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Graph Attention Networks for Skin Lesion Classification with CNN-Driven Node Features
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作者 Ghadah Naif Alwakid Samabia Tehsin +3 位作者 Mamoona Humayun Asad Farooq Ibrahim Alrashdi Amjad Alsirhani 《Computers, Materials & Continua》 2026年第1期1964-1984,共21页
Skin diseases affect millions worldwide.Early detection is key to preventing disfigurement,lifelong disability,or death.Dermoscopic images acquired in primary-care settings show high intra-class visual similarity and ... Skin diseases affect millions worldwide.Early detection is key to preventing disfigurement,lifelong disability,or death.Dermoscopic images acquired in primary-care settings show high intra-class visual similarity and severe class imbalance,and occasional imaging artifacts can create ambiguity for state-of-the-art convolutional neural networks(CNNs).We frame skin lesion recognition as graph-based reasoning and,to ensure fair evaluation and avoid data leakage,adopt a strict lesion-level partitioning strategy.Each image is first over-segmented using SLIC(Simple Linear Iterative Clustering)to produce perceptually homogeneous superpixels.These superpixels form the nodes of a region-adjacency graph whose edges encode spatial continuity.Node attributes are 1280-dimensional embeddings extracted with a lightweight yet expressive EfficientNet-B0 backbone,providing strong representational power at modest computational cost.The resulting graphs are processed by a five-layer Graph Attention Network(GAT)that learns to weight inter-node relationships dynamically and aggregates multi-hop context before classifying lesions into seven classes with a log-softmax output.Extensive experiments on the DermaMNIST benchmark show the proposed pipeline achieves 88.35%accuracy and 98.04%AUC,outperforming contemporary CNNs,AutoML approaches,and alternative graph neural networks.An ablation study indicates EfficientNet-B0 produces superior node descriptors compared with ResNet-18 and DenseNet,and that roughly five GAT layers strike a good balance between being too shallow and over-deep while avoiding oversmoothing.The method requires no data augmentation or external metadata,making it a drop-in upgrade for clinical computer-aided diagnosis systems. 展开更多
关键词 graph neural network image classification DermaMNIST dataset graph representation
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Automatic Detection of Health-Related Rumors: A Dual-Graph Collaborative Reasoning Framework Based on Causal Logic and Knowledge Graph
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作者 Ning Wang Haoran Lyu Yuchen Fu 《Computers, Materials & Continua》 2026年第1期2163-2193,共31页
With the widespread use of social media,the propagation of health-related rumors has become a significant public health threat.Existing methods for detecting health rumors predominantly rely on external knowledge or p... With the widespread use of social media,the propagation of health-related rumors has become a significant public health threat.Existing methods for detecting health rumors predominantly rely on external knowledge or propagation structures,with only a few recent approaches attempting causal inference;however,these have not yet effectively integrated causal discovery with domain-specific knowledge graphs for detecting health rumors.In this study,we found that the combined use of causal discovery and domain-specific knowledge graphs can effectively identify implicit pseudo-causal logic embedded within texts,holding significant potential for health rumor detection.To this end,we propose CKDG—a