Dear Editor,This letter addresses the critical challenge of preserving privacy in graph learning without compromising on data utility.Differential privacy(DP)is emerging as an effective method for privacy-preserving g...Dear Editor,This letter addresses the critical challenge of preserving privacy in graph learning without compromising on data utility.Differential privacy(DP)is emerging as an effective method for privacy-preserving graph learning.However,its application often diminishes data utility,especially for nodes with fewer neighbors in graph neural networks(GNNs).展开更多
Dear Editor,This letter presents a novel graph neural network, namely modularized graph convolution network(MGCN), to address the underexplored issue in graph convolution networks(GCNs), wherein the weights for neighb...Dear Editor,This letter presents a novel graph neural network, namely modularized graph convolution network(MGCN), to address the underexplored issue in graph convolution networks(GCNs), wherein the weights for neighbor aggregation are fixed, leading to the limited capability of capturing diverse relationships among nodes for representation learning. Conventional GCNs always learn node representations in the graph according to the weights computed from the graph Laplacian, consequently overlooking the similarity and group cohesiveness of node features.展开更多
In the field of video scene graph generation,spatio-temporal feature extraction and the long-tail effect in relationship classification are core research issues.This paper proposes extracting spatio-temporal features ...In the field of video scene graph generation,spatio-temporal feature extraction and the long-tail effect in relationship classification are core research issues.This paper proposes extracting spatio-temporal features using the global-local Transformer model for video scene graph generation.Methods based on the Transformer architecture and attention mechanism enrich the semantic information of spatio-temporal features in videos,thereby improving the accuracy of relationship classification.In the feature processing module,pose features are introduced to strengthen the semantic representation of objects.In the spatial feature encoding module,a local spatial visibility matrix based on bounding boxes and key points of human pose features is proposed to add the issue of insufficient attention to local details in traditional Transformer encoders.In the temporal feature encoding module,a global random frame extraction strategy is proposed,which considers global temporal features while also taking computational complexity into account.In the relation classification module,to address the uneven distribution of object and relation categories in the Action Genome dataset,a relation classification loss function based on bipartite graph matching and Focal Loss is proposed,which alleviates the long-tail effect in relation classification and improves the accuracy.展开更多
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
In complex network analysis,node ranking is vital for propagation prediction,structural optimization,and intervention strategy design,yet existing methods often fail to effectively integrate community information in d...In complex network analysis,node ranking is vital for propagation prediction,structural optimization,and intervention strategy design,yet existing methods often fail to effectively integrate community information in dynamic settings.To address this,this paper proposes a node ranking method that combines graph attention mechanisms with contrastive learning.Community detection is employed to extract node-level community features,and a joint embedding module is designed to fuse global and local structures,thereby incorporating community information into node representations.Based on this,a multi-layer graph attention network adaptively learns node and neighborhood features,while contrastive learning mitigates interference from dynamic evolution and strengthens the model's ability to capture multi-scale structural differences.Experiments on multiple dynamic network datasets show that the proposed method significantly outperforms existing approaches in ranking accuracy,particularly in networks with higher average degrees and clearer community structures.These results validate the effectiveness of the method in enhancing feature representation and modeling multi-scale dynamic node influence.展开更多
Few-shot knowledge graph completion refers to inferring missing entity using limited instances.A key challenge lies in entity representation,which is complicated by diverse neighbor attributes.Although the entity'...Few-shot knowledge graph completion refers to inferring missing entity using limited instances.A key challenge lies in entity representation,which is complicated by diverse neighbor attributes.Although the entity's neighborhood topology holds potential to address this,its significance is overlooked in current research.In this paper,we propose a structure-aware graph attention network for few-shot knowledge graph completion.Firstly,to enhance entity representations,we design a structure-aware graph attention encoder to capture the graph's structural features of nodes,generating embedding for entity pairs.Secondly,a semantic prototype matching network is employed to compute the prediction score.Experiments on the NELL-One and Wiki-One datasets show that our proposed model outperforms the best baseline models by 0.021,0.026,0.039,0.032 and 0.016,0.064,0.043,0.040 in terms of MRR,Hits@10,Hits@5,and Hits@1 metrics,respectively.This demonstrates that our model can effectively leverage neighborhood topological information to improve the accuracy of knowledge completion,and achieve a better generalization.展开更多
