随机次自相似集的表示

本文引进了随机次自相似集与随机推移集的概念,讨论了随机次自相似集的结构,并证明了任一随机集是随机次自相似集的充分必要条件是：该随机集可以表为某一个随机推移集的某个像集。     

自相似集的质量分布原理与Hausdorff测度及其应用

本文提出了满足开集条件的自相似集的质量分布原理.作为应用,得到了计算一类满足开集条件的自相似集的Hausdorff测度的准确值的方法,并举例说明了此方法对于计算一类满足开集条件的自相似集的Hausdorff测度的准确值是行之有效的.     

两分支的自相似集的间隙序列

本文研究了两分支的自相似集的间隙序列与维数之间的关系.Besicovitch和Taylor证明了R上的自相似集的维数由它的间隙序列所确定(见文献[1]).利用生成函数的方法,证明了对一类两分支的自相似集,其间隙序列由维数所确定;并且猜测这一结论对一般的自相似集均成立.     

控制系统中的分形

本文将整数维与分形的Hausdorff测度引入并应用于控制系统,同时也介绍了准自相似集这个新概念,证明了这种集合的存在性与唯一性.并将计算自相似集维数的公式推广到准自相似集,在此基础上,说明了控制系统的可达集可以具有分数维.表明在分析非线性系统可控性与可观性时,分形几何学也将是一种有意义的工具.     

Sierpinski地毯上自相似测度以及Markov测度的加倍性质

众所周知,当自相似集满足强分离条件时,其上的自相似测度都是加倍的.本文进一步证明在强分离条件下,自相似集上的Markov测度都是加倍的.随后,本文讨论了Sierpinski地毯S上自相似测度及Markov测度的加倍性质.当S不满足强分离条件时,将S分为不同的类型,完全刻画了S上加倍的自相似测度及加倍的Markov测度.     

多分支自相似集的自仿嵌入

本文研究了一类多分支自相似集的自仿嵌入.利用压缩映射的不动点,在一定条件下,证明了若一个自相似集能自仿嵌入到另一个自相似集中,则它们对应的迭代函数系的压缩比满足某种代数性质.     

具有强分离条件的自相似集的最大密度（英文）

本文证明对于满足强分离条件的自相似集E,存在一个闭凸集达到它的最大密度.即存在一个闭凸集V■E0(|V|0),使得sup{μ(U)/|U|s:U■E0}=μ(V)/|V|s,其中U为闭集,E0表示自相似集E的闭凸壳,μ表示E上的唯一自相似概率测度.作为应用,我们给出命题"满足强分离开集条件的自相似集具有最优几乎处处覆盖"的一个新证明.     

平面上一类自相似集的共形维数

本文证明了平面上一类自相似集的共形维数为1.此外还证明了这些自相似集与任何Hausdorff维数为1的度量空间都不是拟对称等价的.这表明,对于这些自相似集而言,共形维数定义中的下确界不能达到.     

自相似集边界的结构及维数

本文研究了一类由平面上点的表示系统所生成的内部非空的自相似集,证明其边界曲线的一半是三个A－完备集的并集,并给出计算这类完备集的结构矩阵的简单方法,从而利用Marion定理得出这类自相似集边界的Hausdorff维数。     

多分支自相似集的自仿嵌入（英文）

本文研究了一类多分支自相似集的自仿嵌入.利用压缩映射的不动点,在一定条件下,证明了若一个自相似集能自仿嵌入到另一个自相似集中,则它们对应的迭代函数系的压缩比满足某种代数性质.     

Local Regularity of L∞ ∞-Refinable Function Vectors

This article discusses the local regularity of refinable function vectors associated with a dilation matrix M. Suppose that D is a complete set of representatives of Z^s/MZ^s. Under the assumptions that the self-affine tile T (M,D), associated with dilation matrix M and digit set D, has measure 1 and that the corresponding refinable function vector φ ∈ L_∞, we prove that there is a set H ? R^s of full measure such that the restriction φ|_H of φ on H has a positive Hölder exponent α(x) at every x ∈ H. Similar result holds for the derivatives of refinable function vectors provided that the dilation matrix is diagonalizable.     

On the Connectedness of Self-Affine Tiles

Let T be a self-affine tile in Rⁿ defined by an integral expandingmatrix A and a digit set D. The paper gives a necessary andsufficient condition for the connectedness of T. The conditioncan be checked algebraically via the characteristic polynomialof A. Through the use of this, it is shown that in R², for anyintegral expanding matrix A, there exists a digit set D suchthat the corresponding tile T is connected. This answers a questionof Bandt and Gelbrich. Some partial results for the higher-dimensionalcases are also given.     

