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A Two-Phase Paradigm for Joint Entity-Relation Extraction 被引量:2
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作者 Bin Ji Hao Xu +4 位作者 Jie Yu Shasha Li JunMa Yuke Ji Huijun Liu 《Computers, Materials & Continua》 SCIE EI 2023年第1期1303-1318,共16页
An exhaustive study has been conducted to investigate span-based models for the joint entity and relation extraction task.However,these models sample a large number of negative entities and negative relations during t... An exhaustive study has been conducted to investigate span-based models for the joint entity and relation extraction task.However,these models sample a large number of negative entities and negative relations during the model training,which are essential but result in grossly imbalanced data distributions and in turn cause suboptimal model performance.In order to address the above issues,we propose a two-phase paradigm for the span-based joint entity and relation extraction,which involves classifying the entities and relations in the first phase,and predicting the types of these entities and relations in the second phase.The two-phase paradigm enables our model to significantly reduce the data distribution gap,including the gap between negative entities and other entities,aswell as the gap between negative relations and other relations.In addition,we make the first attempt at combining entity type and entity distance as global features,which has proven effective,especially for the relation extraction.Experimental results on several datasets demonstrate that the span-based joint extraction model augmented with the two-phase paradigm and the global features consistently outperforms previous state-ofthe-art span-based models for the joint extraction task,establishing a new standard benchmark.Qualitative and quantitative analyses further validate the effectiveness the proposed paradigm and the global features. 展开更多
关键词 joint extraction span-based named entity recognition relation extraction data distribution global features
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Joint Feature Encoding and Task Alignment Mechanism for Emotion-Cause Pair Extraction
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作者 Shi Li Didi Sun 《Computers, Materials & Continua》 SCIE EI 2025年第1期1069-1086,共18页
With the rapid expansion of social media,analyzing emotions and their causes in texts has gained significant importance.Emotion-cause pair extraction enables the identification of causal relationships between emotions... With the rapid expansion of social media,analyzing emotions and their causes in texts has gained significant importance.Emotion-cause pair extraction enables the identification of causal relationships between emotions and their triggers within a text,facilitating a deeper understanding of expressed sentiments and their underlying reasons.This comprehension is crucial for making informed strategic decisions in various business and societal contexts.However,recent research approaches employing multi-task learning frameworks for modeling often face challenges such as the inability to simultaneouslymodel extracted features and their interactions,or