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Calculate Joint Probability Distribution of Steady Directed Cyclic Graph with Local Data and Domain Casual Knowledge 被引量:1
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作者 Qin Zhang Kun Qiu Zhan Zhang 《China Communications》 SCIE CSCD 2018年第7期146-155,共10页
It is desired to obtain the joint probability distribution(JPD) over a set of random variables with local data, so as to avoid the hard work to collect statistical data in the scale of all variables. A lot of work has... It is desired to obtain the joint probability distribution(JPD) over a set of random variables with local data, so as to avoid the hard work to collect statistical data in the scale of all variables. A lot of work has been done when all variables are in a known directed acyclic graph(DAG). However, steady directed cyclic graphs(DCGs) may be involved when we simply combine modules containing local data together, where a module is composed of a child variable and its parent variables. So far, the physical and statistical meaning of steady DCGs remain unclear and unsolved. This paper illustrates the physical and statistical meaning of steady DCGs, and presents a method to calculate the JPD with local data, given that all variables are in a known single-valued Dynamic Uncertain Causality Graph(S-DUCG), and thus defines a new Bayesian Network with steady DCGs. The so-called single-valued means that only the causes of the true state of a variable are specified, while the false state is the complement of the true state. 展开更多
关键词 directed cyclic graph probabilistic reasoning parameter learning causality complex network
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On the Signless Laplacian Spectral Radius of C4-free k-cyclic Graphs
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作者 KONG Qi WANG Li-gong 《Chinese Quarterly Journal of Mathematics》 2017年第3期238-245,共8页
A k-cyclic graph is a connected graph of order n and size n + k-1. In this paper, we determine the maximal signless Laplacian spectral radius and the corresponding extremal graph among all C_4-free k-cyclic graphs of ... A k-cyclic graph is a connected graph of order n and size n + k-1. In this paper, we determine the maximal signless Laplacian spectral radius and the corresponding extremal graph among all C_4-free k-cyclic graphs of order n. Furthermore, we determine the first three unicycles and bicyclic, C_4-free graphs whose spectral radius of the signless Laplacian is maximal. Similar results are obtained for the(combinatorial) 展开更多
关键词 k-cyclic graph C4-free signless Laplacian spectral radius Laplacian spectral radius
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Algebraic Properties of Edge Ideals of Some Vertex-Weighted Oriented Cyclic Graphs 被引量:1
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作者 Hong Wang Guangjun Zhu +2 位作者 Li Xu Jiaqi Zhang Zhongming Tang 《Algebra Colloquium》 SCIE CSCD 2021年第2期253-268,共16页
We provide some exact formulas for the projective dimension and regularity of edge ideals associated to some vertex-weighted oriented cyclic graphs with a common vertex or edge.These formulas axe functions in the weig... We provide some exact formulas for the projective dimension and regularity of edge ideals associated to some vertex-weighted oriented cyclic graphs with a common vertex or edge.These formulas axe functions in the weight of the vertices,and the numbers of edges and cycles.Some examples show that these formulas are related to direction selection and the assumption that w(x)≥2 for any vertex x cannot be dropped. 展开更多
关键词 projective dimension REGULARITY edge ideal cyclic graph with a common vertex cyclic graph with a common edge
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Completely Positive Matrices Having Cyclic Graphs
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作者 张晓东 李炯生 《Journal of Mathematical Research and Exposition》 CSCD 2000年第1期27-31,共5页
We prove that a CP matrix A having cyclic graph has exactly two minimal rank 1 factorization if det M(A) > 0 and has exactly one minimal rank 1 factorization if detM(A) = 0.
关键词 completely positive matrix cyclic graph minimal rank 1 factorization.
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CYCLIC BANDWIDTH SUM OF GRAPHS 被引量:2
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作者 Hao JianxiuDept.ofMath.,ZhengzhouUniv.,Zhengzhou450052,Dept.ofMath.,AnyangTeachersCollege,Anyang45500 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2001年第2期115-121,共7页
Let G be a simple graph. The cyclic bandwidth sum problem is to determine a labeling of graph G in a cycle such that the total length of edges is as small as possible. In this paper, some upper and lower bound... Let G be a simple graph. The cyclic bandwidth sum problem is to determine a labeling of graph G in a cycle such that the total length of edges is as small as possible. In this paper, some upper and lower bounds on cyclic bandwidth sum of graphs are studied. 展开更多
关键词 graph labeling cyclic bandwidth sum optimal cyclic labeling.
