一类随机级数的α－截集的Hausdorff维数

随机级数的截集是一类很重要的Ｆｒａｃｔａｌ集，本文确定了一类随机级数的α－截集的Ｈａｕｓｄｏｒｆｆ维数．     

分形几何从UCSMP教材内容引发的思考

分形几何从ＵＣＳＭＰ教材内容引发的思考钱玲（北京师范大学１００８７５）美国芝加哥大学数学课程设计（简称ＵＣＳＭＰ）第四册高中代数中，第１４章“维数和空间”最后一节的内容是“分形”（Ｆｒａｃｔａｌｓ），它用８页篇幅，介绍了分形的创始人曼德勃罗（Ｂｅ...     

TheQuasi-affineMapsandFractals

ＴｈｅＱｕａｓｉ－ａｆｆｉｎｅＭａｐｓａｎｄＦｒａｃｔａｌｓＬｕｎｈａｉＬＯＮＧＧａｎｇＣＨＥＮ（ＣｅｎｔｅｒｆｏｒＭａｔｈｅｍａｔｉｃａｌＳｃｉｅｎｃｅｓ，ＺｈｅｊｉａｎｇＵｎｉｖ．，Ｈａｎｇｚｈｏｕ３１００２７）Ｅ－ｍａｉｌ：ａｍａ－ｓｘｓｅｍａ...     

一类半鞅样本轨道的Fractal性质

本文用Ｈａｕｓｄｏｒｆｆ维数刻画了一类半这样本轨道的Ｆｒａｃｔａｌ性质，并由此研究了Ｂｒｏｗｎ运动与有界变差过程的碰撞问题．     

离散FitzHugh-Nagumo方程的整体吸引子和维数

该文对ＦｉｔｚＨｕｇｈ Ｎａｇｕｍｏ方程初边值问题用有限差分格式离散空间变量,证明了离散模型整体吸引子的存在性,并给出了与犿无关的Ｈａｕｓｄｏｒｆｆ维数和Ｆｒａｃｔａｌ维数上界估计。     

Dimension of the Fractal Curve in Plane and Its Derivative of the Fractional Order

Ｄｉｍｅｎｓｉｏｎ　ｏｆ　ｔｈｅ　Ｆｒａｃｔａｌ　Ｃｕｒｖｅ　ｉｎ　Ｐｌａｎｅ　ａｎｄ　Ｉｔｓ　Ｄｅｒｉｖａｔｉｖｅ　ｏｆ　ｔｈｅ　Ｆｒａｃｔｉｏｎａｌ　ＯｒｄｅｒＤｅｎｇＧｕａｎｔｉｅ（邓冠铁）（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｈｅｍａｔｉｃｓ，Ｈｕ...     

二维带形无界区域中Navier－Stokes方程整体吸引子及其维数估计

该文讨论二维无界带形区域中Ｎａｖｉｅｒ－Ｓｔｏｋｅｓ方程其中Ω＝（０，ｄ）×Ｒ，ｄ＞０为一常数，ｕ与ｐ为未知量，其中ｕ＝（ｕ１，ｕ２）为速度场，ｐ表示压力．我们证明了当ｕ０∈Ｈ，ｆ∈Ｖ且ｆ［ｌｏｇ（ｅ＋｜ｘ｜２）］１／２∈Ｌ２（Ω）时，问题（Ｉ）在Ｈ中存在整体吸引子Ａ，它是的一个子集．对Ａ的Ｈａｕｓｄｏｒｆｆ维数与Ｆｒａｃｔａｌ维数我们也给出了估计．     

二维全空间上线性阻尼Navier-Stokes方程的全局吸引子及其维数估计

本文研究二维全空间上线性阻尼Ｎａｖｉｅｒ－Ｓｔｏｋｅｓ方程的大时间性态央餐力项ｆ（ｘ）∈（Ｌ＾２（Ｒ＾２）＾２而不需要对ｆ（ｘ）作任何加权限制的条件下,证明了线性阻尼Ｎａｖｉｅｒ－Ｓｔｏｋｅｓ方程的全局吸引子的存在性,并给出了其Ｈａｕｓｄｏｒｆｆ及Ｆｒａｃｔａｌ维数估计。     

广义自相似集的重fractal分解集的点态维数及packing维数

设Ｋ为广义自相似集，μ为支撑于Ｋ上的无穷乘积测度，本文中证明了Ｋ的重ｆｒａｃｔａｌ分解集Ｋα恰好由关于测度μ的点态维数为α的点所组成，并证明了Ｋα的ｐａｃｋｉｎｇ维数与其Ｈａｕｓｄｏｒｆｆ维数一致，从而Ｋα为在Ｔａｙｌｏｒ［９］意义下的ｆｒａｃｔａｌ集。     

A Diffusion Equation on Fractals in Random Media

ＡＤｉｆｕｓｉｏｎＥｑｕａｔｉｏｎｏｎＦｒａｃｔａｌｓｉｎＲａｎｄｏｍＭｅｄｉａ１１ＴｈｅｐａｐｅｒｗａｓｒｅｃｅｉｖｅｄｏｎＪｕｌｙ．３０ｔｈ，１９９７ＤｅＬＩＵ，ＨｏｕｑｉａｎｇＬＩ，ＦｕｘｕａｎＣＨＡＮＧ＆ＨｏｎｇｍｅｉＺＨＡＮＧＤｅｐａｒｔｍ...     

