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A NEGATIVE ANSWER TO A CONJECTURE ON SELF-SIMILAR SETS WITH OPEN SET CONDITION 被引量:5
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作者 Jiandong Yin 《Analysis in Theory and Applications》 2009年第2期182-200,共19页
Zhou and Feng posed a conjecture on self-similar set in 2004. In this paper, a self-similar set is constructed which has a best covering but its natural covering is not a best one. Thus, we indeed give a negative answ... Zhou and Feng posed a conjecture on self-similar set in 2004. In this paper, a self-similar set is constructed which has a best covering but its natural covering is not a best one. Thus, we indeed give a negative answer to the conjecture. 展开更多
关键词 self-similar set best covering natural covering Hausdorff measure
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AN ANSWER TO A CONJECTURE ON SELF-SIMILAR SETS 被引量:4
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作者 Baoguo Jia Shaoyuan Xu 《Analysis in Theory and Applications》 2007年第1期9-15,共7页
In this paper, we construct a self-similar set which has a best covering but it is not the natural covering, thus negate the conjecture on self-similar sets posed by Z. Zhou in 2004.
关键词 self-similar set best covering natural covering Hausdorff measure
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THE REGULARITY OF RANDOM GRAPH DIRECTED SELF-SIMILAR SETS 被引量:2
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作者 ZhangXiaoqun LiuYanyan 《Acta Mathematica Scientia》 SCIE CSCD 2004年第3期485-492,共8页
A set in Rd is called regular if its Hausdorff dimension coincides with its upper box counting dimension. It is proved that a random graph-directed self-similar set is regular a.e..
关键词 Random graph-directed self-similar set Hausdorff dimension box-counting dimension REGULAR
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ON THE EXACT HAUSDORFF MEASURE OF A CLASS OF SELF-SIMILAR SETS SATISFYING OPEN SET CONDITION 被引量:2
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作者 Shaoyuan Xu Weiyi Su Zuoling Zhou 《Analysis in Theory and Applications》 2008年第1期93-100,共8页
In this paper, we provide a new effective method for computing the exact value of Hausdorff measures of a class of self-similar sets satisfying the open set condition (OSC). As applications, we discuss a self-simila... In this paper, we provide a new effective method for computing the exact value of Hausdorff measures of a class of self-similar sets satisfying the open set condition (OSC). As applications, we discuss a self-similar Cantor set satisfying OSC and give a simple method for computing its exact Hausdorff measure. 展开更多
关键词 self-similar set Hausdorff measure and Hausdorff dimension open set condition
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THE STRUCTURE AND APPROXIMATION OF A.S. SELF-SIMILAR SET 被引量:1
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作者 胡迪鹤 《Acta Mathematica Scientia》 SCIE CSCD 2003年第2期201-207,共7页
The structure of any a.s. self-similar set K(w) generated by a class of random elements {gn,wσ} taking values in the space of contractive operators is given and the approximation of K(w) by the fixed points {Pn,wσ} ... The structure of any a.s. self-similar set K(w) generated by a class of random elements {gn,wσ} taking values in the space of contractive operators is given and the approximation of K(w) by the fixed points {Pn,wσ} of {gn,ow} is obtained. It is useful to generate the fractal in computer. 展开更多
关键词 a.s. self-similar set Hausdorff metric fixed point STRUCTURE APPROXIMATION
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The Structure and the Sufficent and Necessary Conditions for Generalized Statistically Self-Similar Sets 被引量:1
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作者 DENG Ai-jiao HU Di-he (College of Mathematics and Computer Science,Wuhan University,Wuhan 430072,China) 《Wuhan University Journal of Natural Sciences》 CAS 2000年第1期13-21,共9页
We constructed a class of generalized statistically self-similar set.S and give the necessary and sufficent conditions to ensure a random recursive set being a generalized statistically self-similar set. The statist... We constructed a class of generalized statistically self-similar set.S and give the necessary and sufficent conditions to ensure a random recursive set being a generalized statistically self-similar set. The statistically self-similar sets defined by Hutchinson,Falconer,Graf are the special cases of ours. 展开更多
关键词 statistically recursive set generalized statistically self-similar set Hausdorff metric
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(S,T)-WEAK TRACTABILITY OF MULTIVARIATE LINEAR PROBLEMS IN THE AVERAGE CASE SETTING 被引量:1
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作者 Yongping LIU Guiqiao XU 《Acta Mathematica Scientia》 SCIE CSCD 2019年第4期1033-1052,共20页
The purpose of this article is to investigate (s, t)-weak tractability of multivariate linear problems in the average case set ting. The considered algorithms use finitely many evaluations of arbitrary linear function... The purpose of this article is to investigate (s, t)-weak tractability of multivariate linear problems in the average case set ting. The considered algorithms use finitely many evaluations of arbitrary linear functionals. Generally, we obtained matching necessary and sufficient conditions for (s,t)-weak tractability in terms of the corresponding non-increasing sequence of eigenvalues. Specifically, we discussed (s, t)-weak tractability of linear tensor product problems and obtained necessary and sufficient conditions in terms of the corresponding one-dimensional problem. As an example of applications, we discussed also (s,t)-weak tractability of a multivariate approximation problem. 展开更多
关键词 (s t)-weak TRACTABILITY LINEAR PROBLEM LINEAR tensor product PROBLEM HILBERT space AVERAGE case setting
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FRACTAL PROPERTIES OF STATISTICALLY SELF-SIMILAR SETS
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作者 余旌胡 范文涛 《Acta Mathematica Scientia》 SCIE CSCD 2000年第2期256-260,共5页
In this paper, authors compute the Packing dimension of statistically selfsimilar sets and obtaine the dimension and dimension distribution of statistically self-similar measure.