dual-graph fusion framework based on causal logic and medical knowledge graphs.CKDG constructs a weighted causal graph to capture the implicit causal relationships in the text and introduces a medical knowledge graph to verify semantic consistency,thereby enhancing the ability to identify the misuse of professional terminology and pseudoscientific claims.In experiments conducted on a dataset comprising 8430 health rumors,CKDG achieved an accuracy of 91.28%and an F1 score of 90.38%,representing improvements of 5.11%and 3.29%over the best baseline,respectively.Our results indicate that the integrated use of causal discovery and domainspecific knowledge graphs offers significant advantages for health rumor detection systems.This method not only improves detection performance but also enhances the transparency and credibility of model decisions by tracing causal chains and sources of knowledge conflicts.We anticipate that this work will provide key technological support for the development of trustworthy health-information filtering systems,thereby improving the reliability of public health information on social media. 展开更多
关键词 Health rumor detection causal graph knowledge graph dual-graph fusion
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A Novel Unsupervised Structural Attack and Defense for Graph Classification
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作者 Yadong Wang Zhiwei Zhang +2 位作者 Pengpeng Qiao Ye Yuan Guoren Wang 《Computers, Materials & Continua》 2026年第1期1761-1782,共22页
Graph Neural Networks(GNNs)have proven highly effective for graph classification across diverse fields such as social networks,bioinformatics,and finance,due to their capability to learn complex graph structures.Howev... Graph Neural Networks(GNNs)have proven highly effective for graph classification across diverse fields such as social networks,bioinformatics,and finance,due to their capability to learn complex graph structures.However,despite their success,GNNs remain vulnerable to adversarial attacks that can significantly degrade their classification accuracy.Existing adversarial attack strategies primarily rely on label information to guide the attacks,which limits their applicability in scenarios where such information is scarce or unavailable.This paper introduces an innovative unsupervised attack method for graph classification,which operates without relying on label information,thereby enhancing its applicability in a broad range of scenarios.Specifically,our method first leverages a graph contrastive learning loss to learn high-quality graph embeddings by comparing different stochastic augmented views of the graphs.To effectively perturb the graphs,we then introduce an implicit estimator that measures the impact of various modifications on graph structures.The proposed strategy identifies and flips edges with the top-K highest scores,determined by the estimator,to maximize the degradation of the model’s performance.In addition,to defend against such attack,we propose a lightweight regularization-based defense mechanism that is specifically tailored to mitigate the structural perturbations introduced by our attack strategy.It enhances model robustness by enforcing embedding consistency and edge-level smoothness during training.We conduct experiments on six public TU graph classification datasets:NCI1,NCI109,Mutagenicity,ENZYMES,COLLAB,and DBLP_v1,to evaluate the effectiveness of our attack and defense strategies.Under an attack budget of 3,the maximum reduction in model accuracy reaches 6.67%on the Graph Convolutional Network(GCN)and 11.67%on the Graph Attention Network(GAT)across different datasets,indicating that our unsupervised method induces degradation comparable to state-of-the-art supervised attacks.Meanwhile,our defense achieves the highest accuracy recovery of 3.89%(GCN)and 5.00%(GAT),demonstrating improved robustness against structural perturbations. 展开更多
