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1.
Let X = {X(t) ∈ R~d, t ∈ R~N} be a centered space-anisotropic Gaussian random field whose components satisfy some mild conditions. By introducing a new anisotropic metric in R~d, we obtain the Hausdorff and packing dimension in the new metric for the image of X. Moreover, the Hausdorff dimension in the new metric for the image of X has a uniform version.  相似文献   

2.
Let XH = {XH(s),s ∈RN1} and X K = {XK(t),t ∈R N2} be two independent anisotropic Gaussian random fields with values in R d with indices H =(H1,...,HN1) ∈(0,1)N1,K =(K1,...,KN2) ∈(0,1) N2,respectively.Existence of intersections of the sample paths of X H and X K is studied.More generally,let E1■RN1,E2■RN2 and FRd be Borel sets.A necessary condition and a sufficient condition for P{(XH(E1)∩XK(E2))∩F≠Ф}>0 in terms of the Bessel-Riesz type capacity and Hausdorff measure of E1×E2×F in the metric space(RN1+N2+d,) are proved,where  is a metric defined in terms of H and K.These results are applicable to solutions of stochastic heat equations driven by space-time Gaussian noise and fractional Brownian sheets.  相似文献   

3.
Let X = {X(t), t ∈ ℝ N } be a Gaussian random field with values in ℝ d defined by
((1))
. The properties of space and time anisotropy of X and their connections to uniform Hausdorff dimension results are discussed. It is shown that in general the uniform Hausdorff dimension result does not hold for the image sets of a space-anisotropic Gaussian random field X. When X is an (N, d)-Gaussian random field as in (1), where X 1,...,X d are independent copies of a real valued, centered Gaussian random field X 0 which is anisotropic in the time variable. We establish uniform Hausdorff dimension results for the image sets of X. These results extend the corresponding results on one-dimensional Brownian motion, fractional Brownian motion and the Brownian sheet.   相似文献   

4.
利用非标准分析的方法,给出了S~0-类实函数的一个积分不等式和一个积分等式:(1)设A是标准的完备度量空间(X,d)中的一个准标准内的子集,μ是X上的一个Borel正则有限的标准外测度.若f是X上的一个非负的S~0-类实函数,则有°(∫_Aμ)≤∫_(°A)°fdμ.特殊情况当f≡1时,有°(μ(A))≤μ(°A);(2)设E是标准的s-紧集,若f是E上的一个S~0-类实函数,则°(∫_E fdH~s)=∫_E°fdH~s,这里°(*)指的是*的影子.并给出了这些结果在分形几何中用以判断一个分形集其内部是否非空的方法及一个分形函数在Hausdorff测度空间上的积分的计算方法,并给出了相应的实例加以验证.  相似文献   

5.
Chen  Zhen Long  Wang  Jun  Wu  Dong Sheng 《数学学报(英文版)》2021,37(12):1826-1840
Acta Mathematica Sinica, English Series - Let X = {X(t) ∈ ℝd, t ∈ ℝN} be a centered space-time anisotropic Gaussian random field whose components are independent and satisfy...  相似文献   

6.
This paper studies polar sets for anisotropic Gaussian random fields, i.e. sets which a Gaussian random field does not hit almost surely. The main assumptions are that the eigenvalues of the covariance matrix are bounded from below and that the canonical metric associated with the Gaussian random field is dominated by an anisotropic metric. We deduce an upper bound for the hitting probabilities and conclude that sets with small Hausdorff dimension are polar. Moreover, the results allow for a translation of the Gaussian random field by a random field, that is independent of the Gaussian random field and whose sample functions are of bounded Hölder norm.  相似文献   

7.
Let A be an expansive dilation on R~n and φ:R~n× [0,∞)→[0,∞) an anisotropic Musielak–Orlicz function.Let H_A~φ(R~n) be the anisotropic Hardy space of Musielak–Orlicz type defined via the grand maximal function.In this article,the authors establish its molecular characterization via the atomic characterization of H_A~φ(R~n).The molecules introduced in this article have the vanishing moments up to order s and the range of s in the isotropic case(namely,A:=2I_(n×n)) coincides with the range of well-known classical molecules and,moreover,even for the isotropic Hardy space H~p(R~n)with p∈(0,1](in this case,A:=2I_(n×n),φ(x,t) :=t~p for all x∈R~n and t∈[0,∞)),this molecular characterization is also new.As an application,the authors obtain the boundedness of anisotropic Calderón–Zygmund operators from H_A~φ(R~n) to L~φ(R~n) or from H_A~φ(R~n) to itself.  相似文献   

8.
张峰  熊炜  叶臣 《数学杂志》2000,20(2):231-236
对各向同性,算子自相似马氏过程,本文在恰当的条件下得到了其象集与图集的Hausdorff维数。其证明表明该维数的估计与其算子特征值的实部有关。  相似文献   

9.
SOME GEOMETRIC PROPERTIES OF BROWNIAN MOTION ON SIERPINSKI GASKET   总被引:1,自引:0,他引:1  
Let {X(t),t≥0} be Brownian motion on Sierpinski gasket,The Hausdorff and packing dimensions of the image of a ompact set are studied,The uniform Hausdorff and packing dimensions of the inverse image are also discussed.  相似文献   

