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Matching spatial relation graphs using a constrained partial permutation strategy
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作者 徐晓刚 孙正兴 刘文印 《Journal of Southeast University(English Edition)》 EI CAS 2003年第3期236-239,共4页
A constrained partial permutation strategy is proposed for matching spatial relation graph (SRG), which is used in our sketch input and recognition system Smart Sketchpad for representing the spatial relationship amon... A constrained partial permutation strategy is proposed for matching spatial relation graph (SRG), which is used in our sketch input and recognition system Smart Sketchpad for representing the spatial relationship among the components of a graphic object. Using two kinds of matching constraints dynamically generated in the matching process, the proposed approach can prune most improper mappings between SRGs during the matching process. According to our theoretical analysis in this paper, the time complexity of our approach is O(n 2) in the best case, and O(n!) in the worst case, which occurs infrequently. The spatial complexity is always O(n) for all cases. Implemented in Smart Sketchpad, our proposed strategy is of good performance. 展开更多
关键词 spatial relation graph graph matching constrained partial permutation graphics recognition
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INTEGRATED APPROACH TO GENERATION OF PRECEDENCE RELATIONS AND PRECEDENCE GRAPHS FOR ASSEMBLY SEQUENCE PLANNING 被引量:3
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作者 Niu Xinwen Ding Han Xiong YoulunSchool of Mechanical Science and Engineering, Huazhong University of Science and TechnologyWuhan 430074, China 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2002年第3期193-198,共6页
An integrated approach to generation of precedence relations and precedencegraphs for assembly sequence planning is presented, which contains more assembly flexibility. Theapproach involves two stages. Based on the as... An integrated approach to generation of precedence relations and precedencegraphs for assembly sequence planning is presented, which contains more assembly flexibility. Theapproach involves two stages. Based on the assembly model, the components in the assembly can bedivided into partially constrained components and completely con-strained components in the firststage, and then geometric precedence relation for every component is generated automatically.According to the result of the first stage, the second stage determines and constructs allprecedence graphs. The algorithms of these two stages proposed are verified by two assemblyexamples. 展开更多
关键词 Assembly sequence planning Assembly flexibility Precedence relations Precedence graphs
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Chinese satellite frequency and orbit entity relation extraction method based on dynamic integrated learning 被引量:1
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作者 Yuanzhi He Zhiqiang Li Zheng Dou 《Digital Communications and Networks》 2025年第3期787-794,共8页
Given the scarcity of Satellite Frequency and Orbit(SFO)resources,it holds paramount importance to establish a comprehensive knowledge graph of SFO field(SFO-KG)and employ knowledge reasoning technology to automatical... Given the scarcity of Satellite Frequency and Orbit(SFO)resources,it holds paramount importance to establish a comprehensive knowledge graph of SFO field(SFO-KG)and employ knowledge reasoning technology to automatically mine available SFO resources.An essential aspect of constructing SFO-KG is the extraction of Chinese entity relations.Unfortunately,there is currently no publicly available Chinese SFO entity Relation Extraction(RE)dataset.Moreover,publicly available SFO text data contain numerous NA(representing for“No Answer”)relation category sentences that resemble other relation sentences and pose challenges in accurate classification,resulting in low recall and precision for the NA relation category in entity RE.Consequently,this issue adversely affects both the accuracy of constructing the knowledge graph and the efficiency of RE processes.To address these challenges,this paper proposes a method for