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基于图卷积神经网络的三维点云分割算法Graph⁃PointNet 被引量:5
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作者 陈苏婷 陈怀新 张闯 《现代电子技术》 2022年第6期87-92,共6页
三维点云无序不规则的特性使得传统的卷积神经网络无法直接应用,且大多数点云深度学习模型往往忽略大量的空间信息。为便于捕获空间点邻域信息,获得更好的点云分析性能以用于点云语义分割,文中提出Graph⁃PointNet点云深度学习模型。Grap... 三维点云无序不规则的特性使得传统的卷积神经网络无法直接应用,且大多数点云深度学习模型往往忽略大量的空间信息。为便于捕获空间点邻域信息,获得更好的点云分析性能以用于点云语义分割,文中提出Graph⁃PointNet点云深度学习模型。Graph⁃PointNet在经典点云模型PointNet的基础上,结合二维图像中聚类思想,设计了图卷积特征提取模块取代多层感知器嵌入PointNet中。图卷积特征提取模块首先通过K近邻算法搜寻相邻特征点组成图结构,接着将多组图结构送入图卷积神经网络提取局部特征用于分割。同时文中设计一种新型点云采样方法多邻域采样,多邻域采样通过设置点云间夹角阈值,将点云区分为特征区域和非特征区域,特征区域用于提取特征,非特征区域用于消除噪声。对室内场景S3DIS、室外场景Semantic3D数据集进行实验,得到二者整体精度分别达到89.33%和89.78%,平均交并比达到64.62%,61.47%,均达到最佳效果。最后,进行消融实验,进一步证明了文中所提出的多邻域采样和图卷积特征提取模块对提高点云语义分割的有效性。 展开更多
关键词 三维点云分割 图卷积神经网络 graph⁃pointnet 语义分割 深度学习 多邻域采样 特征提取
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基于PointNet++网络的3D点云数据语义分割与无序抓取系统
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作者 向艳芳 龙罡 张家臣 《机电工程》 北大核心 2025年第1期146-152,184,共8页
针对复杂场景下分拣工件摆放随意、堆叠杂乱,导致机器人抓取困难的问题,设计了一种基于PointNet++网络的3D点云数据语义分割与无序抓取系统。首先,采用归一化算法对采集到的场云数据进行了预处理,解决了数据的一致性和可比性问题;然后,... 针对复杂场景下分拣工件摆放随意、堆叠杂乱,导致机器人抓取困难的问题,设计了一种基于PointNet++网络的3D点云数据语义分割与无序抓取系统。首先,采用归一化算法对采集到的场云数据进行了预处理,解决了数据的一致性和可比性问题;然后,调整了传统的PointNet++模型参数,优化了提取特征的深度与广度;设计了多尺度分割(MSG)模块,通过PointNet++特征提取和分割点云特征传递,对不同尺度下点云数据的上下文信息进行了整合,提升了PointNet++模型运行效率,增强了模型对工件的分割能力;最后,研究了不同算法在散堆工件数据集上的网络训练结果,设计了基于RGB-D深度相机的机器人分拣实验,对改进策略进行了性能分析。研究结果表明:采用改进的PointNet++网络对散堆工件进行检测,其准确率可达97.3%,运算的时间为2 s以内,定位的误差为3 mm以内。该分割方法在识别精度和分拣效率方面均表现优异,能够有效辅助机器人进行实时工件分拣操作。 展开更多
关键词 散堆工件分拣 pointnet++ 特征提取 多尺度分割模块 深度相机 识别精度 分拣效率
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位置自适应卷积PointNet++的点云数据分类方法
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作者 闫晓奇 彭逸清 任小玲 《计算机与现代化》 2025年第1期44-49,共6页
针对复杂场景中点云数据分类精度低问题,提出一种基于位置自适应卷积的PointNet++深度神经网络模型。由于位置自适应卷积具有较强捕捉细粒度局部特征能力,能充分获取三维点云的空间变化和几何结构特征信息,故本文在PointNet++基础上,首... 针对复杂场景中点云数据分类精度低问题,提出一种基于位置自适应卷积的PointNet++深度神经网络模型。由于位置自适应卷积具有较强捕捉细粒度局部特征能力,能充分获取三维点云的空间变化和几何结构特征信息,故本文在PointNet++基础上,首先通过最远点采样获取关键点,其次根据关键点使用K最近邻方法(KNN)实现分组,然后由位置自适应卷积代替原方法中的MLP提取每组的局部特征,最终完成点云分类。在2个公开的点云数据集S3DIS、Semantic3D上对本文方法进行多次对比实验,实验结果表明,本文方法在室内数据集S3DIS上的总体精度和mIoU较PointNet++网络分别提高约2.7个百分点和3.2个百分点,在室外数据集Semantic3D上的总体精度和mIoU PointNet++分别高出约2.5个百分点和2.1个百分点。 展开更多
关键词 点云分类 位置自适应卷积 pointnet++ 深度学习 局部特征
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基于注意力权重PointNet++的电力走廊点云语义分割研究
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作者 鲍万轲 姜媛媛 《东北电力技术》 2025年第1期30-34,52,共6页
传统的电力走廊点云数据的分割会出现精度低、数据局部特征捕获存在局限性等问题,为此提出了一种基于注意力权重的PointNet++网络场景分割模型。将深度学习中的PointNet++算法用于电力走廊场景分割中,再引入了空间注意力机制,帮助模型... 传统的电力走廊点云数据的分割会出现精度低、数据局部特征捕获存在局限性等问题,为此提出了一种基于注意力权重的PointNet++网络场景分割模型。将深度学习中的PointNet++算法用于电力走廊场景分割中,再引入了空间注意力机制,帮助模型更有效地关注重要的空间区域。为此采用自制的数据集,并基于PointNet++网络模型的经典结构,在每个点集抽取(set abstraction,SA)模块中的多层感知机(multi layer perceptron,MLP)加入倒置瓶颈设计,提高对点云数据的处理效率和准确性。研究结果表明,与传统的PointNet++网络相比,改进的PointNet++网络平均交并比(mean intersection over union,mIoU)高出6.3%,加入空间注意力机制的改进模型在自制数据集上表现出更好的分割效果,尤其是在边界划分方面提升明显,验证了该方法在点云语义分割上的有效性。 展开更多
关键词 点云语义分割 输电通道 pointnet++ 注意力机制
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DIGNN-A:Real-Time Network Intrusion Detection with Integrated Neural Networks Based on Dynamic Graph
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作者 Jizhao Liu Minghao Guo 《Computers, Materials & Continua》 SCIE EI 2025年第1期817-842,共26页