10.
This paper is devoted to the high-dimensional and multilinear Hausdorff operators on the Heisenberg group H n. The sharp bounds for the strong type(p, p)(1 ≤ p ≤∞) estimates of n-dimensional Hausdorff operators on H n are obtained. The sharp bounds for strong(p, p) estimates are further extended to multilinear cases. As an application, we derive the sharp constant for the multilinear Hardy operator on H n. The weak type(p, p)(1 ≤ p ≤∞) estimates are also obtained.  相似文献   

11.
Haudorff测度与等径不等式   总被引:1,自引:0,他引:1  
何伟弘  罗俊  周作领 《数学学报》2005,48(5):939-946
对于:Hausdorff维数为s>0的满足开集条件的自相似集E(?)Rn(n>1),我们引入等径不等式Hs|E(X)≤|X|s,以及使该不等式等号成立而直径大于0的极限集U(?)Rn.这里,Hs|E(·)是限制到集合E上的s维Hausdorff测度,而|X|指集合X在欧氏度量下的直径.当s=n时,n维球是唯一的极限集;当s∈(1,n)时,除去一些反面例子以外,我们对上述等径不等式的极限集的基本性质所知甚少.可以看出,这些不等式与Hs(E)的准确值的计算有密切联系.作为特例,我们将考虑Sierpinski垫片,指出计算这一典型自相似集的In2/In3维Hausdorff测度准确值的困难何在.由此可以大致推想,为什么除去平凡情形以外,至今还没有一个具体的满足开集条件而维数大于1的自相似集的:Hausdorff测度准确值被计算出来.  相似文献   

12.
We determine the Hausdorff dimension of the set of double points for a symmetric operator stable Lévy process \(X=\left\{ X(t),t\in \mathbb {R}_+\right\} \) in terms of the eigenvalues of its stability exponent.  相似文献   

13.
In this paper, the Holder continuity of Westwater process X_t is concerned. More precisely,we show that there exists a random variable r_C∈(0,∞) for any C∈(3,∞) such that|X_s-X_t|≤C|(s-t)|~(1/2)|log|t-s||相似文献   

14.
钟玉泉  梅韬 《应用数学》2001,14(2):85-89
本文讨论了取值于 Rd的随机过程 Xt=( X1 ( t) ,X2 ( t) ,… ,XN( t) ) ,并且在一定条件下获得了 Xt的像集和图集的 Hausdorff维数 .这里 Xi( t) ,t∈ R 是独立的取值于 Rdi 的αi-自相似马氏过程 ,并且 ∑Ni=1 di=d.  相似文献   

15.
Let(X, G) be a dynamical system(G-system for short), that is, X is a topological space and G is an infinite topological group continuously acting on X. In the paper,the authors introduce the concepts of Hausdorff sensitivity, Hausdorff equicontinuity and topological equicontinuity for G-systems and prove that a minimal G-system(X, G) is either topologically equicontinuous or Hausdorff sensitive under the assumption that X is a T3-space and they provide a classification of transitive d...  相似文献   

16.
A model of coherent upper conditional prevision for bounded random variables is proposed in a metric space. It is defined by the Choquet integral with respect to Hausdorff outer measure if the conditioning event has positive and finite Hausdorff outer measure in its Hausdorff dimension. Otherwise, when the conditioning event has Hausdorff outer measure equal to zero or infinity in its Hausdorff dimension, it is defined by a 0–1 valued finitely, but not countably, additive probability. If the conditioning event has positive and finite Hausdorff outer measure in its Hausdorff dimension it is proven that a coherent upper conditional prevision is uniquely represented by the Choquet integral with respect to the upper conditional probability defined by Hausdorff outer measure if and only if it is monotone, comonotonically additive, submodular and continuous from below.  相似文献   

17.
A new multivariate dispersion ordering based on the Hausdorff distance between nonempty convex compact sets is proposed. This dispersion ordering depends on an index, whose purpose is to blur for each random vector the ball centered at its expected value, and with a radius equal to the index. So, on the basis of such an index, we consider a random set associated with each random vector and dispersion comparisons are established by means of the Hausdorff distance associated with the random sets. Different properties of the new dispersion ordering are stated as well as some characterization theorems. Possible relationships with other dispersion orderings are also studied. Finally, several examples are developed.  相似文献   

18.
A very important property of a deterministic self-similar set is that its Hausdorff dimension and upper box-counting dimension coincide. This paper considers the random case. We show that for a random self-similar set, its Hausdorff dimension and upper box-counting dimension are equal

  相似文献   


19.
张德学 《东北数学》2001,17(1):49-52
SupposethatXisacompactHausdorffspace,andU(X)denotesthesetofalltheuppersemicontinuousfunctionsfromXto [0 ,1 ] .ThenU(X)isacompletelatticeunderthepointwiseordering ,anditsoppositelatticeU(X) opisacontinuouslattice .ThusU(X)endowedwiththelim inftopologyonU(X) op,whic…  相似文献   

20.
The closed subspaces of finite codimension of the space C(X) of all continuous real-valued functions on a compact Hausdorff space X, for which the set of elements of best approximations of every function f C(X) is nonempty and compact, are characterized. It is shown that if the compact Hausdorff space X is infinite, then C(X) has no subspace of a finite Codimension n > 1 which has a nonempty set of elements of the best approximation for an arbitrary function f 6 (X) and which has an upper-semicontinuous metric projection.Translated from Matematicheskie Zametki, Vol. 19, No. 4, pp. 531–539, April, 1976.  相似文献   

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