inconsistencies in label prediction between emotion-cause pair extraction and independent assistant tasks like emotion and cause extraction.To address these issues,this study proposes an emotion-cause pair extraction methodology that incorporates joint feature encoding and task alignment mechanisms.The model consists of two primary components:First,joint feature encoding simultaneously generates features for emotion-cause pairs and clauses,enhancing feature interactions between emotion clauses,cause clauses,and emotion-cause pairs.Second,the task alignment technique is applied to reduce the labeling distance between emotion-cause pair extraction and the two assistant tasks,capturing deep semantic information interactions among tasks.The proposed method is evaluated on a Chinese benchmark corpus using 10-fold cross-validation,assessing key performance metrics such as precision,recall,and F1 score.Experimental results demonstrate that the model achieves an F1 score of 76.05%,surpassing the state-of-the-art by 1.03%.The proposed model exhibits significant improvements in emotion-cause pair extraction(ECPE)and cause extraction(CE)compared to existing methods,validating its effectiveness.This research introduces a novel approach based on joint feature encoding and task alignment mechanisms,contributing to advancements in emotion-cause pair extraction.However,the study’s limitation lies in the data sources,potentially restricting the generalizability of the findings. 展开更多
关键词 Emotion-cause pair extraction interactive information enhancement joint feature encoding label consistency task alignment mechanisms
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A Review of Joint Extraction Techniques for Relational Triples Based on NYT and WebNLG Datasets
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作者 Chenglong Mi Huaibin Qin +1 位作者 Quan Qi Pengxiang Zuo 《Computers, Materials & Continua》 2025年第3期3773-3796,共24页
In recent years,with the rapid development of deep learning technology,relational triplet extraction techniques have also achieved groundbreaking progress.Traditional pipeline models have certain limitations due to er... In recent years,with the rapid development of deep learning technology,relational triplet extraction techniques have also achieved groundbreaking progress.Traditional pipeline models have certain limitations due to error propagation.To overcome the limitations of traditional pipeline models,recent research has focused on jointly modeling the two key subtasks-named entity recognition and relation extraction-within a unified framework.To support future research,this paper provides a comprehensive review of recently published studies in the field of relational triplet extraction.The review examines commonly used public datasets for relational triplet extraction techniques and systematically reviews current mainstream joint extraction methods,including joint decoding methods and parameter sharing methods,with joint decoding methods further divided into table filling,tagging,and sequence-to-sequence approaches.In addition,this paper also conducts small-scale replication experiments on models that have performed well in recent years for