The increasing popularity of the Internet and the widespread use of information technology have led to a rise in the number and sophistication of network attacks and security threats.Intrusion detection systems are cr... The increasing popularity of the Internet and the widespread use of information technology have led to a rise in the number and sophistication of network attacks and security threats.Intrusion detection systems are crucial to network security,playing a pivotal role in safeguarding networks from potential threats.However,in the context of an evolving landscape of sophisticated and elusive attacks,existing intrusion detection methodologies often overlook critical aspects such as changes in network topology over time and interactions between hosts.To address these issues,this paper proposes a real-time network intrusion detection method based on graph neural networks.The proposedmethod leverages the advantages of graph neural networks and employs a straightforward graph construction method to represent network traffic as dynamic graph-structured data.Additionally,a graph convolution operation with a multi-head attention mechanism is utilized to enhance the model’s ability to capture the intricate relationships within the graph structure comprehensively.Furthermore,it uses an integrated graph neural network to address dynamic graphs’structural and topological changes at different time points and the challenges of edge embedding in intrusion detection data.The edge classification problem is effectively transformed into node classification by employing a line graph data representation,which facilitates fine-grained intrusion detection tasks on dynamic graph node feature representations.The efficacy of the proposed method is evaluated using two commonly used intrusion detection datasets,UNSW-NB15 and NF-ToN-IoT-v2,and results are compared with previous studies in this field.The experimental results demonstrate that our proposed method achieves 99.3%and 99.96%accuracy on the two datasets,respectively,and outperforms the benchmark model in several evaluation metrics. 展开更多
关键词 Intrusion detection graph neural networks attention mechanisms line graphs dynamic graph neural networks
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Dynamic Multi-Graph Spatio-Temporal Graph Traffic Flow Prediction in Bangkok:An Application of a Continuous Convolutional Neural Network
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作者 Pongsakon Promsawat Weerapan Sae-dan +2 位作者 Marisa Kaewsuwan Weerawat Sudsutad Aphirak Aphithana 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期579-607,共29页
The ability to accurately predict urban traffic flows is crucial for optimising city operations.Consequently,various methods for forecasting urban traffic have been developed,focusing on analysing historical data to u... The ability to accurately predict urban traffic flows is crucial for optimising city operations.Consequently,various methods for forecasting urban traffic have been developed,focusing on analysing historical data to understand complex mobility patterns.Deep learning techniques,such as graph neural networks(GNNs),are popular for their ability to capture spatio-temporal dependencies.However,these models often become overly complex due to the large number of hyper-parameters involved.In this study,we introduce Dynamic Multi-Graph Spatial-Temporal Graph Neural Ordinary Differential Equation Networks(DMST-GNODE),a framework based on ordinary differential equations(ODEs)that autonomously discovers effective spatial-temporal graph neural network(STGNN)architectures for traffic prediction tasks.The comparative analysis of DMST-GNODE and baseline models indicates that DMST-GNODE model demonstrates superior performance across multiple datasets,consistently achieving the lowest Root Mean Square Error(RMSE)and Mean Absolute Error(MAE)values,alongside the highest