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流形元覆盖系统自动形成方法之研究 被引量:24
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作者 曹文贵 速宝玉 《岩土工程学报》 EI CAS CSCD 北大核心 2001年第2期187-190,共4页
系统地探讨了流形元覆盖系统的形成方法 ,基于三角形有限元网格 ,探讨了流形元数学覆盖和物理覆盖及其流形元分析网格的形成技术 ,研究了流形元两套覆盖编号的自动形成方法。
关键词 流形元方法 数学覆盖 物理覆盖 覆盖编号
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与一般相似度函数相关的谱聚类的收敛性 被引量:17
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作者 高炜 周定轩 《中国科学:数学》 CSCD 北大核心 2012年第10期985-994,共10页
谱聚类算法由与相似度函数相关的图Laplace算子的特征函数产生.本文证明与一般相似度函数相关的谱聚类算法的收敛性,并使用覆盖数方法对收敛性给出量化估计.当相似度函数是欧氏空间子集上一个Lipschitzs>0函数时,O((log(n+1))~(1/2... 谱聚类算法由与相似度函数相关的图Laplace算子的特征函数产生.本文证明与一般相似度函数相关的谱聚类算法的收敛性,并使用覆盖数方法对收敛性给出量化估计.当相似度函数是欧氏空间子集上一个Lipschitzs>0函数时,O((log(n+1))~(1/2)/n~(1/2))形式的收敛率得到证实.我们同时指出一个相应函数集的覆盖数的增长可以表现任意差. 展开更多
关键词 谱聚类 图Laplace算子 相似度函数 收敛率 覆盖数
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C^s相似度函数下正则谱聚类的收敛阶(英) 被引量:14
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作者 高炜 张云港 梁立 《兰州大学学报(自然科学版)》 CAS CSCD 北大核心 2011年第2期109-111,共3页
用覆盖数逼近的方法给出Cs相似度函数下正则谱聚类的收敛阶.
关键词 正则谱聚类 相似度函数 覆盖数 图像分割 本体相似度计算
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EDGE COVERING COLORING AND FRACTIONAL EDGE COVERING COLORING 被引量:10
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作者 MIAOLianying LIUGuizhen 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2002年第2期187-193,共7页
Abstract. Let G be a graph with edge set E(G). S E(G) is called an edge cover of G ifevery vertex of G is an end vertex of some edges in S. The edge covering chromatic numberof a graph G, denoted by Xc(G) is the maxim... Abstract. Let G be a graph with edge set E(G). S E(G) is called an edge cover of G ifevery vertex of G is an end vertex of some edges in S. The edge covering chromatic numberof a graph G, denoted by Xc(G) is the maximum size of a partition of E(G) into edgecovers of G. It is known that for any graph G with minimum degree δ,δ- 1 The fractional edge covering chromatic number of a graph G, denoted by Xcf(G), is thefractional matching number of the edge covering hypergraph H of G whose vertices arethe edges of G and whose hyperedges the edge covers of G. In this paper, we studythe relation between X’c(G) and δ for any graph G, and give a new simple proof of theinequalities δ - 1 ≤ X’c(G) ≤ δ by the technique of graph coloring. For any graph G, wegive an exact formula of X’cf(G), that is,where A(G)=minand the minimum is taken over all noempty subsets S of V(G) and C[S] is the set of edgesthat have at least one end in S. 展开更多
关键词 Edge covering coloring fractional edge covering chromatic number hyper-graph.
