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Graph neural network-based scheduling for multi-UAV-enabled communications in D2D networks
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作者 Pei Li Lingyi Wang +3 位作者 Wei Wu Fuhui Zhou Baoyun Wang Qihui Wu 《Digital Communications and Networks》 SCIE CSCD 2024年第1期45-52,共8页
In this paper,we jointly design the power control and position dispatch for Multi-Unmanned Aerial Vehicle(UAV)-enabled communication in Device-to-Device(D2D)networks.Our objective is to maximize the total transmission... In this paper,we jointly design the power control and position dispatch for Multi-Unmanned Aerial Vehicle(UAV)-enabled communication in Device-to-Device(D2D)networks.Our objective is to maximize the total transmission rate of Downlink Users(DUs).Meanwhile,the Quality of Service(QoS)of all D2D users must be satisfied.We comprehensively considered the interference among D2D communications and downlink transmissions.The original problem is strongly non-convex,which requires high computational complexity for traditional optimization methods.And to make matters worse,the results are not necessarily globally optimal.In this paper,we propose a novel Graph Neural Networks(GNN)based approach that can map the considered system into a specific graph structure and achieve the optimal solution in a low complexity manner.Particularly,we first construct a GNN-based model for the proposed network,in which the transmission links and interference links are formulated as vertexes and edges,respectively.Then,by taking the channel state information and the coordinates of ground users as the inputs,as well as the location of UAVs and the transmission power of all transmitters as outputs,we obtain the mapping from inputs to outputs through training the parameters of GNN.Simulation results verified that the way to maximize the total transmission rate of DUs can be extracted effectively via the training on samples.Moreover,it also shows that the performance of proposed GNN-based method is better than that of traditional means. 展开更多
关键词 Unmanned aerial vehicle D2 Dcommunication graph neural network Power control Position planning
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一类仙人掌图的D(2)-点可区别全染色
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作者 汪银芳 李沐春 王国兴 《吉林大学学报(理学版)》 CAS 北大核心 2024年第1期1-6,共6页
用数学归纳法和组合分析法给出最大度为3的仙人掌图G T的D(2)-点可区别全染色,进而得到χ_(2vt)(G T)≤6.结果表明,D(β)-VDTC猜想对最大度为3的仙人掌图成立.
关键词 仙人掌图 D(2)-点可区别全染色 D(2)-点可区别全色数
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On the 2-Domination Number of Complete Grid Graphs
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作者 Ramy Shaheen Suhail Mahfud Khames Almanea 《Open Journal of Discrete Mathematics》 2017年第1期32-50,共19页
A set D of vertices of a graph G = (V, E) is called k-dominating if every vertex v ∈V-D is adjacent to some k vertices of D. The k-domination number of a graph G, γk (G), is the order of a smallest k-dominating set ... A set D of vertices of a graph G = (V, E) is called k-dominating if every vertex v ∈V-D is adjacent to some k vertices of D. The k-domination number of a graph G, γk (G), is the order of a smallest k-dominating set of G. In this paper we calculate the k-domination number (for k = 2) of the product of two paths Pm × Pn for m = 1, 2, 3, 4, 5 and arbitrary n. These results were shown an error in the paper [1]. 展开更多
关键词 k-Dominating SET K-DOMINATION NUMBER 2-Dominating SET 2-Domination NUMBER CARTESIAN Product graphs PATHS