accuracy.On the BKK(Bangkok)dataset,it outperformed other models with an RMSE of 3.3165 and an accuracy of 0.9367 for a 20-min interval,maintaining this trend across 40 and 60 min.Similarly,on the PeMS08 dataset,DMST-GNODE achieved the best performance with an RMSE of 19.4863 and an accuracy of 0.9377 at 20 min,demonstrating its effectiveness over longer periods.The Los_Loop dataset results further emphasise this model’s advantage,with an RMSE of 3.3422 and an accuracy of 0.7643 at 20 min,consistently maintaining superiority across all time intervals.These numerical highlights indicate that DMST-GNODE not only outperforms baseline models but also achieves higher accuracy and lower errors across different time intervals and datasets. 展开更多
关键词 graph neural networks convolutional neural network deep learning dynamic multi-graph SPATIO-TEMPORAL
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基于PointNet的钢板毛坯垛点云分割
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作者 林振杨 《机电工程技术》 2025年第1期152-156,共5页
钢板毛坯垛拆垛工序中,钢板毛坯分层厚度的估计是推钢机准确且安全执行推钢动作的关键;当前不少企业此道生产工序仍主要靠操作员人工观察的方式估算钢板厚度及与传送辊道的相对高度,其估算不准易导致碰撞,造成输送设备损坏生产中断。提... 钢板毛坯垛拆垛工序中,钢板毛坯分层厚度的估计是推钢机准确且安全执行推钢动作的关键;当前不少企业此道生产工序仍主要靠操作员人工观察的方式估算钢板厚度及与传送辊道的相对高度,其估算不准易导致碰撞,造成输送设备损坏生产中断。提出一种钢板毛坯垛智能分层方法,该方法结合现场工况环境采用激光雷达,对钢板毛坯垛进行三维点云成像,然后对采集的点云数据,用PointNet神经网络框架进行特征识别、分层分割与提取,最后对分割的不同层根据标定值,换算成真实厚度。根据现场实验结果表明,PointNet对钢板毛坯垛分割的识别率达到了87.4%,厚度估算误差低于1.2cm,根据钢厂钢板毛坯规格表(3种规格150、160、180cm)可以准确估计出钢板毛坯厚度的规格,识别速度15帧/s,满足现场工况要求。 展开更多
关键词 钢板毛坯垛 点云分割 特征识别 pointnet
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The Generalized Burning Number of Gear Graph and Sun Graph
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作者 Jiaqing Wu Yinkui Li 《Journal of Applied Mathematics and Physics》 2025年第1期157-165,共9页
Graph burning is a model for describing the spread of influence in social networks and the generalized burning number br(G)of graph Gis a parameter to measure the speed of information spread on network G. In this pape... Graph burning is a model for describing the spread of influence in social networks and the generalized burning number br(G)of graph Gis a parameter to measure the speed of information spread on network G. In this paper, we determined the generalized burning number of gear graph, which is useful model of social network. We also provided properties of the generalized burning number of sun graphs, including characterizations and bounds. 展开更多
关键词 Burning Number Generalized Burning Number Gear graph Sun graph
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Occluded Gait Emotion Recognition Based on Multi-Scale Suppression Graph Convolutional Network
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作者 Yuxiang Zou Ning He +2 位作者 Jiwu Sun Xunrui Huang Wenhua Wang 《Computers, Materials & Continua》 SCIE EI 2025年第1期1255-1276,共22页
In recent years,gait-based emotion recognition has been widely applied in the field of computer vision.However,existing gait emotion recognition methods typically rely on complete human skeleton data,and their accurac... In recent years,gait-based emotion recognition has been widely applied in the field of computer vision.However,existing gait emotion recognition methods typically rely on complete human skeleton data,and their accuracy significantly declines when the data is occluded.To enhance the accuracy of gait emotion recognition under occlusion,this paper proposes a Multi-scale Suppression Graph ConvolutionalNetwork(MS-GCN).TheMS-GCN consists of three main components:Joint Interpolation Module(JI Moudle),Multi-scale Temporal Convolution Network(MS-TCN),and Suppression Graph Convolutional Network(SGCN).The JI Module