each method to verify the reproducibility of the code and to compare the performance of different models under uniform conditions.Each method has its own advantages in terms of model design,task handling,and application scenarios,but also faces challenges such as processing complex sentence structures,cross-sentence relation extraction,and adaptability in low-resource environments.Finally,this paper systematically summarizes each method and discusses the future development prospects of joint extraction of relational triples. 展开更多
关键词 Relation triplet extraction joint extraction methods named entity recognition relation extraction
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Joint Biomedical Entity and Relation Extraction Based on Multi-Granularity Convolutional Tokens Pairs of Labeling
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作者 Zhaojie Sun Linlin Xing +2 位作者 Longbo Zhang Hongzhen Cai Maozu Guo 《Computers, Materials & Continua》 SCIE EI 2024年第9期4325-4340,共16页
Extracting valuable information frombiomedical texts is one of the current research hotspots of concern to a wide range of scholars.The biomedical corpus contains numerous complex long sentences and overlapping relati... Extracting valuable information frombiomedical texts is one of the current research hotspots of concern to a wide range of scholars.The biomedical corpus contains numerous complex long sentences and overlapping relational triples,making most generalized domain joint modeling methods difficult to apply effectively in this field.For a complex semantic environment in biomedical texts,in this paper,we propose a novel perspective to perform joint entity and relation extraction;existing studies divide the relation triples into several steps or modules.However,the three elements in the relation triples are interdependent and inseparable,so we regard joint extraction as a tripartite classification problem.At the same time,fromthe perspective of triple classification,we design amulti-granularity 2D convolution to refine the word pair table and better utilize the dependencies between biomedical word pairs.Finally,we use a biaffine predictor to assist in predicting the labels of word pairs for relation extraction.Our model(MCTPL)Multi-granularity Convolutional Tokens Pairs of Labeling better utilizes the elements of triples and improves the ability to extract overlapping triples compared to previous approaches.Finally,we evaluated our model on two publicly accessible datasets.The experimental results show that our model’s ability to extract relation triples on the CPI dataset improves the F1 score by 2.34%compared to the current optimal model.On the DDI dataset,the F1 value improves the F1 value by 1.68%compared to the current optimal model.Our model achieved state-of-the-art performance compared to other baseline models in biomedical text entity relation extraction. 展开更多
关键词 Deep learning BIOMEDICAL joint extraction triple classification multi-granularity 2D convolution
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Knowledge-enriched joint-learning model for implicit emotion cause extraction