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Nomogram model including LATS2 expression was constructed to predict the prognosis of advanced gastric cancer after surgery
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作者 Nan Sun Bi-Bo Tan Yong Li 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第2期518-528,共11页
BACKGROUND Gastric cancer is a leading cause of cancer-related deaths worldwide.Prognostic assessments are typically based on the tumor-node-metastasis(TNM)staging system,which does not account for the molecular heter... BACKGROUND Gastric cancer is a leading cause of cancer-related deaths worldwide.Prognostic assessments are typically based on the tumor-node-metastasis(TNM)staging system,which does not account for the molecular heterogeneity of this disease.LATS2,a tumor suppressor gene involved in the Hippo signaling pathway,has been identified as a potential prognostic biomarker in gastric cancer.AIM To construct and validate a nomogram model that includes LATS2 expression to predict the survival prognosis of advanced gastric cancer patients following ra-dical surgery,and compare its predictive performance with traditional TNM staging.METHODS A retrospective analysis of 245 advanced gastric cancer patients from the Fourth Hospital of Hebei Medical University was conducted.The patients were divided into a training group(171 patients)and a validation group(74 patients)to deve-lop and test our prognostic model.The performance of the model was determined using C-indices,receiver operating characteristic curves,calibration plots,and decision curves.RESULTS The model demonstrated a high predictive accuracy with C-indices of 0.829 in the training set and 0.862 in the validation set.Area under the curve values for three-year and five-year survival prediction were significantly robust,suggesting an excellent discrimination ability.Calibration plots confirmed the high concordance between the predictions and actual survival outcomes.CONCLUSION We developed a nomogram model incorporating LATS2 expression,which significantly outperformed conven-tional TNM staging in predicting the prognosis of advanced gastric cancer patients postsurgery.This model may serve as a valuable tool for individualized patient management,allowing for more accurate stratification and im-proved clinical outcomes.Further validation in larger patient cohorts will be necessary to establish its generaliza-bility and clinical utility. 展开更多
关键词 Gastric cancer LATS2 Column line graph PROGNOSIS Advanced gastric cancer survival Molecular biomarkers Predictive analytics in oncology Survival analysis
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Schultz Polynomials and Their Topological Indices of Jahangir Graphs J2,m
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作者 Shaohui Wang Mohammad Reza Farahani +1 位作者 M. R. Rajesh Kanna R. Pradeep Kumar 《Applied Mathematics》 2016年第14期1632-1637,共6页
Let G = (V;E) be a simple connected graph. The Wiener index is the sum of distances between all pairs of vertices of a connected graph. The Schultz topological index is equal to and the Modified Schultz topological in... Let G = (V;E) be a simple connected graph. The Wiener index is the sum of distances between all pairs of vertices of a connected graph. The Schultz topological index is equal to and the Modified Schultz topological index is . In this paper, the Schultz, Modified Schultz polynomials and their topological indices of Jahangir graphs J<sub>2,m</sub> for all integer number m ≥ 3 are calculated. 展开更多
关键词 Molecular Topological Index Schultz Index Schultz Polynomials Jahangir graphs J2 m