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Cyclically Interval Total Colorings of Cycles and Middle Graphs of Cycles 被引量:1
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作者 Yongqiang Zhao Shijun Su 《Open Journal of Discrete Mathematics》 2017年第4期200-217,共18页
A total coloring of a graph G is a functionsuch that no adjacent vertices, edges, and no incident vertices and edges obtain the same color. A k-interval is a set of k consecutive integers. A cyclically interval total ... A total coloring of a graph G is a functionsuch that no adjacent vertices, edges, and no incident vertices and edges obtain the same color. A k-interval is a set of k consecutive integers. A cyclically interval total t-coloring of a graph G is a total coloring a of G with colors 1,2,...,t, such that at least one vertex or edge of G is colored by i,i=1,2,...,t, and for any, the set is a -interval, or is a -interval, where dG(x) is the degree of the vertex x in G. In this paper, we study the cyclically interval total colorings of cycles and middle graphs of cycles. 展开更多
关键词 TOTAL COLORING INTERVAL TOTAL COLORING cyclically INTERVAL TOTAL COLORING CYCLE MIDDLE graph
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Locally Transitive Graphs Admitting a Group with Cyclic Sylow Subgroups
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作者 CHEN SHANG-DI FENG QING-LIN Du Xian-kun 《Communications in Mathematical Research》 CSCD 2010年第3期239-254,共16页
All graphs are finite simple undirected and of no isolated vertices in this paper. Using the theory of coset graphs and permutation groups, it is completed that a classification of locally transitive graphs admitting ... All graphs are finite simple undirected and of no isolated vertices in this paper. Using the theory of coset graphs and permutation groups, it is completed that a classification of locally transitive graphs admitting a non-Abelian group with cyclic Sylow subgroups. They are either the union of the family of arc-transitive graphs, or the union of the family of bipartite edge-transitive graphs. 展开更多
关键词 graph locally-transitive-graph Sylow subgroup cyclic group
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Cyclic Reconfigurable Flow Shop under Different Configurations Modeling and Optimization Based on Timed Event Graph
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作者 REN Si-Cheng XU De WANG Fang TAN Min 《自动化学报》 EI CSCD 北大核心 2006年第1期15-20,共6页
Based on the idea that modules are independent of machines, different combinations of modules and machines result in different configurations and the system performances differ under different configurations, a kind o... Based on the idea that modules are independent of machines, different combinations of modules and machines result in different configurations and the system performances differ under different configurations, a kind of cyclic reconfigurable flow shops are proposed for the new manufacturing paradigm-reconfigurable manufacturing system. The cyclic reconfigurable flow shop is modeled as a timed event graph. The optimal configuration is defined as the one under which the cyclic reconfigurable flow shop functions with the minimum cycle time and the minimum number of pallets. The optimal configuration, the minimum cycle time and the minimum number of pallets can be obtained in two steps. 展开更多
关键词 循环流程 制造业 时间事件 建模 优化设计
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General Cyclic Orthogonal Double Covers of Finite Regular Circulant Graphs
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作者 Ramadan El-Shanawany Hanan Shabana 《Open Journal of Discrete Mathematics》 2014年第2期19-27,共9页
An orthogonal double cover (ODC) of a graph H is a collection of subgraphs (pages) of H, so that they cover every edge of H twice and the intersection of any two of them contains exactly one edge. An ODC G of H is cyc... An orthogonal double cover (ODC) of a graph H is a collection of subgraphs (pages) of H, so that they cover every edge of H twice and the intersection of any two of them contains exactly one edge. An ODC G of H is cyclic (CODC) if the cyclic group of order is a subgroup of the automorphism group of G. In this paper, we introduce a general orthogonal labelling for CODC of circulant graphs and construct CODC by certain classes of graphs such as complete bipartite graph, the union of the co-cycles graph with a star, the center vertex of which, belongs to the co-cycles graph and graphs that are connected by a one vertex. 展开更多
关键词 graph Decomposition cyclic ORTHOGONAL DOUBLE Cover AUTOMORPHISM Group ORTHOGONAL Labelling
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Super Cyclically Edge Connected Half Vertex Transitive Graphs