completes the spatially occluded skeletal joints using the(K-Nearest Neighbors)KNN interpolation method.The MS-TCN employs convolutional kernels of various sizes to comprehensively capture the emotional information embedded in the gait,compensating for the temporal occlusion of gait information.The SGCN extracts more non-prominent human gait features by suppressing the extraction of key body part features,thereby reducing the negative impact of occlusion on emotion recognition results.The proposed method is evaluated on two comprehensive datasets:Emotion-Gait,containing 4227 real gaits from sources like BML,ICT-Pollick,and ELMD,and 1000 synthetic gaits generated using STEP-Gen technology,and ELMB,consisting of 3924 gaits,with 1835 labeled with emotions such as“Happy,”“Sad,”“Angry,”and“Neutral.”On the standard datasets Emotion-Gait and ELMB,the proposed method achieved accuracies of 0.900 and 0.896,respectively,attaining performance comparable to other state-ofthe-artmethods.Furthermore,on occlusion datasets,the proposedmethod significantly mitigates the performance degradation caused by occlusion compared to other methods,the accuracy is significantly higher than that of other methods. 展开更多
关键词 KNN interpolation multi-scale temporal convolution suppression graph convolutional network gait emotion recognition human skeleton
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Note on “Sharp Isolated Toughness Bound for Fractional ( k,m )-Deleted Graphs”
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作者 Wei Gao 《Journal of Applied Mathematics and Physics》 2025年第2期365-380,共16页
As an appendix of [Gao et al. Sharp isolated toughness bound for fractional (k,m)-deleted graphs, Acta Mathematicae Applicatae Sinica, English Series, 2025, 41(1): 252-269], the detailed proof of Theorem 4.1 in this w... As an appendix of [Gao et al. Sharp isolated toughness bound for fractional (k,m)-deleted graphs, Acta Mathematicae Applicatae Sinica, English Series, 2025, 41(1): 252-269], the detailed proof of Theorem 4.1 in this work is presented. 展开更多
关键词 graph Isolated Toughness Variant Fractional -Deleted graph
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The Design and Practice of an Enhanced Search for Maritime Transportation Knowledge Graph Based on Semi-Schema Constraints
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作者 Yiwen Gao Shaohan Wang +1 位作者 Feiyang Ren Xinbo Wang 《Journal of Computer and Communications》 2025年第2期94-125,共32页
With the continuous development of artificial intelligence and natural language processing technologies, traditional retrieval-augmented generation (RAG) techniques face numerous challenges in document answer precisio... With the continuous development of artificial intelligence and natural language processing technologies, traditional retrieval-augmented generation (RAG) techniques face numerous challenges in document answer precision and similarity measurement. This study, set against the backdrop of the shipping industry, combines top-down and bottom-up schema design strategies to achieve precise and flexible knowledge representation. The research adopts a semi-structured approach, innovatively constructing an adaptive schema generation mechanism based on reinforcement learning, which models the knowledge graph construction process as a Markov decision process. This method begins with general concepts, defining foundational industry concepts, and then delves into abstracting core concepts specific to the maritime domain through an adaptive pattern generation mechanism that dynamically adjusts the knowledge structure. Specifically, the study designs a four-layer