extracting Chinese SFO text entity relations based on dynamic integrated learning.This method includes the construction of a manually annotated Chinese SFO entity RE dataset and a classifier combining features of SFO resource data.The proposed approach combines integrated learning and pre-training models,specifically utilizing Bidirectional Encoder Representation from Transformers(BERT).In addition,it incorporates one-class classification,attention mechanisms,and dynamic feedback mechanisms to improve the performance of the RE model.Experimental results show that the proposed method outperforms the traditional methods in terms of F1 value when extracting entity relations from both balanced and long-tailed datasets. 展开更多
关键词 Knowledge graph relation extraction One-class classification Satellite frequency and orbit resources BERT
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Multi-View Picture Fuzzy Clustering:A Novel Method for Partitioning Multi-View Relational Data 被引量:1
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作者 Pham Huy Thong Hoang Thi Canh +2 位作者 Luong Thi Hong Lan Nguyen Tuan Huy Nguyen Long Giang 《Computers, Materials & Continua》 2025年第6期5461-5485,共25页
Multi-view clustering is a critical research area in computer science aimed at effectively extracting meaningful patterns from complex,high-dimensional data that single-view methods cannot capture.Traditional fuzzy cl... Multi-view clustering is a critical research area in computer science aimed at effectively extracting meaningful patterns from complex,high-dimensional data that single-view methods cannot capture.Traditional fuzzy clustering techniques,such as Fuzzy C-Means(FCM),face significant challenges in handling uncertainty and the dependencies between different views.To overcome these limitations,we introduce a new multi-view fuzzy clustering approach that integrates picture fuzzy sets with a dual-anchor graph method for multi-view data,aiming to enhance clustering accuracy and robustness,termed Multi-view Picture Fuzzy Clustering(MPFC).In particular,the picture fuzzy set theory extends the capability to represent uncertainty by modeling three membership levels:membership degrees,neutral degrees,and refusal degrees.This allows for a more flexible representation of uncertain and conflicting data than traditional fuzzy models.Meanwhile,dual-anchor graphs exploit the similarity relationships between data points and integrate information across views.This combination improves stability,scalability,and robustness when handling noisy and heterogeneous data.Experimental results on several benchmark datasets demonstrate significant improvements in clustering accuracy and efficiency,outperforming traditional methods.Specifically,the MPFC algorithm demonstrates outstanding clustering performance on a variety of datasets,attaining a Purity(PUR)score of 0.6440 and an Accuracy(ACC)score of 0.6213 for the 3 Sources dataset,underscoring its robustness and efficiency.The proposed approach significantly contributes to fields such as pattern recognition,multi-view relational data analysis,and large-scale clustering problems.Future work will focus on extending the method for semi-supervised multi-view clustering,aiming to enhance adaptability,scalability,and performance in real-world applications. 展开更多
关键词 Multi-view clustering picture fuzzy sets dual anchor graph fuzzy clustering multi-view relational data
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A close look at few-shot real image super-resolution from the distortion relation perspective
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作者 Xin Li Xin Jin +3 位作者 Jun Fu Xiaoyuan Yu Bei Tong Zhibo Chen 《中国科学技术大学学报》 北大核心 2025年第7期2-13,1,I0001,共14页