Transformers have been widely applied to hyperspectral image classification,leveraging their self-attention mechanism for powerful global modelling.However,two key challenges remain as follows:excessive memory and com...Transformers have been widely applied to hyperspectral image classification,leveraging their self-attention mechanism for powerful global modelling.However,two key challenges remain as follows:excessive memory and computational costs from calculating correlations between all tokens(especially as image size or spectral bands increase)and limited ability to model local boundary information due to lacking explicit enhancement mechanisms.This paper proposes a novel method,bridge transformer network fused with deep graph convolution(BTDGC),to address these issues.The framework includes three components as follows:a double random masking mechanism(DRMM)that forces the model to infer masked features from context during training,a bridge transformer(BT)module with bridge tokens for cross-region feature interaction and a Deep Graph Convolutional Pooling(DGCP)module that preserves spatial topology while aggregating hierarchical information.Experiments on standard hyperspectral datasets show BTDGC outperforms mainstream methods in classification accuracy and robustness,effectively balancing global modelling and local boundary representation.The code is available at http://gffzz188fe103f8f1460aspovbw6oqw59q6nuc.ffgz.tsg.suse.edu.cn/jenny3489/BTDGC.展开更多
Traffic flow prediction is of great importance in traffic planning,road resource management,and congestion mitigation.However,existing prediction have significant limitations in modeling multi-scale spatial-temporal f...Traffic flow prediction is of great importance in traffic planning,road resource management,and congestion mitigation.However,existing prediction have significant limitations in modeling multi-scale spatial-temporal features,particularly in capturing temporal periodicity and spatial dependency in dynamically evolving traffic networks.This paper proposes a novel framework of traffic flow prediction,referred to as Adaptive Graph Fusion Dual-scale Convolutional Network(AGFDCN),which integrates spatial-temporal dynamic graphs with dual-scale convolutional networks.Specifically,we introduce a Dual-Scale Temporal Network,which combines long-and short-term dilated causal convolutions with a temporal decay-aware attention mechanism to efficiently capture traffic patterns across multiple temporal scales.Furthermore,we design a Dynamic Adaptive Graph Module,which models complex spatial dependencies in traffic networks through an adaptive graph fusion mechanism and a dual-path attention-gated module.Finally,the temporal and spatial representations are integrated by employing a gated fusion mechanism,enhancing the overall prediction performance.Experimental results obtained based on three highway datasets(i.e.,PEMS04,PEMS07 and PEMS08)verify that the proposed model outperforms several state-of-the-art baselines in various evaluation metrics.Compared to the spatial-temporal graph model AGCRN with best performance in the baseline models,the proposed model exhibits significant improvements across all datasets:it achieves reduces of MAE by 42.07%and RMSE by 35.43%on PEMS04;MAE by 28.35%and RMSE by 29.28%on PEMS07;and MAE by 30.52%and RMSE by 30.73%on PEMS08,respectively,validating its effectiveness in modeling complex spatial-temporal traffic data and its robustness in handling sudden traffic changes.展开更多
Tunnel environments often suffer from GPS denial,uneven illumination,and structural uniformity,which lead to feature degradation,loop closure failure,and long-distance drift in SLAM systems.To solve these problems,thi...Tunnel environments often suffer from GPS denial,uneven illumination,and structural uniformity,which lead to feature degradation,loop closure failure,and long-distance drift in SLAM systems.To solve these problems,this study aims to propose a high-precision SLAM method suitable for tunnel structural health monitoring.Firstly,an ABA-CLAHE image enhancement algorithm is proposed,which adopts cascaded processing of nonlinear brightness adjustment in HSV space and CLAHE local contrast optimization to improve low-light image quality and enhance feature stability.Then,SURF feature matching combined with the RANSAC algorithm is used to ensure feature matching accuracy.Finally,a factor graph model is constructed by integrating IMU pre-integration,laser odometry,visual odometry,and loop closure constraints,and iSAM2 incremental optimization is employed to achieve globally consistent mapping.Municipal tunnel tests show that the loop closure error is reduced to O.096 m and the global reprojection error is l.10 pixels,and the structural continuity of the constructed dense 3D map is significantly improved.This method provides a technical solution with centimeter-level accuracy for tunnel structural health monitoring,which is demonstrating strong practical potential for engineering applications.展开更多
Dear Editor,D2This letter presents a node feature similarity preserving graph convolutional framework P G.Graph neural networks(GNNs)have garnered significant attention for their efficacy in learning graph representat...Dear Editor,D2This letter presents a node feature similarity preserving graph convolutional framework P G.Graph neural networks(GNNs)have garnered significant attention for their efficacy in learning graph representations across diverse real-world applications.展开更多