关键词 graph classification graph neural networks adversarial attack
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Interactive Dynamic Graph Convolution with Temporal Attention for Traffic Flow Forecasting
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作者 Zitong Zhao Zixuan Zhang Zhenxing Niu 《Computers, Materials & Continua》 2026年第1期1049-1064,共16页
Reliable traffic flow prediction is crucial for mitigating urban congestion.This paper proposes Attentionbased spatiotemporal Interactive Dynamic Graph Convolutional Network(AIDGCN),a novel architecture integrating In... Reliable traffic flow prediction is crucial for mitigating urban congestion.This paper proposes Attentionbased spatiotemporal Interactive Dynamic Graph Convolutional Network(AIDGCN),a novel architecture integrating Interactive Dynamic Graph Convolution Network(IDGCN)with Temporal Multi-Head Trend-Aware Attention.Its core innovation lies in IDGCN,which uniquely splits sequences into symmetric intervals for interactive feature sharing via dynamic graphs,and a novel attention mechanism incorporating convolutional operations to capture essential local traffic trends—addressing a critical gap in standard attention for continuous data.For 15-and 60-min forecasting on METR-LA,AIDGCN achieves MAEs of 0.75%and 0.39%,and RMSEs of 1.32%and 0.14%,respectively.In the 60-min long-term forecasting of the PEMS-BAY dataset,the AIDGCN out-performs the MRA-BGCN method by 6.28%,4.93%,and 7.17%in terms of MAE,RMSE,and MAPE,respectively.Experimental results demonstrate the superiority of our pro-posed model over state-of-the-art methods. 展开更多
关键词 Traffic flow prediction interactive dynamic graph convolution graph convolution temporal multi-head trend-aware attention self-attention mechanism
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GFL-SAR: Graph Federated Collaborative Learning Framework Based on Structural Amplification and Attention Refinement
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作者 Hefei Wang Ruichun Gu +2 位作者 Jingyu Wang Xiaolin Zhang Hui Wei 《Computers, Materials & Continua》 2026年第1期1683-1702,共20页
Graph Federated Learning(GFL)has shown great potential in privacy protection and distributed intelligence through distributed collaborative training of graph-structured data without sharing raw information.However,exi... Graph Federated Learning(GFL)has shown great potential in privacy protection and distributed intelligence through distributed collaborative training of graph-structured data without sharing raw information.However,existing GFL approaches often lack the capability for comprehensive feature extraction and adaptive optimization,particularly in non-independent and identically distributed(NON-IID)scenarios where balancing global structural understanding and local node-level detail remains a challenge.To this end,this paper proposes a novel framework called GFL-SAR(Graph Federated Collaborative Learning Framework Based on Structural Amplification and Attention Refinement),which enhances the representation learning capability of graph data through a dual-branch collaborative design.Specifically,we propose the Structural Insight Amplifier(SIA),which utilizes an improved Graph Convolutional Network(GCN)to strengthen structural awareness and improve modeling of topological patterns.In parallel,we propose the Attentive Relational Refiner(ARR),which