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作者 Haining Jiang Jixiang Meng Yingzhi Tian 《Applied Mathematics》 2013年第2期348-351,共4页
Tian and Meng in [Y. Tian and J. Meng, λc -Optimally half vertex transitive graphs with regularity k, Information Processing Letters 109 (2009) 683 - 686] shown that a connected half vertex transitive graph with regu... Tian and Meng in [Y. Tian and J. Meng, λc -Optimally half vertex transitive graphs with regularity k, Information Processing Letters 109 (2009) 683 - 686] shown that a connected half vertex transitive graph with regularity k and girth g(G) ≥ 6 is cyclically optimal. In this paper, we show that a connected half vertex transitive graph G is super cyclically edge-connected if minimum degree δ(G) ≥ 6 and girth g(G) ≥ 6. 展开更多
关键词 cyclic EDGE-CONNECTIVITY cyclically Optimal Super cyclically Edge-Connected HALF VERTEX TRANSITIVE graph
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融合局部-全局历史模式与历史知识频率的时序知识图谱补全方法
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作者 贾凯 王阳萍 +1 位作者 杨景玉 张希权 《计算机应用研究》 北大核心 2025年第6期1727-1733,共7页
时序知识图谱(temporal knowledge graphs,TKGs)是动态描述事实演变的图谱,其补全任务是根据历史预测未来未知的事实,关键在于洞察历史数据。然而,现有模型在捕捉历史事件的特征方面存在局限,不能准确地从时间戳中提取有用信息。从历史... 时序知识图谱(temporal knowledge graphs,TKGs)是动态描述事实演变的图谱,其补全任务是根据历史预测未来未知的事实,关键在于洞察历史数据。然而,现有模型在捕捉历史事件的特征方面存在局限,不能准确地从时间戳中提取有用信息。从历史演进的视角出发,综合考虑历史事实的顺序、频率和周期性模式有利于预测未来事实。为此,提出了融合局部-全局历史模式与历史知识频率的时序知识图谱补全算法(LGH-HKF)。具体来说,首先使用一个局部循环图编码器网络来建模相邻时间戳上事件的内在关联与动态演变;其次使用全局历史编码器网络考虑所有以前时间戳上的相关事实,以避免丢失在相邻时间戳上没有出现的实体或关系;然后通过历史知识频率学习模块学习这些事实的频率分数来丰富模型的预测依据;最后在两个编码器之间进行权衡后,由一个具有周期性的解码器进行推理补全。使用了四个基准数据集来评估所提方法,实验结果证明LGH-HKF在大多数情况下相比于目前其他模型有很强的竞争力。 展开更多
关键词 时序知识图谱 补全算法 局部循环图编码器 全局历史编码器 历史知识频率
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两个循环群半直积上Cayley图中的处处非零3-流
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作者 王雪 李良辰 《洛阳师范学院学报》 2025年第8期1-3,共3页
Tutte猜想提出任意一个4边连通图都存在一个处处非零3-流.验证了这个猜想对于定义在两个循环群的半直积上的Cayley图是成立的.
关键词 处处非零3-流 CAYLEY图 循环群 半直积
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On the Girth of Tanner (5,7) Quasi-Cyclic LDPC Codes
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作者 Hengzhou Xu Baoming Bai +1 位作者 Dan Feng Cheng Sun 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2017年第6期80-89,共10页
The girth plays an important role in the design of LDPC codes. In order to determine the girth of Tanner(5,7) quasi-cyclic( QC) LDPC codes with length 7p for p being a prime with the form 35 m + 1,the cycles of length... The girth plays an important role in the design of LDPC codes. In order to determine the girth of Tanner(5,7) quasi-cyclic( QC) LDPC codes with length 7p for p being a prime with the form 35 m + 1,the cycles of lengths 4,6,8,and 10 are analyzed. Then these cycles are classified into sixteen categories,each of which can be expressed as an ordered block sequence,or a certain type. It is also shown that the existence of these cycles is equal to polynomial equations over Fpwho has a 35th unit root. We check if these polynomial equations have a 35th unit root and obtain the girth values of Tanner(5,7) QC LDPC codes. 展开更多
关键词 LDPC CODES quasi-cyclic Tanner graph GIRTH
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On the Spectra of Strong Power Graphs of Finite Groups
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作者 Ruiqin FU Xuanlong MA 《Journal of Mathematical Research with Applications》 CSCD 2019年第5期453-458,共6页
Let G be a finite group of order n. The strong power graph of G is the undirected graph whose vertex set is G and two distinct vertices x and y are adjacent if x^n1 = y^n2 for some positive integers n1,n2 < n. In t... Let G be a finite group of order n. The strong power graph of G is the undirected graph whose vertex set is G and two distinct vertices x and y are adjacent if x^n1 = y^n2 for some positive integers n1,n2 < n. In this paper, we give the characteristic polynomials of the distance and adjacency matrix of the strong power graph of G, and compute its distance and adjacency spectrum. 展开更多
关键词 strong POWER graph cyclic group characteristic POLYNOMIAL spectrum
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求Ramsey数下界的循环巧妙图搜索算法研究 被引量:11
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作者 宋恩民 董向锋 许如初 《应用数学》 CSCD 北大核心 1995年第4期424-428,共5页
本文研究通过构造循环巧妙图而搜寻Ramsey数下界的算法。给出了一个效率较高的算法,该算法已经编程实现,并由此得出了一个具有46点(4,7)循环巧妙图,从而证明了了r(4,7)≥47。
关键词 RAMSEY数 循环巧妙图 下界 搜索算法 图论
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经典Ramsey数R(5,12),R(5,13),R(5,14)和R(5,15)的新下界 被引量:11
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作者 苏文龙 罗海鹏 吴康 《广西大学学报(自然科学版)》 CAS CSCD 1997年第4期298-299,共2页
构造4个素数阶循环图,得到了4个Ramsey数的新下界:R(5,12)≥150,R(5,13)≥158,R(5,14)≥182,R(5,15)≥198.