In the Internet-of-Things(IoT)scenarios,Continual Graph Learning(CGL)has become a key technique for capturing the complex relational structures underlying diverse applications including sensor networks,road systems an...In the Internet-of-Things(IoT)scenarios,Continual Graph Learning(CGL)has become a key technique for capturing the complex relational structures underlying diverse applications including sensor networks,road systems and biomedical networks.However,the structural changes in these evolving graphs introduce instability,making catastrophic forgetting a primary challenge for CGL.Experience replay is currently a promising method,as it strikes a balance between new and old knowledge.It also provides CGL models with a human-like memory capability.However,prior work rarely leverages the graph’s intrinsic properties to proactively identify the critical patterns hiding in the evolving graphs.To this end,we propose a unified framework that integrates cohesionsubgraph awareness into existing CGL mechanisms.We propose a novel cohesive structure-aware experience replay framework that leverages intrinsic graph properties,such as κ-core and κ-truss metrics,to guide the selection of representative historical nodes for replay.Unlike conventional replay strategies that rely on random sampling or task-driven node selection,our approach systematically identifies structurally significant nodes that encapsulate the evolving patterns of streaming graphs.By integrating these cohesive subgraph properties into the experience replay process,our method effectively preserves critical historical knowledge while adapting to new graph structures with low computational overhead.The experimental results demonstrate that our method consistently outperforms existing replay strategies in mitigating catastrophic forgetting and maintaining classification performance.On the PubMed dataset,our-core-based replay strategy improves the F1 score by 3.7% compared to random sampling,while reducing training time by up to 85% compared to full retraining.Similarly,on the Cora dataset,our approach achieves a 98.3% F1 score,surpassing baseline methods by 4.5%.展开更多
Temporal alignment of multisensor time series(MTS)is a critical prerequisite for accurate modeling and optimal control in subsequent data-driven applications.Nevertheless,many approaches frequently neglect to consider...Temporal alignment of multisensor time series(MTS)is a critical prerequisite for accurate modeling and optimal control in subsequent data-driven applications.Nevertheless,many approaches frequently neglect to consider the complex interdependencies between different sensors in MTS,and temporal alignment in many methods is typically treated as an isolated task disconnected from the downstream objectives,leading to unsatisfactory performances in follow-up applications.To address these challenges,this paper proposes a novel knowledge graph(KG)-guided iterative-updating graph neural network(GNN)for time-delay estimation(TDE)in MTS.Initially,a domain-specific KG is constructed from domain mechanism knowledge,providing a foundation for GNN's initialization.Next,capitalizing on the inherent structure of the graph topology,a GNN-based TDE method is developed.Then,a customized loss function is constructed,which synthesizes both the performances of downstream tasks and graph-based constraints.Moreover,an innovative algorithm for GNN structure learning and iterative-updating is proposed to renovate the graph structure further.Finally,experimental results across various regression and classification tasks on numerical simulation,public datasets,and the real blast furnace ironmaking dataset demonstrate that the proposed method can achieve accurate temporal alignment of MTS.展开更多
To address the issues of low exploration efficiency and“geometric myopia”caused by the lack of highlevel environmental structure modeling for mobile robots in complex indoor environments,this paper proposes an activ...To address the issues of low exploration efficiency and“geometric myopia”caused by the lack of highlevel environmental structure modeling for mobile robots in complex indoor environments,this paper proposes an active SLAMobject navigationmethod based on Situational Semantic Augmented Graph(SSAG).Unlikemethods that learn policies solely on pixel-level semantic maps or exploit only object-level relations for implicit association,this work elevates local observations online into a room-level topological graph and performs explicit semantic reasoning over unobserved regions.First,an online room segmentation algorithmis employed to transformunstructured sensory data into a structured graph representation that characterizes room-level functional attributes and topological associations.Subsequently,a Graph Attention Network(GAT)is utilized to perform explicit reasoning on the semantic attributes of unobserved regions,providing decision-making priors for long-range exploration.Building upon this,we introduce a Product of Experts(PoE)mechanism within the Proximal Policy Optimization(PPO)framework to deeply fuse semantic reasoning heatmaps with geometric hard constraints.This integration optimizes the target selection strategy,generating long-term navigation goals with superior semantic consistency and physical reachability.Experimental results on the Habitat simulator and Gibson dataset demonstrate that the proposed SSAG achieves a Success weighted by Path Length(SPL)of 0.340,outperforming SemExp and SemGO by 15.3%and 4.9%,respectively,with a total success rate of 68.4%.Notably,for object search tasks with strong spatial correlations(e.g.,“bed”and“toilet”),the success rates reach 73.2%and 72.5%,representing a performance gain of over 20%compared to baseline methods.These results validate the effectiveness of room-level semantic reasoning for object navigation and demonstrate the capability of the proposed method to achieve efficient autonomous navigation in unknown,complex scenarios.展开更多