关键词 statistically self-similar set statistically self-similar measure dimension distribution contractive map
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THE EXACT MEASURES OF A CLASS OF SELF-SIMILAR SETS ON THE PLANE
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作者 Zhiwei Zhu Zuoling Zhou 《Analysis in Theory and Applications》 2008年第2期160-182,共23页
Let S belong to R^2 be the attractor of the iterated function system {f1, f2, f3 } iterating on the unit equilateral triangle So. where fi(x) =λix + bi, i = 1,2, 3, x =(x1, x2), b1=(0, 0), b3=(1-λ3 /2,√3... Let S belong to R^2 be the attractor of the iterated function system {f1, f2, f3 } iterating on the unit equilateral triangle So. where fi(x) =λix + bi, i = 1,2, 3, x =(x1, x2), b1=(0, 0), b3=(1-λ3 /2,√3/2 (1-λ3)) This paper determines the exact Hausdorff measure, centred covering measure and packing measure of S under some conditions relating to the contraction parameter. 展开更多
关键词 self-similar set Hausdorff measure centred covering measure packing measure
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A Local Property of Hausdorff Centered Measure of Self-Similar Sets
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作者 Zhiwei Zhu Zuoling Zhou 《Analysis in Theory and Applications》 2014年第2期164-172,共9页
We analyze the local behavior of the Hausdorff centered measure for self- similar sets. If E is a self-similar set satisfying the open set condition, thenC^s(E∩B(x,r))≤(2r)^sfor all x ∈ E and r〉 0, where Cs ... We analyze the local behavior of the Hausdorff centered measure for self- similar sets. If E is a self-similar set satisfying the open set condition, thenC^s(E∩B(x,r))≤(2r)^sfor all x ∈ E and r〉 0, where Cs denotes the s-dimensional Hausdorff centered measure. The above inequality is used to obtain the upper bound of the Hausdorff centered measure. As the applications of above inequality, We obtained the upper bound of the Hausdorff centered measure for some self-similar sets with Hausdorff dimension equal to 1, and prove that the upper bound reach the exact Hausdorff centered measure. 展开更多
关键词 Hausdorff centered measure Hausdorff measure self-similar sets.
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Hlder Estimate of Harmonic Functions on a Class of p.c.f. Self-Similar Sets
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作者 Donglei Tang Rui Hu Chunwei Pan 《Analysis in Theory and Applications》 2014年第3期296-305,共10页
In this paper we establish sharp H/51der estimates of harmonic functions on a class of connected post critically finite (p.c.f.) self-similar sets, and show that functions in the domain of Laplacian enjoy the same p... In this paper we establish sharp H/51der estimates of harmonic functions on a class of connected post critically finite (p.c.f.) self-similar sets, and show that functions in the domain of Laplacian enjoy the same property. Some weU-known examples, such as the Sierpinski gasket, the unit interval, the level 3 Sierpinski gasket, the hexagasket, the 3-dimensional Sierpinski gasket, and the Vicsek set are also considered. 展开更多
关键词 p.c.f self-similar sets Hoelder estimates harmonic function.