Collecting amounts of distorted/clean image pairs in the real world is non-trivial,which severely limits the practical application of these supervised learning-based methods to real-world image super-resolution(RealSR... Collecting amounts of distorted/clean image pairs in the real world is non-trivial,which severely limits the practical application of these supervised learning-based methods to real-world image super-resolution(RealSR).Previous works usually address this problem by leveraging unsupervised learning-based technologies to alleviate the dependency on paired training samples.However,these methods typically suffer from unsatisfactory texture synthesis due to the lack of supervision of clean images.To overcome this problem,we are the first to take a close look at the under-explored direction for RealSR,i.e.,few-shot real-world image super-resolution,which aims to tackle the challenging RealSR problem with few-shot distorted/clean image pairs.Under this brand-new scenario,we propose distortion relation guided transfer learning(DRTL)for the few-shot RealSR by transferring the rich restoration knowledge from auxiliary distortions(i.e.,synthetic distortions)to the target RealSR under the guidance of the distortion relation.Concretely,DRTL builds a knowledge graph to capture the distortion relation between auxiliary distortions and target distortion(i.e.,real distortions in RealSR).Based on the distortion relation,DRTL adopts a gradient reweighting strategy to guide the knowledge transfer process between auxiliary distortions and target distortions.In this way,DRTL is able to quickly learn the most relevant knowledge from the synthetic distortions for the target distortion.We instantiate DRTL with two commonly-used transfer learning paradigms,including pretraining and meta-learning pipelines,to realize a distortion relation-aware few-shot RealSR.Extensive experiments on multiple benchmarks and thorough ablation studies demonstrate the effectiveness of our DRTL. 展开更多
关键词 few-shot RealSR distortion relation graph transfer learning
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DMGNN:A Dual Multi-Relational GNN Model for Enhanced Recommendation
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作者 Siyue Li Tian Jin +3 位作者 Erfan Wang Ranting Tao Jiaxin Lu Kai Xi 《Computers, Materials & Continua》 2025年第8期2331-2353,共23页
In the era of exponential growth of digital information,recommender algorithms are vital for helping users navigate vast data to find relevant items.Traditional approaches such as collaborative filtering and contentba... In the era of exponential growth of digital information,recommender algorithms are vital for helping users navigate vast data to find relevant items.Traditional approaches such as collaborative filtering and contentbasedmethods have limitations in capturing complex,multi-faceted relationships in large-scale,sparse datasets.Recent advances in Graph Neural Networks(GNNs)have significantly improved recommendation performance by modeling high-order connection patterns within user-item interaction networks.However,existing GNN-based models like LightGCN and NGCF focus primarily on single-type interactions and often overlook diverse semantic relationships,leading to reduced recommendation diversity and limited generalization.To address these challenges,this paper proposes a dual multi-relational graph neural network recommendation algorithm based on relational interactions.Our approach constructs two complementary graph structures:a User-Item Interaction Graph(UIIG),which explicitly models direct user behaviors such as clicks and purchases,and a Relational Association Graph(RAG),which uncovers latent associations based on user similarities and item attributes.The proposed Dual Multi-relational Graph Neural Network(DMGNN)features two parallel branches that perform multi-layer graph convolutional operations,followed by an adaptive fusion mechanism to effectively integrate information from both graphs.This design enhances the model’s capacity to capture diverse relationship types and complex relational patterns.Extensive experiments conducted on benchmark datasets—including MovieLens-1M,Amazon-Electronics,and Yelp—demonstrate thatDMGNN outperforms state-of-the-art baselines,achieving improvements of up to 12.3%in Precision,9.7%in Recall,and 11.5%in F1 score.Moreover,DMGNN significantly boosts recommendation diversity by 15.2%,balancing accuracy with exploration.These results highlight the effectiveness of leveraging hierarchical multi-relational information,offering a promising solution to the challenges of data sparsity and relation heterogeneity in recommendation systems.Our work advances the theoretical understanding of multi-relational graph modeling and presents practical insights for developing more personalized,diverse,and robust recommender systems. 展开更多