A substantial amount hazardous chemical accident(HCA)data have been accumulated in the form of unstructured textual data,making systematic analysis and utilization challenging.More importantly,manually identifying and...A substantial amount hazardous chemical accident(HCA)data have been accumulated in the form of unstructured textual data,making systematic analysis and utilization challenging.More importantly,manually identifying and analyzing key information from a considerable quantity of accident data is inefficient and highly susceptible to subjective bias.To efficiently unlock the value of HCA investigation reports and uncover underlying accident patterns,a semi-automated method for knowledge graph(KG)construction has been developed to model the HCA data.First,an ontology that accurately expresses key factors of HCAs is established.Second,an automated method is developed for the identification,standardization,and enhancement of accident factors,which combines deep learning(DL)and natural language processing(NLP)techniques.Specifically,the deep neural network model,named interaction region and type information(IRTI)is proposed to extract accident factors and their relationships from lengthy HCA data with complex overlapping issues.Non-standard accident factors are standardized using ChatGPT-4 in combination with the proposed text clustering model,named contrastive learningbased short text clustering(CLSTC).The processed accident factors are used to construct the hazardous chemical accident knowledge graph(HCAKG).Finally,the risk factors in the HCAKG are statistically analyzed,and their internal topological relationships are explored to facilitate quantitative analysis.Data from HCA investigation reports are used to demonstrate the effectiveness of this method.The result shows that it improves the accuracy and efficiency of accident data analysis,promoting better risk assessment and management strategies.展开更多
Chain graphs are{2K2,C3,C5}-free graphs.Balaban index and sum-Balaban index are two important topological indices.In this paper,we concentrate on the subclass of bicyclic connected chain graphs,identifying th...Chain graphs are{2K2,C3,C5}-free graphs.Balaban index and sum-Balaban index are two important topological indices.In this paper,we concentrate on the subclass of bicyclic connected chain graphs,identifying the extremal graphs that exhibit the minimum or maximum Balaban index and sum-Balaban index within this class.Moreover,we provide a systematic ordering of all bicyclic connected chain graphs according to the magnitude of their Balaban index and sum-Balaban index.展开更多
The rapid integration of Internet of Things(IoT)devices and distributed energy resources into smart grids has improved monitoring,control,and energy efficiency.However,it also exposes the grid to cyberattacks and priv...The rapid integration of Internet of Things(IoT)devices and distributed energy resources into smart grids has improved monitoring,control,and energy efficiency.However,it also exposes the grid to cyberattacks and privacy risks,as increased connectivity and data exchange can significantly disrupt energy management and system stability.Studies focused on centralized cybersecurity mechanisms that lacked scalability and did not emphasize the inherent graph structure of power networks.This study proposes a privacy-preserving and cyber-resilient energy-optimization framework,FedGNN,for IoT-enabled smart grids that jointly integrates federated learning,graph neural network-based trust inference,and trust-aware energy dispatch.The framework dynamically learns node-level trust scores from multifeature measurements,including load,voltage,frequency,renewable generation,and battery storage,and incorporates them into real-time energy optimization.Results demonstrate that the proposed approach improves system resilience up to 12%,mitigates the impact of compromised nodes,and maintains operational reliability,while preserving the privacy of distributed data.A comparative analysis with baseline methods shows the proposed framework's superior performance in energy deviation,resilience,and trust-aware decision-making.The results highlight the potential of integrating AI-driven trust mechanisms with federated learning for secure and efficient energy management in future IoT-enabled smart grids.展开更多
The vertex-degree function index of a graph G is defined as Hf(G)=∑x∈V(G)f(dG(x)),where dG(x)denotes the degree of vertex x in G and f(x)is a real-valued function.In this work,we determine the extremal v...The vertex-degree function index of a graph G is defined as Hf(G)=∑x∈V(G)f(dG(x)),where dG(x)denotes the degree of vertex x in G and f(x)is a real-valued function.In this work,we determine the extremal values of the vertex-degree function index of unicyclic graphs with fixed girth or with fixed diameter when f(x)is strictly convex(resp.,strictly concave).Moreover,we apply the results directly to some famous topological indices which belong to the family of vertex-degree function indices,such as the first and second multiplicative Zagreb indices,zeroth-order general Randic index,sum lordeg index,variable sum exdeg index.展开更多
基金supported by the National Key Research and Development Program of China(2023YFF0612900,2023YFF0612902)the Natural Science Foundation of Beijing,China(4254086)+3 种基金the National Natural Science Foundation of China(62472032)the Open Project Funding of Key Laboratory of Mobile Application Innovation and Governance Technology,Ministry of Industry and Information Technology(2023IFS080601-K)the Beijing Institute of Technology Research Fund Program for Young Scholarsthe Young Elite Scientists Sponsorship Program by CAST(2023QNRC001)。
摘要Dear Editor,This letter addresses the critical challenge of preserving privacy in graph learning without compromising on data utility.Differential privacy(DP)is emerging as an effective method for privacy-preserving graph learning.However,its application often diminishes data utility,especially for nodes with fewer neighbors in graph neural networks(GNNs).