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作者 Chenghao Wu Shumin Shi +1 位作者 Jiaxing Hu Heyan Huang 《CAAI Transactions on Intelligence Technology》 SCIE EI 2023年第1期118-128,共11页
Emotion cause extraction(ECE)task that aims at extracting potential trigger events of certain emotions has attracted extensive attention recently.However,current work neglects the implicit emotion expressed without an... Emotion cause extraction(ECE)task that aims at extracting potential trigger events of certain emotions has attracted extensive attention recently.However,current work neglects the implicit emotion expressed without any explicit emotional keywords,which appears more frequently in application scenarios.The lack of explicit emotion information makes it extremely hard to extract emotion causes only with the local context.Moreover,an entire event is usually across multiple clauses,while existing work merely extracts cause events at clause level and cannot effectively capture complete cause event information.To address these issues,the events are first redefined at the tuple level and a span-based tuple-level algorithm is proposed to extract events from different clauses.Based on it,a corpus for implicit emotion cause extraction that tries to extract causes of implicit emotions is constructed.The authors propose a knowledge-enriched jointlearning model of implicit emotion recognition and implicit emotion cause extraction tasks(KJ-IECE),which leverages commonsense knowledge from ConceptNet and NRC_VAD to better capture connections between emotion and corresponding cause events.Experiments on both implicit and explicit emotion cause extraction datasets demonstrate the effectiveness of the proposed model. 展开更多
关键词 emotion cause extraction external knowledge fusion implicit emotion recognition joint learning
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Joint Extraction of Uygur Medicine Knowledge with Edge Computing
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作者 Fan Lu Quan Qi Huaibin Qin 《Tsinghua Science and Technology》 2025年第2期782-795,共14页
Edge computing,a novel paradigm for performing computations at the network edge,holds significant relevance in the healthcare domain for extracting medical knowledge from traditional Uygur medical texts.Medical knowle... Edge computing,a novel paradigm for performing computations at the network edge,holds significant relevance in the healthcare domain for extracting medical knowledge from traditional Uygur medical texts.Medical knowledge extraction methods based on edge computing deploy deep learning models on edge devices to achieve localized entity and relation extraction.This approach avoids transferring substantial sensitive data to cloud data centers,effectively safeguarding the privacy of healthcare services.However,existing relation extraction methods mainly employ a sequential pipeline approach,which classifies relations between determined entities after entity recognition.This mode faces challenges such as error propagation between tasks,insufficient consideration of dependencies between the two subtasks,and the neglect of interrelations between different relations within a sentence.To address these challenges,a joint extraction model with parameter sharing in edge computing is