关键词 Recommendation algorithm graph neural network multi-relational graph relational interaction
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Graph Convolutional Networks Embedding Textual Structure Information for Relation Extraction
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作者 Chuyuan Wei Jinzhe Li +2 位作者 Zhiyuan Wang Shanshan Wan Maozu Guo 《Computers, Materials & Continua》 SCIE EI 2024年第5期3299-3314,共16页
Deep neural network-based relational extraction research has made significant progress in recent years,andit provides data support for many natural language processing downstream tasks such as building knowledgegraph,... Deep neural network-based relational extraction research has made significant progress in recent years,andit provides data support for many natural language processing downstream tasks such as building knowledgegraph,sentiment analysis and question-answering systems.However,previous studies ignored much unusedstructural information in sentences that could enhance the performance of the relation extraction task.Moreover,most existing dependency-based models utilize self-attention to distinguish the importance of context,whichhardly deals withmultiple-structure information.To efficiently leverage multiple structure information,this paperproposes a dynamic structure attention mechanism model based on textual structure information,which deeplyintegrates word embedding,named entity recognition labels,part of speech,dependency tree and dependency typeinto a graph convolutional network.Specifically,our model extracts text features of different structures from theinput sentence.Textual Structure information Graph Convolutional Networks employs the dynamic structureattention mechanism to learn multi-structure attention,effectively distinguishing important contextual features invarious structural information.In addition,multi-structure weights are carefully designed as amergingmechanismin the different structure attention to dynamically adjust the final attention.This paper combines these featuresand trains a graph convolutional network for relation extraction.We experiment on supervised relation extractiondatasets including SemEval 2010 Task 8,TACRED,TACREV,and Re-TACED,the result significantly outperformsthe previous. 展开更多
关键词 relation extraction graph convolutional neural networks dependency tree dynamic structure attention
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A Graph with Adaptive AdjacencyMatrix for Relation Extraction
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作者 Run Yang YanpingChen +1 位作者 Jiaxin Yan Yongbin Qin 《Computers, Materials & Continua》 SCIE EI 2024年第9期4129-4147,共19页
The relation is a semantic expression relevant to two named entities in a sentence.Since a sentence usually contains several named entities,it is essential to learn a structured sentence representation that encodes de... The relation is a semantic expression relevant to two named entities in a sentence.Since a sentence usually contains several named entities,it is essential to learn a structured sentence representation that encodes dependency information specific to the two named entities.In related work,graph convolutional neural networks are widely adopted to learn semantic dependencies,where a dependency tree initializes the adjacency matrix.However,this approach has two main issues.First,parsing a sentence heavily relies on external toolkits,which can be errorprone.Second,the dependency tree only encodes the syntactical structure of a sentence,which may not align with the relational semantic expression.In this paper,we propose an automatic graph learningmethod to autonomously learn a sentence’s structural information.Instead of using a fixed adjacency matrix initialized by a dependency tree,we introduce an Adaptive Adjacency Matrix to encode the semantic dependency between tokens.The elements of thismatrix are dynamically learned during the training process and optimized by task-relevant learning objectives,enabling the construction of task-relevant semantic dependencies within a sentence.Our model demonstrates superior performance on the TACRED and SemEval 2010 datasets,surpassing previous works by 1.3%and 0.8%,respectively.These experimental results show that our model excels in the relation extraction task,outperforming prior models. 展开更多