employs an enhanced Graph Attention Network(GAT)to perform fine-grained modeling of node relationships and neighborhood features,thereby improving the expressiveness of local interactions and preserving critical contextual information.GFL-SAR effectively integrates multi-scale features from every branch via feature fusion and federated optimization,thereby addressing existing GFL limitations in structural modeling and feature representation.Experiments on standard benchmark datasets including Cora,Citeseer,Polblogs,and Cora_ML demonstrate that GFL-SAR achieves superior performance in classification accuracy,convergence speed,and robustness compared to existing methods,confirming its effectiveness and generalizability in GFL tasks. 展开更多
关键词 graph federated learning GCN GNNs attention mechanism
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Defect Identification Method of Power Grid Secondary Equipment Based on Coordination of Knowledge Graph and Bayesian Network Fusion
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作者 Jun Xiong Peng Yang +1 位作者 Bohan Chen Zeming Chen 《Energy Engineering》 2026年第1期296-313,共18页
The reliable operation of power grid secondary equipment is an important guarantee for the safety and stability of the power system.However,various defects could be produced in the secondary equipment during longtermo... The reliable operation of power grid secondary equipment is an important guarantee for the safety and stability of the power system.However,various defects could be produced in the secondary equipment during longtermoperation.The complex relationship between the defect phenomenon andmulti-layer causes and the probabilistic influence of secondary equipment cannot be described through knowledge extraction and fusion technology by existing methods,which limits the real-time and accuracy of defect identification.Therefore,a defect recognition method based on the Bayesian network and knowledge graph fusion is proposed.The defect data of secondary equipment is transformed into the structured knowledge graph through knowledge extraction and fusion technology.The knowledge graph of power grid secondary equipment is mapped to the Bayesian network framework,combined with historical defect data,and introduced Noisy-OR nodes.The prior and conditional probabilities of the Bayesian network are then reasonably assigned to build a model that reflects the probability dependence between defect phenomena and potential causes in power grid secondary equipment.Defect identification of power grid secondary equipment is achieved by defect subgraph search based on the knowledge graph,and defect inference based on the Bayesian network.Practical application cases prove this method’s effectiveness in identifying secondary equipment defect causes,improving identification accuracy and efficiency. 展开更多
关键词 Knowledge graph Bayesian network secondary equipment defect identification
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Graph-Based Intrusion Detection with Explainable Edge Classification Learning
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作者 Jaeho Shin Jaekwang Kim 《Computers, Materials & Continua》 2026年第1期610-635,共26页