摘要Dear Editor,This letter presents a novel graph neural network, namely modularized graph convolution network(MGCN), to address the underexplored issue in graph convolution networks(GCNs), wherein the weights for neighbor aggregation are fixed, leading to the limited capability of capturing diverse relationships among nodes for representation learning. Conventional GCNs always learn node representations in the graph according to the weights computed from the graph Laplacian, consequently overlooking the similarity and group cohesiveness of node features.
基金supported by National Natural Science Foundation of China(Grant No.62071098)Sichuan Science and Technology Program(Grants 2022YFG0319,2023YFG0301 and 2023YFG0018)。
摘要In the field of video scene graph generation,spatio-temporal feature extraction and the long-tail effect in relationship classification are core research issues.This paper proposes extracting spatio-temporal features using the global-local Transformer model for video scene graph generation.Methods based on the Transformer architecture and attention mechanism enrich the semantic information of spatio-temporal features in videos,thereby improving the accuracy of relationship classification.In the feature processing module,pose features are introduced to strengthen the semantic representation of objects.In the spatial feature encoding module,a local spatial visibility matrix based on bounding boxes and key points of human pose features is proposed to add the issue of insufficient attention to local details in traditional Transformer encoders.In the temporal feature encoding module,a global random frame extraction strategy is proposed,which considers global temporal features while also taking computational complexity into account.In the relation classification module,to address the uneven distribution of object and relation categories in the Action Genome dataset,a relation classification loss function based on bipartite graph matching and Focal Loss is proposed,which alleviates the long-tail effect in relation classification and improves the accuracy.
基金funded by the Deanship of Graduate Studies and Scientific Research at Jouf University under grant No.(DGSSR-2025-02-01296).
摘要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.
摘要In complex network analysis,node ranking is vital for propagation prediction,structural optimization,and intervention strategy design,yet existing methods often fail to effectively integrate community information in dynamic settings.To address this,this paper proposes a node ranking method that combines graph attention mechanisms with contrastive learning.Community detection is employed to extract node-level community features,and a joint embedding module is designed to fuse global and local structures,thereby incorporating community information into node representations.Based on this,a multi-layer graph attention network adaptively learns node and neighborhood features,while contrastive learning mitigates interference from dynamic evolution and strengthens the model's ability to capture multi-scale structural differences.Experiments on multiple dynamic network datasets show that the proposed method significantly outperforms existing approaches in ranking accuracy,particularly in networks with higher average degrees and clearer community structures.These results validate the effectiveness of the method in enhancing feature representation and modeling multi-scale dynamic node influence.
基金the Media Convergence Project of Yunnan Provincial Key Laboratory(No.220235205)。
摘要Few-shot knowledge graph completion refers to inferring missing entity using limited instances.A key challenge lies in entity representation,which is complicated by diverse neighbor attributes.Although the entity's neighborhood topology holds potential to address this,its significance is overlooked in current research.In this paper,we propose a structure-aware graph attention network for few-shot knowledge graph completion.Firstly,to enhance entity representations,we design a structure-aware graph attention encoder to capture the graph's structural features of nodes,generating embedding for entity pairs.Secondly,a semantic prototype matching network is employed to compute the prediction score.Experiments on the NELL-One and Wiki-One datasets show that our proposed model outperforms the best baseline models by 0.021,0.026,0.039,0.032 and 0.016,0.064,0.043,0.040 in terms of MRR,Hits@10,Hits@5,and Hits@1 metrics,respectively.This demonstrates that our model can effectively leverage neighborhood topological information to improve the accuracy of knowledge completion,and achieve a better generalization.