proposed,named CoEx-Bert.This model leverages shared parameterization between two models to jointly extract entities and relations.Specifically,CoEx-Bert employs two models,each separately sharing hidden layer parameters,and combines these two loss functions for joint backpropagation to optimize the model parameters.Additionally,it effectively resolves the issue of entity overlapping when extracting knowledge from unstructured Uygur medical texts by considering contextual relations.Finally,this model is deployed on edge devices for real-time extraction and inference of Uygur medical knowledge.Experimental results demonstrate that CoEx-Bert outperforms existing state-of-the-art methods,achieving accuracy,recall,and F1-score of 90.65%,92.45%,and 91.54%,respectively,in the Uygur traditional medical literature dataset.These improvements represent a 6.45%increase in accuracy,a 9.45%increase in recall,and a 7.95%increase in F1-score compared to the baseline. 展开更多
关键词 BERT pre-training joint extraction edge computing
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Deep learning models for spatial relation extraction in text
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作者 Kehan Wu Xueying Zhang +1 位作者 Yulong Dang Peng Ye 《Geo-Spatial Information Science》 SCIE EI CSCD 2023年第1期58-70,共13页
Spatial relation extraction is the process of identifying geographic entities from text and determining their corresponding spatial relations.Traditional spatial relation extraction mainly uses rule-based pattern matc... Spatial relation extraction is the process of identifying geographic entities from text and determining their corresponding spatial relations.Traditional spatial relation extraction mainly uses rule-based pattern matching,supervised learning-based or unsupervised learning-based methods.However,these methods suffer from poor time-sensitive,high labor cost and high dependence on large-scale data.With the development of pre-trained language models greatly alleviating the shortcomings of traditional methods,supervised learning methods incorporating pre-trained language models have become the mainstream relation extraction methods.Pipeline extraction and joint extraction,as the two most dominant ideas of relation extraction,both have obtained good performance on different datasets,and whether to share the contextual information of entities and relations is the main differences between the two ideas.In this paper,we compare the performance of two ideas oriented to spatial relation extraction based on Chinese corpus data in the field of geography and verify which method based on pre-trained language models is more suitable for Chinese spatial relation extraction.We fine-tuned the hyperparameters of the two models to optimize the extraction accuracy before the comparison experiments.The results of the comparison experiments show that pipeline extraction performs better than joint extraction of spatial relation extraction for Chinese text data with sentence granularity,because different tasks have different focus on contextual information,and it is difficult to take account into the needs of both tasks by sharing contextual information.In addition,we further compare the performance of the two models with the rule-based template approach in extracting topological,directional and distance relations,summarize the shortcomings of this experiment and provide an outlook for future work. 展开更多