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Binding Number and Fractional k-Factors of Graphs
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作者 Renying Chang 《Journal of Applied Mathematics and Physics》 2024年第7期2594-2600,共7页
In this paper, we consider the relationship between the binding number and the existence of fractional k-factors of graphs. The binding number of G is defined by Woodall as bind(G)=min{ | NG(X) || X |:∅≠X⊆V(G) }. It ... In this paper, we consider the relationship between the binding number and the existence of fractional k-factors of graphs. The binding number of G is defined by Woodall as bind(G)=min{ | NG(X) || X |:∅≠X⊆V(G) }. It is proved that a graph G has a fractional 1-factor if bind(G)≥1and has a fractional k-factor if bind(G)≥k−1k. Furthermore, it is showed that both results are best possible in some sense. 展开更多
关键词 Binding number Fractional k-Factor Fractional Matching Independent Set covering Set
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加权再生核空间中信号的随机采样稳定性
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作者 张雅静 蒋英春 《桂林电子科技大学学报》 2024年第1期52-57,共6页
针对一般概率分布获取的独立随机样本,在核函数不满足对称性的条件下,在加权再生核子空间中研究了信号的随机采样稳定性。首先,基于加权再生核子空间的框架刻画,在有界区域上用有限维子空间逼近加权再生核空间。其次,通过研究加权再生... 针对一般概率分布获取的独立随机样本,在核函数不满足对称性的条件下,在加权再生核子空间中研究了信号的随机采样稳定性。首先,基于加权再生核子空间的框架刻画,在有界区域上用有限维子空间逼近加权再生核空间。其次,通过研究加权再生核子空间中信号的无穷范数与p范数的关系,估计标准化有限维子空间的覆盖数。最后,证明了当采样量足够大时,能量集中于立方体上的加权再生核信号的随机采样稳定性以高概率成立。 展开更多
关键词 加权再生核空间 覆盖数 概率密度函数 随机采样 采样稳定性
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Learning rates of least-square regularized regression with polynomial kernels 被引量:3
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作者 LI BingZheng WANG GuoMao 《Science China Mathematics》 SCIE 2009年第4期687-700,共14页
This paper presents learning rates for the least-square regularized regression algorithms with polynomial kernels. The target is the error analysis for the regression problem in learning theory. A regularization schem... This paper presents learning rates for the least-square regularized regression algorithms with polynomial kernels. The target is the error analysis for the regression problem in learning theory. A regularization scheme is given, which yields sharp learning rates. The rates depend on the dimension of polynomial space and polynomial reproducing kernel Hilbert space measured by covering numbers. Meanwhile, we also establish the direct approximation theorem by Bernstein-Durrmeyer operators in $ L_{\rho _X }^2 $ with Borel probability measure. 展开更多
关键词 learning theory reproducing kernel Hilbert space polynomial kernel regularization error Bernstein-Durrmeyer operators covering number regularization scheme 68T05 62J02
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On the Relations of Graph Parameters and Its Total Parameters
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作者 Jing-wen Li Zhi-wen Wang +3 位作者 Jaeun Lee Moo Young Sohn Zhong-fu Zhang En-qiang Zhu 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2010年第3期525-528,共4页
In this paper we get some relations between α(G), α'(G), β(G), β'(G) and αT(G), βT(G). And all bounds in these relations are best possible, where α(G), α'(G),/3(G), β(G), αT(G) and ... In this paper we get some relations between α(G), α'(G), β(G), β'(G) and αT(G), βT(G). And all bounds in these relations are best possible, where α(G), α'(G),/3(G), β(G), αT(G) and βT(G) are the covering number, edge-covering number, independent number, edge-independent number (or matching number), total covering number and total independent number, respectively. 展开更多
关键词 GRAPH covering number edge covering number independent number edge independent number total covering number total independent number
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On the Covering Number c_λ(3,W_4^((3)),v) 被引量:1
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作者 Yan WU Yan-xun CHANG 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2012年第4期631-638,共8页