摘要Transformers have been widely applied to hyperspectral image classification,leveraging their self-attention mechanism for powerful global modelling.However,two key challenges remain as follows:excessive memory and computational costs from calculating correlations between all tokens(especially as image size or spectral bands increase)and limited ability to model local boundary information due to lacking explicit enhancement mechanisms.This paper proposes a novel method,bridge transformer network fused with deep graph convolution(BTDGC),to address these issues.The framework includes three components as follows:a double random masking mechanism(DRMM)that forces the model to infer masked features from context during training,a bridge transformer(BT)module with bridge tokens for cross-region feature interaction and a Deep Graph Convolutional Pooling(DGCP)module that preserves spatial topology while aggregating hierarchical information.Experiments on standard hyperspectral datasets show BTDGC outperforms mainstream methods in classification accuracy and robustness,effectively balancing global modelling and local boundary representation.The code is available at http://gffzz188fe103f8f1460aspovbw6oqw59q6nuc.ffgz.tsg.suse.edu.cn/jenny3489/BTDGC.
基金supported in part by the National Nature Science Foundation of China under Grants 62476216 and 62006184in part by the Key Research and Development Program of Shaanxi Province under Grant 2024GX-YBXM-146+1 种基金in part by the Scientific Research ProgramFunded by EducationDepartment of the Shaanxi Provincial Government under Grant 23JP091the Youth Innovation Team of Shaanxi Universities.
摘要Traffic flow prediction is of great importance in traffic planning,road resource management,and congestion mitigation.However,existing prediction have significant limitations in modeling multi-scale spatial-temporal features,particularly in capturing temporal periodicity and spatial dependency in dynamically evolving traffic networks.This paper proposes a novel framework of traffic flow prediction,referred to as Adaptive Graph Fusion Dual-scale Convolutional Network(AGFDCN),which integrates spatial-temporal dynamic graphs with dual-scale convolutional networks.Specifically,we introduce a Dual-Scale Temporal Network,which combines long-and short-term dilated causal convolutions with a temporal decay-aware attention mechanism to efficiently capture traffic patterns across multiple temporal scales.Furthermore,we design a Dynamic Adaptive Graph Module,which models complex spatial dependencies in traffic networks through an adaptive graph fusion mechanism and a dual-path attention-gated module.Finally,the temporal and spatial representations are integrated by employing a gated fusion mechanism,enhancing the overall prediction performance.Experimental results obtained based on three highway datasets(i.e.,PEMS04,PEMS07 and PEMS08)verify that the proposed model outperforms several state-of-the-art baselines in various evaluation metrics.Compared to the spatial-temporal graph model AGCRN with best performance in the baseline models,the proposed model exhibits significant improvements across all datasets:it achieves reduces of MAE by 42.07%and RMSE by 35.43%on PEMS04;MAE by 28.35%and RMSE by 29.28%on PEMS07;and MAE by 30.52%and RMSE by 30.73%on PEMS08,respectively,validating its effectiveness in modeling complex spatial-temporal traffic data and its robustness in handling sudden traffic changes.
基金funded by the National Key R&D Program of China,grant number 2022YFB2602203the Natural Science Basic Research Program of Shaanxi,grant numbers 2025JC-YBMS-699 and 2024JC-YBQN-0495).
摘要Tunnel environments often suffer from GPS denial,uneven illumination,and structural uniformity,which lead to feature degradation,loop closure failure,and long-distance drift in SLAM systems.To solve these problems,this study aims to propose a high-precision SLAM method suitable for tunnel structural health monitoring.Firstly,an ABA-CLAHE image enhancement algorithm is proposed,which adopts cascaded processing of nonlinear brightness adjustment in HSV space and CLAHE local contrast optimization to improve low-light image quality and enhance feature stability.Then,SURF feature matching combined with the RANSAC algorithm is used to ensure feature matching accuracy.Finally,a factor graph model is constructed by integrating IMU pre-integration,laser odometry,visual odometry,and loop closure constraints,and iSAM2 incremental optimization is employed to achieve globally consistent mapping.Municipal tunnel tests show that the loop closure error is reduced to O.096 m and the global reprojection error is l.10 pixels,and the structural continuity of the constructed dense 3D map is significantly improved.This method provides a technical solution with centimeter-level accuracy for tunnel structural health monitoring,which is demonstrating strong practical potential for engineering applications.
基金supported by the National Natural Science Foundation of China(62402399)the New Chongqing Youth Innovation Talent Project(CSTB2024NSCQ-QCXMX0035)。
摘要Dear Editor,D2This letter presents a node feature similarity preserving graph convolutional framework P G.Graph neural networks(GNNs)have garnered significant attention for their efficacy in learning graph representations across diverse real-world applications.
基金supported in part by the Young Scientists Fund of the Natural Science Foundation of Shandong Province(ZR2022QF134).