关键词 relation extraction graph convolutional neural network adaptive adjacency matrix
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Local-to-Global Causal Reasoning for Cross-Document Relation Extraction 被引量:1
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作者 Haoran Wu Xiuyi Chen +3 位作者 Zefa Hu Jing Shi Shuang Xu Bo Xu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第7期1608-1621,共14页
Cross-document relation extraction(RE),as an extension of information extraction,requires integrating information from multiple documents retrieved from open domains with a large number of irrelevant or confusing nois... Cross-document relation extraction(RE),as an extension of information extraction,requires integrating information from multiple documents retrieved from open domains with a large number of irrelevant or confusing noisy texts.Previous studies focus on the attention mechanism to construct the connection between different text features through semantic similarity.However,similarity-based methods cannot distinguish valid information from highly similar retrieved documents well.How to design an effective algorithm to implement aggregated reasoning in confusing information with similar features still remains an open issue.To address this problem,we design a novel local-toglobal causal reasoning(LGCR)network for cross-document RE,which enables efficient distinguishing,filtering and global reasoning on complex information from a causal perspective.Specifically,we propose a local causal estimation algorithm to estimate the causal effect,which is the first trial to use the causal reasoning independent of feature similarity to distinguish between confusing and valid information in cross-document RE.Furthermore,based on the causal effect,we propose a causality guided global reasoning algorithm to filter the confusing information and achieve global reasoning.Experimental results under the closed and the open settings of the large-scale dataset Cod RED demonstrate our LGCR network significantly outperforms the state-ofthe-art methods and validate the effectiveness of causal reasoning in confusing information processing. 展开更多
关键词 Causal reasoning cross document graph reasoning relation extraction(RE)
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Exhibition of Monogamy Relations between Entropic Non-contextuality Inequalities
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作者 朱锋 张巍 黄翊东 《Communications in Theoretical Physics》 SCIE CAS CSCD 2017年第6期626-630,共5页
We exhibit the monogamy relation between two entropic non-contextuality inequalities in the scenario where compatible projectors are orthogonal. We show the monogamy relation can be exhibited by decomposing the orthog... We exhibit the monogamy relation between two entropic non-contextuality inequalities in the scenario where compatible projectors are orthogonal. We show the monogamy relation can be exhibited by decomposing the orthogonality graph into perfect induced subgraphs. Then we find two entropic non-contextuality inequalities are monogamous while the KCBS-type non-contextuality inequalities are not if the orthogonality graphs of the observable sets are two odd cycles with two shared vertices. 展开更多
关键词 entropic non-contextuality inequality monogamy relation perfect graph
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Qualia Role-Based Quantity Relation Extraction for Solving Algebra Story Problems
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作者 Bin He Hao Meng +2 位作者 Zhejin Zhang Rui Liu Ting Zhang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第7期403-419,共17页