Network attacks have become a critical issue in the internet security domain.Artificial intelligence technology-based detection methodologies have attracted attention;however,recent studies have struggled to adapt to ... Network attacks have become a critical issue in the internet security domain.Artificial intelligence technology-based detection methodologies have attracted attention;however,recent studies have struggled to adapt to changing attack patterns and complex network environments.In addition,it is difficult to explain the detection results logically using artificial intelligence.We propose a method for classifying network attacks using graph models to explain the detection results.First,we reconstruct the network packet data into a graphical structure.We then use a graph model to predict network attacks using edge classification.To explain the prediction results,we observed numerical changes by randomly masking and calculating the importance of neighbors,allowing us to extract significant subgraphs.Our experiments on six public datasets demonstrate superior performance with an average F1-score of 0.960 and accuracy of 0.964,outperforming traditional machine learning and other graph models.The visual representation of the extracted subgraphs highlights the neighboring nodes that have the greatest impact on the results,thus explaining detection.In conclusion,this study demonstrates that graph-based models are suitable for network attack detection in complex environments,and the importance of graph neighbors can be calculated to efficiently analyze the results.This approach can contribute to real-world network security analyses and provide a new direction in the field. 展开更多
关键词 Intrusion detection graph neural network explainable AI network attacks graphSAGE
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基于改进GraphSAGE的网络攻击检测
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作者 闫彦彤 于文涛 +1 位作者 李丽红 方伟 《郑州大学学报(理学版)》 北大核心 2026年第1期27-34,共8页
基于深度学习的网络攻击检测是对欧几里得数据进行建模,无法学习攻击数据中的结构特征。为此,提出一种基于改进图采样与聚合(graph sample and aggregate,GraphSAGE)的网络攻击检测算法。首先,将攻击数据从平面结构转换为图结构数据。其... 基于深度学习的网络攻击检测是对欧几里得数据进行建模,无法学习攻击数据中的结构特征。为此,提出一种基于改进图采样与聚合(graph sample and aggregate,GraphSAGE)的网络攻击检测算法。首先,将攻击数据从平面结构转换为图结构数据。其次,对GraphSAGE算法进行了改进,包括在消息传递阶段融合节点和边的特征,同时在消息聚合过程中考虑不同源节点对目标节点的影响程度,并在边嵌入生成时引入残差学习机制。在两个公开网络攻击数据集上的实验结果表明,在二分类情况下,所提算法的总体性能优于E-GraphSAGE、LSTM、RNN、CNN算法;在多分类情况下,所提算法在大多数攻击类型上的F1值高于对比算法。 展开更多
关键词 网络攻击检测 深度学习 图神经网络 图采样与聚合 注意力机制
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Graph-Based Unified Settlement Framework for Complex Electricity Markets:Data Integration and Automated Refund Clearing
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作者 Xiaozhe Guo Suyan Long +4 位作者 Ziyu Yue Yifan Wang Guanting Yin Yuyang Wang Zhaoyuan Wu 《Energy Engineering》 2026年第1期56-90,共35页
The increasing complexity of China’s electricity market creates substantial challenges for settlement automation,data consistency,and operational scalability.Existing provincial settlement systems are fragmented,lack... The increasing complexity of China’s electricity market creates substantial challenges for settlement automation,data consistency,and operational scalability.Existing provincial settlement systems are fragmented,lack a unified data structure,and depend heavily on manual intervention to process high-frequency and retroactive transactions.To address these limitations,a graph-based unified settlement framework is proposed to enhance automation,flexibility,and adaptability in electricity market settlements.A flexible attribute-graph model is employed to represent heterogeneousmulti-market data,enabling standardized integration,rapid querying,and seamless adaptation to evolving business requirements.An extensible operator library is designed to support configurable settlement rules,and a suite of modular tools—including dataset generation,formula configuration,billing templates,and task scheduling—facilitates end-to-end automated settlement processing.A robust refund-clearing mechanism is further incorporated,utilizing sandbox execution,data-version snapshots,dynamic