knowledge construction framework, including the data layer, modeling layer, technology layer, and application layer. It draws on a mutual indexing strategy, integrating large language models and traditional information extraction techniques. By leveraging self-attention mechanisms and graph attention networks, it efficiently extracts semantic relationships. The introduction of logic-form-driven solvers and symbolic decomposition techniques for reasoning significantly enhances the model’s ability to understand complex semantic relationships. Additionally, the use of open information extraction and knowledge alignment techniques further improves the efficiency and accuracy of information retrieval. Experimental results demonstrate that the proposed method not only achieves significant performance improvements in knowledge graph retrieval within the shipping domain but also holds important theoretical innovation and practical application value. 展开更多
关键词 Large Language Models Knowledge graphs graph Attention Networks Maritime Transportation
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A Maritime Document Knowledge Graph Construction Method Based on Conceptual Proximity Relations
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作者 Yiwen Lin Tao Yang +3 位作者 Yuqi Shao Meng Yuan Pinghua Hu Chen Li 《Journal of Computer and Communications》 2025年第2期51-67,共17页
The cost and strict input format requirements of GraphRAG make it less efficient for processing large documents. This paper proposes an alternative approach for constructing a knowledge graph (KG) from a PDF document ... The cost and strict input format requirements of GraphRAG make it less efficient for processing large documents. This paper proposes an alternative approach for constructing a knowledge graph (KG) from a PDF document with a focus on simplicity and cost-effectiveness. The process involves splitting the document into chunks, extracting concepts within each chunk using a large language model (LLM), and building relationships based on the proximity of concepts in the same chunk. Unlike traditional named entity recognition (NER), which identifies entities like “Shanghai”, the proposed method identifies concepts, such as “Convenient transportation in Shanghai” which is found to be more meaningful for KG construction. Each edge in the KG represents a relationship between concepts occurring in the same text chunk. The process is computationally inexpensive, leveraging locally set up tools like Mistral 7B openorca instruct and Ollama for model inference, ensuring the entire graph generation process is cost-free. A method of assigning weights to relationships, grouping similar pairs, and summarizing multiple relationships into a single edge with associated weight and relation details is introduced. Additionally, node degrees and communities are calculated for node sizing and coloring. This approach offers a scalable, cost-effective solution for generating meaningful knowledge graphs from large documents, achieving results comparable to GraphRAG while maintaining accessibility for personal machines. 展开更多
关键词 Knowledge graph Large Language Model Concept Extraction Cost-Effective graph Construction
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Construction of a Maritime Knowledge Graph Using GraphRAG for Entity and Relationship Extraction from Maritime Documents
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作者 Yi Han Tao Yang +2 位作者 Meng Yuan Pinghua Hu Chen Li 《Journal of Computer and Communications》 2025年第2期68-93,共26页
