法建立了广义Ｈａｍｍｅｒｓｔｅｉｎ型方程ｕ＋Ｋ（ｕ）Ｆ（ｕ）＝０解的存在性定理，这里对于实自反Ｂａｎａｃｈ空间Ｘ的共轭空间Ｘ^*的每个ｕ，Ｋ（ｕ）：Ｘ→Ｘ^*是线性映射，Ｆ：Ｘ^*→Ｘ是任一映射．所得结果推广了Ｓｃｈｉｌｉｎｇ，Ｓｒｉｋａｎｔｈ ａｎｄ Ｊｏｓｈｉ等相应的结果     

Gelfand-Naimark定理的非交换推广

本文指出C^*-代数是标准的,当且仅当,它等距*同构于本原C^*-代数连续场所定义的C^*-代数,从而给出了标准C^*-代数更为自然的定义。同时指出一般的C^*-代数,即使是在(Ⅰ)型的情况下,也未必满足正规性,这又解决了文献[1]中提出的一个问题。     

局部k-一致凸空间的对偶空间

本文证明了若Ｂａｎａｃｈ空间Ｘ是局部ｋ-一致凸的，则对每个ｘ∈Ｓ（Ｘ），ｆ∈Σ（ｘ）是Ｘ^*的ｋ－强光滑点，并得到局部ｋ－一致凸空间的几个性质．     

Loeb空间中的Radon-Nikodym导数

设υ及μ为定义在可测空间（Ｘ，Ｓ）上的有限测度．本文首先证明了若υ《μ（即υ关于μ绝对连续），则有Ｌ（^*Ｓ，^*μ）(?)Ｌ（＊Ｓ，υ）．进而证明了υ《μ当且仅当Ｌ（^*υ）《Ｌ（^*μ）并且ｄ（Ｌ（^*υ））／ｄ（Ｌ（^*μ））＝^０（^*（ｄυ／ｄμ））即Ｌｏｅｂ空间中的Ｒａｄｏｎ－Ｎｉｋｏｄｙｍ定理．本文按一种自然的方式定义了σ－有限测度空     

JC代数的乘子代数

本文用双中心子刻画了JC代数的乘子代数,并且研究了复C^*-代数的自伴部分的乘子代数生成的C^*-代数与原C^*-代数的乘子代数之间的关系,最后研究了JB代数的扩张.     

基础R0-代数的性质及在L*系统中的应用

研究了王国俊教授建立的模糊命题演算的形式演绎系统L^*和与之在语义上相关的R₀-代数,提出了基础R₀-代数的观点并讨论了其中的一些性质,在将L^*系统中的推演证明转化为相应的R₀-代数中的代数运算方面作了一些尝试,作为它的一个应用,证明了L^*系统中的模糊演绎定理。     

强Θ类算子生成的C*-代数及其K-理论

本文研究由强类算子T生成的C^*-代数,证明了C^*(T)的换子理想I(T)是一列*同构于C₀(Z⁰)上n阶矩阵代数的n齐次代数和的闭包,特别当T完全非正常时,I(T)与C₀(Z₀)K(l²)*同构。本文第二部分得到完全非正常强类算子的谱与其近似点谱相等的一些等价条件,并计算了由该类算子生成的C^*-代数的一些K群。     

自反BCK－代数

本文在ＢＣＫ－代数中引进稳定子的概念，并定义一类特殊的ＢＣＫ－代数─自反ＢＣＫ－代数，证明自反ＢＣＫ－代数的概念与半单ＢＣＫ－代数的概念是一致的，同时对于有限ＢＣＫ－代数还得到它是自反的一个充要条件。     

LSC(X,R*)上Way-Below关系的一个注

本文指出文献［１］中关于下半连续函数格ＬＳＣ（Ｘ,Ｒ^*）上Ｗａｙ－ｂｅｌｏｗ关系的一个结论是错误的,并且给出一个修正的命题及其证明．     

正定关联BCI—代数

本文是作者［１］和［２］的继续，引入了正定关联ＢＣＩ－代数的概念，并证明了：正定关联ＧＢＣＫ－代数类和Ｐ－半单ＢＣＩ－代数类是正定关联ＢＣＩ－代数类的真子类。     

基于L~*-格值逻辑上的BCK-代数中直觉不分明化理想

在L~*-格值逻辑的语义框架下,以L~*-格值上的Lukasiewicz蕴涵算子为工具定义了L~*-格值逻辑上的直觉不分明化BCK-代数的概念,将用集论所刻画的BCK-代数中理想、正定蕴涵理想和蕴涵理想等概念在L~*-格值谓词演算下给予了新的刻画,讨论了它们的性质及其关系,研究了这些理想与其同态象、同态原象之间关系,获得了同类理想之积仍为该类理想.     