lineage tracing,and real-time changecapture technologies to enable rapid and accurate recalculations under dynamic policy and data revisions.Case studies based on real-world data from regional Chinese markets validate the effectiveness of the proposed approach,demonstrating marked improvements in computational efficiency,system robustness,and automation.Moreover,enhanced settlement accuracy and high temporal granularity improve price-signal fidelity,promote cost-reflective tariffs,and incentivize energy-efficient and demand-responsive behavior among market participants.The method not only supports equitable and transparent market operations but also provides a generalizable,scalable foundation for modern electricity settlement platforms in increasingly complex and dynamic market environments. 展开更多
关键词 Electricity market market settlement data model graph database market refund clearing
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UGEA-LMD: A Continuous-Time Dynamic Graph Representation Enhancement Framework for Lateral Movement Detection
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作者 Jizhao Liu Yuanyuan Shao +2 位作者 Shuqin Zhang Fangfang Shan Jun Li 《Computers, Materials & Continua》 2026年第1期1924-1943,共20页
Lateral movement represents the most covert and critical phase of Advanced Persistent Threats(APTs),and its detection still faces two primary challenges:sample scarcity and“cold start”of new entities.To address thes... Lateral movement represents the most covert and critical phase of Advanced Persistent Threats(APTs),and its detection still faces two primary challenges:sample scarcity and“cold start”of new entities.To address these challenges,we propose an Uncertainty-Driven Graph Embedding-Enhanced Lateral Movement Detection framework(UGEA-LMD).First,the framework employs event-level incremental encoding on a continuous-time graph to capture fine-grained behavioral evolution,enabling newly appearing nodes to retain temporal contextual awareness even in the absence of historical interactions and thereby fundamentally mitigating the cold-start problem.Second,in the embedding space,we model the dependency structure among feature dimensions using a Gaussian copula to quantify the uncertainty distribution,and generate augmented samples with consistent structural and semantic properties through adaptive sampling,thus expanding the representation space of sparse samples and enhancing the model’s generalization under sparse sample conditions.Unlike static graph methods that cannot model temporal dependencies or data augmentation techniques that depend on predefined structures,UGEA-LMD offers both superior temporaldynamic modeling and structural generalization.Experimental results on the large-scale LANL log dataset demonstrate that,under the transductive setting,UGEA-LMD achieves an AUC of 0.9254;even when 10%of nodes or edges are withheld during training,UGEA-LMD significantly outperforms baseline methods on metrics such as recall and AUC,confirming its robustness and generalization capability in sparse-sample and cold-start scenarios. 展开更多
关键词 Advanced persistent threat(APTs) lateral movement detection continuous-time dynamic graph data enhancement
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基于DAG-DCC-GARCH的资本市场间瞬时风险传导机制研究
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作者 方茜 杨楠 《数理统计与管理》 北大核心 2025年第4期723-742,共20页