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Weakly Stable Sets of NTU Game
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作者 Han Qiao Hong-Wei Gao 《American Journal of Operations Research》 2012年第1期91-93,共3页
In this paper, the definition of weak dominance is proposed for a NTU game and two new solution concepts of NTU games are introduced: the refined core and weakly stable set. The relationship is explored among the core... In this paper, the definition of weak dominance is proposed for a NTU game and two new solution concepts of NTU games are introduced: the refined core and weakly stable set. The relationship is explored among the core, the weakly stable set and the refined core. 展开更多
关键词 NTU GAME weak DOMINANCE Core weakLY STABLE set
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Some Results on the Upper Convex Densities of the Self-Similar Sets at the Contracting-Similarity Fixed Points
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作者 Shaoyuan Xu Wangbin Xu Zuoling Zhou 《Analysis in Theory and Applications》 CSCD 2015年第1期92-100,共9页
In this paper, some results on the upper convex densities of self-similar sets at the contracting-similarity fixed points are discussed. Firstly, a characterization of the upper convex densities of self-similar sets a... In this paper, some results on the upper convex densities of self-similar sets at the contracting-similarity fixed points are discussed. Firstly, a characterization of the upper convex densities of self-similar sets at the contracting-similarity fixed points is given. Next, under the strong separation open set condition, the existence of the best shape for the upper convex densities of self-similar sets at the contracting-similarity fixed points is proven. As consequences, an open problem and a conjecture, which were posed by Zhou and Xu, are answered. 展开更多
关键词 self-similar set upper convex density Hausdorff measure and Hausdorff dimension contracting-similarity fixed point.
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The Oscillation Inequality of Harmonic Functions on Post Critically Finite Self-Similar Sets
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作者 Donglei Tang Rui Hu 《Analysis in Theory and Applications》 CSCD 2017年第2期149-156,共8页
In this paper we establish the oscillation inequality of harmonic functions and HOlder estimate of the functions in the domain of the Laplacian on connected post critically finite (p.c.f.) self-similar sets.
关键词 p.c.f. self-similar sets oscillation inequality H61der estimate harmonic functions.
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NOTE ON THE PAPER “ AN NEGATIVE ANSWER TO A CONJECTURE ON THE SELF-SIMILAR SETS SATISFYING THE OPEN SET CONDITION”
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作者 Shaoyuan Xu Wangbin Xu 《Analysis in Theory and Applications》 2012年第1期49-57,共9页
In this paper, we present a more simple and much shorter proof for the main result in the paper " An negative answer to a conjecture on the self-similar sets satisfy- ing the open set condition", which was published... In this paper, we present a more simple and much shorter proof for the main result in the paper " An negative answer to a conjecture on the self-similar sets satisfy- ing the open set condition", which was published in the journal Analysis in Theory and Applications in 2009. 展开更多
关键词 self-similar set best covering natural covering Hausdorff measure andHausdorff dimension
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Cantor Type Fixed Sets of Iterated Multifunction Systems Corresponding to Self-Similar Networks
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作者 Levente Simon Anna Soós 《Applied Mathematics》 2016年第4期365-374,共10页
We propose a new approach to the investigation of deterministic self-similar networks by using contractive iterated multifunction systems (briefly IMSs). Our paper focuses on the generalized version of two graph model... We propose a new approach to the investigation of deterministic self-similar networks by using contractive iterated multifunction systems (briefly IMSs). Our paper focuses on the generalized version of two graph models introduced by Barabási, Ravasz and Vicsek ([1] [2]). We generalize the graph models using stars and cliques: both algorithm construct graph sequences such that the next iteration is always based on n replicas of the current iteration, where n is the size of the initial graph structure, being a star or a clique. We analyze these self-similar graph sequences using IMSs in function of the size of the initial star and clique, respectively. Our research uses the Cantor set for the description of the fixed set of these IMSs, which we interpret as the limit object of the analyzed self-similar networks. 展开更多
关键词 Cantor set Fixed set Iterated Function Systems Iterated Multifunction Systems self-similar Graphs
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THE EXISTENCE THEOREM OF THE CONE-WEAK SUBDIFFERENTIAL OF SET-VALUED MAPPING 被引量:1
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作者 HUYUDA MENGZHIQING 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1998年第4期473-477,共5页
In this paper, the existence theorem of the cone weak subdifferential of set valued mapping in locally convex topological vector space is proved. Received March 30,1998. 1991 MR Subject Classification: 4... In this paper, the existence theorem of the cone weak subdifferential of set valued mapping in locally convex topological vector space is proved. Received March 30,1998. 1991 MR Subject Classification: 47H17,90C29. 展开更多
关键词 set valued mapping cone convex cone weak subgradient cone weak subdifferential.