摘要In the Internet-of-Things(IoT)scenarios,Continual Graph Learning(CGL)has become a key technique for capturing the complex relational structures underlying diverse applications including sensor networks,road systems and biomedical networks.However,the structural changes in these evolving graphs introduce instability,making catastrophic forgetting a primary challenge for CGL.Experience replay is currently a promising method,as it strikes a balance between new and old knowledge.It also provides CGL models with a human-like memory capability.However,prior work rarely leverages the graph’s intrinsic properties to proactively identify the critical patterns hiding in the evolving graphs.To this end,we propose a unified framework that integrates cohesionsubgraph awareness into existing CGL mechanisms.We propose a novel cohesive structure-aware experience replay framework that leverages intrinsic graph properties,such as κ-core and κ-truss metrics,to guide the selection of representative historical nodes for replay.Unlike conventional replay strategies that rely on random sampling or task-driven node selection,our approach systematically identifies structurally significant nodes that encapsulate the evolving patterns of streaming graphs.By integrating these cohesive subgraph properties into the experience replay process,our method effectively preserves critical historical knowledge while adapting to new graph structures with low computational overhead.The experimental results demonstrate that our method consistently outperforms existing replay strategies in mitigating catastrophic forgetting and maintaining classification performance.On the PubMed dataset,our-core-based replay strategy improves the F1 score by 3.7% compared to random sampling,while reducing training time by up to 85% compared to full retraining.Similarly,on the Cora dataset,our approach achieves a 98.3% F1 score,surpassing baseline methods by 4.5%.
基金supported by the Young Scientists Fund of the National Natural Science Foundation of China(62303491)the Major Program of Xiangjiang Laboratory(22XJ01005)+1 种基金the Science and Technology Innovation Program of Hunan Province(2024RC1007)the Natural Science Foundation of Hunan Province(2025JJ10007)。
摘要Temporal alignment of multisensor time series(MTS)is a critical prerequisite for accurate modeling and optimal control in subsequent data-driven applications.Nevertheless,many approaches frequently neglect to consider the complex interdependencies between different sensors in MTS,and temporal alignment in many methods is typically treated as an isolated task disconnected from the downstream objectives,leading to unsatisfactory performances in follow-up applications.To address these challenges,this paper proposes a novel knowledge graph(KG)-guided iterative-updating graph neural network(GNN)for time-delay estimation(TDE)in MTS.Initially,a domain-specific KG is constructed from domain mechanism knowledge,providing a foundation for GNN's initialization.Next,capitalizing on the inherent structure of the graph topology,a GNN-based TDE method is developed.Then,a customized loss function is constructed,which synthesizes both the performances of downstream tasks and graph-based constraints.Moreover,an innovative algorithm for GNN structure learning and iterative-updating is proposed to renovate the graph structure further.Finally,experimental results across various regression and classification tasks on numerical simulation,public datasets,and the real blast furnace ironmaking dataset demonstrate that the proposed method can achieve accurate temporal alignment of MTS.
基金the Hubei Province Key Research and Development Special Project of Science and Technology Innovation Plan(No.2023BAB087)the Wuhan Key Research and Development Projects(No.2023010402010614)+2 种基金the open competition project for selecting the best candidates,Wuhan East Lake High-Tech Development Zone(No.2024KJB328)the Hubei Provincial Natural Science Foundation Guiding Program Projects[No.2024AFC033]the the Fund for Research Platform of South-Central Minzu University(No.PTZ25003).
摘要To address the issues of low exploration efficiency and“geometric myopia”caused by the lack of highlevel environmental structure modeling for mobile robots in complex indoor environments,this paper proposes an active SLAMobject navigationmethod based on Situational Semantic Augmented Graph(SSAG).Unlikemethods that learn policies solely on pixel-level semantic maps or exploit only object-level relations for implicit association,this work elevates local observations online into a room-level topological graph and performs explicit semantic reasoning over unobserved regions.First,an online room segmentation algorithmis employed to transformunstructured sensory data into a structured graph representation that characterizes room-level functional attributes and topological associations.Subsequently,a Graph Attention Network(GAT)is utilized to perform explicit reasoning on the semantic attributes of unobserved regions,providing decision-making priors for long-range exploration.Building upon this,we introduce a Product of Experts(PoE)mechanism within the Proximal Policy Optimization(PPO)framework to deeply fuse semantic reasoning heatmaps with geometric hard constraints.This integration optimizes the target selection strategy,generating long-term navigation goals with superior semantic consistency and physical reachability.Experimental results on the Habitat simulator and Gibson dataset demonstrate that the proposed SSAG achieves a Success weighted by Path Length(SPL)of 0.340,outperforming SemExp and SemGO by 15.3%and 4.9%,respectively,with a total success rate of 68.4%.Notably,for object search tasks with strong spatial correlations(e.g.,“bed”and“toilet”),the success rates reach 73.2%and 72.5%,representing a performance gain of over 20%compared to baseline methods.These results validate the effectiveness of room-level semantic reasoning for object navigation and demonstrate the capability of the proposed method to achieve efficient autonomous navigation in unknown,complex scenarios.
