首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到19条相似文献,搜索用时 812 毫秒
1.
讨论具有某种相对平坦性单位球结构的Banach空间的一些性质.首先根据定义证明了Banach空间c0是CL-空间,然后给出了几乎CL-空间的端点的一些性质,主要证明了几乎CL-空间的端点也是其二次对偶空间的端点.最后总结了有限维CL-空间的一些性质并得出了两个推论.  相似文献   

2.
讨论了取值于上Banach空间上的各种积分与弱 拓扑之间的关系。证明了对于具有可分共扼空间的Banach空间 ,在有界性条件下 ,映射的数量Riemann可积性与几乎处处弱连续性是等价的。引进了弱 Lebesgue性质的概念 ,证明了可分空间的共扼空间具有弱 Lebesgue性质。最后证明了 ,对于具有弱 Lebesgue性质的Banach空间 ,Riemann可积映射是Bochner可积的。  相似文献   

3.
讨论Banach空间中遗传不可分解空间与具有球覆盖性质空间的关系.证明若Banach空间X具有遗传不可分解性质,且X中的Gateaux可微点在X中稠密,则空间X具有球覆盖性质;进一步得到如果X的Gateaux可微点仅在X中的某一无穷维子空间中稠密,则X仍具有球覆盖性质.  相似文献   

4.
讨论无穷维可分Banach空间上的非游荡算子序列.根据Banach空间上非游荡算子以及Banach空间上的PDE的非游荡算子半群的定义,给出Banach空间上非游荡算子序列的定义,运用特征向量的方法证明在无穷可分解析函数Banach空间上非游荡算子序列的存在性.并给出非游荡算子序列的一些性质.  相似文献   

5.
主要讨论商Banach空间X~(**)/X,给出了X~(**)/X自反的一些性质,并证明了商自反空间具有RNP的一个充分条件,证明了经典Banach空间l_∞与c_o有相同的光滑点.  相似文献   

6.
研究Banach空间中的非扩张映象的不动点问题——在严格凸的Banach空间中证明了非扩张映象的不动点性质——非空、闭和凸性,并且讨论了特殊的严格凸空间——Hilbert空间中非扩张映象不动点的此类问题.  相似文献   

7.
证明了Σ1e型Banach空间X上黎斯算子类R(X)就等于非本性算子理想In(X),从而R(X)是B(X)中亏维为1的依算子范数闭的双侧理想;给出Σ1e型Banach空间上良有界算子的一些性质.  相似文献   

8.
通过研究Banach空间ψ-直和的k严格凸性及Banach-Saks性质,证明了若X,Y分别是k严格凸与l严格凸的Banach空间,则XψY是k+l-1严格凸的(其中ψ∈Ψ是[0,1]上的严格凸函数),并将该结果推广到有限个Banach空间的ψ-直和.另外证明了XψY具BSP当且仅当X,Y具BSP.  相似文献   

9.
讨论了K凸集的一些性质,证明了拟Banach空间是F空间,并给出了赋拟范线性空间的等价条件.  相似文献   

10.
引入K平空间、K强平的Banach空间,证明了K平的Banach空间X的共轭空间X*没有K非常光滑点,而S(X*)的非K光滑点在S(X*)中稠密,刻画了凸性更差的Banach空间的性质.另外,还引入强平模、K强平模的概念,并给出强平模、K强平模的充分必要条件.  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.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

14.
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   

15.
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   

16.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

17.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

18.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

19.
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   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号