Inertial fractal set and fractal structure of attractors for the ginzburg-landan equation

This paper proves that the Ginzburg-Landan partial differential equation admits an inertial fractal set whose fractal dimension is finite. Furthermore, We produce an exponentially approximating sequence of localizing compact fractal sets and a fractal structure of the attractor. This project is supported by the National Natural Science Foundation of China     

由几何反演导出的分形几何

本文介绍了由几何反演而导出的自反分形概念.构造了一个对称的,分叉自反分形曲线和一个自反分形尘集.推广了分形密切的概念而且提出了一个新的概念——分形包络.最后给出了“肥皂”和“鸡蛋”的两个自反分形的实例.     

INERTIAL FRACTAL SET AND FRACTAL STRUCTURE OF ATTRACTORS FOR THE GINZBURG-LANDAN EQUATION

1.IntroductionTheGinzburg-Landanequationsgovernthefiniteamplitudeevolutionofinstabilitywavesinalargevarietyofdissipativesystemswhichareclosetocriticallty.VariousformsoftheGinzburg-Landanequationariseinhydrodynamicinstabilitytheory:thedevelopmentofTolllnieu-SchlichtingwavesinplanePoiseuilleflows,thenonlineargrowthofconvectionrollsintheRayleigh-Benardproblem,andtheappearanceofTaylorvorticesintheflowbetweencounterrotatingcircularcylinders(see[7--9]).Theekistenceofattractorsandaninertialmanifo…     

具有有限记忆的随机分形的重分形分解

Dryakhlov和Tempelman对具有有限记忆的随机分形集的Hausdorff维数进行了研究,本文对具有有限记忆的随机分形集K(ω)的重分形分解集Kα(ω)进行研究,得到了在一定条件下,这种随机分形集重分形分解集Kα(ω)的Hausdorff维数表达式.     

具有无界变差的连续函数研究进展

讨论了具有无界变差的连续函数的结构.首先按照局部结构和分形维数对连续函数进行了分类,给出了相应的例子.对这些具有无界变差的函数的性质进行了初步的讨论.对于新定义的奇异连续函数,给出了一个等价判别定理.基于奇异连续函数,又给出了局部分形函数和分形函数的定义.同时,分形函数又由奇异分形函数、非正则分形函数和正则分形函数组成.相应于不连续函数的情形也进行了简单的讨论.     

Fractal Approximation

In the present article every complex square integrable function defined in a real bounded interval is approached by means of a complex fractal function. The approximation depends on a partition of the interval and a vectorial parameter of the iterated function system providing the fractal attractor. The original may be discontinuous or undefined in a set of zero measure. The fractal elements can modify the features of the originals, for instance their character of smooth or non-smooth. The properties of the operator mapping every function into its fractal analogue are studied in the context of the uniform and least square norms. In particular, the transformation provides a decomposition of the set of square integrable maps. An orthogonal system of fractal functions is constructed explicitly for this space. Sufficient conditions for the uniform convergence of the fractal series expansion corresponding to this basis are also deduced. The fractal approximation of real functions is obtained as a particular case.     

Some examples of singular fluid flows

We show, by an explicit construction, the existence of solutions to the Stokes system in dimension three that are singular on a fractal set. The singular points are understood in the sense given by Caffarelli, Kohn and Nirenberg [2]. As an application, we show the existence of suitable weak solutions to the Navier-Stokes equations, driven by rough forces, that are singular on a fractal set.     

Crystallization of space: Space-time fractals from fractal arithmetic

Fractals such as the Cantor set can be equipped with intrinsic arithmetic operations (addition, subtraction, multiplication, division) that map the fractal into itself. The arithmetic allows one to define calculus and algebra intrinsic to the fractal in question, and one can formulate classical and quantum physics within the fractal set. In particular, fractals in space-time can be generated by means of homogeneous spaces associated with appropriate Lie groups. The construction is illustrated by explicit examples.     

Fractal Polynomials and Maps in Approximation of Continuous Functions

The primary goal of this article is to establish some approximation properties of fractal functions. More specifically, we establish that a monotone continuous real-valued function can be uniformly approximated with a monotone fractal polynomial, which in addition agrees with the function on an arbitrarily given finite set of points. Furthermore, the simultaneous approximation and \mboxinterpolation which is norm-preserving property of fractal polynomials is established. In the final part of the article, we establish differentiability of a more general class of fractal functions. It is shown that these smooth fractal functions and their derivatives are good approximants for the original function and its \mboxderivatives.     

Zeta functions of discrete self-similar sets

In this paper we study a class of countable and discrete subsets of a Euclidean space that are “self-similar” with respect to a finite set of (affine) similarities. Any such set can be interpreted as having a fractal structure. We introduce a zeta function for these sets, and derive basic analytic properties of this “fractal” zeta function. Motivating examples that come from combinatorial geometry and arithmetic are given particular attention.