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求受顶点数限制的最短路径问题的一个算法 被引量:11
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作者 孙强 杨宗源 《计算机工程》 CAS CSCD 北大核心 2002年第9期73-74,共2页
提出了求受顶点数限制的最短路径问题的一个算法,与现有的算法相比,该算法效率较高,时间复杂度为(O(k-2)n2)(k是受限制的顶点数,n是图中顶点总数);而且该算法比较简单,易于描述、实现和理解。
关键词 最短路径问题 算法 顶点数 时间复杂分析 计算机
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Nonlinear Relationship and Its Evolutionary Trace between Average Degree and Average Path Length of Edge Vertices of China Aviation Network Based on Complex Network
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作者 Cheng Xiangjun Chen Xumei Guo Jianyuan 《Journal of Traffic and Transportation Engineering》 2024年第5期224-237,共14页
In order to reveal the complex network characteristics and evolution principle of China aviation network,the relationship between the average degree and the average path length of edge vertices of China aviation netwo... In order to reveal the complex network characteristics and evolution principle of China aviation network,the relationship between the average degree and the average path length of edge vertices of China aviation network in 1988,1994,2001,2008 and 2015 was studied.According to the theory and method of complex network,the network system was constructed with the city where the airport was located as the network node and the airline as the edge of the network.On the basis of the statistical data,the average degree and average path length of edge vertices of China aviation network in 1988,1994,2001,2008 and 2015 were calculated.Through regression analysis,it was found that the average degree had a logarithmic relationship with the average path length of edge vertices and the two parameters of the logarithmic relationship had linear evolutionary trace. 展开更多
关键词 China aviation network complex network average degree of edge vertices average path length of edge vertices logarithmic relationship evolutionary trace
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两个简单多边形求交的算法 被引量:8
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作者 宋立明 闫浩文 +1 位作者 王邦松 方爱玲 《测绘与空间地理信息》 2011年第6期258-260,共3页
采用了双向链表这种数据结构,对两简单多边形的顶点及交点进行存储,在对交点进行插入时,可直接插入链表中,避免了利用单向链表或数组进行存储时对点的重复查找。通过遍历两个顶点、交点混合表,可得到两多边形的交及多边形的顶点,从而得... 采用了双向链表这种数据结构,对两简单多边形的顶点及交点进行存储,在对交点进行插入时,可直接插入链表中,避免了利用单向链表或数组进行存储时对点的重复查找。通过遍历两个顶点、交点混合表,可得到两多边形的交及多边形的顶点,从而得到两多边形的交集。相对其他类似的算法,该算法具有较快的计算速度和较高的效率。 展开更多
关键词 双向链表 多边形 顶点 交点 交集
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Lightweight design of 45000r/min spindle using full factorial design and extreme vertices design methods 被引量:7
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作者 PARK Seong-jin LEE Choon-man HWANG Young-kug 《Journal of Central South University》 SCIE EI CAS 2011年第1期153-158,共6页
Factors for determining the spindle size are the shaft diameter, positions of bearing and motor, and entire length of the spindle. Then, it is important to find the assembling of the optimal design variables, which sa... Factors for determining the spindle size are the shaft diameter, positions of bearing and motor, and entire length of the spindle. Then, it is important to find the assembling of the optimal design variables, which satisfy the stiffimss and rotational speed required to the spindle. A general full factorial design method was used to verify some factors that affect the natural frequency of a spindle. It is verified that the shorter shaft length and bearing span length represent the higher natural frequency, and there are some effects according to the change in the levels of factors. The detailed spindle dimension is determined by applying an EVD method, which can define the optimal bearing position through considering the limiting condition. Based on the estimated regression model, the optimal spindle size and bearing distance that can improve the primary natural frequency are obtained, and the influence of design factors on the natural frequency is also analyzed. 展开更多
关键词 high-speed spindle extreme vertices design natural frequency lightweight design full factorial design
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The Supersolvable Order of Hyperplanes of an Arrangement 被引量:4
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作者 Gao Rui-mei Pei Dong-he Du Xian-kun 《Communications in Mathematical Research》 CSCD 2013年第3期231-238,共8页
This paper mainly gives a sufficient and necessary condition for an order of hyperplanes of a graphic arrangement being supersolvable. In addition, we give the relations between the set of supersolvable orders of hype... This paper mainly gives a sufficient and necessary condition for an order of hyperplanes of a graphic arrangement being supersolvable. In addition, we give the relations between the set of supersolvable orders of hyperplanes and the set of quadratic orders of hyperplanes for a supersolvable arrangement. 展开更多