A qualia role-based entity-dependency graph(EDG)is proposed to represent and extract quantity relations for solving algebra story problems stated in Chinese.Traditional neural solvers use end-to-end models to translat... A qualia role-based entity-dependency graph(EDG)is proposed to represent and extract quantity relations for solving algebra story problems stated in Chinese.Traditional neural solvers use end-to-end models to translate problem texts into math expressions,which lack quantity relation acquisition in sophisticated scenarios.To address the problem,the proposed method leverages EDG to represent quantity relations hidden in qualia roles of math objects.Algorithms were designed for EDG generation and quantity relation extraction for solving algebra story problems.Experimental result shows that the proposedmethod achieved an average accuracy of 82.2%on quantity relation extraction compared to 74.5%of baseline method.Another prompt learning result shows a 5%increase obtained in problem solving by injecting the extracted quantity relations into the baseline neural solvers. 展开更多
关键词 Quantity relation extraction algebra story problem solving qualia role entity dependency graph
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The Ordering of Unicyclic Graphs with Minimal Matching Energies
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作者 DONG Bo LI Huan WANG Ligong 《数学进展》 北大核心 2025年第5期951-972,共22页
The concept of matching energy was proposed by Gutman and Wagner firstly in 2012. Let G be a simple graph of order n and λ1, λ2, . . . , λn be the zeros of its matching polynomial. The matching energy of a graph G ... The concept of matching energy was proposed by Gutman and Wagner firstly in 2012. Let G be a simple graph of order n and λ1, λ2, . . . , λn be the zeros of its matching polynomial. The matching energy of a graph G is defined as ME(G) = Pni=1 |λi|. By the famous Coulson’s formula, matching energies can also be calculated by an improper integral depending on a parameter. A k-claw attaching graph Gu(k) refers to the graph obtained by attaching k pendent edges to the graph G at the vertex u, where u is called the root of Gu(k). In this paper, we use some theories of mathematical analysis to obtain a new technique to compare the matching energies of two k-claw attaching graphs Gu(k) and Hv(k) with the same order, that is, limk→∞[ME(Gu(k)) − ME(Hv(k))] = ME(G − u) − ME(H − v). By the technique, we finally determine unicyclic graphs of order n with the 9th to 13th minimal matching energies for all n ≥ 58. 展开更多
关键词 matching energy unicyclic graph quasi-order relation k-claw attaching graph
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Efficient Parameterization for Knowledge Graph Embedding Using Hierarchical Attention Network
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作者 Zhen-Yu Chen Feng-Chi Liu +2 位作者 Xin Wang Cheng-Hsiung Lee Ching-Sheng Lin 《Computers, Materials & Continua》 2025年第3期4287-4300,共14页
In the domain of knowledge graph embedding,conventional approaches typically transform entities and relations into continuous vector spaces.However,parameter efficiency becomes increasingly crucial when dealing with l... In the domain of knowledge graph embedding,conventional approaches typically transform entities and relations into continuous vector spaces.However,parameter efficiency becomes increasingly crucial when dealing with large-scale knowledge graphs that contain vast numbers of entities and relations.In particular,resource-intensive embeddings often lead to increased computational costs,and may limit scalability and adaptability in practical environ-ments,such as in low-resource settings or real-world applications.This paper explores an approach to knowledge graph representation learning that leverages small,reserved entities and relation sets for parameter-efficient embedding.We introduce a hierarchical attention network designed to refine and maximize the representational quality of embeddings by selectively focusing on these reserved sets,thereby reducing model complexity.Empirical assessments validate that our model achieves high performance on the benchmark dataset with fewer parameters and smaller embedding dimensions.The ablation studies further highlight the impact and contribution of each component in the proposed hierarchical attention structure. 展开更多
