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51.
研究了铜的二维电解沉淀物在限制条件下的分形维数.拍摄了铜沉淀物随时间变化的照片,使用盒维法分析了各种条件下的豪斯多夫分形维数,并建立了计算机评估模型,以证明电压对豪斯多夫维数的重要影响.根据照片显示沉淀物的欧几里德几何形状也有着规则的变化.  相似文献   
52.
研究复Fuzzy数列科技的收敛性,讨论复Fuzzy数列度量收敛与水平收敛的等价性问题。为复Fuzzy分析的进一上研究打下良好的基础。  相似文献   
53.

In this note, we show, in a quantitative fashion, that the limit set of a non-elementary Kleinian group is uniformly perfect if the quotient orbifold is of Lehner type, i.e., if the space of integrable holomorphic quadratic differentials on it is continuously contained in the space of (hyperbolically) bounded ones. This result covers the known case when the group is analytically finite. As applications, we present estimates of the Hausdorff dimension of the limit set and the translation lengths in the region of discontinuity for such a Kleinian group. Several examples will also be given.

  相似文献   

54.
Convergence of the Magnus Series   总被引:1,自引:0,他引:1  
The Magnus series is an infinite series which arises in the study of linear ordinary differential equations. If the series converges, then the matrix exponential of the sum equals the fundamental solution of the differential equation. The question considered in this paper is: When does the series converge? The main result establishes a sufficient condition for convergence, which improves on several earlier results.  相似文献   
55.
Anstract Using a method which has been recently introduced by Besson, Courtois and Gallot we give new simple proofs of Ahlfors’ measure theorem and of Canary’s estimate of the Hausdorff-dimension of the limit set of a Kleinian group in terms of the volume of the convex-core.   相似文献   
56.
Self-Affine Sets and Graph-Directed Systems   总被引:1,自引:0,他引:1  
He  Lau  Rao 《Constructive Approximation》2008,19(3):373-397
   Abstract. A self-affine set in R n is a compact set T with A(T)= ∪ d∈ D (T+d) where A is an expanding n× n matrix with integer entries and D ={d 1 , d 2 ,···, d N } ⊂ Z n is an N -digit set. For the case N = | det(A)| the set T has been studied in great detail in the context of self-affine tiles. Our main interest in this paper is to consider the case N > | det(A)| , but the theorems and proofs apply to all the N . The self-affine sets arise naturally in fractal geometry and, moreover, they are the support of the scaling functions in wavelet theory. The main difficulty in studying such sets is that the pieces T+d, d∈ D, overlap and it is harder to trace the iteration. For this we construct a new graph-directed system to determine whether such a set T will have a nonvoid interior, and to use the system to calculate the dimension of T or its boundary (if T o ≠  ). By using this setup we also show that the Lebesgue measure of such T is a rational number, in contrast to the case where, for a self-affine tile, it is an integer.  相似文献   
57.
Based on a scheme by Lau and Ngai, a sufficient and necessary condition for an IFS of contractive similitudes to satisfy the open set condition is given. A class of Sierpinski carpets with parameters (λ1,λ2) is then investigated.  相似文献   
58.
Wolfe Duality for Interval-Valued Optimization   总被引:1,自引:0,他引:1  
Weak and strong duality theorems in interval-valued optimization problem based on the formulation of the Wolfe primal and dual problems are derived. The solution concepts of the primal and dual problems are based on the concept of nondominated solution employed in vector optimization problems. The concepts of no duality gap in the weak and strong sense are also introduced, and strong duality theorems in the weak and strong sense are then derived.  相似文献   
59.
Let B^H={B^H(t),t∈R^N+}be a real-valued(N,d)fractional Brownian sheet with Hurst index H=(H1,…,HN).The characteristics of the polar functions for B^H are discussed.The relationship between the class of continuous functions satisfying Lipschitz condition and the class of polar-functions of B^H is obtained.The Hausdorff dimension about the fixed points and the inequality about the Kolmogorov’s entropy index for B^H are presented.Furthermore,it is proved that any two independent fractional Brownian sheets are nonintersecting in some conditions.A problem proposed by LeGall about the existence of no-polar continuous functions satisfying the Holder condition is also solved.  相似文献   
60.
概率空间上一类集合的分形维数   总被引:1,自引:1,他引:0  
设{X  相似文献   
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