关键词 quadratic arrangement graphic arrangement supersolvable order of hyperplane quadratic order of hyperplane supersolvable order of vertices
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Reciprocal Distance Laplacian Eigenvalue Distribution Based on Graph Parameters
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作者 CUI Jiaxin MA Xiaoling 《新疆大学学报(自然科学版中英文)》 CAS 2024年第5期562-570,共9页
Let G be a connected graph of order n and m_(RD)^(L)_(G)I denote the number of reciprocal distance Laplacian eigenvaluesof G in an interval I.For a given interval I,we mainly present several bounds on m_(RD)^(L)_(G)I ... Let G be a connected graph of order n and m_(RD)^(L)_(G)I denote the number of reciprocal distance Laplacian eigenvaluesof G in an interval I.For a given interval I,we mainly present several bounds on m_(RD)^(L)_(G)I in terms of various structuralparameters of the graph G,including vertex-connectivity,independence number and pendant vertices. 展开更多
关键词 reciprocal distance Laplacian eigenvalue VERTEX-CONNECTIVITY independence number pendant vertices
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Statistical optimization of stress level in Mg-Li-Al alloys upon hot compression testing 被引量:6
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作者 Rezawana Islam Meysam Haghshenas 《Journal of Magnesium and Alloys》 SCIE EI CAS 2019年第2期203-217,共15页
In the present study,a response optimization method using Extreme Vertices Mixer Design(EVMD)approach is proposed for stress optimization in a thermomechanically processed Mg-Li-Al alloy.Experimentation was planned as... In the present study,a response optimization method using Extreme Vertices Mixer Design(EVMD)approach is proposed for stress optimization in a thermomechanically processed Mg-Li-Al alloy.Experimentation was planned as per mixed design proportions of Mg,Li and Al and process variables(i.e.temperature and strain rate).Each experiment has been performed under different conditions of factors proportions and process variables.The response,particularly stress has been considered for each experiment.The response is optimized to find an optimum condition when the contributing factors influence material characteristics in such a way,to achieve better strength,ductility and corrosion resistance.Estimated regression coefficient table for response has been observed to identify the important factors in this process and significantly high variance inflation factor has been observed.Most importantly,an optimum condition is achieved from this analysis which fulfills the experimental observations and theoretical assumptions. 展开更多
关键词 Mg-Li-Al alloy Design of experiments(DOE) Extreme vertices mixture design(EVMD) Stress optimization
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Probability Distribution of Ratio of China Aviation Network Edge Vertices Degree and Its Evolutionary Trace Based on Complex Network
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作者 Cheng Xiangjun Yang Fang Wei Liying 《Journal of Traffic and Transportation Engineering》 2024年第3期119-129,共11页
In order to reveal the complex network characteristics and evolution principle of China aviation network, the probability distribution and evolution trace of ratio of China aviation network edge vertices degree were s... In order to reveal the complex network characteristics and evolution principle of China aviation network, the probability distribution and evolution trace of ratio of China aviation network edge vertices degree were studied based on the statistics data of China civil aviation network in 1988, 1994, 2001, 2008 and 2015. According to the theory and method of complex network, the network system was constructed with the city where the airport was located as the network node and the route between cities as the edge of the network. Based on the statistical data, the ratio of edge vertices degree in China aviation network in 1988, 1994, 2001, 2008 and 2015 were calculated. Using the probability statistical analysis method and regression analysis approach, it was found that the ratio of edge vertices degree had linear probability distribution and the two parameters of the probability distribution had linear evolution trace. 展开更多
关键词 Complex network China aviation network ratio of edge vertices degree linear probability distribution linear evolution trace.