基金supported by the Key Research and Development Program of Xinjiang Uygur Autonomous Region(2022B03004-3)the National Natural Science Foundation of China(62366052)+1 种基金the Natural Science Foundation of Xinjiang Uygur Autonomous Region(2022D01C427,2022D01C429)the Research Project of Huairou Laboratory(YZD2024025A)。
摘要A substantial amount hazardous chemical accident(HCA)data have been accumulated in the form of unstructured textual data,making systematic analysis and utilization challenging.More importantly,manually identifying and analyzing key information from a considerable quantity of accident data is inefficient and highly susceptible to subjective bias.To efficiently unlock the value of HCA investigation reports and uncover underlying accident patterns,a semi-automated method for knowledge graph(KG)construction has been developed to model the HCA data.First,an ontology that accurately expresses key factors of HCAs is established.Second,an automated method is developed for the identification,standardization,and enhancement of accident factors,which combines deep learning(DL)and natural language processing(NLP)techniques.Specifically,the deep neural network model,named interaction region and type information(IRTI)is proposed to extract accident factors and their relationships from lengthy HCA data with complex overlapping issues.Non-standard accident factors are standardized using ChatGPT-4 in combination with the proposed text clustering model,named contrastive learningbased short text clustering(CLSTC).The processed accident factors are used to construct the hazardous chemical accident knowledge graph(HCAKG).Finally,the risk factors in the HCAKG are statistically analyzed,and their internal topological relationships are explored to facilitate quantitative analysis.Data from HCA investigation reports are used to demonstrate the effectiveness of this method.The result shows that it improves the accuracy and efficiency of accident data analysis,promoting better risk assessment and management strategies.
摘要Chain graphs are{2K2,C3,C5}-free graphs.Balaban index and sum-Balaban index are two important topological indices.In this paper,we concentrate on the subclass of bicyclic connected chain graphs,identifying the extremal graphs that exhibit the minimum or maximum Balaban index and sum-Balaban index within this class.Moreover,we provide a systematic ordering of all bicyclic connected chain graphs according to the magnitude of their Balaban index and sum-Balaban index.
基金supported by the Deanship of Research and Graduate Studies,King Khalid University,for funding this work through a large research project under grant number(RGP2/603/45)Princess Nourah bint Abdulrahman University,Riyadh,Saudi Arabia,through the Researchers Supporting Project number(PNURSP2026R510).
摘要The rapid integration of Internet of Things(IoT)devices and distributed energy resources into smart grids has improved monitoring,control,and energy efficiency.However,it also exposes the grid to cyberattacks and privacy risks,as increased connectivity and data exchange can significantly disrupt energy management and system stability.Studies focused on centralized cybersecurity mechanisms that lacked scalability and did not emphasize the inherent graph structure of power networks.This study proposes a privacy-preserving and cyber-resilient energy-optimization framework,FedGNN,for IoT-enabled smart grids that jointly integrates federated learning,graph neural network-based trust inference,and trust-aware energy dispatch.The framework dynamically learns node-level trust scores from multifeature measurements,including load,voltage,frequency,renewable generation,and battery storage,and incorporates them into real-time energy optimization.Results demonstrate that the proposed approach improves system resilience up to 12%,mitigates the impact of compromised nodes,and maintains operational reliability,while preserving the privacy of distributed data.A comparative analysis with baseline methods shows the proposed framework's superior performance in energy deviation,resilience,and trust-aware decision-making.The results highlight the potential of integrating AI-driven trust mechanisms with federated learning for secure and efficient energy management in future IoT-enabled smart grids.
基金Supported by the Natural Science Foundation of Shanxi Province(Grant No.202303021211154)。
摘要The vertex-degree function index of a graph G is defined as Hf(G)=∑x∈V(G)f(dG(x)),where dG(x)denotes the degree of vertex x in G and f(x)is a real-valued function.In this work,we determine the extremal values of the vertex-degree function index of unicyclic graphs with fixed girth or with fixed diameter when f(x)is strictly convex(resp.,strictly concave).Moreover,we apply the results directly to some famous topological indices which belong to the family of vertex-degree function indices,such as the first and second multiplicative Zagreb indices,zeroth-order general Randic index,sum lordeg index,variable sum exdeg index.