The Semigroup Characterizations of Nil BCI-Algebras

In this paper, some characterizations of nil BCI-algebras X are given by disscusing the adjoint semigroup of X. Moreover, the definition of generalized positive implicative BCI-algebras is introduced and some properties are obtained.AMS Subject Classification (1991): 03G25, 06F35.The subject supported by the Educational Committee of Hebei.     

有条件(DS)的BCK-代数

在本文引入有条件（DS）,从而证明了有界关联DCK－代数与合正关联BCK－代数是一致的。     

Construction of quotient BCI(BCK)-algebra via a fuzzy ideal

The present paper gives a new construction of a quotient BCI(BCK)-algebraX/μ by a fuzzy ideal μ inX and establishes the Fuzzy Homomorphism Fundamental Theorem. We show that if μ is a fuzzy ideal (closed fuzzy ideal) ofX, thenX/μ is a commutative (resp. positive implicative, implicative) BCK (BCI)-algebra if and only if μ is a fuzzy commutative (resp positive implicative, implicative) ideal ofX. Moreover we prove that a fuzzy ideal of a BCI-algebra is closed if and only if it is a fuzzy subalgebra ofX. We show that if the period of every element in a BCI-algebraX is finite, then any fuzzy ideal ofX is closed. Especially, in a well (resp, finite, associative, quasi-associative, simple) BCI-algebra, any fuzzy ideal must be closed.     

空间的几种超投影性质及其局部化

讨论Banach空间几种超投影性质(及其相应的局部化性质)之间的关系,证明了在Banach空间X自反的条件下,X是l_p-次投影空间的充要条件是X^*是l_p-超投影空间,X是局部l_p-次投影空间的充要条件是X^*是局部l_p-超投影空间,以及X是局部次投影空间的充要条件是X^*是局部超投影的。其中1/p+1/q=1(p>1,q>1)。     

Weak* derived sets of sets of linear functionals

For a Banach space X the w^*-sequential closure operator in the adjoint space is, in general, not the topological closure operator. That is, it may happen that the w^*-sequential closure of a subspace T of X^* is not w^*-sequentially closed. The possible length of the chain of repeated w^*-sequential closures of a subspace of X^* in dependence on the dimension of X^**/X is investigated.Translated from Matematicheskie Zametki, Vol. 23, No. 4, pp. 607–616, April, 1978.In conclusion, the author thanks M. I. Kadets for the formulation of the problem and assistance with the article.     

On the characteristic of sets in the space conjugate to a normed structure

Let (E, ∥ · ∥_E) be a normed space, E^* its conjugate, and M a linear subset in E^*. The number is called the characteristic of the set M. In this paper we establish a relationship in normed structures between the semicontinuous properties of the norm and the characteristics of certain subsets in the conjugate space. For example, the following is a valid proposition. Let (X, ∥ · ||_X) be a KN-space. Then in order that ∥ · ∥_X be semicontinuous on X it is necessary and sufficient that for each intervally-complete norm p on X the set (X, ∥ · ∥_X)^* ∩ (X, p)^*, i.e., the set of all functionals linear on X, simultaneously continuous with respect to both the norm ∥ · ∥_X and the norm p, have characteristic one in the space (X, ∥ · ∥_X).     

n ‐fold filters in BL‐algebras

In this paper we introduce n ‐fold (positive) implicative basis logic and the related algebras called n ‐fold (positive) implicative BL‐algebras. Also we define n ‐fold (positive) implicative filters and we prove some relations between these filters and construct quotient algebras via these filters. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Characterizations of right dense languages

Let X be an alphabet contains more than one letter and let X^* be the free monoid generated by X. A language S≤X^* is right dense if uX^*∩S≠ϕ for all u∈X^*. The purpose of this paper is to give characterizations of right dense languages. This research has been supported by Grant NSC74-0208-M005-01 R.O.C.