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Probability Distribution of China Aviation Network Average Degree of Edge Vertices and Its Evolutionary Trace Based on Complex Network
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作者 Cheng Xiangjun Zhang Chunyue Liang Yanping 《Journal of Traffic and Transportation Engineering》 2024年第2期51-62,共12页
In order to reveal the complex network characteristics and evolution principle of China aviation network, the probability distribution and evolution trace of average degree of edge vertices of China aviation network w... In order to reveal the complex network characteristics and evolution principle of China aviation network, the probability distribution and evolution trace of average degree of edge vertices of China aviation network were studied based on the statistics data of China civil aviation network in 1988, 1994, 2001, 2008 and 2015. According to the theory and method of complex network, the network system was constructed with the city where the airport was located as the network node and the route between cities as the edge of the network. Based on the statistical data, the average degrees of edge vertices in China aviation network in 1988, 1994, 2001, 2008 and 2015 were calculated. Using the probability statistical analysis method and regression analysis approach, it was found that the average degree of edge vertices had the probability distribution of normal function and the position parameters and scale parameters of the probability distribution had linear evolution trace. 展开更多
关键词 Complex network China aviation network average degree of edge vertices normal distribution linear evolution trace
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Stability and Generalization of Hypergraph Collaborative Networks
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作者 Michael K.Ng Hanrui Wu Andy Yip 《Machine Intelligence Research》 EI CSCD 2024年第1期184-196,共13页
Graph neural networks have been shown to be very effective in utilizing pairwise relationships across samples.Recently,there have been several successful proposals to generalize graph neural networks to hypergraph neu... Graph neural networks have been shown to be very effective in utilizing pairwise relationships across samples.Recently,there have been several successful proposals to generalize graph neural networks to hypergraph neural networks to exploit more com-plex relationships.In particular,the hypergraph collaborative networks yield superior results compared to other hypergraph neural net-works for various semi-supervised learning tasks.The collaborative network can provide high quality vertex embeddings and hyperedge embeddings together by formulating them as a joint optimization problem and by using their consistency in reconstructing the given hy-pergraph.In this paper,we aim to establish the algorithmic stability of the core layer of the collaborative network and provide generaliz--ation guarantees.The analysis sheds light on the design of hypergraph filters in collaborative networks,for instance,how the data and hypergraph filters should be scaled to achieve uniform stability of the learning process.Some experimental results on real-world datasets are presented to illustrate the theory. 展开更多
关键词 HYPERGRAPHS vertices hyperedges collaborative networks graph convolutional neural networks(CNNs) STABILITY generalization guarantees
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Probability Distribution of Arithmetic Average of China Aviation Network Edge Vertices Nearest Neighbor Average Degree Value and Its Evolutionary Trace Based on Complex Network
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作者 Cheng Xiangjun Yang Fang Xiong Zhihua 《Journal of Traffic and Transportation Engineering》 2024年第4期163-174,共12页
In order to reveal the complex network characteristics and evolution principle of China aviation network,the probability distribution and evolution trace of arithmetic average of edge vertices nearest neighbor average... In order to reveal the complex network characteristics and evolution principle of China aviation network,the probability distribution and evolution trace of arithmetic average of edge vertices nearest neighbor average degree values of China aviation network were studied based on the statistics data of China civil aviation network in 1988,1994,2001,2008 and 2015.According to the theory and method of complex network,the network system was constructed with the city where the airport was located as the network node and the route between cities as the edge of the network.Based on the statistical data,the arithmetic averages of edge vertices nearest neighbor average degree values of China aviation network in 1988,1994,2001,2008 and 2015 were calculated.Using the probability statistical analysis method,it was found that the arithmetic average of edge vertices nearest neighbor average degree values had the probability distribution of normal function and the position parameters and scale parameters of the probability distribution had linear evolution trace. 展开更多
关键词 Complex network China aviation network arithmetic average of edge vertices nearest neighbor average degree value linear evolution trace
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基于关联策略的CTR-GCN人体骨骼行为识别
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作者 刘廷龙 康斌 《计算机技术与发展》 2023年第10期42-46,共5页
针对骨骼的人体行为识别中表达人体的重要信息的关节点分区策略不能够充分表达行为的问题,提出了一种关联策略的CTR-GCN人体骨骼行为识别模型。首先,通过在智能信道拓扑的细化图卷积网络模型(CTR-GCN)上增加关联策略,能够动态地学习不... 针对骨骼的人体行为识别中表达人体的重要信息的关节点分区策略不能够充分表达行为的问题,提出了一种关联策略的CTR-GCN人体骨骼行为识别模型。首先,通过在智能信道拓扑的细化图卷积网络模型(CTR-GCN)上增加关联策略,能够动态地学习不同的拓扑结构和高效地在不同信道中放大连接点特征,同时提升关键关节点的关联特性;然后,网络模型通过学习一个共享的拓扑并且用特定的信道关系来重新定义每一个信道并通过理论分析统一模型;最后,重新定义模型结构。信道内部局部节点的关联信息得到有效体现,对细微的动作识别具有更强的聚合能力。提出的关联策略的智能信道拓扑图卷积网络模型(ASCTR-GCN)在基于智能拓扑细化卷积网络的基础上比CTR-GCN方法增强了关节点之间内在的关联性,大大提高了骨关节点信息在空间上的识别精度。实验结果表明,在常用的NTU RGB+D和NW-UCLA数据集中识别精度分别达到93.6%(X-View)、97.6%(X-Sub)、97.2%(Top 1),准确率得到提高。 展开更多
关键词 关节点 智能拓扑细化图卷积网络 关联策略 骨骼行为识别 特征提取
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Bézier曲线可降阶条件及其降阶逼近 被引量:3
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作者 刘庆生 《同济大学学报(自然科学版)》 EI CAS CSCD 北大核心 2001年第4期470-473,共4页
用一组递推式来判别一条n + 1次B啨zier曲线的可降阶条件 ,并在可降阶条件成立时构造出相应的低阶曲线 .另外 ,利用顶点位置的调整 ,给出一条降阶曲线逼近原曲线的方法 ,同时考虑了它们的误差 .
