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1.
在L-拓扑空间中引入了相对S*-紧性的概念,证明了相对S*-紧性是相对闭遗传的、弱同胚不变的和L-好的推广等性质,并证明了相对S*-紧性的T ychonoff定理是成立的。  相似文献   

2.
在L-拓扑空间中基于S*-紧性,并借助于拟开L-集合引入了PS*-紧性概念并研究了它的一系列性质,证明了PS*-紧性是L-好的推广.  相似文献   

3.
在L-拓扑空间中引入相对Sβ-紧性的概念,得到了它的一些性质,如它是L-好的推广,对闭子集遗传,被连续的广义Zadeh型函数所保持.此外,给出了相对Sβ-紧性的网式刻画.  相似文献   

4.
在L-拓扑空间中引入半Sβ-紧性,这种紧性是针对任意L-模糊子集定义的,它是Sβ-紧性的推广。研究半Sβ-紧性的性质,如一个半Sβ-紧集与一个半闭集的交仍为半Sβ-紧的;半Sβ-紧性在不定映射下保持不变;由分明拓扑空间(X,τ)拓扑生成的L-拓扑空间(LX,ωL(τ))是半Sβ-紧的当且仅当(X,τ)是半紧的。此外,还给出了半Sβ-紧性的网式刻画。  相似文献   

5.
研究了L-拓扑空间的相对α-紧集.基于α-紧性,在L-拓扑空间中引入相对α-紧性的概念,得到了它的一些性质,如它是L-好的推广,对α-闭子集遗传,被α-irresolute的广义Zadeh型函数所保持等.  相似文献   

6.
在L-拓扑空间中引入相对β-紧性的概念,得到了它的一些性质,如它是L-好的推广,对β-闭子集遗传,被Mβ-连续的广义Zadeh型函数所保持等.  相似文献   

7.
在L-拓扑空间中引入相对Nβ-紧性的概念,得到了它的一些性质,如它是L-好的推广,对子集遗传,被连续的广义Zadeh型函数所保持等.  相似文献   

8.
拓扑分子格的S紧性和S次紧性   总被引:2,自引:0,他引:2  
利用半开元等半拓扑概念在拓扑分子格中引入S紧性与S次紧性,给出了它们的刻画,推广了文[1]中的紧性与次紧性,证明了拓扑分子格的S紧性,S次紧性,STi分离性(i=-1,0,1,2)与STi^*分离性(i=0,1,2)为半拓扑性质。  相似文献   

9.
在L-保序算子空间中引入ω-仿紧性,证明它是L-好的推广,它对ω-闭子集遗传、ω-紧的L-保序算子空间和ω-仿紧空间的积空间是仿紧的.  相似文献   

10.
本文在文献[4]的基础上,研究了L-拓扑空间的局部Nβ-紧性.借助于完全Nβ-紧集和强邻域,定义了L-拓扑空间的局部Nβ-紧性,证明了它是闭可遗传的、有限可乘的、且在连续开满的L值Zadeh型函数下保持不变,说明了它是一种L-好的推广性质.  相似文献   

11.
Zadeh[1]定义了在概率清晰和事件模糊条件下,模糊事件的概率表示.不过,用[1]表示概率,求解繁杂且困难.为此,利用结构元理论,定义了模糊数事件概率的表达式.不仅证明其与经典定义等价,且证明了模糊数事件复合表达形式.最后,给出了关于模糊数不等式的概率的表达式.通过算倒可看出,运用本方法求解模糊数事件概率比较简捷.  相似文献   

12.
Two converse theorems related to a family of homogeneous homothetic bodies and connected to the theory of the Newtonian field are proved. In both of them the function characterising the attraction is unknown and it is demonstrated that this function in the first theorem is given by the one characterising the Newtonian field and in the second theorem it is given by this latter function with the addition of a linear function of distance. A second unknown function appears in the second theorem and it is proved that it is a linear function of the volume of the bodies. Moreover, in both the theorems it is proved that the unknown shape of the bodies must be spherical.

The conjecture is made that the two theorems are still true without the hypothesis that the unknown function characterising the attraction has a pole.