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H- and H<sub>2</sub>-Cordial Labeling of Some Graphs
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作者 Freeda Selvanayagom Robinson S. Chellathurai 《Open Journal of Discrete Mathematics》 2012年第4期149-155,共7页
In this paper we prove that the join of two path graphs, two cycle graphs, Ladder graph and the tensor product are H2-cordial labeling. Further we prove that the join of two wheel graphs Wn and Wm, (mod 4) admits a H-... In this paper we prove that the join of two path graphs, two cycle graphs, Ladder graph and the tensor product are H2-cordial labeling. Further we prove that the join of two wheel graphs Wn and Wm, (mod 4) admits a H-cordial labeling. 展开更多
关键词 H-Cordial H2-Cordial JOIN of Two graphs Split graphs
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A Note on SK, SK<sub>1</sub>, SK<sub>2</sub>Indices of Interval Weighted Graphs
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作者 Semiha Başdaş Nurkahlı Şerife Büyükköse 《Advances in Linear Algebra & Matrix Theory》 2021年第1期14-20,共7页
In this study, the SK, SK<sub>1</sub> and SK<sub>2</sub> indices are defined on weighted graphs. Then, the SK, SK<sub>1</sub> and SK<sub>2</sub> indices are defined on i... In this study, the SK, SK<sub>1</sub> and SK<sub>2</sub> indices are defined on weighted graphs. Then, the SK, SK<sub>1</sub> and SK<sub>2</sub> indices are defined on interval weighted graphs. Their behaviors are investigated under some graph operations by using these definitions. 展开更多
关键词 SK Index SK1 Index SK2 Index Weighted graph Interval Weighted graph
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<i>L</i>(2,1)-Labeling of the Brick Product Graphs
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作者 Xiujun Zhang Hong Yang Hong Li 《Journal of Applied Mathematics and Physics》 2017年第8期1529-1536,共8页
A k-L(2,1)-labeling for a graph G is a function such that whenever and whenever u and v are at distance two apart. The λ-number for G, denoted by λ(G), is the minimum k over all k-L(2,1)-labelings of G. In this pape... A k-L(2,1)-labeling for a graph G is a function such that whenever and whenever u and v are at distance two apart. The λ-number for G, denoted by λ(G), is the minimum k over all k-L(2,1)-labelings of G. In this paper, we show that for or 11, which confirms Conjecture 6.1 stated in [X. Li, V. Mak-Hau, S. Zhou, The L(2,1)-labelling problem for cubic Cayley graphs on dihedral groups, J. Comb. Optim. (2013) 25: 716-736] in the case when or 11. Moreover, we show that? if 1) either (mod 6), m is odd, r = 3, or 2) (mod 3), m is even (mod 2), r = 0. 展开更多
关键词 graph LABELING BRICK Product graph L((2 1)-Labeling Frequency ASSIGNMENT Problem
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三类联图的2-距离和可区别边染色
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作者 王芹 杨超 +1 位作者 殷志祥 姚兵 《华中师范大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第2期178-183,共6页
该文探讨了C_(m)·P_(n)、C_(m)·S_(n)和C_(m)·K_(n)三类联图的2-距离和可区别边染色问题.根据联图的结构特点,利用组合分析法、反证法以及分类讨论思想,得到了这三类联图的2-距离和可区别边色数.结论表明三类联图的2-距... 该文探讨了C_(m)·P_(n)、C_(m)·S_(n)和C_(m)·K_(n)三类联图的2-距离和可区别边染色问题.根据联图的结构特点,利用组合分析法、反证法以及分类讨论思想,得到了这三类联图的2-距离和可区别边色数.结论表明三类联图的2-距离和可区别边色数均不超过Δ+2. 展开更多
关键词 边染色 2-距离和可区别边染色 联图
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一些特殊图的中间图的2-距离和可区别全染色
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作者 王同昕 杨超 姚兵 《兰州理工大学学报》 CAS 北大核心 2024年第3期156-161,共6页
为了进一步研究图的2-距离和可区别全染色问题,根据中间图的构造特点,通过构造染色函数,利用组合分析法得到了路,圈,星,扇,轮,双星以及轮环图的中间图的2-距离和可区别全色数.
