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1.
本文证明了在弱诱导空间与强Hausdorff空间,超F紧性、良紧性、强F紧性、F紧性等价;构造了一个满层Hausdorff良紧而非强Hausdorff非超F紧的反例,否定地回答了文献[1]中的公开问题5.4.10和6.4.31;给出了Hausdorff良紧空间是超F紧的若干充要条件。  相似文献   

2.
 在L-fuzzy拓扑空间中引入了相对仿紧性的概念,研究了相对仿紧集和相对仿紧子空间的性质,给出了弱诱导的F拓扑空间的子空间相对仿紧的等价条件.  相似文献   

3.
仿紧性是模糊拓扑学中的重要概念.在LF闭包空间中仿紧性的基础上,介绍了层仿紧性,并刻画了其基本特征.研究了LF闭包空间中层仿紧性的性质:对Cech闭包算子的像集可遗传,与F仿紧集的乘积是层仿紧集,是"L-好的推广",具有LF弱同胚不变性.  相似文献   

4.
在L-拓扑空间中引入F*-仿紧性,证明了这种仿紧性具有一些好的性质,比如L-good extension,闭遗传,及弱同胚不变性,F紧集与F*-仿紧集的乘积是F*-仿紧集,同时证明了F*-仿紧性可以增强分离性。最后讨论了与其他仿紧性之间的关系。  相似文献   

5.
讨论了各种可数性和分离性与λ-截拓扑的关系.特别是,若(L~X,δ)是λ-弱诱导空间,则(L~X,δ)是Hausdorff空间或强Hausdorff空间,当且仅当λ-截拓扑空间(X,ι_λ(δ))是Hausdorff空间,因此对λ-弱诱导空间来说,Hausdorff分离性与强Hausdorff分离性是等价的;又若(L~X,δ)是满层的λ-弱诱导空间,则(L~X,δ)是ST_1的(ST_2的),当且仅当λ-截拓扑空间(X,ι_λ(δ))是T_1的(T_2的),于是对满层的λ-弱诱导空间来说,ST_2分离性与强Hausdorff分离性及Hausdorff分离性是等价的.  相似文献   

6.
L-fuzzy 拓扑空间的相对强F紧性   总被引:1,自引:0,他引:1  
定义了L fuzzy拓扑空间的相对强F紧性,给出了它的一些等价刻划,研究了相对强F紧性与强F紧性的关系.讨论了相对强F紧性的一系列性质,证明了相对强F紧空间是相对闭遗传的、弱同胚不变的、L 好的推广性质,并且相对强F紧空间的Tychonoff乘积定理是成立的.  相似文献   

7.
LF闭包空间的仿紧性   总被引:1,自引:0,他引:1  
在LF闭包空间中,引入α-包域、α--包域族等概念,并以此定义了F紧集、F仿紧集和F乘积空间.给出了F紧集和F仿紧集的特征刻画.证明了F紧集是F仿紧集,F仿紧性是F可乘性.  相似文献   

8.
定义了Lfuzzy拓扑空间中的相对F紧性,给出了它的一些等价刻画.证明了:相对F紧性是相对闭遗传 的、弱同胚不变的、L好的推广性质,并且诱导的相对F紧空间的乘积空间是相对F紧空间.最后研究了相对F 紧性与其他相对紧性的关系.  相似文献   

9.
利用SRθ-闭集定义了SRθ-强F紧集和SRθ-强F紧空间,讨论了SRθ-强F紧集的性质,得出SRθ-强F紧性是弱同胚不变性和SRθ-强F紧空间中每个θ-闭集都是SRθ-强F紧集.  相似文献   

10.
本文旨在解决与L—fuzzy拓扑空间的紧致性有关的如下三个问题:(1)建立超F紧的网刻划。(2)寻找Hausdorff良紧空间是超F紧的充要条件。(3)讨论L-fuzzy子集的良紧性和强F紧性在整体性质上的差异。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

20.
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