In the international shipping industry, digital intelligence transformation has become essential, with both governments and enterprises actively working to integrate diverse datasets. The domain of maritime and shippi... In the international shipping industry, digital intelligence transformation has become essential, with both governments and enterprises actively working to integrate diverse datasets. The domain of maritime and shipping is characterized by a vast array of document types, filled with complex, large-scale, and often chaotic knowledge and relationships. Effectively managing these documents is crucial for developing a Large Language Model (LLM) in the maritime domain, enabling practitioners to access and leverage valuable information. A Knowledge Graph (KG) offers a state-of-the-art solution for enhancing knowledge retrieval, providing more accurate responses and enabling context-aware reasoning. This paper presents a framework for utilizing maritime and shipping documents to construct a knowledge graph using GraphRAG, a hybrid tool combining graph-based retrieval and generation capabilities. The extraction of entities and relationships from these documents and the KG construction process are detailed. Furthermore, the KG is integrated with an LLM to develop a Q&A system, demonstrating that the system significantly improves answer accuracy compared to traditional LLMs. Additionally, the KG construction process is up to 50% faster than conventional LLM-based approaches, underscoring the efficiency of our method. This study provides a promising approach to digital intelligence in shipping, advancing knowledge accessibility and decision-making. 展开更多
关键词 Maritime Knowledge graph graphRAG Entity and Relationship Extraction Document Management
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k-Product Cordial Labeling of Path Graphs
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作者 Robinson Santrin Sabibha Kruz Jeya Daisy +1 位作者 Pon Jeyanthi Maged Zakaria Youssef 《Open Journal of Discrete Mathematics》 2025年第1期1-29,共29页
In 2012, Ponraj et al. defined a concept of k-product cordial labeling as follows: Let f be a map from V(G)to { 0,1,⋯,k−1 }where k is an integer, 1≤k≤| V(G) |. For each edge uvassign the label f(u)f(v)(modk). f is c... In 2012, Ponraj et al. defined a concept of k-product cordial labeling as follows: Let f be a map from V(G)to { 0,1,⋯,k−1 }where k is an integer, 1≤k≤| V(G) |. For each edge uvassign the label f(u)f(v)(modk). f is called a k-product cordial labeling if | vf(i)−vf(j) |≤1, and | ef(i)−ef(j) |≤1, i,j∈{ 0,1,⋯,k−1 }, where vf(x)and ef(x)denote the number of vertices and edges respectively labeled with x (x=0,1,⋯,k−1). Motivated by this concept, we further studied and established that several families of graphs admit k-product cordial labeling. In this paper, we show that the path graphs Pnadmit k-product cordial labeling. 展开更多
关键词 Cordial Labeling Product Cordial Labeling k-Product Cordial Labeling Path graph
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Aspect-Level Sentiment Analysis of Bi-Graph Convolutional Networks Based on Enhanced Syntactic Structural Information
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作者 Junpeng Hu Yegang Li 《Journal of Computer and Communications》 2025年第1期72-89,共18页