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基于SET-CNN的紧凑型地波雷达弱目标检测方法 被引量:1
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作者 李发瑞 纪永刚 +2 位作者 任继红 程啸宇 王心玲 《海洋科学进展》 CAS CSCD 北大核心 2023年第4期753-764,共12页
紧凑型高频地波雷达发射功率较低且采用小孔径阵列,导致雷达回波中的弱目标增多,进而引起基于距离-多普勒谱的目标检测方法性能降低,目标探测能力减弱。为提高紧凑型地波雷达对弱目标的检测性能,本文提出一种基于同步提取变换-卷积神经... 紧凑型高频地波雷达发射功率较低且采用小孔径阵列,导致雷达回波中的弱目标增多,进而引起基于距离-多普勒谱的目标检测方法性能降低,目标探测能力减弱。为提高紧凑型地波雷达对弱目标的检测性能,本文提出一种基于同步提取变换-卷积神经网络(Synchroextracting Transform-Convolutional Neural Network,SET-CNN)的紧凑型地波雷达弱目标检测方法:首先在时频谱处理中,利用信噪比方法抑制信号中的海杂波,减少杂波时频脊线对目标检测的影响;然后基于SET时频谱构建时频脊线样本数据库,再通过卷积神经网络进行时频脊线分类,并基于分类结果的后处理完成船只目标检测。通过仿真和实测数据验证提出的目标检测方法,结果表明,本文提出的方法能够有效检测到弱目标,提高紧凑型地波雷达的目标检测性能。 展开更多
关键词 紧凑型高频地波雷达 同步提取变换-卷积神经网络(set-CNN) 弱目标检测 时频脊线样本数据库
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关于一些特殊图类的弱控制多项式的研究
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作者 刘慧灵 边红 +1 位作者 于海征 魏丽娜 《四川师范大学学报(自然科学版)》 CAS 2024年第1期60-66,共7页
研究一些特殊图类的弱控制多项式.令图G=(V(G),E(G))是一个简单连通图,若对任意v∈V(G),存在u∈V(G),使得uv∈E(G)且d(u)≥d(v)成立,则称v弱控制u.设W(G)?V(G),如果对任意u∈V(G)W(G),存在v∈W(G),使得v弱控制u,则称W(G)为图G的一个弱... 研究一些特殊图类的弱控制多项式.令图G=(V(G),E(G))是一个简单连通图,若对任意v∈V(G),存在u∈V(G),使得uv∈E(G)且d(u)≥d(v)成立,则称v弱控制u.设W(G)?V(G),如果对任意u∈V(G)W(G),存在v∈W(G),使得v弱控制u,则称W(G)为图G的一个弱控制集.含点数最少的弱控制集称为最小弱控制集,最小弱控制集中所包含点的个数称为图G的弱控制数,记为γwd(G).图G的弱控制多项式为WD(G,x)=nΣj=γwd(G)Wd(G,j)x印j,其中Wd(G,j)表示图G中阶为j的弱控制集的个数. 展开更多
关键词 控制集 弱控制集 弱控制数 控制多项式 弱控制多项式
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一类弱监督数据中多视角扰动的特征选择方法
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作者 郭启航 王平心 +2 位作者 杜亮 杨习贝 钱宇华 《江苏科技大学学报(自然科学版)》 CAS 2024年第2期101-108,共8页
弱标签消歧技术可以用来消除数据中的噪声标签.然而,经由弱标签消歧后的数据中依然可能存在冗余或不相关特征,因此带来了弱监督数据中的特征选择这一实际问题.在弱标签消歧后得到的数据的基础上,提出了一种基于多视角扰动的特征选择框架... 弱标签消歧技术可以用来消除数据中的噪声标签.然而,经由弱标签消歧后的数据中依然可能存在冗余或不相关特征,因此带来了弱监督数据中的特征选择这一实际问题.在弱标签消歧后得到的数据的基础上,提出了一种基于多视角扰动的特征选择框架,其能够分别从样本和特征多个视角出发,构造不同的扰动数据,以便求解出多个不同的特征选择结果,从而为后续的学习任务提供基础性集成工具.此外,所提的多视角扰动特征选择框架适用于不同类型、不同约束下的搜索进程.在12组高维数据上,通过注入5种不同比例的标签噪声和使用3种不同类型的特征度量准则,实验结果表明,所提方法求得的特征选择结果能够从准确率和稳定性的层面极大地提升分类性能. 展开更多
关键词 特征选择 多视角 粗糙集 超集学习 弱监督
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