关键词 全染色 2-距离和可区别全染色 中间图
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On Graphs with Equal Connected Domination and 2-connected Domination Numbers
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作者 CHEN Hong-yu ZHU Zhe-li 《Chinese Quarterly Journal of Mathematics》 CSCD 2010年第1期98-103,共6页
如果 S 是一个统治集合,导致的 subgraph 至多有 k 部件, V 的子集 S 被称为一个连接 k 的统治集合。G 的连接 k 的支配数字 kc (G) 是在 G 的所有最小的连接 k 的统治集合上拿的最小的集的势。在这份报纸,我们与相等的连接支配和 2-... 如果 S 是一个统治集合,导致的 subgraph 至多有 k 部件, V 的子集 S 被称为一个连接 k 的统治集合。G 的连接 k 的支配数字 kc (G) 是在 G 的所有最小的连接 k 的统治集合上拿的最小的集的势。在这份报纸,我们与相等的连接支配和 2-connected 支配数字描绘树和 unicyclic 图。 展开更多
关键词 连接支配数字 2-connected 支配数字 uni 周期的图
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双圈图的D(2)-点可区别边染色 被引量:1
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作者 贾秀卿 文飞 +1 位作者 李泽鹏 李沐春 《高校应用数学学报(A辑)》 北大核心 2023年第2期236-252,共17页
图G的一个正常k-边染色f满足对■u,v∈V(G),当d(u,v)≤2时都有S_(f)(u)≠S_(f)(v),其中S_(f)(v)={f(vw)|vw∈E(G)}表示顶点v的所有关联边上所染颜色构成的集合,则称f为图G的k-D(2)-点可区别边染色(简记为k-D(2)-VDEC),将其所需要颜色的... 图G的一个正常k-边染色f满足对■u,v∈V(G),当d(u,v)≤2时都有S_(f)(u)≠S_(f)(v),其中S_(f)(v)={f(vw)|vw∈E(G)}表示顶点v的所有关联边上所染颜色构成的集合,则称f为图G的k-D(2)-点可区别边染色(简记为k-D(2)-VDEC),将其所需要颜色的最小数k称为D(2)-点可区别边色数,简记为χ’_(2-vd)(G).结合Hall定理证明了最大度为△(G)的双圈图G都有χ’_(2-vd)(G)≤△(G)+2. 展开更多
关键词 双圈图 正常边染色 D(2)-点可区别边染色 D(2)-点可区别边色数
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笛卡儿积图的2-hued列表染色 被引量:1
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作者 刘丙雪 刘凤霞 《新疆大学学报(自然科学版)(中英文)》 CAS 2023年第1期30-35,共6页
给定图G的一个列表分配L,图G的一个(L,r)-染色,是一个正常染色c满足:每个顶点v都至少和min{d(v),r}种不同颜色的顶点相邻,并且c(v)属于L(v).图G的r-hued列表染色数,记为χL,r(G),是最小正整数k满足对于任意一个|L(v)|=k的列表分配L,图G... 给定图G的一个列表分配L,图G的一个(L,r)-染色,是一个正常染色c满足:每个顶点v都至少和min{d(v),r}种不同颜色的顶点相邻,并且c(v)属于L(v).图G的r-hued列表染色数,记为χL,r(G),是最小正整数k满足对于任意一个|L(v)|=k的列表分配L,图G有一个(L,r)-染色.最后证明了χL,2(P_(m)□P_(n))=4,并且确定了χL,2(P_(m)□C_(n))的范围. 展开更多
关键词 笛卡儿积图 2-hued列表染色
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Characterizing C6+P2-graphic Sequences
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作者 HU Li-li 《Chinese Quarterly Journal of Mathematics》 CSCD 2014年第2期238-243,共6页
For a given graph H, a graphic sequence π =(d1, d2, ···, dn) is said to be potentially H-graphic if π has a realization containing H as a subgraph. In this paper, we characterize the potentially C6+ P... For a given graph H, a graphic sequence π =(d1, d2, ···, dn) is said to be potentially H-graphic if π has a realization containing H as a subgraph. In this paper, we characterize the potentially C6+ P2-graphic sequences where C6+ P2 denotes the graph obtained from C6 by adding two adjacent edges to the three pairwise nonadjacent vertices of C6. Moreover, we use the characterization to determine the value of σ(C6+ P2, n). 展开更多