Abstract A t-hyperwhesl (t 〉 3) of length l (or Wz(t) for brevity) is a t-uniform hypergraph (V, E), where t E= {e1,e2,...,el} and vl,v2,...,vt are distinct vertices of V = Ui=1 ei such that for i= 1,...,1, ... Abstract A t-hyperwhesl (t 〉 3) of length l (or Wz(t) for brevity) is a t-uniform hypergraph (V, E), where t E= {e1,e2,...,el} and vl,v2,...,vt are distinct vertices of V = Ui=1 ei such that for i= 1,...,1, vi,vi+1 ∈ei and ei ∩ ej = P, j ∈ {i - 1, i,i + 1}, where the operation on the subscripts is modulo 1 and P is a vertex of V which is different from vi, 1 〈 i 〈 l. In this paper, the minimum covering problem of MCλ(3, W(3),v) is investigated. Direct and recursive constructions on MCλ(3, W(3),v) are presented. The covering number cλ(3, W4(3), v) is finally determined for any positive integers v 〉 5 and A. 展开更多
关键词 t-(v Г λ) covering EXCESS covering number candelabra (F t)-system
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反射波法地震勘探在工程勘察中的应用 被引量:4
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作者 何强 黎大虎 +1 位作者 赖敏 何玉林 《地震研究》 CSCD 北大核心 2001年第3期258-261,共4页
对于地下复杂的地质构造 ,地震反射波法比折射波法能够提供更多更详细的地下信息。多次覆盖反射波法观测系统可以增加同一反射点的重复观测次数 ,从而起到压制干扰、提高有效波信号的作用。其次选取合适的地震参数能有效地拓宽有效波频... 对于地下复杂的地质构造 ,地震反射波法比折射波法能够提供更多更详细的地下信息。多次覆盖反射波法观测系统可以增加同一反射点的重复观测次数 ,从而起到压制干扰、提高有效波信号的作用。其次选取合适的地震参数能有效地拓宽有效波频带范围 。 展开更多
关键词 覆盖次数 反射波法 分辨率 地震勘探 工程勘探 地质构造
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RELATIONS AMONG SOME PARAMETERS OF HYPERGRAPHS
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作者 Sun Haina Bu Yuehua 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2006年第4期487-492,共6页
The relations among the dominating number, independence number and covering number of hypergraphs are investigated. Main results are as follows:Dv(H)≤min{α≤(H), p(H), p(H), T(H)}; De(H)≤min{v(H), T... The relations among the dominating number, independence number and covering number of hypergraphs are investigated. Main results are as follows:Dv(H)≤min{α≤(H), p(H), p(H), T(H)}; De(H)≤min{v(H), T(H), p(H)}; DT(H) ≤αT(H); S(H)≤ Dv (H) + α(H)≤n; 2≤ Dv (H) + T(H) ≤n; 2 〈 Dv (H) + v(H)≤n/2 + [n/r]; Dv (H) + p(H) 〈_n;2≤De(H) + Dv(H)≤n/2 + [n/r];α(H) + De(H)≤n;2 ≤ De(H) + v(H)≤2[n/r]; 2 De(H) + p(H)≤n-r + 2. 展开更多
关键词 HYPERGRAPHS dominating number independence number covering number
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Functionals on the Spaces of Convex Bodies 被引量:2
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作者 Chuanming ZONG 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2016年第1期124-136,共13页
In geometry, there are several challenging problems studying numbers associated to convex bodies. For example, the packing density problem, the kissing number problem, the covering density problem, the packing-coverin... In geometry, there are several challenging problems studying numbers associated to convex bodies. For example, the packing density problem, the kissing number problem, the covering density problem, the packing-covering constant problem, Hadwiger's covering conjecture and Borsuk's partition conjecture. They are flmdamental and fascinating problems about the same objects. However, up to now, both the methodology and the technique applied to them are essentially different. Therefore, a common foundation for them has been much expected. By treating problems of these types as functionals defined on the spaces of n-dimensional convex bodies, this paper tries to create such a foundation. In particular, supderivatives for these functionals will be studied. 展开更多
关键词 Packing density covering density kissing number Hadwiger's conjecture
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完全3-一致超图的一类填充问题和覆盖问题 被引量:2
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作者 冯弢 柴钊 常彦勋 《中国科学:数学》 CSCD 北大核心 2012年第6期619-633,共15页
设Γ是一些单t-一致超图的集合.填充设计Pλ(t,Γ,v)(或覆盖设计Cλ(t,Γ,v))是一个二元有序组(X,B),其中X是完全t-一致超图λKv(t)的顶点集,B是λKv(t)的一些子超图的集合,要求每个子超图都同构于Γ中的某一个超图,每个子超图称为是一... 设Γ是一些单t-一致超图的集合.填充设计Pλ(t,Γ,v)(或覆盖设计Cλ(t,Γ,v))是一个二元有序组(X,B),其中X是完全t-一致超图λKv(t)的顶点集,B是λKv(t)的一些子超图的集合,要求每个子超图都同构于Γ中的某一个超图,每个子超图称为是一个区组,并且满足λKv(t)中的每一条边至多(或至少)含在B的λ个区组中.给定参数t,v,λ,Γ,填充设计Pλ(t,Γ,v)的最大可能的区组数称为填充数,记为dλ(t,Γ,v);覆盖设计Cλ(t,Γ,v)的最小可能的区组数称为覆盖数,记为cλ(t,Γ,v).本文将确定Γ中仅含超图K4(3)+e时的dλ(t,Γ,v)和cλ(t,Γ,v)的精确值. 展开更多
关键词 t-(v Γ λ)填充 t-(v Γ λ)覆盖 填充数 覆盖数 可分组(Γ t)-设计 t)-烛台系
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关于θ图的若干参数 被引量:3
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作者 韩金仓 张忠辅 《太原机械学院学报》 1993年第4期288-291,共4页
设s,t,l至多有一个为1的正整数,长分别为s,t,l的不同三条路的端点重合后的图称为θ图.本文研究了θ图的覆盖数,独立数,色数,边色数和全色数.