与目前广泛研究的基于长期稳态的风险传导不同,本文提出基于动态条件相关广义自回归条件异方差的有向无环图(DAG-DCC-GARCH)模型,来定量刻画资本市场间的日度瞬时风险传导机制,尤其关注风险事件发生后市场剧烈波动情形下资本市场风险传... 与目前广泛研究的基于长期稳态的风险传导不同,本文提出基于动态条件相关广义自回归条件异方差的有向无环图(DAG-DCC-GARCH)模型,来定量刻画资本市场间的日度瞬时风险传导机制,尤其关注风险事件发生后市场剧烈波动情形下资本市场风险传导机制的变化。首先,采用DCC-GARCH计算动态相关系数矩阵,然后,由此构建反映日频同期因果关系的时变有向无环图(DAG),采用拔靴(Bootstrap)法进行相关系数和偏相关系数的显著性检验,获得的日度瞬时有向无环图刻画了资本市场间的瞬时风险传导机制。实证结果显示,中美两国的股市和黄金市场均为主要的瞬时风险外溢方。整体市场风险水平越高,资本市场间的风险外溢强度越低,体现出两国在系统性风险防范方面具有一定的成效。中国市场的瞬时风险传导强度高于美国市场,且逐年增加,同时美国的各市场瞬时风险传导属性较中国市场更为稳定。在以新冠疫情初期爆发初期为代表的事件冲击研究中,两国整体瞬时风险传导能力在事件发生后逐步降低,股票市场表现出相对更强的风险外溢能力。 展开更多
关键词 瞬时风险传导机制 DCC-GARCH dag 拔靴(Bootstrap)相关系数显著性检验 资本市场
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基于GraphRAG的大数据知识学习系统
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作者 王晓燕 黄岚 王岩 《吉林大学学报(理学版)》 北大核心 2025年第6期1629-1636,共8页
针对大数据教学资源爆炸导致的信息过载与传统检索增强生成(RAG)在多源信息融合时准确性不足的问题,提出一种基于GraphRAG的大数据知识学习方法.首先,设计中文提示模板,驱动GraphRAG自动抽取课程实体和关系,构建初始知识图谱并持久化至N... 针对大数据教学资源爆炸导致的信息过载与传统检索增强生成(RAG)在多源信息融合时准确性不足的问题,提出一种基于GraphRAG的大数据知识学习方法.首先,设计中文提示模板,驱动GraphRAG自动抽取课程实体和关系,构建初始知识图谱并持久化至Neo4j图数据库;其次,通过实体对齐和关系补全,将人工整理的知识点与自动构建的图谱相融合,形成统一、可演化的知识图谱库;最后,利用GraphRAG预生成的社区摘要实现全局语义搜索,同时依托Neo4j图数据库完成面向知识点的局部精准检索.实验结果表明,该方法在问答准确率、响应相关性和多源信息整合流畅度上均显著优于传统RAG. 展开更多
关键词 大语言模型 检索增强生成 图检索增强生成 知识图谱
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一种新的异构多核平台下多类型DAG调度方法 被引量:1
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作者 左俊杰 肖锋 +3 位作者 黄姝娟 沈超 郝鹏涛 陈磊 《计算机应用研究》 北大核心 2025年第2期514-518,共5页
异构多核处理器在异构环境中受限于处理器种类,只能在特定处理器上执行。现有调度方法通常使用多类型DAG(directed acyclic graph)任务模型进行模拟,但调度方法往往忽略不同核上的通信开销,或未考虑处理器与节点的对应关系,导致调度时... 异构多核处理器在异构环境中受限于处理器种类,只能在特定处理器上执行。现有调度方法通常使用多类型DAG(directed acyclic graph)任务模型进行模拟,但调度方法往往忽略不同核上的通信开销,或未考虑处理器与节点的对应关系,导致调度时间开销较大,处理器资源未充分利用,任务效率低。针对上述问题,提出了PNIF(processor-node impact factor)算法。该算法引入了两个对节点优先级具有重大影响的比例因子,将它们加入到节点优先级的计算中从而确定任务执行顺序。实验结果表明,PNIF比PEFT、HEFT、CPOP在调度长度上分别平均提升5.902%、19.402%、25.831%,有效缩短了整体调度长度,提升了处理器资源利用率。 展开更多
关键词 异构多核处理器 多类型dag任务 任务调度 影响因子 PNIF算法
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Graph Transformer技术与研究进展:从基础理论到前沿应用 被引量:2
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作者 游浩 丁苍峰 +2 位作者 马乐荣 延照耀 曹璐 《计算机应用研究》 北大核心 2025年第4期975-986,共12页
图数据处理是一种用于分析和操作图结构数据的方法,广泛应用于各个领域。Graph Transformer作为一种直接学习图结构数据的模型框架,结合了Transformer的自注意力机制和图神经网络的方法,是一种新型模型。通过捕捉节点间的全局依赖关系... 图数据处理是一种用于分析和操作图结构数据的方法,广泛应用于各个领域。Graph Transformer作为一种直接学习图结构数据的模型框架,结合了Transformer的自注意力机制和图神经网络的方法,是一种新型模型。通过捕捉节点间的全局依赖关系和精确编码图的拓扑结构,Graph Transformer在节点分类、链接预测和图生成等任务中展现出卓越的性能和准确性。通过引入自注意力机制,Graph Transformer能够有效捕捉节点和边的局部及全局信息,显著提升模型效率和性能。深入探讨Graph Transformer模型,涵盖其发展背景、基本原理和详细结构,并从注意力机制、模块架构和复杂图处理能力(包括超图、动态图)三个角度进行细分分析。全面介绍Graph Transformer的应用现状和未来发展趋势,并探讨其存在的问题和挑战,提出可能的改进方法和思路,以推动该领域的研究和应用进一步发展。 展开更多
关键词 图神经网络 graph Transformer 图表示学习 节点分类
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Bondage Number of 1-Planar Graph 被引量:1
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作者 Qiaoling Ma Sumei Zhang Jihui Wang 《Applied Mathematics》 2010年第2期101-103,共3页
The bondage number of a nonempty graph G is the cardinality of a smallest set of edges whose removal from G results in a graph a domination number greater than the domination number of G. In this paper, we prove that ... The bondage number of a nonempty graph G is the cardinality of a smallest set of edges whose removal from G results in a graph a domination number greater than the domination number of G. In this paper, we prove that for a 1-planar graph G. 展开更多
关键词 DOMINATION NUMBER Bondage NUMBER 1-Planar graph Combinatorial PROBLEM
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基于DAGs法的本科实习护生监护能力影响因素研究
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作者 郭瑞红 王永芳 《中国高等医学教育》 2025年第10期67-69,共3页
目的:评估本科实习护生的监护能力,并运用DAGs方法分析专业设置及临床实习环节对该能力的影响,为教学改革提供依据。方法:于2023年4月采用便利抽样法选取我校实习护生为研究对象,使用一般资料问卷和危重症监护护理能力量表(ICCN-CS-1)... 目的:评估本科实习护生的监护能力,并运用DAGs方法分析专业设置及临床实习环节对该能力的影响,为教学改革提供依据。方法:于2023年4月采用便利抽样法选取我校实习护生为研究对象,使用一般资料问卷和危重症监护护理能力量表(ICCN-CS-1)进行调查。结果:共回收有效问卷145份,护生监护能力得分为(3.70±0.54)分,处于良好水平。多元线性回归分析显示,急诊/ICU实习时长与参与抢救次数为护生监护能力的显著影响因素(P<0.01),专业方向设置呈边缘显著(P=0.06)。结论:增加急诊/ICU实习时长并提供参与抢救病人的机会,有助于提升实习护生的监护能力。 展开更多