关键词 Knowledge graph embedding parameter efficiency representation learning reserved entity and relation sets hierarchical attention network
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基于语义图增强注意力网络的症状属性分类方法
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作者 贾鹤鸣 李伟 +1 位作者 李波 张志东 《计算机应用研究》 北大核心 2026年第1期53-59,共7页
医疗对话中的症状属性分类是实现自动诊断系统的关键任务之一,旨在识别对话文本中描述的症状所对应的属性类别。然而,现有方法在处理长文本对话时普遍存在上下文建模能力不足、语义依赖捕捉不充分等问题,导致整体分类性能受限,尤其在少... 医疗对话中的症状属性分类是实现自动诊断系统的关键任务之一,旨在识别对话文本中描述的症状所对应的属性类别。然而,现有方法在处理长文本对话时普遍存在上下文建模能力不足、语义依赖捕捉不充分等问题,导致整体分类性能受限,尤其在少数类样本上的表现欠佳。针对上述挑战,提出一种基于语义图增强注意力网络的症状属性分类方法。该方法通过构建症状关联的文本分割方法、融合编码策略以及基于依存树的关系图注意力网络,在多个层次上增强模型对症状上下文信息的建模能力。实验结果表明,所提方法在CHIP-MDCFNPC数据集上取得了72.13%的F 1(+1.76%)和77.94%的宏平均F 1值(+1.77%)。所提方法能够显著提升长文本医疗对话中症状属性分类的效果,尤其在少数类样本上的表现更为突出,为构建高效可靠的自动诊断系统提供了有益借鉴。 展开更多
关键词 症状属性分类 文本分割 关系图注意力机制
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融合液态神经网络与多层级图卷积的关系抽取方法
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作者 李子亮 李兴春 《计算机应用研究》 北大核心 2026年第1期69-75,共7页
针对自然语言处理中关系抽取任务在建模长距离依赖与复杂语义理解方面的不足,提出了一种融合液态神经网络与多层级图卷积网络的关系抽取模型BLGAM。该模型首先利用BERT对输入句子进行上下文语义编码,获得初始文本表示;随后通过基于闭式... 针对自然语言处理中关系抽取任务在建模长距离依赖与复杂语义理解方面的不足,提出了一种融合液态神经网络与多层级图卷积网络的关系抽取模型BLGAM。该模型首先利用BERT对输入句子进行上下文语义编码,获得初始文本表示;随后通过基于闭式连续时间解的液态神经网络捕捉动态时序特征,建模长距离依赖信息;同时结合依存句法和实体结构构建多层级图卷积网络,提取局部与全局结构化语义特征;最后采用注意力门控机制对时序特征与结构特征进行加权融合,并通过多层感知机提升实体对关系识别的准确性与鲁棒性。在NYT和WebNLG两个公开数据集上的实验结果表明,该模型的F 1值分别达到92.6%和92.1%,均优于现有主流基线,验证了液态神经网络在长距离依赖建模与动态信息捕捉方面的显著优势,以及多层级图卷积网络在挖掘实体间隐含结构联系上的补充作用。该方法为复杂语义场景下的关系抽取提供了高效解决方案。 展开更多
关键词 关系抽取 液态神经网络 图卷积网络 预训练模型 注意力门控 多层感知机
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GRAPH曲线在Pro/E中的应用
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作者 刘敏杰 《轻工机械》 CAS 2006年第3期62-64,共3页
介绍了GRAPH曲线在P ro/E中的应用,包括创建变节距螺旋扫描特征时对GRAPH曲线的修改、用曲面偏距法创建基准曲线时GRAPH曲线的建立,以及创建可变截面扫描特征时GRAPH曲线与关系式的配合使用,并分别结合实例进行了说明。
关键词 graph曲线 PRO/E 关系式
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融合Graph state LSTM与注意力机制的跨句多元关系抽取
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作者 衡红军 姚若男 《计算机应用与软件》 北大核心 2023年第8期214-220,290,共8页
已有的跨句多元关系抽取工作将输入文本表示为集成句内和句间依赖关系的复杂文档图,但图中包含的噪声信息会影响关系抽取的效果。针对这种情况,该文利用Graph state LSTM获得上下文信息,再分别利用词级注意力机制或位置感知的注意力机制... 已有的跨句多元关系抽取工作将输入文本表示为集成句内和句间依赖关系的复杂文档图,但图中包含的噪声信息会影响关系抽取的效果。针对这种情况,该文利用Graph state LSTM获得上下文信息,再分别利用词级注意力机制或位置感知的注意力机制,自动聚焦在对关系抽取起到决定性作用的关键词上,降低噪声信息的影响。并且比较了两种注意力机制对使用Graph state LSTM进行关系抽取的影响。通过在一个重要的精确医学数据集上进行实验,验证了该文所提出模型的有效性。 展开更多
关键词 跨句多元关系抽取 注意力机制 graph state LSTM
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Restage:Relation Structure-Aware Hierarchical Heterogeneous Graph Embedding
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作者 Huanjing Zhao Pinde Rui +2 位作者 Jie Chen Shu Zhao Yanping Zhang 《Tsinghua Science and Technology》 2025年第1期198-214,共17页
Heterogeneous graphs contain multiple types of entities and relations,which are capable of modeling complex interactions.Embedding on heterogeneous graphs has become an essential tool for analyzing and understanding s... Heterogeneous graphs contain multiple types of entities and relations,which are capable of modeling complex interactions.Embedding on heterogeneous graphs has become an essential tool for analyzing and understanding such graphs.Although these meticulously designed methods make progress,they are limited by model design and computational resources,making it difficult to scale to large-scale heterogeneous graph data and hindering the application and promotion of these methods.In this paper,we propose Restage,a relation structure-aware hierarchical heterogeneous graph embedding framework.Under this framework,embedding only a smaller-scale graph with existing graph representation learning methods is sufficient to obtain node representations on the original heterogeneous graph.We consider two types of relation structures in heterogeneous graphs:interaction relations and affiliation relations.Firstly,we design a relation structure-aware coarsening method to successively coarsen the original graph to the top-level layer,resulting in a smaller-scale graph.Secondly,we allow any unsupervised representation learning methods to obtain node embeddings on the top-level graph.Finally,we design a relation structure-aware refinement method to successively refine the node embeddings from the top-level graph back to the original graph,obtaining node embeddings on the original graph.Experimental results on three public heterogeneous graph datasets demonstrate the enhanced scalability of representation learning methods by the proposed Restage.On another large-scale graph,the speed of existing representation learning methods is increased by up to eighteen times at most. 展开更多