关键词 Θ函数 覆盖(数学) 独立数 色数
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Error Analysis of ERM Algorithm with Unbounded and Non-Identical Sampling 被引量:1
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作者 Weilin Nie Cheng Wang 《Journal of Applied Mathematics and Physics》 2016年第1期156-168,共13页
A standard assumption in the literature of learning theory is the samples which are drawn independently from an identical distribution with a uniform bounded output. This excludes the common case with Gaussian distrib... A standard assumption in the literature of learning theory is the samples which are drawn independently from an identical distribution with a uniform bounded output. This excludes the common case with Gaussian distribution. In this paper we extend these assumptions to a general case. To be precise, samples are drawn from a sequence of unbounded and non-identical probability distributions. By drift error analysis and Bennett inequality for the unbounded random variables, we derive a satisfactory learning rate for the ERM algorithm. 展开更多
关键词 Learning Theory ERM Non-Identical Unbounded Sampling covering number
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APPLICATIONS OF BERNSTEIN-DURRMEYER OPERATORS IN ESTIMATING THE COVERING NUMBER 被引量:1
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作者 Chunping Zhang Jianli Wang Baohuai Sheng 《Analysis in Theory and Applications》 2010年第2期186-200,共15页
The paper deals with estimates of the covering number for some Mercer kernel Hilbert space with Bernstein-Durrmeyer operators. We first give estimates of l2- norm of Mercer kernel matrices reproducing by the kernelsK... The paper deals with estimates of the covering number for some Mercer kernel Hilbert space with Bernstein-Durrmeyer operators. We first give estimates of l2- norm of Mercer kernel matrices reproducing by the kernelsK(α,β)(x,y):=∑∞k=0 Ck(α,β)(x)Qk(α,β)(y),where Qk(α,β) (x) are the Jacobi polynomials of order k on (0, 1 ), Ck(α,β) 〉 0 are real numbers, and from which give the lower and upper bounds of the covering number for some particular reproducing kernel Hilbert space reproduced by Kα,β (x, y). 展开更多
关键词 Mercer kernel matrix covering number Bernstein-Durrmeyer operator
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Reasoning and predicting POMDP planning complexity via covering numbers 被引量:1
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作者 Zongzhang ZHANG Qiming FU +1 位作者 Xiaofang ZHANG Quan LIU 《Frontiers of Computer Science》 SCIE EI CSCD 2016年第4期726-740,共15页
Partially observable Markov decision processes (POMDPs) provide a rich mathematical framework for planning tasks in partially observable stochastic environments. The notion of the covering number, a metric of captur... Partially observable Markov decision processes (POMDPs) provide a rich mathematical framework for planning tasks in partially observable stochastic environments. The notion of the covering number, a metric of capturing the search space size of a POMDP planning problem, has been proposed as a complexity measure of approximate POMDP planning. Existing theoretical results are based on POMDPs with finite and discrete state spaces and measured in the l1- metric space. When considering heuristics, they are assumed to be always admissible. This paper extends the theoretical results on the covering numbers of different search spaces, including the newly defined space reachable under inadmissible heuristics, to the ln-metric spaces. We provide a simple but scalable algorithm for estimating covering numbers. Experimentally, we provide estimated covering numbers of the search spaces reachable by following different policies on several benchmark problems, and analyze their abilities to predict the runtime of POMDP planning algorithms. 展开更多
关键词 POMDP planning complexity theory covering number search space
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匹配数与控制数相等的图的结构性质 被引量:1
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作者 单而芳 康丽英 《数学进展》 CSCD 北大核心 2004年第2期229-235,共7页
我们分别用γ(G),β(G)和0α(G)表示图G的控制数、匹配数和覆盖数,对任意连通图,有γ(G)≤β(G)≤α(G)成立,1998年,Randerath和Volkmann给出了控制数等于覆盖数的图的特征,本文首先证明了匹配数与控制数相等的图其最小度不超过2,而后... 我们分别用γ(G),β(G)和0α(G)表示图G的控制数、匹配数和覆盖数,对任意连通图,有γ(G)≤β(G)≤α(G)成立,1998年,Randerath和Volkmann给出了控制数等于覆盖数的图的特征,本文首先证明了匹配数与控制数相等的图其最小度不超过2,而后给出了最小度为2的图的结构性质。 展开更多
关键词 匹配数 控制数 图论 覆盖数 悬挂点 孤立点
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图支配数的若干问题
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作者 林可容 张忠辅 《福州大学学报(自然科学版)》 CAS CSCD 1990年第4期1-5,共5页
本文研究了图的支配数和图的独立数、覆盖数间的关系,得到了一系列不可改进的结果。
关键词 支配数 独立数 覆盖数
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Generalization errors of Laplacian regularized least squares regression 被引量:2
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作者 CAO Ying CHEN DiRong 《Science China Mathematics》 SCIE 2012年第9期1859-1868,共10页
Semi-supervised learning is an emerging computational paradigm for machine learning,that aims to make better use of large amounts of inexpensive unlabeled data to improve the learning performance.While various methods... Semi-supervised learning is an emerging computational paradigm for machine learning,that aims to make better use of large amounts of inexpensive unlabeled data to improve the learning performance.While various methods have been proposed based on different intuitions,the crucial issue of generalization performance is still poorly understood.In this paper,we investigate the convergence property of the Laplacian regularized least squares regression,a semi-supervised learning algorithm based on manifold regularization.Moreover,the improvement of error bounds in terms of the number of labeled and unlabeled data is presented for the first time as far as we know.The convergence rate depends on the approximation property and the capacity of the reproducing kernel Hilbert space measured by covering numbers.Some new techniques are exploited for the analysis since an extra regularizer is introduced. 展开更多
关键词 semi-supervised learning graph Laplemian covering number learning rate
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