The full significance of the two theorems is briefly illustrated by the application of the second theorem to the case of a finite homogeneous fluid, the behaviour of which is isotropic with respect to an element of it. Among other results, it is found that the shape of the fluid is necessarily spherical and the forces at a distance which are exerted among the elements of the fluid are expressed by Newton's Law of gravitation.

AMS Classification 31B20, 31B99, 76A02, 76A99  相似文献   

13.
A necessary condition for a diagram to be a Schlegel diagram of some convex polytope is that it be invertible, that is, it can be realized with any facet as the outside facet. In this paper we prove that it is not a sufficient condition by constructing a 3-diagram that is invertible but is not isomorphic to a Schlegel diagram of any 4-polytope. Research supported by NSF Grant #NSF MCS-07466.  相似文献   

14.
在模糊数的结构元表示B~=f(E)中,要求f(x)在[-1,1]上单调,将f(x)扩展为[-1,1]上的连续函数,在证明f(E)是有界模糊数的基础上,给出了相应模糊数的隶属函数表达形式。由于单调性质在模糊数的运算表示中具有重要作用,还得出非单调连续函数f(x)的E-等价函数概念,并给出了E-等价函数的求法。对于算例,用结构元理论是无法求解的,用本文的方法给出解答。  相似文献   

15.
文[13]曾证明Erceg伪度量与史福贵提出的点式伪度量等价.本文指出[13]中的定理1是错误的,进而指出Erceg伪度量与点式伪度量是不等价的.  相似文献   

16.
In this paper we describe a one-variable Mal'cev-like condition satisfied by any locally finite minimal variety. We prove that a locally finite variety is minimal if and only if it satisfies this Mal'cev-like condition and it is generated by a strictly simple algebra which is nonabelian or has a trivial subalgebra. Our arguments show that the strictly simple generator of a minimal locally finite variety is unique, it is projective and it embeds into every member of the variety. We give a new proof of the structure theorem for strictly simple abelian algebras that generate minimal varieties.

  相似文献   


17.
In [6],it is proved that Erceg's pseudo-metric and pointwise pseudo-metric presented by Shi are equivalent.In this paper,it is proved that Theorem 1 in[6] is wrong.Further it is proved that Erceg's pseudo-metric and pointwise pseudo-metric are not equivalent in the sense of topology.  相似文献   

18.
Two of the main forms of anti-scepticism in the contemporary literature—namely, neo-Mooreanism and attributer contextualism—share a common claim, which is that we are, contra the sceptic, able to know the denials of sceptical hypotheses. This paper begins by surveying the relative merits of these views when it comes to dealing with the standard closure-based formulation of the sceptical problem that is focussed on the possession of knowledge. It is argued, however, that it is not enough to simply deal with this version of the sceptical challenge, since there is a more fundamental sceptical problem underlying the standard closure-based sceptical argument that can be expressed in terms of the evidential basis of our beliefs. Whilst it is argued that neo-Mooreanism has a slight edge over attributer contextualism when it comes to dealing with the closure-based formulation of the sceptical problem, it is claimed that this view is in an ever stronger dialectical position when it comes to the more pressing evidential formulation of the sceptical problem. It is shown that this is so even if one adapts the attributer contextualist thesis along the lines suggested by Michael Williams and Ram Neta so that it is explicitly designed to deal with the evidential variant of the sceptical problem.  相似文献   

19.
Charles T. Zahn has recently proposed a new and promising statement that encourages structured thinking and that may also be said to make programming become documentation. D. E. Knuth has suggested that this statement may be of importance in future languages, and it has been thoroughly discussed in the literature. However, it seems that the statement is not properly suited for problems requiring nested constructs, and it is argued that this is caused by the long implicit jumps in the statement. It is also shown that by introducing an event-variable and by permitting different events to share actions, the statement will become even more useful. A modified statement is proposed and demonstrated on a number of standard ill-structured algorithms that normally call for the use of GOTOs.  相似文献   

20.
定义了L-拓扑空间的局部半紧性,证明了这种局部半紧性是L-好的推广,是半闭可遗传的,在irresolute、开的、满的L值Zadeh型函数下保持不变.  相似文献   

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