Structure of planar integral self‐affine tilings

For a self‐affine tile in $\mathbf {R}^2$ generated by an expanding matrix $A\in M_2(\mathbf {Z})$ and an integral consecutive collinear digit set ${\mathcal D}$, Leung and Lau [Trans. Amer. Math. Soc. 359 , 3337–3355 (2007).] provided a necessary and sufficient algebraic condition for it to be disklike. They also characterized the neighborhood structure of all disklike tiles in terms of the algebraic data A and ${\mathcal D}$. In this paper, we completely characterize the neighborhood structure of those non‐disklike tiles. While disklike tiles can only have either six or eight edge or vertex neighbors, non‐disklike tiles have much richer neighborhood structure. In particular, other than a finite set, a Cantor set, or a set containing a nontrivial continuum, neighbors can intersect in a union of a Cantor set and a countable set.     

Classification of Integral Expanding Matrices and Self-Affine Tiles

   Abstract. Let T be a self-affine tile that is generated by an expanding integral matrix A and a digit set D . It is known that many properties of T are invariant under the Z -similarity of the matrix A . In [LW1] Lagarias and Wang showed that if A is a 2 × 2 expanding matrix with |det(A)| = 2 , then the Z -similar class is uniquely determined by the characteristic polynomial of A . This is not true if |det(A)| > 2. In this paper we give complete classifications of the Z -similar classes for the cases |det(A)| =3, 4, 5 . We then make use of the classification for |det(A)| =3 to consider the digit set D of the tile and show that μ(T) >0 if and only if D is a standard digit set. This reinforces the conjecture in [LW3] on this.     

Spectrality of a class of self-affine measures and related digit sets

Archiv der Mathematik - This work investigates the spectrality of a self-affine measure $$\mu _{M,D}$$ and the related digit set D in the case when $$|\mathrm{det}(M)|=p^{\alpha }$$ is a prime...     

Natural Tiling, Lattice Tiling and Lebesgue Measure of Integral Self-Affine Tiles

In the existing theory of self-affine tiles, one knows thatthe Lebesgue measure of any integral self-affine tile correspondingto a standard digit set must be a positive integer and everyintegral self-affine tile admits some lattice Zⁿ as a translationtiling set of Rⁿ. In this paper, we give algorithms to evaluatethe Lebesgue measure of any such integral self-affine tile Kand to determine all of the lattice tilings of Rⁿ by K. Moreover,we also propose and determine algorithmically another type oftranslation tiling of Rⁿ by K, which we call natural tiling.We also provide an algorithm to decide whether or not Lebesguemeasure of the set K (K+j), j–Zⁿ, is strictly positive.     

Integral Self-Affine Tiles in {\Bbb R}^n Part II: Lattice Tilings

Let A be an expanding n × n integer matrix with |det (A)| = m. A standard digit set ${\cal D}Let A be an expanding n×n integer matrix with |det(A)|=m. Astandard digit set D for A is any complete set of coset representatives for? ⁿ /A(? ⁿ ). Associated to a given D is a setT (A, D), which is the attractor of an affine iterated function system, satisfyingT=∪ _d∈D (T+d). It is known thatT (A, D) tiles? ⁿ by some subset of? ⁿ . This paper proves that every standard digit set D gives a setT (A, D) that tiles? ⁿ with a lattice tiling.     

素数下的整自仿tiles的数字集

讨论了一维情形下有素数行列式值的整数自仿tiles,其数字集D的特征.通过比较b与p的关系得到如下结论：（i）pbD是mod p的一个完全剩余类;（ii）p｜bD=pγD0,其中γ∈N＊,D0是modp的一个完全剩余类.该结论可被推广到高维情形,加强了一些作者的结果.最后,给出与此结论相关的三个注记与例子.     

A small aperiodic set of Wang tiles

A new aperiodic tile set containing only 14 Wang tiles is presented. The construction is based on Mealy machines that multiply Beatty sequences of real numbers by rational constants.     

Error diffusion on simplices: The structure of bounded invariant tiles

This is a companion paper to Adleret al. (in press, 2015). There, we proved the existence of an absorbing invariant tile for the Error Diffusion dynamics on an acute simplex when the input is constant and “ergodic” and we discuss the geometry of this tile. Under the same assumptions we prove here that said invariant tile (a fundamental set of the lattice generated by the vertices of the simplex) which is a finite union of polytopes have the property that any union of the intersections of the tile with the Voronoï regions of the vertices is a tile for a different, explicitly defined lattice.