关键词 Spatial relation extraction pre-trained language model pipeline extraction joint extraction
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基于大语言模型和提示学习的旅游文本实体关系联合抽取方法 被引量:1
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作者 徐春 苏明钰 +2 位作者 马欢 吉双焱 王萌萌 《数据分析与知识发现》 北大核心 2025年第7期130-140,共11页
【目的】针对旅游领域知识分散、标注数据有限导致的微调效率低、抽取性能不佳等问题,进行小样本场景下实体关系抽取方法的研究。【方法】基于大模型GLM进行旅游领域的提示学习后,对输入文本进行编码表示,结合全局指针网络完成潜在关系... 【目的】针对旅游领域知识分散、标注数据有限导致的微调效率低、抽取性能不佳等问题,进行小样本场景下实体关系抽取方法的研究。【方法】基于大模型GLM进行旅游领域的提示学习后,对输入文本进行编码表示,结合全局指针网络完成潜在关系预测和特定关系下的实体识别,抽取关系三元组。【结果】在自建旅游数据集和百度DuIE数据集上进行实验,本文模型的F1值分别为90.51%和89.45%,较传统关系抽取模型分别提升2.37和0.16个百分点。【局限】提示学习仅应用于旅游领域和特定编码器,在应用场景方面还有拓展空间。【结论】本文方法能够更好地对旅游文本进行实体关系联合抽取,提示学习和大语言模型编码器可以缓解小样本场景下模型训练效果不佳的问题,有效提高实体关系抽取的准确率。 展开更多
关键词 实体关系抽取 大语言模型 提示学习 全局指针网络
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基于图像匹配的钢丝绳芯输送带接头抽动自动检测 被引量:1
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作者 李现国 郭宽宽 苗长云 《天津工业大学学报》 北大核心 2025年第2期78-83,共6页
针对钢丝绳芯输送带接头抽动检测有效性和准确性差的问题,提出一种基于图像匹配的钢丝绳芯输送带接头抽动自动检测方法。首先进行图像预处理,提高图像质量;然后使用自动阈值提取钢丝绳端头点;再利用改进的ORB算法进行图像匹配,将待检测... 针对钢丝绳芯输送带接头抽动检测有效性和准确性差的问题,提出一种基于图像匹配的钢丝绳芯输送带接头抽动自动检测方法。首先进行图像预处理,提高图像质量;然后使用自动阈值提取钢丝绳端头点;再利用改进的ORB算法进行图像匹配,将待检测图像和基准图像中的钢丝绳端头点一一对应;最后采用基于钢丝绳端头基准点集的接头抽动测量方法计算接头抽动量并进行故障定位。实验结果表明:本文方法能够自动检测并标识出钢丝绳芯输送带接头处的钢丝绳端头点,准确得到钢丝绳端头点的匹配点对,计算出单个钢丝绳端头抽动量、钢丝绳上(下)端头平均抽动量和接头整体抽动量,检测并标识出异常钢丝绳端头的位置和变化量,实现了对接头抽动的自动检测和综合判断。 展开更多
关键词 钢丝绳芯输送带 接头抽动 图像匹配 钢丝绳端头点提取 ORB算法
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一种融合语义特征和多层交叉注意力机制的中药专利文本实体关系联合抽取模型 被引量:2
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作者 邓娜 喻卓群 +2 位作者 但文俊 陈旭 刘树栋 《数据分析与知识发现》 北大核心 2025年第7期141-153,共13页
【目的】解决中药专利文本中实体重叠和关系复杂的问题,提升中药成分、药理疗效、优点等实体关系的抽取精度。【方法】提出一种中药专利文本实体关系联合抽取模型TPSCRE:结合词性标注网络和CDILCNN增强模型对中药专利文本的语义理解,利... 【目的】解决中药专利文本中实体重叠和关系复杂的问题,提升中药成分、药理疗效、优点等实体关系的抽取精度。【方法】提出一种中药专利文本实体关系联合抽取模型TPSCRE:结合词性标注网络和CDILCNN增强模型对中药专利文本的语义理解,利用双重Cross-Attention机制生成多样化词表示以增强实体和关系的信息交互和互补,通过对抗学习策略提高模型对潜在错误标注数据的鲁棒性和泛化能力;构建主客体对应矩阵过滤出正确的中药专利实体关系三元组。【结果】在自建中药专利数据集上进行对比实验和消融实验,结果表明本文提出的TPSCRE模型表现最优,在中药实体识别和关系抽取上F1值分别为94.71%和87.56%。【局限】模型复杂度和计算成本较高,评估标准受限于现有数据集的规模。【结论】TPSCRE模型能更好地捕捉中药文本中实体间的复杂关系,在中药专利文本实体关系的联合抽取任务中有显著性能优势。 展开更多
关键词 中药专利 实体关系联合抽取 词性特征 交叉注意力机制 对抗学习
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面向设备运维的人机物三元融合知识图谱构建方法
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作者 杨波 申小玉 +2 位作者 王时龙 何彦 杜卡泽 《机械工程学报》 北大核心 2025年第17期215-232,共18页
设备运维是保障生产正常进行的重要基础,现有的智能运维技术主要依赖信号分析、数据挖掘或专家知识重用。然而,随着设备自动化和集成化程度的提高,其各类运行异常的表征信号、多源致因和维护方案之间的关系呈现出更高的模糊性和复杂性,... 设备运维是保障生产正常进行的重要基础,现有的智能运维技术主要依赖信号分析、数据挖掘或专家知识重用。然而,随着设备自动化和集成化程度的提高,其各类运行异常的表征信号、多源致因和维护方案之间的关系呈现出更高的模糊性和复杂性,将信号、数据和知识进行融合分析是提高设备运维精度和效率的关键。为此,采用知识图谱技术将“人”、“机”、“物”三元数据融合来支撑复杂设备的异常诊断和维护方案决策,提高运维智能化程度、避免决策片面性。首先,对设备运维领域人机物三元数据进行定义并完成三元本体设计,指导知识图数据层的构建。其次,对人机物三元数据进行预处理并搭建了统一混合注意力机制联合抽取模型(Joint entity and relation extraction model with mixed attention,MAREL)从三元数据中自动抽取知识,并建立三元知识之间的关联关系,以此实现人机物三元数据的融合;MAREL模型将任务拆解为两个关联的解码模块来解决实体重叠问题,利用混合注意力机制增强模型的长文本处理能力,在中文数据集SKE上的测试证明MAREL具有优异的性能。最后,以某汽车生产机器人设备运维人机物知识图谱的构建为例,验证了所提方法的有效性,结果表明知识图谱能够将人机物三元数据有效融合,为工业设备的智能运维提供支持。 展开更多
