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1.
至多一个变点的Γ分布的统计推断   总被引:1,自引:2,他引:1  
对至多一个变点的Γ分布,即X1,…,Xn为一列相互独立的随机变量序列,且X1,…,Xk0 i.i.d~Γ(x;ν1,λ1),Xk0+1,…,Xn i.i.d~Γ(x;ν2,λ2),其中k0未知,称k0为该序列的变点.借助Gauss过程理论和滑窗方法,利用第一型极值分布逼近本文提出的统计量的分布,给出了检测变点k0的程序和变点的区间估计.最后对文中提出的统计量进行模拟并分析.  相似文献   

2.
研究了一类Witt型李代数自同构群和其相关的交换结合代数的自同构群 ,得到如下结果 :设F为一个特征为0的域 ,t1 ,t=- 2 ,… ,tn 为F上几个交换的变元 ,F(t1 ,t2 ,…tn)表示t1 ,t2 ,… ,tn 生成的分式域 ,令D = ni=1 F ti,则得到一类witt单李代数且有Aut(F(t1 ,t2 ,… ,tn)D) Aut(F(t1 ,t2 ,… ,tn) ) .  相似文献   

3.
考虑时滞微分方程组 X(t)=F[t;X(t),X(t-τ_λ(t)),…,X(t-τ_m(t))] (1)其中X∈R~n,F:J×R~n…×R~n—→R~n;J=[t_0-Δ,∞);R~n表示n维欧氏空间,0≤τ_j(t)≤Δ,Δ为常数,_j∈I_m={1,2,…,m}。总设τ_j(t),_j∈I_m在t≥t_0上连续的;F[t;0,…,0]≡0,且设F足够光滑以保证方程,(1)的解存在唯一。  相似文献   

4.
在文[1]中,作者拓广了文[2—4]中的结果,得到下述定理: 定理1、设(X,ρ)是完备度量空间,算子F:X→X满足以下条件: (1)ρ(Fx,Fy)<ρ(x,y),x,y∈X(x≠y) (2)存在N{f;f(t)≥0,t∈[0,∞]}中的点列{f_n(t)},使ρ(F~nx,F~ny)≤f_n[ρ(x,y),x,y∈X (3)sum from n=1 to ∞ f_n(t)<∞,t≥0 则算子F在X中存在唯一的不动点。本文指出定理1中的压缩条件(1)可用F连续的条件,即成立以下结果: 定理2:设(X,ρ)是完备度量空间,算子F:X→X连续,且满足定理1中的条件  相似文献   

5.
其中(x~1,x~2,…,x~n)是点p∈G的局部坐标,(X~1,X~2,…,X~n)是属于C~r类(1≤r≤s)的逆变向量.用f(p,t)表示在t=0时经过点p的方程组(1)的轨道. 定义.设F是G关于(1)之闭的不变子集合,称F为渐近稳定,若  相似文献   

6.
Γ分布参数变点的非参数统计推断   总被引:2,自引:0,他引:2  
对至多一个变点的Γ分布,即X1,…,Xn为一列相互独立的随机变量序列,且X1,…,X[nτ0]i.i.d-Γ(x;ν1,λ1),X[nτ0]+1,…,Xni.i.d-Γ(x;2ν,λ2),其中τ0未知,称τ0为该序列的变点.利用累积和方法给出了检测变点τ0位置的程序,并给出了变点τ0估计^τ的强相合性和强收敛速度.  相似文献   

7.
1 PreliminariesLet(Ω ,F ,P)beaprobabilityspace .Let{Xn ,t,n ,t≥1} denoteanarrayofrandomvariableson (Ω ,F ,P) .Let{Fn,t,-∞ 0 ,‖X‖qisdefinedas(E|X|q) 1q ,whereXisanLqintegrablerandomvariable .AnLqintegrablearray{Xn,t,Fn ,t}iscalledanLq mixin galearrayifthereexistnonnegativeconstants{Cn ,t,n ,t≥ 1}and { ψ(m) ,m≥ 0 } suchthatψ(m) ↓ 0asm→∞andforallt≥ 1andm ≥ 0 wehave‖ (X…  相似文献   

8.
至多一个变点的Г分布的统计推断   总被引:4,自引:0,他引:4  
对至多一个变点的Г分布,即X1,…,Xn为一列相互独立的随机变量序列,且X1,…,Xk0 i.i.d~Г(x;ν,λ1),Xk0 1,…,Xn i.i.d~Г(x;ν2,λ2),其中k0未知,称k0为该序列的变点.借助Gauss过程理论和滑窗方法,利用第一型极值分布逼近本提出的统计量的分布,给出了检测变点k0的程序和变点的区间估计.最后对中提出的统计量进行模拟并分析.  相似文献   

9.
余慧敏 《广西科学》2007,14(4):365-366
给定来自一未知连续分布函数F的容量为n的子样x1,x2,…,xn,考虑分布函数F的不变估计问题.在非对称损失函数L(F(t),d(t))=b∫(exp{a[d(t)-F(t)]}-a[d(t)-F(t)]-1)dF(t)和单调变换群下得到F的最优不变估计为d(t,X)=∑ni=0ciI(x(i)≤t≤x(i 1)),其中ci=1/aln(∫01ti(1-t)n-idt)/(∫01exp{-at}ti(1-t)n-idt),a≠0,b>0.  相似文献   

10.
11.
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   

12.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

13.
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   

14.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

15.
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   

16.
17.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

18.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

19.
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   

20.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

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