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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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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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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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基于Gabor滤波器的Graph Cuts右心室MR图像分割 被引量:2
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作者 马双 陆雪松 《计算机与数字工程》 2016年第6期1167-1170,共4页
在医学图像处理中,右心室分割在临床医学诊断和对病情的定量分析中有着越来越重要的意义。由于心脏MR图像右心室具有高变异、壁薄、边界不明显的特点,论文利用2D-Gabor对心脏图像进行滤波处理,得到特征图像,借助高斯混合模型融入到Graph... 在医学图像处理中,右心室分割在临床医学诊断和对病情的定量分析中有着越来越重要的意义。由于心脏MR图像右心室具有高变异、壁薄、边界不明显的特点,论文利用2D-Gabor对心脏图像进行滤波处理,得到特征图像,借助高斯混合模型融入到Graph cuts算法中,完成右心室MR图像的分割。相比于经典算法,该方法在稳定性及准确率上都有较好的效果。 展开更多
关键词 2D-Gabor graph CUTS 右心室分割
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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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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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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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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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Flexibility of Embeddings of a Halin Graph in the Torus
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作者 MA Deng-ju REN Han 《Chinese Quarterly Journal of Mathematics》 CSCD 2009年第1期20-26,共7页
在这份报纸,我们证明任何在花托嵌入一张 Halin 图(平面图的一种类型) 的脸宽度是一个,并且为在花托决定一张 Halin 图的所有 nonequivalent embeddings 的数字给一个公式。
关键词 嵌入 平面图 宽度
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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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图数据精确最短距离的隐私保护外包计算方案 被引量:1
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作者 于莹莹 丁红发 蒋合领 《计算机工程》 CAS CSCD 北大核心 2023年第9期158-171,共14页
社交网络、通信网络、生物蛋白等海量图数据应用广泛且包含大量个人隐私和商业敏感信息,通常需要对图数据加密并通过云计算提供安全高效的外包查询服务。然而,设计加密图数据上的高效精确最短距离外包计算方案既要保证隐私数据的高安全... 社交网络、通信网络、生物蛋白等海量图数据应用广泛且包含大量个人隐私和商业敏感信息,通常需要对图数据加密并通过云计算提供安全高效的外包查询服务。然而,设计加密图数据上的高效精确最短距离外包计算方案既要保证隐私数据的高安全性,又要提高加密查询等计算的效率,具有一定挑战性。提出一种基于二跳覆盖标记和加法同态的图数据精确最短距离查询外包计算方案。使用广度优先搜索修剪策略对二跳覆盖标记生成的原始标记集合进行预处理,减少预处理的标记数量并提高查询效率。基于加法同态加密和伪随机函数对标记集合进行加密处理并构造安全索引结构,保护图数据的节点和距离信息,实现加密图数据的精确最短距离查询。实验结果表明,该方案能正确进行加密图数据上精确最短距离的外包计算,在半诚实假设下满足随机预言模型下的IND-CPA安全和(L_(1),L_(2))安全,能有效保护图结构数据在外包计算中的隐私信息,在图数据加密和最短距离查询阶段相较现有同类方案分别降低了13.04%~24.24%和36.44%~46.13%的时间开销。 展开更多
关键词 图数据外包计算 最短距离查询 二跳覆盖标记 加法同态加密 隐私保护
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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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基于雷达图评价针刀治疗腰椎间盘突出症文献质量:系统评价再评价
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作者 石明鹏 王思乂 +8 位作者 丛林 李绍军 顾铭钰 陈一恒 庄明辉 银河 于杰 朱立国 李振华 《世界中医药》 CAS 2023年第3期331-337,共7页
目的:采用雷达图综合评价针刀治疗腰椎间盘突出症的系统评价/Meta分析文献质量,为Meta分析和临床治疗方案的制定提供参考依据。方法:计算机检索数据库以获得全面的文献,以“发表年份”“纳入的研究类型”“AMSTAR-2评分”“PRISMA评分... 目的:采用雷达图综合评价针刀治疗腰椎间盘突出症的系统评价/Meta分析文献质量,为Meta分析和临床治疗方案的制定提供参考依据。方法:计算机检索数据库以获得全面的文献,以“发表年份”“纳入的研究类型”“AMSTAR-2评分”“PRISMA评分”“发表偏倚的检验”“同质性高低”6个维度计算文献秩数,最终绘制雷达图以多元评价文献。结果:最终纳入9篇文献,各维度的平均分值分别为5.22、6.78、5.22、5.67、8.11、8.11。雷达图直观显示,2018年、2016年发表的2篇文献秩数最大,雷达图面积较大;2010年发表的1篇文献秩数最小,雷达图面积较小。结论:纳入的文献秩数和在27~52之间,秩数越高其文献参考意义也越大。导致文献质量差异的主要原因为未对研究预先制定计划,文献检索和筛选不规范,未阐述纳入研究类型的原因,纳入研究的偏倚风险考虑不当,未提及可能的利益冲突等,上述问题导致文献秩数较低,参考意义次之。尽管所纳入的Meta分析均显示针刀的总有效率优于其他疗法(均P<0.05),但文献质量较低,仍须今后的高质量证据来证实针刀是否比其他疗法更为有效。 展开更多
关键词 雷达图 针刀 腰椎间盘突出症 META分析 系统评价再评价 PRISMA评分 AMSTAR-2评分
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Deep Learning Accelerates the Discovery of Two- Dimensional Catalysts for Hydrogen Evolution Reaction 被引量:1
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作者 Sicheng Wu Zhilong Wang +2 位作者 Haikuo Zhang Junfei Cai Jinjin Li 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第1期138-144,共7页
Two-dimensional materials with active sites are expected to replace platinum as large-scale hydrogen production catalysts.However,the rapid discovery of excellent two-dimensional hydrogen evolution reaction catalysts ... Two-dimensional materials with active sites are expected to replace platinum as large-scale hydrogen production catalysts.However,the rapid discovery of excellent two-dimensional hydrogen evolution reaction catalysts is seriously hindered due to the long experiment cycle and the huge cost of high-throughput calculations of adsorption energies.Considering that the traditional regression models cannot consider all the potential sites on the surface of catalysts,we use a deep learning method with crystal graph convolutional neural networks to accelerate the discovery of high-performance two-dimensional hydrogen evolution reaction catalysts from two-dimensional materials database,with the prediction accuracy as high as 95.2%.The proposed method considers all active sites,screens out 38 high performance catalysts from 6,531 two-dimensional materials,predicts their adsorption energies at different active sites,and determines the potential strongest adsorption sites.The prediction accuracy of the two-dimensional hydrogen evolution reaction catalysts screening strategy proposed in this work is at the density-functional-theory level,but the prediction speed is 10.19 years ahead of the high-throughput screening,demonstrating the capability of crystal graph convolutional neural networks-deep learning method for efficiently discovering high-performance new structures over a wide catalytic materials space. 展开更多
关键词 crystal graph convolutional neural network deep learning hydrogen evolution reaction two-dimensional(2D)material
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