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1.
引入并讨论空间的若干种分解与合成性质,在已有的遗传不可分解和商遗传不可分解空间实例的基础上,建立起某些类Gowers-Maurey型Banach空间的新概念,证明在一般情况下,这些类新型空间上的算子构成特点简单;在相差一个严格奇异(或严格余奇异)算子理想下,是数乘算子。  相似文献   

2.
关于无限奇异算子   总被引:1,自引:1,他引:0  
讨论无限奇异算子的某些性质与其它算子类之间的关系,并用无限奇异算子来刻画遗传不可分解Banach空间,以及满足Pisier问题的空间的性质。  相似文献   

3.
主要证明了一类经典Banach空间c0,lp(1<p<∞)上存在强不可约算子,同时给出了有Schauder基的不可分解的Banach空间上强不可约算子存在性的证明.  相似文献   

4.
讨论一类不可分解的Σ1e型Banach空间上有界线性算子的谱的特殊性质;给出Σ1e型Banach空间上(B)型良有界算子的一些性质.  相似文献   

5.
本文引入 Banach 空间上无界强可分解算子概念,把有界强可分解算子的某些主要性质推广到无界强可分解算子上。最后,研究了这类算子的函数演算。  相似文献   

6.
本文讨论了Banach空间上强可分解算子的对偶性质,建立了算子T与它的对偶算子T~在强可分解性方面的对偶定理。  相似文献   

7.
自从C·Foias引进有界可分解算子概念以来,经过数学家们十几年来的努力,有界可分解算子已经得到较充分和系统的研究,形成了一部较完整的理论。最近,孙善利.王漱石分别给出了无界可分解算子的定义,研究了它们的性质,把有界可分解算子的某些主要结果推广到无界可分解算子方面。随着无界可分解算子理论的产生,象研究与有界可分解算子密切相关的其他有界算子类一样,我们有必要探讨其他无界算子类,研究它们与无界可分解算子的关系。本文引入Banach空间上有可分解谱的无界算子概念,论证了这类算子的的某些主要性质,最后证明,有可分解谱的无界算子与无界可分解算子等价,从而减弱了无界  相似文献   

8.
给出一类不可分解的Σ1e型Banach空间上有界线性算子的谱的特殊结构,证明了存在某个Σ1e型Banach空间使其上某个(B)型良有界算子T的谱σ(T)是可数无限集.  相似文献   

9.
可分解算子的Banach可约性   总被引:1,自引:0,他引:1  
Banach 空间 X 上的有界线性算子 T 称为 Banach 可约的,若存在 T 的非平凡不变子空问 M 与 N,使 X=M+N,此处+表示直接和,在本文里,我们研究了可分解算子的 Banach 可约性问题。  相似文献   

10.
本文讨论 Banach 空间上的闭可约化算子,闭谱算子及闭可分解算子的谱特征,并给出了 Banach 空间上的闭算子成为闭谱算子的充要条件。设 X 是复 Banach 空间,C(x)表示 X 中的闭线性算子全体,C_∞表示扩充复平面。定义1 T∈C(X)称为完全谱可约化算子,如果对 C_∞的每个开子集或闭子集ι及相应的谱子空间(?),存在 T 的不变子空间 M,使得  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.
<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   

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