关键词 BÉZIER曲线 递推 降阶逼近 顶点 可降阶条件 可降价曲线 二次函数 多项式插值函数
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复杂网络中节点重要性Damage度量分析 被引量:4
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作者 王辉 赵文会 施佺 《南京理工大学学报》 EI CAS CSCD 北大核心 2012年第6期926-931,共6页
为从网络健壮性角度研究复杂网络中节点重要性指标Damage问题,理论分析了各类模拟网络包括Barabasi-Albert无标度网络、Erdos-Renyi随机网络以及树形网络上的Damage度量。实证分析了真实网络上Damage指标对于网络功能的影响以及Damage... 为从网络健壮性角度研究复杂网络中节点重要性指标Damage问题,理论分析了各类模拟网络包括Barabasi-Albert无标度网络、Erdos-Renyi随机网络以及树形网络上的Damage度量。实证分析了真实网络上Damage指标对于网络功能的影响以及Damage与度的相关性。通过统计分析比较了真实网络在面对Damage攻击及度攻击时的抵御能力。理论与实证分析结果表明:各类复杂网络中存在着数量不可忽视的Damage较大的节点;Damage是一种不可代替的衡量网络节点重要性的指标;Damage较大的节点对于真实网络的功能有重要影响。对于各种不同的网络,对比度攻击和Damage攻击过程,发现存在1个交叉点,在此点之前Damage攻击比度攻击更具破坏性。 展开更多
关键词 复杂网络 节点 Damage度量 健壮性 度攻击
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On Augmented Zagreb Index of Molecular Graphs 被引量:1
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作者 杜建伟 邵燕灵 孙晓玲 《Journal of Donghua University(English Edition)》 EI CAS 2015年第3期442-445,共4页
The augmented Zagreb index displays a good correlation with the formation heat of octanes and heptanes. The augmented Zagreb index of catacondensed hexagonal systems and molecular trees was discussed. By using the met... The augmented Zagreb index displays a good correlation with the formation heat of octanes and heptanes. The augmented Zagreb index of catacondensed hexagonal systems and molecular trees was discussed. By using the methods of analysis of graph structure and mathematical induction,the catacondensed hexagonal systems with extreme augmented Zagreb index were characterized.The lower bound for augmented Zagreb index of molecular trees with fixed numbers of pendent vertices was given,and the extremal trees were characterized. From these results,we can compare the formation heat of catacondensed hexagonal systems and molecular trees. 展开更多
关键词 augmented Zagreb index catacondensed hexagonal systems trees molecular trees pendent vertices
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SIMPLIFIED ORDER CONDITIONS OF SOME CANONICAL DIFFERENCE SCHEMES 被引量:1
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作者 Zhu Wen-jie Qin Meng-zhao(State Key Laboratory of Scientific and Engineering Computing,Computing Center, Academia Sinica, Beijing, China ) 《Journal of Computational Mathematics》 SCIE CSCD 1995年第1期1-19,共19页
The main purpose of this paper is to develop and simplify the general conditions for an s-stage explicit canonical difference scheme of q-th order, while the simplified order conditions for canonical RKN methods which... The main purpose of this paper is to develop and simplify the general conditions for an s-stage explicit canonical difference scheme of q-th order, while the simplified order conditions for canonical RKN methods which are applied to a special kind of second order ordinary differential equations are also obtained here. 展开更多
关键词 vertices Plant roots Product labeling Ordinary differential equations Sons Mathematical monotonicity Integration techniques
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基于时空影响域的地震网络动力学演化特征分析 被引量:3
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作者 赵海 张娅 +1 位作者 何璇 赵楠 《东北大学学报(自然科学版)》 EI CAS CSCD 北大核心 2015年第9期1232-1236,共5页