Aspect-oriented sentiment analysis is a meticulous sentiment analysis task that aims to analyse the sentiment polarity of specific aspects. Most of the current research builds graph convolutional networks based on dep... Aspect-oriented sentiment analysis is a meticulous sentiment analysis task that aims to analyse the sentiment polarity of specific aspects. Most of the current research builds graph convolutional networks based on dependent syntactic trees, which improves the classification performance of the models to some extent. However, the technical limitations of dependent syntactic trees can introduce considerable noise into the model. Meanwhile, it is difficult for a single graph convolutional network to aggregate both semantic and syntactic structural information of nodes, which affects the final sentence classification. To cope with the above problems, this paper proposes a bi-channel graph convolutional network model. The model introduces a phrase structure tree and transforms it into a hierarchical phrase matrix. The adjacency matrix of the dependent syntactic tree and the hierarchical phrase matrix are combined as the initial matrix of the graph convolutional network to enhance the syntactic information. The semantic information feature representations of the sentences are obtained by the graph convolutional network with a multi-head attention mechanism and fused to achieve complementary learning of dual-channel features. Experimental results show that the model performs well and improves the accuracy of sentiment classification on three public benchmark datasets, namely Rest14, Lap14 and Twitter. 展开更多
关键词 Aspect-Level Sentiment Analysis Sentiment Knowledge Multi-Head Attention Mechanism graph Convolutional Networks
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基于PointNet++的颅内动脉瘤3D点云分割
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作者 徐豪豪 涂心兰 +2 位作者 彭执萱 张文林 王家琦 《电脑知识与技术》 2025年第1期33-35,40,共4页
颅内动脉瘤的精准分割在医学影像诊断中具有重要意义。文章提出了一种基于3D点云的先进方法,通过提取动脉瘤特征实现高精度分割。针对传统点云分割方法存在的数据预处理要求高、局部特征捕捉不足以及层间信息流失等问题,文章引入了Point... 颅内动脉瘤的精准分割在医学影像诊断中具有重要意义。文章提出了一种基于3D点云的先进方法,通过提取动脉瘤特征实现高精度分割。针对传统点云分割方法存在的数据预处理要求高、局部特征捕捉不足以及层间信息流失等问题,文章引入了PointNet++网络架构。PointNet++在点云数据的分类和分割任务中展现了卓越性能,其通过对点云中的局部和全局特征进行学习,能够有效处理不规则和无序的数据集。这一特性使其特别适合从CTA和MRA影像中提取颅内动脉瘤的特征。文章采用PointNet++网络对CTA和MRA影像进行预处理,以适应不同医院影像设备的差异,并利用该网络进行分割,精准捕捉颅内动脉瘤的边缘特征,从而实现高精度分割。该方法为颅内动脉瘤的精准分割提供了一种可行的解决方案,有助于提高诊断效率并降低医疗成本。 展开更多
关键词 深度学习 颅内动脉瘤 3D点云 pointnet++ 图像分割
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Gallai-Ramsey numbers for three graphs on at most five vertices
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作者 SU Xue-li LIU Yan 《Applied Mathematics(A Journal of Chinese Universities)》 2025年第1期137-148,共12页
A Gallai k-coloring is a k-edge-coloring of a complete graph in which there are no rainbow triangles.For given graphs G_(1),G_(2),G_(3)and nonnegative integers r,s,t with k=r+s+t,the k-colored Gallai-Ramsey number grk... A Gallai k-coloring is a k-edge-coloring of a complete graph in which there are no rainbow triangles.For given graphs G_(1),G_(2),G_(3)and nonnegative integers r,s,t with k=r+s+t,the k-colored Gallai-Ramsey number grk(K_(3):r·G_(1),s·G_(2),t·G_(3))is the minimum integer n such that every Gallai k-colored Kncontains a monochromatic copy of G_(1)colored by one of the first r colors or a monochromatic copy of G_(2)colored by one of the middle s colors or a monochromatic copy of G_(3)colored by one of the last t colors.In this paper,we determine the value of GallaiRamsey number in the case that G_(1)=B_(3)^(+),G_(2)=S_(3)^(+)and G_(3)=K_(3).Then the Gallai-Ramsey numbers grk(K_(3):B_(3)^(+)),grk(K_(3):S_(3)^(+))and grk(K_(3):K_(3))are obtained,respectively.Furthermore,the Gallai-Ramsey numbers grk(K_(3):r·B_(3)^(+),(k-r)·S_(3)^(+)),grk(K_(3):r·B_(3)^(+),(k-r)·K_(3))and grk(K_(3):s·S_(3)^(+),(k-s)·K_(3))are obtained,respectively. 展开更多
关键词 Gallai coloring rainbow triangle monochromatic graph Gallai-Ramsey number
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Knowledge Graph Construction and Rule Matching Approach for Aerospace Product Manufacturability Assessment