关键词 graph degree sequence potentially C6+ P2-graphic sequences
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容许对称群的有限2-弧传递图
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作者 张莉 王改霞 《新疆大学学报(自然科学版)(中英文)》 CAS 2023年第5期543-549,共7页
如果图Γ至少有一个2-弧且其自同构群在点集和2-弧集合上是传递的,则称该图为2-弧传递图.设G是基柱为交错群Ac(其中c≥5)的几乎单群,利用陪集图概念构造无平方因子阶的(G,2)-弧传递图.再通过分析自同构群和其点稳定子群的子群链结构,给... 如果图Γ至少有一个2-弧且其自同构群在点集和2-弧集合上是传递的,则称该图为2-弧传递图.设G是基柱为交错群Ac(其中c≥5)的几乎单群,利用陪集图概念构造无平方因子阶的(G,2)-弧传递图.再通过分析自同构群和其点稳定子群的子群链结构,给出了该类图的分类. 展开更多
关键词 对称图 无平方因子阶 2-弧传递图 自同构群
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不含短圈平面图的2-距离列表染色
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作者 俞家浩 陈敏 《浙江师范大学学报(自然科学版)》 CAS 2023年第4期368-378,共11页
图的染色理论在图论中有着重要的地位.主要运用权转移技巧,通过结构分析,研究了不含4-圈和5-圈的平面图的2-距离列表染色.降低了这类平面图的2-距离(Δ+4)-列表染色的最大度下界,证明了不含4-圈和5-圈且Δ≥12的平面图是2-距离(Δ+4)-... 图的染色理论在图论中有着重要的地位.主要运用权转移技巧,通过结构分析,研究了不含4-圈和5-圈的平面图的2-距离列表染色.降低了这类平面图的2-距离(Δ+4)-列表染色的最大度下界,证明了不含4-圈和5-圈且Δ≥12的平面图是2-距离(Δ+4)-列表可染的. 展开更多
关键词 平面图 2-距离染色 2-距离列表染色 权转移
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k-Factors and Spanning Subgraph in Graphs
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作者 WANG Zhi-guo ZHANG Yi 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2006年第1期143-147,共5页
在这份报纸,我们讨论了 k 因素和跨越的 subgraph,并且求婚一将导致一系列重要结论的 conjecture。
关键词 K因子 2-连接图 生成子图 图论
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无三角形IC-可平面图的线性2-荫度
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作者 闫清华 徐常青 《首都师范大学学报(自然科学版)》 2023年第5期1-5,共5页
设G为最大度为Δ的IC-可平面图。图G的线性2-荫度la_(2)(G)是将G分解为k个边不交森林的最小正整数k,其中森林的每个分支均为长至多为2的路。本文通过权转移方法研究了无三角形IC-可平面图的线性2-荫度,得到la_(2)(G)≤[△+1/2]+5。
关键词 IC-可平面图 线性2-荫度 权转移方法
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平方图的2-距离和可区别边染色
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作者 王芹 杨超 姚兵 《河南师范大学学报(自然科学版)》 CAS 北大核心 2023年第4期78-83,共6页
为了进一步研究图的2-距离和可区别边染色的问题.利用组合分析法、反证法以及分类讨论的思想,得到了路、圈、C_(n)∧P_(m)、C_(m)∧C_(n)、C_(n)∧P_(m)∧C_(k)等5类平方图的2-距离和可区别边色数,结果表明这5类平方图的2-距离和可区别... 为了进一步研究图的2-距离和可区别边染色的问题.利用组合分析法、反证法以及分类讨论的思想,得到了路、圈、C_(n)∧P_(m)、C_(m)∧C_(n)、C_(n)∧P_(m)∧C_(k)等5类平方图的2-距离和可区别边色数,结果表明这5类平方图的2-距离和可区别边色数均不超过Δ+2. 展开更多
关键词 边染色 2-距离和可区别边染色 平方图
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若干倍图的2-距离和可区别全染色
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作者 王同昕 杨超 +1 位作者 殷志祥 姚兵 《西北师范大学学报(自然科学版)》 CAS 北大核心 2023年第5期47-52,共6页
为了研究图的2-距离和可区别全染色问题,根据倍图的结构特点,通过组合分析法和构造染色函数法,得到了路、圈、星、扇、轮、完全二部图的倍图的2-距离和可区别全色数.
关键词 全染色 2-距离和可区别全染色 倍图 全色数 最大度
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