为了研究地震网络的动力学行为,基于时空影响域的地震网络,分析以大地震发生时间为基点的网络的拓扑特征演化.结果发现:大地震发生前网络的规模和熵值较小,模块度较大;大地震发生后网络的规模变大,熵值跳变到相对大的值,模块度值达到极... 为了研究地震网络的动力学行为,基于时空影响域的地震网络,分析以大地震发生时间为基点的网络的拓扑特征演化.结果发现:大地震发生前网络的规模和熵值较小,模块度较大;大地震发生后网络的规模变大,熵值跳变到相对大的值,模块度值达到极小值.同时分析了1992年地震网络的多参数拓扑特征演化,结果表明地震网络表现出一种内在的网络动力学行为.此外,发现从大地震发生前100 d开始网络模块度振荡出现极大值,熵值振荡出现极小值,并呈现很好的负相关性. 展开更多
关键词 地震网络 节点 模块度 演化
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基于最小惯性轴及链码的图像形状描述方法 被引量:3
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作者 李宗民 陆天波 +1 位作者 桑鑫焱 秦宝山 《通信学报》 EI CSCD 北大核心 2009年第4期1-5,共5页
提出了基于最小惯性轴及链码的结合方法,这种方法能够同时利用形状边界轮廓和区域信息,并利用由特征点和形状质心构成的特征三角形计算得出的三角隶属函数值作为重要特征值进行相似性计算。此方法对于形状的转换是不变的,对凹边形匹配... 提出了基于最小惯性轴及链码的结合方法,这种方法能够同时利用形状边界轮廓和区域信息,并利用由特征点和形状质心构成的特征三角形计算得出的三角隶属函数值作为重要特征值进行相似性计算。此方法对于形状的转换是不变的,对凹边形匹配是健壮的,通过实验对比,此方法具有较高的检索性能。 展开更多
关键词 最小惯性轴 多边形 顶点 质心
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Graphs with Pendant Vertices and <i>r</i>(<i>G</i>) &#8804;7
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作者 Haicheng Ma Shang Gao Danyang Li 《Journal of Applied Mathematics and Physics》 2020年第2期240-246,共7页
Let G be a graph of order n with vertex set V(G) = {v1, v2,…, vn}. the adjacency matrix of G is an n × n matrix A(G) = (aij)n×n, where aij is the number edges joining vi and vj in G. The eigenvalues λ1, λ... Let G be a graph of order n with vertex set V(G) = {v1, v2,…, vn}. the adjacency matrix of G is an n × n matrix A(G) = (aij)n×n, where aij is the number edges joining vi and vj in G. The eigenvalues λ1, λ2, λ3,…, λn, of A(G) are said to be the eigenvalues of the graph G and to form the spectrum of this graph. The number of nonzero eigenvalues and zero eigenvalues in the spectrum of G are called rank and nullity of the graph G, and are denoted by r(G) and η(G), respectively. It follows from the definitions that r(G) + η(G) = n. In this paper, by using the operation of multiplication of vertices, a characterization for graph G with pendant vertices and r(G) = 7 is shown, and then a characterization for graph G with pendant vertices and r(G) less than or equal to 7 is shown. 展开更多
关键词 ADJACENCY Matrix Rank NULLITY Multiplication of vertices
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A Non-Conventional Coloring of the Edges of a Graph
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作者 Sándor Szabó 《Open Journal of Discrete Mathematics》 2012年第4期119-124,共6页
Coloring the nodes of a graph is a commonly used technique to speed up clique search algorithms. Coloring the edges of the graph as a preconditioning method can also be used to speed up computations. In this paper we ... Coloring the nodes of a graph is a commonly used technique to speed up clique search algorithms. Coloring the edges of the graph as a preconditioning method can also be used to speed up computations. In this paper we will show that an unconventional coloring scheme of the edges leads to an NP-complete problem when one intends to determine the optimal number of colors. 展开更多
关键词 Maximum CLIQUE COLORING the vertices of a GRAPH COLORING the EDGES of GRAPH NP-COMPLETE Problems
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