关键词 设备运维 人机物 知识图谱 数据融合 本体 联合抽取
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基于改进集合预测网络的输变电设备故障知识图谱构建方法
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作者 阎光伟 张云馨 +1 位作者 符哲源 焦润海 《电工技术学报》 北大核心 2025年第15期4976-4987,共12页
输变电系统作为电网的重要组成部分,其设备一旦发生故障会造成不可预计的损失。知识图谱通过存储结构化的领域知识,已成为辅助电力领域专业人员进行故障分析与决策的有力工具。实体关系抽取是知识图谱构建中的关键步骤,现有实体关系抽... 输变电系统作为电网的重要组成部分,其设备一旦发生故障会造成不可预计的损失。知识图谱通过存储结构化的领域知识,已成为辅助电力领域专业人员进行故障分析与决策的有力工具。实体关系抽取是知识图谱构建中的关键步骤,现有实体关系抽取方法通常忽略了三元组之间的依赖,且存在文本表征能力弱、实体定位模糊及长尾关系分类精确率不高的问题。针对以上问题,该文提出了一种基于改进集合预测网络的实体关系联合抽取模型。该模型基于集合预测网络结构对三元组进行整体建模,首先利用无监督对比学习方式增强输入文本表征,为后续实体关系抽取提供更有效的语义特征;其次利用边界回归算法对实体边界的偏移量进行建模,在网络预测的基础上进一步通过偏移量来修正实体边界,提高实体的识别准确率;最后在关系分类阶段引入代价敏感学习来平衡不同类型三元组的损失,使模型在长尾分布及高错分代价约束下有效地学习长尾关系的特征,降低长尾关系分类的错误率,并且在实际输变电设备故障数据集上进行验证,进而以此构建输变电设备故障知识图谱。在实体关系抽取实验中,精确率、召回率和F1值相较于基线模型分别提升了3.9、5.3、4.6个百分点,实验结果表明,该文所提模型在输变电设备故障数据上能够实现有效的实体关系抽取。此外,该文利用Neo4j图数据库对构建的知识图谱进行存储和可视化,构建的知识图谱能够为后续故障分析和决策提供支持。 展开更多
关键词 输变电设备 知识图谱 联合抽取 对比学习 边界回归
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基于关系提示的单模块单步骤实体关系抽取方法研究
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作者 刘辉 张智 王启源 《西安交通大学学报》 北大核心 2025年第3期222-234,共13页
针对现有关系三元组抽取方法由于忽略关系本身的关系语义信息以及三元组中元素的相互依赖和不可分性所导致的抽取效果不佳问题,提出了一种基于关系提示的实体关系抽取方法。在构建单模块单步关系三重抽取模型(RPSS)的基础上,考虑不同层... 针对现有关系三元组抽取方法由于忽略关系本身的关系语义信息以及三元组中元素的相互依赖和不可分性所导致的抽取效果不佳问题,提出了一种基于关系提示的实体关系抽取方法。在构建单模块单步关系三重抽取模型(RPSS)的基础上,考虑不同层次的关系语义信息和符号级和特征级的关系提示信息,对实体和关系提示符进行联合编码,得到统一的全局表示;同时通过注意力机制挖掘不同嵌入之间的深层关联,构建三重交互矩阵,可在一个步骤中直接从单个模块中提取所有三元组。结果表明:所提方法在NYT、WebNLG两个基准数据集上实现了最佳的表现,F_(1)分别达到了93.3%和94.9%。 展开更多
关键词 实体关系抽取 注意力机制 联合编码
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基于混合关联度的联合实体与关系抽取
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作者 马长林 宋玉婷 《华中科技大学学报(自然科学版)》 北大核心 2025年第5期38-43,57,共7页
针对重叠三元组的联合抽取问题,提出一个基于混合关联度的级联关系三重抽取模型.本模型首先引入位置关系来构造关联度编码器,联合双向转换器表示编码器(BERT)形成双编码器结构,将输入文本转化为带有上下文语义和词-句关联信息的词向量;... 针对重叠三元组的联合抽取问题,提出一个基于混合关联度的级联关系三重抽取模型.本模型首先引入位置关系来构造关联度编码器,联合双向转换器表示编码器(BERT)形成双编码器结构,将输入文本转化为带有上下文语义和词-句关联信息的词向量;然后,将词嵌入向量输入实体标记解码器,采用级联二进制标注表对所有可能出现的头实体的开始和结束位置进行标注,得到候选头实体集合;最后,将融合了混合关联度的候选头实体集作为关系-对象标记解码器的输入,进行对象和实体对关系的识别.在百度和纽约时报两个数据集上的实验结果表明:与已有模型相比,本研究模型在各评估指标上均有所提升,验证了所提出方法的有效性. 展开更多
关键词 联合抽取 重叠三元组 混合关联度 级联二进制 位置邻近和重叠算法
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基于跨度和多层次特征融合的实体关系联合抽取
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作者 廖涛 许锦涛 张顺香 《阜阳师范大学学报(自然科学版)》 2025年第1期15-22,54,共9页
针对目前方法大多未能充分利用跨度语义信息和局部上下文隐含信息等问题,提出基于跨度和多层次特征融合的实体关系联合抽取模型。该模型首先将文本输入到预训练语言模型(Bidirectional Encoder Representations from Transformer,BERT)... 针对目前方法大多未能充分利用跨度语义信息和局部上下文隐含信息等问题,提出基于跨度和多层次特征融合的实体关系联合抽取模型。该模型首先将文本输入到预训练语言模型(Bidirectional Encoder Representations from Transformer,BERT)转换为词向量后,将其与通过图卷积获得的句法依赖信息进行融合,形成更丰富的文本特征;然后通过多头注意力层对文本特征进行加权处理,以此抑制噪声特征的干扰,并促进特征之间的交互,随后根据跨度将文本信息分割成跨度序列进行实体识别;最后使用双向门控循环单元提取局部上下文隐含信息,将与实体类型信息融合到候选实体跨度对并使用sigmoid函数进行关系分类。实验表明,该模型在SciERC数据集和CoNLL04数据集上取得良好的提升效果。 展开更多
关键词 实体关系 联合抽取 句法依赖 跨度 多特征融合 多头注意力
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基于知识图谱的在线健康社区医疗专家专长领域识别及评价方法研究
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作者 席运江 张倩 +1 位作者 李曼 于娟 《科技情报研究》 2025年第4期24-34,共11页
