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1.
本文研究完备度量空间X中满足ρ(Xnrxw+1)≤LP(xn+1,Xn)+sn的点列{xn}收敛性问题,其中L∈(0,1)为常数,εn非负是无穷小量称为扰动,文中的主要结论是:点列{Xn}的收敛性由扰动εn决定,即当幂级数岛∑n=1^∞ εnxn的收敛半径R〉I/L时,点列{xn}收敛,特别地,当R〉1时,点列收敛;而时,{xn}敛散性不能确定。  相似文献   

2.
研究了双随机Dirichlet级数f(s,ω)=∑^∞n=1anXne^-λn^s在{Xn}独立不同分布并满足lim/n→∞E|Xn|>0,supn≥1E|Xn|^p<∞,(p>1)等条件时的收敛性和增长性,得到了比较好的结果。  相似文献   

3.
运用简化原理,得到了对称随机级数∑n=1^∞Xn(ω)fn(x)若在Lω^2中a.s.收敛或Cesaro有界,则它关于dω^-(x)几乎必然几乎处处收敛的结果,并给出一反例,说明这个结果的逆是不正确的.然后研究了在一般的情况下,当随机系数{Xn}满足“A↓n〉0,EXn=0,aE1/2|Xn|^2≤E|Xn|〈∞”的条件下,该级数收敛的充分必要条件.  相似文献   

4.
利用矿混合序列推广的Borel—Cantelli引理及一些收敛定理,在条件EXn=0,偏d〉0,Э0〈α^2σ^2n=α^2E|Xn|^2≤E^2|Xn|〈∞下,研究系数为矿混合序列的随机Dirichiet级数∑n=0^∞Xn(ω)e^-λn^5互的增长性,得出其增长级和非随机Dirichlet级数的增长级有类似的性质。  相似文献   

5.
二重随机Dirichlet级数所表示的整函数线性增长性   总被引:1,自引:0,他引:1  
研究了二重随机变量列{Xmn}在某阶矩一致有界条件下的性质,结合二重Dirichlet级数的增长性成果,得出结论:在适当条件下,二重随机Dirichlet级数∑m=1^∞∑n=1^∞amnXmn e^-λm^s-μn^t a.s。与二重Dirichletxe ovt ∑m=1^∞∑n=1^∞amn e^-λm^s-μn^t有相同的线性增长级。  相似文献   

6.
设M是一个紧致n维C^∞黎曼流形,f∈Diff(M),∧是f的闭不变集合,并且∧具有连续不变分解T∧M=E F,则对任意的ε〉o和λ∈(0,1),存在δ〉0,使得对f的任意λ-拟双曲强δ-伪轨{xi,ni}i=-∞^+∞都存在一点x∈M,强ε-跟踪{xi,ni}i=-∞^+∞。  相似文献   

7.
设K是Banach空间E中非空闭凸集.{Ti}i-1^N是K中具公共不动点集F=∩i-1^NF(Ti)的Lipschitz映像族,其中F(Ti)=(x∈KiTix=x},{αn}n-1^∞},{βn}n-1^∞包含[0,1]是实数列,且∑n=1∞(1-αn)〈+∞,(1-αn)L^2〈1,这里L是{Ti}i=1^N的公共Lipschitz系数.对任意x0∈K,{xn}n-1^∞由文中隐格式组(2)和(3)产生,则(i){xn}在K中收敛;(ii){xn}收敛于{Ti)i=1^N公共不动点的充分必要条件是lim d(xn,F)=0.对于(2),如聚βn=0。隐格式组变为xn=αnxn-1+(1-αn)Tm^2xn,如果βn=1,隐格式组变为Xu与Or1的形式xn=αnxn-1+(1-αn)Tnxn,对于(3),如果βn=1,隐格式组变为显格式xn=αnxn-1+(1-αn)Tnxn-1.对于这三种特殊迭代格式,结论(i)(ii)自然成立.  相似文献   

8.
广义复合泊松风险模型的大偏差与破产时刻   总被引:1,自引:1,他引:0  
进一步研究广义复合泊松风险模型的大偏差问题,其中{N(t);t≥0}是一强度为λ〉0的泊松分布,{Xn;n≥1}是独立同分布的随机变量序列,具有共同分布F,(其中0〈μ=EX1〈∞.){M(t);t≥0}是一强δ〉0的泊松分布,{N(t);t≥0},{Xn;n≥1}和{M(t);t≥0}是相互独立的.理赔剩余过程S(t)∑i=1^N(t)Xi-cM(t),t≥0.在F∈C上得到了一系列大偏差和破产时刻的结果,这些结果可以应用在某些金融与保险问题中.  相似文献   

9.
二重B-值随机Dirichlet级数收敛性   总被引:1,自引:0,他引:1  
研究二重B-值随机变量列{Xmm}在某阶矩一致有界条件下的性质,结合有关二重Dirichlet级数的成果,证明在一定条件下,二重B-值随机Dirichlet级数∑ ∞m=1∑ ∞n=1amnXmne-λms-μnta.s.几乎必然与二重Dirichlet级数∑ ∞m=1∑ ∞n=1amne-λms-μnt有相同的成对的相关收敛横坐标.  相似文献   

10.
对给定的一转移函数族,通过构造两种不同的双链{(Xn,T^nε0 ^∞),n≥0}和{(Xn,εn),n≥0},用两种不同的方法分别证明了单无限随机环境中一般状态空间马氏链的存在性。  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   

20.
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   

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