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作者 Ziyan Liu Zujie Zheng +1 位作者 Lebao Wu Zuhua Jiang 《Journal of Harbin Institute of Technology(New Series)》 2025年第1期1-14,共14页
After the design of aerospace products is completed,a manufacturability assessment needs to be conducted based on 3D model's features in terms of modeling quality and process design,otherwise the cost of design ch... After the design of aerospace products is completed,a manufacturability assessment needs to be conducted based on 3D model's features in terms of modeling quality and process design,otherwise the cost of design changes will increase.Due to the poor structure and low reusability of product manufacturing feature information and assessment knowledge in the current aerospace product manufacturability assessment process,it is difficult to realize automated manufacturability assessment.To address these issues,a domain ontology model is established for aerospace product manufacturability assessment in this paper.On this basis,a structured representation method of manufacturability assessment knowledge and a knowledge graph data layer construction method are proposed.Based on the semantic information and association information expressed by the knowledge graph,a rule matching method based on subgraph matching is proposed to improve the precision and recall.Finally,applications and experiments based on the software platform verify the effectiveness of the proposed knowledge graph construction and rule matching method. 展开更多
关键词 knowledge graph aerospace product manufacturability assessment rule matching
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Research on the Construction of“Same Course with Different Structures”Curriculum Resources Based on Knowledge Graphs
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作者 Chunsu Zhang 《Journal of Contemporary Educational Research》 2025年第1期129-134,共6页
This paper explores the construction methods of“Same Course with Different Structures”curriculum resources based on knowledge graphs and their applications in the field of education.By reviewing the theoretical foun... This paper explores the construction methods of“Same Course with Different Structures”curriculum resources based on knowledge graphs and their applications in the field of education.By reviewing the theoretical foundations of knowledge graph technology,the“Same Course with Different Structures”teaching model,and curriculum resource construction,and integrating existing literature,the paper analyzes the methods for constructing curriculum resources using knowledge graphs.The research finds that knowledge graphs can effectively integrate multi-source data,support personalized teaching and precision education,and provide both a scientific foundation and technical support for the development of curriculum resources within the“Same Course with Different Structures”framework. 展开更多
关键词 Knowledge graph Same Course with Different Structures Resource construction
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基于yEd Graph Editor的矿井通风网络图自动绘制方法研究
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作者 王少丰 魏宗康 《能源技术与管理》 2025年第1期155-158,共4页
针对矿井通风系统网络图绘制过程中存在的绘制难度大、工作量繁重、易出错等突出问题,提出了一种基于yEd Graph Editor(yEd)软件的自动化绘制方法。详细分析了基于yEd的自动绘制原理、步骤及优势,并通过实例展示了矿井通风网络图的绘制... 针对矿井通风系统网络图绘制过程中存在的绘制难度大、工作量繁重、易出错等突出问题,提出了一种基于yEd Graph Editor(yEd)软件的自动化绘制方法。详细分析了基于yEd的自动绘制原理、步骤及优势,并通过实例展示了矿井通风网络图的绘制效果。同时,还分析了yEd在绘制矿井通风系统网络图时的局限性,并提出了相应的优化建议。研究结果表明,使用yEd可以显著提高绘制的速度、准确性和可靠性,从而为矿井通风系统的设计和安全管理提供了有力的技术支持。 展开更多
关键词 矿井通风 网络图绘制 自动化 yEd graph Editor
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