关键词 heterogeneous graph graph embedding relation structure HIERARCHICAL
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路径-维度GraphOLAP大规模多维网络并行分析框架 被引量:4
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作者 张子兴 吴斌 +4 位作者 吴心宇 张有杰 孙思瑞 彭程程 刘昱彤 《软件学报》 EI CSCD 北大核心 2018年第3期545-568,共24页
现实生活中,大量数据都可以使用多维网络进行建模.如何更好地对多维网络进行分析,是研究人员关注的重点.OLAP(联机分析处理)技术已被证实是对多维关系数据进行分析的有效工具,但应用OLAP技术管理与分析多维网络数据以支持有效决策,仍是... 现实生活中,大量数据都可以使用多维网络进行建模.如何更好地对多维网络进行分析,是研究人员关注的重点.OLAP(联机分析处理)技术已被证实是对多维关系数据进行分析的有效工具,但应用OLAP技术管理与分析多维网络数据以支持有效决策,仍是一项巨大的挑战.设计并提出了一种图立方体模型:路径-维度立方体,并针对提出的立方体模型将物化过程划分为关系路径物化与关联维度物化两部分,分别提出了物化策略,并基于Spark框架设计了相关算法.在此基础上,针对网络数据设计并细化了相关的Graph OLAP(图联机分析处理)操作,丰富了框架的分析角度,提高了对多维网络的分析能力.最后,在Spark上实现了相关算法,通过对多个真实应用场景中的数据构建多维网络,在分析框架上进行了分析,实验结果表明,所提出的图立方体模型和物化算法具有一定的有效性和可扩展性. 展开更多
关键词 图立方体 立方体物化 关系路径 图联机分析处理
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Learning Context-based Embeddings for Knowledge Graph Completion 被引量:6
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作者 Fei Pu Zhongwei Zhang +1 位作者 Yan Feng Bailin Yang 《Journal of Data and Information Science》 CSCD 2022年第2期84-106,共23页
Purpose:Due to the incompleteness nature of knowledge graphs(KGs),the task of predicting missing links between entities becomes important.Many previous approaches are static,this posed a notable problem that all meani... Purpose:Due to the incompleteness nature of knowledge graphs(KGs),the task of predicting missing links between entities becomes important.Many previous approaches are static,this posed a notable problem that all meanings of a polysemous entity share one embedding vector.This study aims to propose a polysemous embedding approach,named KG embedding under relational contexts(ContE for short),for missing link prediction.Design/methodology/approach:ContE models and infers different relationship patterns by considering the context of the relationship,which is implicit in the local neighborhood of the relationship.The forward and backward impacts of the relationship in ContE are mapped to two different embedding vectors,which represent the contextual information of the relationship.Then,according to the position of the entity,the entity’s polysemous representation is obtained by adding its static embedding vector to the corresponding context vector of the relationship.Findings:ContE is a fully expressive,that is,given any ground truth over the triples,there are embedding assignments to entities and relations that can precisely separate the true triples from false ones.ContE is capable of modeling four connectivity patterns such as symmetry,antisymmetry,inversion and composition.Research limitations:ContE needs to do a grid search to find best parameters to get best performance in practice,which is a time-consuming task.Sometimes,it requires longer entity vectors to get better performance than some other models.Practical implications:ContE is a bilinear model,which is a quite simple model that could be applied to large-scale KGs.By considering contexts of relations,ContE can distinguish the exact meaning of an entity in different triples so that when performing compositional reasoning,it is capable to infer the connectivity patterns of relations and achieves good performance on link prediction tasks.Originality/value:ContE considers the contexts of entities in terms of their positions in triples and the relationships they link to.It decomposes a relation vector into two vectors,namely,forward impact vector and backward impact vector in order to capture the relational contexts.ContE has the same low computational complexity as TransE.Therefore,it provides a new approach for contextualized knowledge graph embedding. 展开更多
关键词 Full expressiveness relational contexts Knowledge graph embedding relation patterns Link prediction
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