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1.
拓扑系统的分离性   总被引:5,自引:0,他引:5  
拓扑系统是目前最广泛的拓扑研究对象之一,它以点集拓扑空间,Locale的空间化,模糊拓扑空间与拓扑分子格为特例,它可以用来研究 计算机程序语言的指称语义的Domain理论。作者从拓扑学的角度研究了拓扑系统的分离性,得到了关于拓扑系统分离性刻画的几个定理。  相似文献   

2.
文斌  宋丽艳 《佳木斯大学学报》2003,21(3):275-276,314
在集值映射空间中引入了四种图象拓扑,给出它们之间的关系,并在点紧致连续映射空间上证明了其中两种拓扑之间的等价关系.  相似文献   

3.
讨论了由映射族确定预拓扑空间的一些方法,定义了预拓扑空间范畴preTOP,并证明预拓扑空间范畴preTOP具有乘积、余积.  相似文献   

4.
Scott连续映射的分析式与分层次式刻划及应用   总被引:1,自引:1,他引:0  
首先建立了拓扑空间到连续格的Scott连续映射的分析式与层次式刻划。共次利用这些刻划得到了连续格的分析式与层次式刻划,改进了有关作者的完全分配格的分析式刻划。  相似文献   

5.
狄尼(Dini)定理的推广   总被引:2,自引:0,他引:2  
将著名的Dini定理拓展为拓扑空间到线性拓扑空间或度量空间的连续映射,并给出推广后定理的几种证法及一些推论。  相似文献   

6.
单值映射空间的各种拓扑结构是众所周知的,Smithson(1971,1973)首先将点态收敛拓扑,紧致开拓扑和一致收敛拓扩推广到集值映射空间中去。之后,Pushpa,Jain和Shashi Prabha Arga(1975)等人又将图象拓扑,σ-拓扑,Near-拓扑推广到集值映射空间。本文研究集值映射空间紧致开拓扑结构,及有关 的主要结果。  相似文献   

7.
设FTOP是模糊化拓扑空间及模糊化不定映射的范畴,L-FTOP是L-fuzzy拓扑空间及连续映射的范畴,Set是集合及映射的范畴,证明了FTOP和L-FTOP都是Set上的拓扑范畴.  相似文献   

8.
在不分明化拓扑空间中,给出了人们广为关注的拓扑学中的θ闭包的概念,并由此军政府了θ-开集,θ-闭集,θ-连续映射和强θ-连续映射,使用逻辑的语议的方法讨论了他们的有关性质,在不分明化拓扑中导入了θ-拓扑空间,描述了强θ-映射的四种等价刻划和θ-连续映射的四个必要条件。  相似文献   

9.
给出 L - fuzzifying连续映射的若干等价刻画 ,运用集合套的方法 ,证明了 :一映射为L - fuzzifying连续映射的充要条件是它在每个截集拓扑空间中是连续的  相似文献   

10.
给出L-fuzzifying连续映射的若干等价刻画,运用集合套的方法,证明了:一映射为L-fuzzifying连续映射的充要条件是它在每个截集拓扑空间中是连续的。  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.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

15.
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   

16.
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   

17.
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   

18.
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   

19.
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   

20.
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   

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