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991.
For a system of ordinary differential equations of the form
,
, we obtain new upper bounds for the second norm of Green's matrix using the integral performance criterion for dichotomy and bounds of the Hausdorff set of the matrix A. These estimates are considerably better for many applications than some well-known ones. 相似文献
992.
The real trees form a class of metric spaces that extends the class of trees with edge lengths by allowing behavior such as
infinite total edge length and vertices with infinite branching degree. Aldous's Brownian continuum random tree, the random
tree-like object naturally associated with a standard Brownian excursion, may be thought of as a random compact real tree.
The continuum random tree is a scaling limit as N→∞ of both a critical Galton-Watson tree conditioned to have total population size N as well as a uniform random rooted combinatorial tree with N vertices. The Aldous–Broder algorithm is a Markov chain on the space of rooted combinatorial trees with N vertices that has the uniform tree as its stationary distribution. We construct and study a Markov process on the space of
all rooted compact real trees that has the continuum random tree as its stationary distribution and arises as the scaling
limit as N→∞ of the Aldous–Broder chain. A key technical ingredient in this work is the use of a pointed Gromov–Hausdorff distance to
metrize the space of rooted compact real trees.
Berkeley Statistics Technical Report No. 654 (February 2004), revised October 2004. To appear in Probability Theory and Related Fields.
SNE supported in part by NSF grants DMS-0071468 and DMS-0405778, and a Miller Institute for Basic Research in Science research
professorship
JP supported in part by NSF grants DMS-0071448 and DMS-0405779
AW supported by a DFG Forchungsstipendium 相似文献
993.
994.
研究了N指标d维广义Wiener过程像集的一致维数和测度,得到了其像集的致Hausdorff维数和一致Packing维数。 相似文献
995.
Howard Weiss 《Journal of statistical physics》1992,69(3-4):879-886
We derive several variational formulas for the topological entropy and SRB entropy of Axiom A flows on compact manifolds and for the Hausdorff dimension of basic sets for Axiom A diffeomorphisms on compact surfaces. 相似文献
996.
A. V. Pokrovskii 《Mathematical Notes》2005,77(3-4):539-545
Suppose that P(x, D) is a linear differential operator of order m > 0 with smooth coefficients whose derivatives up to order m are continuous functions in the domain G n (n 1), 1 < p > , s > 0, and q=p/(p – 1). In this paper, we show that if n, m, p, and s satisfy the two-sided bound 0 n – q(m – s)< n, then for a weak solution of the equation P(x, D)u=0 from the Sharpley-DeVore class C
p
s
(G)loc, any closed set in G is removable if its Hausdorff measure of order n – q(m – s) is finite. This result strengthens the well-known result of Harvey and Polking on removable singularities of weak solutions to the equation P(x, D)u=0 from the Sobolev classes and extends it to the case of noninteger orders of smoothness.Translated from Matematicheskie Zametki, vol. 77, no. 4, 2005, pp. 584–591.Original Russian Text Copyright © 2005 by A. V. Pokrovskii.This revised version was published online in April 2005 with a corrected issue number. 相似文献
997.
RuanHuojun SuWeiyi 《分析论及其应用》2004,20(2):158-166
In this paper, we firstly define a decreasing sequence {P^n(S)} by the generation of the Sierpinski gasket where each P^n(S) can be obtained in finite steps. Then we prove that the Hausdorff measure H^8(S) of the Sierpinski gasket S can be approximated by {P^n(S)} with P^n(S)/(1 1/2^n-3)s ≤ H^8(S)≤ Pb(S).An algorithm is presented to get P^n(S) for n≤ 5. As an application, we obtain the best lower bound of H^8(S) till now: H^8(S) ≥ 0.5631. 相似文献
998.
We study several extensions of Besov spaces; these extensions include the oscillation spaces Ops,swhich take into account
correlations between the positions of large wavelet coefficients through the scales and, more generally,
spaces defined through the distributions of suprema of wavelet coefficients on wavelet subtrees. These
spaces are independent of the particular wavelet basis chosen. Examples of applications will be taken
from image processing and multifractal analysis. 相似文献
999.
The multifractal spectrum of some moran measures 总被引:3,自引:0,他引:3
WU Min School of Mathematical Sciences South China University of Technology Guangzhou China 《中国科学A辑(英文版)》2005,48(8):1097-1112
The multifractal formalism is shown to hold for a class of Moran measures supported on the Moran fractals associated with the sequences of which the frequency of the letter exists. 相似文献
1000.
We study the Hausdorff dimensions of invariant sets for self-similarand self-affine iterated function systems in the Heisenberggroup. In our principal result we obtain almost sure formulaefor the dimensions of self-affine invariant sets, extendingto the Heisenberg setting some results of Falconer and Solomyakin Euclidean space. As an application, we complete the proofof the comparison theorem for Euclidean and Heisenberg Hausdorffdimension initiated by Balogh, Rickly and Serra-Cassano. 2000Mathematics Subject Classification 22E30, 28A78 (primary), 26A18,28A78 (secondary). 相似文献