[目的/意义]文章旨在识别在线健康社区中医疗专家的专长领域并评估其专业水平,为社区内专家推荐提供依据。[方法/过程]采用改进的OneRel模型,将在线健康社区中的历史问答结构化为实体关系三元组。基于知识图谱三元组,检验社区问答中的... [目的/意义]文章旨在识别在线健康社区中医疗专家的专长领域并评估其专业水平,为社区内专家推荐提供依据。[方法/过程]采用改进的OneRel模型,将在线健康社区中的历史问答结构化为实体关系三元组。基于知识图谱三元组,检验社区问答中的医疗知识与领域知识的一致性,再按照专长领域汇总上述一致性检验结果,得到医生在不同领域的可信度,以此作为衡量医生专长水平的依据。[结果/结论]以“寻医问药网”为例,对社区内214名医生专长水平进行排名,确定各自可信的领域。研究验证了在线健康社区中医生自行填写的诊疗专长、个人简介等基本信息与其真实专长领域不完全一致。与传统医疗专家发现方法相比,本方法具有客观、准确、可解释性强等特点,能够智能识别及评价医生的专长领域。 展开更多
关键词 在线健康社区 专家发现 知识图谱 实体关系联合抽取 可信性
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基于信号到达时间建模的广域多点定位时间同步方法 被引量:2
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作者 汤新民 周杨 +1 位作者 鲁其兴 管祥民 《电子与信息学报》 北大核心 2025年第5期1434-1449,共16页
针对低空监视技术广域多点定位(WAM)时间同步困难或复杂度高,影响定位精度的问题,该文构建了基于到达时间(TOA)的时间同步及“同一消息”提取的数学模型,通过计算地面传感器的“同步启动时间”完成同步,计算复杂度低且易于实现。在此基... 针对低空监视技术广域多点定位(WAM)时间同步困难或复杂度高,影响定位精度的问题,该文构建了基于到达时间(TOA)的时间同步及“同一消息”提取的数学模型,通过计算地面传感器的“同步启动时间”完成同步,计算复杂度低且易于实现。在此基础上,利用同一消息提取模型筛选出TOA用于定位计算。为了提高TOA估计值的精度,减小同步误差。提出了可变滑动滤波与卡尔曼滤波结合(VMAF-Kalman)的联合滤波方法,提高可编程门阵列(FPGA)基准时钟的稳定性,减小时钟延迟引起的TOA计数误差。仿真结果表明,联合滤波比单一滤波算法效果更好,TOA计数误差分别降低36.84%和25.36%。对无人机和民航飞机的定位测验结果都表现出较高的定位准确率,定位误差和位置更新速率符合标准要求,证明该文所提模型,具有实用性且有较好的同步精度。 展开更多
关键词 广域多点定位系统 到达时间 联合滤波 时间同步 同一消息提取
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末端位置表达下机器人执行器抓取力控制 被引量:1
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作者 褚含冰 张娴静 贾更新 《机械设计与制造》 北大核心 2025年第6期302-307,共6页
机器人的末端执行器通常由多个关节和连杆组成,其位置和姿态涉及复杂的运动学。由于机器人工作空间的非线性特性、关节间的耦合效应等因素,精确计算末端执行器的位置变得非常复杂,导致机器人在动态环境中执行抓取动作时抓取力控制难度... 机器人的末端执行器通常由多个关节和连杆组成,其位置和姿态涉及复杂的运动学。由于机器人工作空间的非线性特性、关节间的耦合效应等因素,精确计算末端执行器的位置变得非常复杂,导致机器人在动态环境中执行抓取动作时抓取力控制难度极大。为此,提出了机器人末端执行器抓取力控制。确定驱动关节参数,引入机器人的D-H参数,建立相邻关节坐标系的齐次变换矩阵,获得末端执行器位置,清晰描述机器人连杆和关节之间的相对几何关系;基于此,建立相机、图像、像素和末端执行器位置坐标系映射关系,得到内、外参数矩阵,提取虚拟位姿。通过阻抗算法与PD控制算法求解虚拟位姿期望的机器人末端执行器加速度,结合逆动力学获取各关节的驱动力,并将接触力与关节角度、关节角速度等数据输入到控制器内,完成机器人末端执行器抓取力控制。通过实验结果可知,研究方法控制下,机器人末端执行器关节的角度在(-0.10~0.09)rad之间波动,波动范围非常小,证明所提方法能够有效控制机器人末端执行器抓取力,实现稳定且准确地抓取物体,避免了滑落或损坏。 展开更多
关键词 虚拟位姿提取 抓取力控制 机器人末端执行器 接触力矩 关节响应
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基于片段排列和多头选择的实体识别与关系抽取联合模型
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作者 陈雷 郑小盈 +1 位作者 祝永新 封松林 《计算机应用与软件》 北大核心 2025年第5期238-246,共9页
针对传统的信息抽取方法存在实体重叠、误差积累和依赖关系缺失等问题,该文提出一种基于片段排列和多头选择的实体识别与关系抽取联合模型。通过共享编码层来建立实体识别与关系抽取之间的依赖;通过片段排列的方式在span的层面解决实体... 针对传统的信息抽取方法存在实体重叠、误差积累和依赖关系缺失等问题,该文提出一种基于片段排列和多头选择的实体识别与关系抽取联合模型。通过共享编码层来建立实体识别与关系抽取之间的依赖;通过片段排列的方式在span的层面解决实体重叠问题;使用多头选择机制来预测实体之间的关系,并加入对抗训练,通过辅助损失函数进行约束。通过消融实验和基于不同权重损失函数的实验,找到了效果最好的参数。该模型在中文数据集DuIE 2.0上取得了F1值0.829的效果,相对于效果最好的基线模型提升2.24%。 展开更多
关键词 实体关系抽取 联合抽取 多头选择 片段排列模型
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多模态唐卡知识图谱构建研究
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作者 赵婉亦 赵维纳 +3 位作者 马龙龙 耿生玲 周明全 安波 《中文信息学报》 北大核心 2025年第8期53-64,共12页
唐卡绘画艺术作品是非常珍贵的非物质文化遗产,其数字化保护与传承在教育、艺术等领域具有重要的价值和意义。唐卡拥有丰富的多模态数据,该文首先通过Tk-SENet模型对唐卡图像进行细粒度分类;其次参考本体构建七步法,提出针对唐卡领域的... 唐卡绘画艺术作品是非常珍贵的非物质文化遗产,其数字化保护与传承在教育、艺术等领域具有重要的价值和意义。唐卡拥有丰富的多模态数据,该文首先通过Tk-SENet模型对唐卡图像进行细粒度分类;其次参考本体构建七步法,提出针对唐卡领域的本体构建四步法;在提示学习框架下利用ERNIE预训练模型作为编码层,结合指针网络提出面向唐卡文本实体及关系的联合抽取模型,实现低资源下的知识抽取。对于不同数据源的唐卡知识,利用余弦相似度计算实体及关系的词频向量相似度进行知识融合。利用Neo4j图数据库进行知识存储,结合Echarts做可视化展示,形成多模态唐卡知识图谱,服务于青藏高原热贡艺术数字博物馆,实现对非物质文化遗产的弘扬与保护。 展开更多
关键词 多模态 唐卡知识图谱 联合抽取 数字博物馆
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