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1.
本文在充分大的k-饱和非标准模型中讨论。令(X,A,μ)是一个σ-有限的测度空间,从而存在{E_n}↑A,使X=∪E_n且μ(E_n)<+∞,n∈N。对每一A∈A及n∈N,令μ_n(A)=μ(A∩E_n)。每一个有限测度空间(X,A,μ_n)相应的Loeb空间为(~*X,~*L(~*A,~*μ_n),L(~*μ_n))。  相似文献   

2.
图K1∨Cn的非连通并图的优美性   总被引:1,自引:0,他引:1  
将k-优美图的概念进行了推广,给出了简单无向图G在集合{0,1,…,p}上的{k_n1,n2_n3,…,nt-1_nt}-标号及{k_n1,n2_n3,…,nt-1_nt}-优美图的概念,并在此定义的基础上,得出了非连通图G1∪G2是k-优美图的一个充分条件;同时证明了在一定条件下一些图是优美图的结论。  相似文献   

3.
设U_n是级数∑u_v的部分和,{λ_n}是一凸性数列,在[1],[2],[3],[4]和[5]中讨论了如下的问题:当数列{λ_n}满足怎样的条件时,级数∑λ_v u_v是|C,α|可和的?本文将进一步考虑这个问题.在本文所得的结果中,定理2,3和5是主要的.  相似文献   

4.
本文研究了在结点系{z_k~(n)=e~(((2k-1)/n)ni)}_(k=1)~n 上关于函数类 A 的 Lagrange 插补多项式的白恩斯坦—罗格辛斯基求和 U_n(f,z)=1/2{Ln(f,ze~(((s)/n)i)+Ln(f,ze~((-(s)/n)i)}在单位闭圆上的发散性与内闭一致收敛性。  相似文献   

5.
设 m≥,拓扑空间 X 称为初始 m-紧,如果每一基数不超过 m 的开覆盖都有有限子覆盖.X 称为局部初始 m-紧,如果对 X 中每一点 x,存在它的一个邻域 V,使作为 X的子空间是初始 m-紧的.本文约定 X 为正则空间,所使符号、概念见.引理1.在2~X 在中若 X∈〈U~1,…,U_m〉,其中 U_1,…U_m 为 X 中开集,则存在 X 中开集,则存在 X 中开集 V_1,…,V_n,使得 X∈〈V_1,…V_n〉〈U_1,…,U_m〉且{_1,…,_n)是 X的既约覆盖.  相似文献   

6.
k-自相似映射的结构及其应用   总被引:1,自引:0,他引:1  
研究了内积空间上k-自相似映射的结构与k-自相似映射列{An}的收敛性,并给出了相关的应用,证明了内积空间X上的映射A是一个k-自相似映射当且仅当存在X上的实线性等距U及常向量b,使得Ax=kUx+6(νx∈X);给出了X上k-自相似映射列{An}的逐点收敛性的三个等价刻画;作为应用,证明了:若{In)是欧氏空间(Rp,p)上的一列自相似压缩迭代映射系且收敛于一个自相似压缩迭代映射系I,则In的吸引子(即自相似集)S(In)依分形空间K(X)上的Hausdorff度量收敛于I的吸引子S(I).  相似文献   

7.
为了刻画k-半层空间引进k-半连续集值映射的定义,通过集值映射扩张刻画了k-半层空间和k-MCM空间. 住要证明了:对于空间X下列论断等价:(1)X是k-半层空间;(2)对每个度量空间Y,存在保序算子$\Phi$使得对每个集值映射$\varphi: X \rightarrow \mathcal {F}(Y)$都对应下半连续和k-上半连续集值映射$\Phi(\varphi): X \rightarrow \mathcal {F}(Y)$使得 $\Phi(\varphi)(x)$ 在每个点$x\in U_\varphi$有界并且$\varphi\subseteq \Phi(\varphi)$.  相似文献   

8.
设Lucas序列{U_n(P,Q)}由U_0=0,U_1=1和U_(n+1)=PU_n-QU_(n-1)给出,利用孙智宏的一个反演公式得出一些组合恒等式与U_n(P,Q)的加速递推公式.  相似文献   

9.
运用n阶矩阵B=(b_(ij))≥0的第二大特征值的结果,结合图论的背景,得出了n阶k-正则图G的第二大特征值θ_2(A(G))≤k-(?){|N_i∩N_j|},最小的特征值θ_n(A(G))满足:θ_n(A(G))≥-1-(?){k-|N_i∩N_j|-1,k- |N_i∩N_j| 1}.  相似文献   

10.
研究了微分方程~$f^{(k)}+[P_{k-1}(\mathrm{e}^{z})+Q_{k-1}(\mathrm{e}^{-z})]f^{(k-1)}+\cdots+[P_{0}(\mathrm{e}^{z})+Q_{0}(\mathrm{e}^{-z})]f=0$和 ~$f^{(k)}+[P_{k-1}(\mathrm{e}^{z})+Q_{k-1}(\mathrm{e}^{-z})]f^{(k-1)}+\cdots+[P_{0}(\mathrm{e}^{z})+Q_{0}(\mathrm{e}^{-z})]f=R_{1}(\mathrm{e}^{z})+R_{2}(\mathrm{e}^{-z})$~的解以及它们的一阶导数与小函数的关系, 其中~$P_{j}(z)$~,~$Q_{j}(z)$~$(j=0,1,2,\cdots,k-1)$~和~$R_{i}(z)(i=1,2)$~是关于~z~的多项式.  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.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

18.
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   

19.
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   

20.
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   

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