关键词 RAMSEY数 下界 循环图
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9个经典Ramsey数R(3,t)的新下界 被引量:4
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作者 陈红 吴康 +2 位作者 许晓东 苏文龙 梁文忠 《数学杂志》 CSCD 北大核心 2011年第3期582-586,共5页
本文研究了经典Ramsey数R(3,t)的下界问题.利用素数阶循环图的性质改进一般阶循环图团数的计算方法,获得了9个经典Ramsey数R(3,t)的新下界:R(3,29)≥183,R(3,30)≥189,R(3,32)≥213,R(3,33)≥218,R(3,34)≥226,R(3,35)≥231,R(3,36)≥23... 本文研究了经典Ramsey数R(3,t)的下界问题.利用素数阶循环图的性质改进一般阶循环图团数的计算方法,获得了9个经典Ramsey数R(3,t)的新下界:R(3,29)≥183,R(3,30)≥189,R(3,32)≥213,R(3,33)≥218,R(3,34)≥226,R(3,35)≥231,R(3,36)≥239,R(3,37)≥244,R(3,38)≥256,其中前三个结果分别改进了迄今已知的最好的下界,后6个结果是本文首次报道的. 展开更多
关键词 RAMSEY数 下界 循环图
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基于图论的路网交通检测器之布点 被引量:12
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作者 林培群 徐建闽 《控制理论与应用》 EI CAS CSCD 北大核心 2010年第12期1605-1611,共7页
为获取各路段的交通流量,将路网检测器布点问题转变成寻求有向图的流控制子图的问题.首先将任意路网抽象为有向图,定义弧的度表征路段的重要性,证明完全有向回路图(CCG)的若干结论后给出CCG最小流控制子图的获取算法,同时给出有向图非... 为获取各路段的交通流量,将路网检测器布点问题转变成寻求有向图的流控制子图的问题.首先将任意路网抽象为有向图,定义弧的度表征路段的重要性,证明完全有向回路图(CCG)的若干结论后给出CCG最小流控制子图的获取算法,同时给出有向图非回路部分的流控制子图获取方法,进而提出能在任意路网上进行检测器优化布点的完整算法.算例选取广州火车东站附近的路网,结果验证了所提出的方法的有效性. 展开更多
关键词 检测器布点 路网 交通流量 图论 流控制子图 完全有向回路图
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基于攻击图的网络安全概率计算方法 被引量:45
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作者 叶云 徐锡山 +1 位作者 贾焰 齐治昌 《计算机学报》 EI CSCD 北大核心 2010年第10期1987-1996,共10页
针对基于攻击图的概率计算中循环路径导致的攻击图难以理解和概率重复计算问题以及渗透之间的相关性导致的概率错误计算问题,通过将攻击图与通用安全脆弱点评估系统结合,删除攻击图中的不可达路径,简化了攻击图,提出了适用于大规模网络... 针对基于攻击图的概率计算中循环路径导致的攻击图难以理解和概率重复计算问题以及渗透之间的相关性导致的概率错误计算问题,通过将攻击图与通用安全脆弱点评估系统结合,删除攻击图中的不可达路径,简化了攻击图,提出了适用于大规模网络的最大可达概率的概念和计算方法,解决了概率重复计算问题,有效避免了相关性导致的概率错误计算问题,并通过真实实验和模拟实验验证了所提方法的合理性和有效性.与相关的研究成果相比,最大可达概率计算方法可以适应于更复杂的攻击图,具有很好的扩展性. 展开更多
关键词 攻击图 循环路径 相关性 累计成功概率 最大可达概率
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步长为1和(2n+1)/3的2n阶循环图的导出匹配可扩性 被引量:5
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作者 徐华锋 王晓凤 《河南大学学报(自然科学版)》 CAS 北大核心 2006年第3期12-14,共3页
根据原晋江在《导出匹配可扩图》一文中给出的图的导出匹配可扩性的概念,采用把图的任意匹配扩充为完美匹配的方法,研究了步长为1和(2n+1)/3的2n阶循环图的导出匹配可扩性,得出主要结论为:当n≥4时,步长为1和(2n+1)/3的2n阶循环图是导... 根据原晋江在《导出匹配可扩图》一文中给出的图的导出匹配可扩性的概念,采用把图的任意匹配扩充为完美匹配的方法,研究了步长为1和(2n+1)/3的2n阶循环图的导出匹配可扩性,得出主要结论为:当n≥4时,步长为1和(2n+1)/3的2n阶循环图是导出匹配可扩的. 展开更多
关键词 导出匹配 完美匹配 可扩的 循环图
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