关键词 有向无环图 本科实习护生 监护能力
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基于HoneyBadgerBFT和DAG的异步网络区块链分片机制
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作者 陈宇轩 郑海彬 +3 位作者 关振宇 苏泊衡 王玉珏 郭振纬 《计算机应用》 北大核心 2025年第7期2092-2100,共9页
针对区块链系统在扩展性方面存在的网络规模受限、网络环境强依赖、存储成本高以及交易吞吐量低下等问题,提出一种适应异步网络环境并且支持交易并行处理的分片机制。该机制采用HoneyBadgerBFT共识在异步网络环境下达成数据一致性,通过... 针对区块链系统在扩展性方面存在的网络规模受限、网络环境强依赖、存储成本高以及交易吞吐量低下等问题,提出一种适应异步网络环境并且支持交易并行处理的分片机制。该机制采用HoneyBadgerBFT共识在异步网络环境下达成数据一致性,通过分片技术实现区块链系统的线性扩展,并通过DAG(Directed Acyclic Graph)技术进一步增强片内交易及不相交跨片交易的并行处理能力。仿真结果表明,所提机制在异步网络环境下仍能保持活性;在半同步网络环境中,所提机制的通信开销比使用拜占庭容错协议(PBFT)的SharPer降低超过49.9%;在由16个节点组成的区块链网络中,所提机制的TPS(Transactions-Per-Second)与SharPer相比少16.7%,而在64个节点组成的区块链网络中,所提机制的TPS比SharPer高6.7%,表明所提机制拥有比SharPer更高的吞吐量;在含有20%跨片交易且使用相同网络环境及硬件资源的条件下,所提机制的分片数及节点数每扩大1倍,该机制交易吞吐量增长比SharPer分别多30.0%和10.5%,表明所提机制拥有比SharPer更好的扩展性。 展开更多
关键词 区块链 分片 异步网络 HoneyBadgerBFT dag
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车联网中基于DAG区块链的改进PBFT共识机制
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作者 孙英伦 范艳芳 +2 位作者 张哲 许乃荻 陈若愚 《北京信息科技大学学报(自然科学版)》 2025年第2期35-43,共9页
针对车联网环境下有向无环图(directed acyclic graph,DAG)区块链系统中存在的事务验证延迟和共识容错性不足的问题,提出了一种基于信誉的实用拜占庭容错(practical Byzantine fault tolerance,PBFT)共识机制。将PBFT共识机制引入DAG区... 针对车联网环境下有向无环图(directed acyclic graph,DAG)区块链系统中存在的事务验证延迟和共识容错性不足的问题,提出了一种基于信誉的实用拜占庭容错(practical Byzantine fault tolerance,PBFT)共识机制。将PBFT共识机制引入DAG区块链,结合网络分片方法,确保共识并行执行,在确保DAG区块链高吞吐量的同时,实现了先验证后上链,从而保障了事务的实时验证。针对分片后可能出现的节点数量不足,导致共识组易受攻击的问题,引入信誉机制,通过节点信誉进行分权共识,从而提高共识容错率。仿真实验结果表明,该方案不仅具备DAG区块链高吞吐量的优点,而且支持事务实时验证,增强了PBFT共识机制的容错能力。 展开更多
关键词 车联网 区块链 共识机制 有向无环图 实用拜占庭容错
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Bondage and Reinforcement Number of γ_f for Complete Multipartite Graph
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作者 陈学刚 孙良 马德香 《Journal of Beijing Institute of Technology》 EI CAS 2003年第1期89-91,共3页
The bondage number of γ f, b f(G) , is defined to be the minimum cardinality of a set of edges whose removal from G results in a graph G′ satisfying γ f(G′)> γ f(G) . The reinforcement number of γ f, ... The bondage number of γ f, b f(G) , is defined to be the minimum cardinality of a set of edges whose removal from G results in a graph G′ satisfying γ f(G′)> γ f(G) . The reinforcement number of γ f, r f(G) , is defined to be the minimum cardinality of a set of edges which when added to G results in a graph G′ satisfying γ f(G′)< γ f(G) . G.S.Domke and R.C.Laskar initiated the study of them and gave exact values of b f(G) and r f(G) for some classes of graphs. Exact values of b f(G) and r f(G) for complete multipartite graphs are given and some results are extended. 展开更多
关键词 fractional domination number bondage number reinforcement number complete multipartite graph
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有向无环图(DAG)架构在影视特效与后期制作中的应用研究 被引量:1
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作者 王璇 周辉 《现代电影技术》 2025年第4期13-19,共7页
针对影视特效与后期制作中传统工作流因依赖关系复杂化导致的效率低下问题,本研究探讨了有向无环图(DAG)架构的核心特性及其在任务调度与计算优化中的应用价值,并提出一种跨软件的全流程统一任务调度框架,以解决行业协作与资源管理的关... 针对影视特效与后期制作中传统工作流因依赖关系复杂化导致的效率低下问题,本研究探讨了有向无环图(DAG)架构的核心特性及其在任务调度与计算优化中的应用价值,并提出一种跨软件的全流程统一任务调度框架,以解决行业协作与资源管理的关键瓶颈。通过分析Houdini、Maya、Nuke等主流数字内容创作(DCC)软件的DAG架构,研究其在任务调度、并行计算与动态扩展方面的实现方式,并结合影视制作全流程需求,设计基于DAG的统一框架,涉及通用数据标准、全局任务调度引擎与资源库等,同时采用Kahn算法实现拓扑排序与动态依赖管理。总体而言,DAG架构凭借其无环依赖、拓扑排序与动态扩展能力,为影视制作提供了高效的任务调度与计算优化方案,未来仍需进一步解决跨软件兼容性与标准化问题,并结合AI与云原生技术,最终实现全流程自动化,为影视工业化发展提供技术支撑。 展开更多
关键词 有向无环图(dag) 影视特效 后期制作 全局任务调度 动态依赖管理
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