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1.
令《Xn,n≥1》为i.i.d.非负r.v.s.,Xn,1≤Xn,2≤…≮Xn,n为Xi,i≤n的次序统计量。《sn,n≥1》为一正常数列,记Nn=max《k≤n:Xn,1+Xn,1+…+Xn,k≤sn》。本文讨论了Nn的几乎处处收敛性与渐近正态性,改进了Bruss的结果。  相似文献   

2.
设有线性回归模型:yi=α+βxi+εi,只能观察到(zi,δi),其中zi=min(yi,ti),δi=I(yi≤ti),i=1,2,…,n.本文讨论了{ti}独立不必同分布条件下,β的估计以及它的相合性和渐近正态性  相似文献   

3.
记《Xn,n≥1》为独立冈分布的随机变量列。以Xn,1≤…≤Xn,n记X1,…,Xn的次序系统计量。作者将陆续给出3篇文章来讨论和Sn(ln,rn)=^r^n^-^1∑i=n+1Xn,i+pnXn,ln+qnXn,rn当n→∞时的渐近分布。这些文章所使用的方法是统一且初等的。作为上述和的特例,本文将改进文献中关于截断和及修断和及修正截断和的某些结果,还将讨论一类新的截断和──边项次序统计量的和。本  相似文献   

4.
设n=2^λ-1+t,λ〉2,0≤t〈2^λ-1。反馈函数xn=f(x0,x1,…,xn-1)=1+x0+Σi∈It(xi+xn-i)产生n阶de Bruijn-Good图Gn的一个完全因子PFλ(2^λ-1+t)其中It={t;(ti)是奇整数,1≤i≤t}。  相似文献   

5.
X′=(x1,x2…,xn),问在∑ni=1x2i≤1条件下,a3=∑n-2i=1xixi+2,a5=∑n-1i=1xixi+1,当X取遍∑ni=1x2i≤1上的点,(a3,a5)在平面上构成怎样的图形?该文对n=4给出解析解  相似文献   

6.
B值一致渐近鞅的局部收敛性及大数定律   总被引:3,自引:1,他引:3  
设(Ω,F,P)是概率空间,B是p阶一致光滑空间,X=(Xn,Fn,n≥1)是B值一致渐近鞅,则有:(1){∑∞n=1E(‖dXn‖βM‖dXn‖β-1+Mβ/Fn-1)<∞,1≤β≤p,M>0,supn≥1‖Xn‖<∞}{Xn收敛}(2){∑∞n=1E(‖dXn‖β(Mn)‖dXn‖β-1+(Mn)β/Fn-1)<∞,M>0,1≤β≤p}{Xnn收敛于0}(3)若对任意的x≥0及n≥1,均有P(‖dXn‖≥x)≤aP(Y≥x),其中Y是一正实值随机变量,EY<∞,E(Yln+Y)<∞,a是一正实数,那么Xnna.s.收敛于0.上述结论推广与改进了若干熟知的重要结果  相似文献   

7.
设(X,Y)表示一个绝对连续的二维总体,从中抽取容量的n的样本,用Xi:n表示,X样本的第i个顺序统计量,同Xi,n相对应的Y样本值用Y(i:n)表示,Y(i:n)被称为第i个顺序统计量的伴随,对1≤k≤n,设Vk,n=max(Y(n-k+1:n)^...,Y(n:n)给出了(Vk,n,Y(n:n)有限样本的联合分布,并且在线性模型下,研究了它的渐近分布,进而可以得到Y(n:n)/Vk,n这一统计  相似文献   

8.
X'=(x1,x2,…,xn),问在Σi=1↑nxi^2≤1条件下,a3=Σi=1↑n-2xixi+2,a5=Σi=1↑n=1xixi+1,当X取遍Σi=1↑nxi^2≤上的点,(a3,a5)在平面上构成怎样的图形?该文对n=4给出解析解。  相似文献   

9.
非扩张映射序列迭代过程的收敛性   总被引:1,自引:0,他引:1  
设D为赋范空间X的子集,Tn:D→X,对所有x,y∈D和所有的i,j≥1,有‖Tx-Tjy‖≤‖x-y‖成立,给定D中的一个序列(xn)与两个实数序列(tn)和(sn)满足(i)0≤tn≤t〈1且∞∑n=1tn=∞,(ii)0≤sn≤1且∞∑n=1Sn〈∞,(iii)Xn+1=tnTn(snTnxn+(1-sn)xn)+(1-tn)xn,n=1,2,3,...证明了如果(xn)有界,则linn→∞  相似文献   

10.
谭智平 《衡阳师专学报》1996,14(6):21-24,49
对只有一个变点模型x(i/n)=f(i/n)+α(i/n),其中,f(ft)=「J1+S1(t-t0),0〈t≤t0,J2+S2(t-t0),t0〈t≤1,ε(n/n),…,ε(n/n)独立同分布,J1,J2,S1,S2,t0为未知参数,讨论了变点t0处,跳变度(J2-J1)和坡变度(S2-S1)的联合分布。  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.
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   

13.
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   

14.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  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.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

18.
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   

19.
20.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

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