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1.
文档级实体关系抽取的主要任务是提取文档中实体之间的关系.相较于句内实体关系提取,文档级实体关系抽取需要对文档中多个句子进行推理.为了解决文档中不同实体之间的复杂信息交互问题,提出一个混合提及级图MMLG (Mixed Mention-Level Graph)策略,用于拟合文档中不同实体之间的复杂信息交互,提高模型对于文档级实体关系的感知能力.此外,为了应对实体关系中存在的关系重叠问题,构建了实体关系图ERG (Entity Relation Graph)模块,该模块融合了路径推理机制,主要针对实体间的多个关系路径进行推理学习,更准确地识别提及级节点实体及关系.通过将MMLG策略与ERG模块聚合到实体关系抽取模型中,构建BoBGSAL-Net (Based on Bipartite Graph Structure Aggregate Logic Network)模型,并在公开数据集DocRED和作者实验室构建的数据集AlSiaRED上开展实验,结果证明BoBGSAL-Net在文档级实体关系抽取任务中性能得到提升,其中BoBGSAL-Net+BERT模型在AlSiaRED数据集上的关系抽取...  相似文献   

2.
知识抽取任务是从非结构化的文本数据抽取三元组关系(头实体-关系-尾实体)。现有知识抽取方法分为流水式方法和联合抽取方法。流水式方法将命名实体识别和实体知识抽取分别用各自的模块抽取,这种方式虽然有较好的灵活性,但训练速度较慢。联合抽取的学习模型是一种通过神经网络实现的端到端的模型,同时实现实体识别和知识抽取,能够很好地保留实体和关系之间的关联,将实体和关系的联合抽取转化为一个序列标注问题。基于此,本文提出了一种基于字词混合和门控制单元(Gated Recurrent Unit, GRU)的科技文本知识抽取(MBGAB)方法,结合注意力机制提取中文科技资源文本的关系;采用字词混合的向量映射方式,既在最大程度上避免边界切分出错,又有效融入语义信息;采用端到端的联合抽取模型,利用双向GRU网络,结合自注意力机制来有效捕获句子中的长距离语义信息,并且通过引入偏置权重来提高模型抽取效果。  相似文献   

3.
针对信息与通信技术(information and communication,ICT)项目及产品数据种类多、形式复杂,难以提取其语义匹配信息,且现有句子级文本匹配模型对不同长度文本无差别编码会引入噪声导致匹配效果差的问题,本文提出一种融合局部和全局特征的实体-文档级联合匹配模型,利用TextCNN编码器提取实体级招投标项目和产品名称的局部信息,消除产品描述中与招投标项目无关信息的影响,再利用卷积-自注意力编码器提取文档级产品描述的局部和全局信息,最后结合实体级和文档级匹配信息进行决策.实验结果表明,招投标项目与供应商产品匹配映射准确率92%以上,方法可直接实际应用.   相似文献   

4.
通过结合2 738个领域词汇组成的词典对新疆旅游领域语料进行预处理操作,对文本信息进行实体关系抽取研究,提出基于旅游领域的词典信息,融合多级特征的Bi-LSTM、CNN和Attention机制的领域级关系抽取模型.该模型首先使用预训练模型生成含较强的语义表征能力的词向量;再使用Bi-LSTM获取更好的语义信息和词向量拼接以捕获长距离的语义特征;用CNN进行特征提取,加强局部特征的学习,并使用注意力池化层(Attentive-pooling)用以强化特征的表达;最后通过Softmax完成关系抽取任务.结果表明:该模型在SemEval-2010 Task 8公开数据集中F1值达到83.46%,证明了其有效性.且模型在新疆旅游领域语料的关系抽取任务中的F1值达到92.73%,优于目前的主流关系抽取模型.  相似文献   

5.
实体关系抽取作为文本挖掘和信息抽取的核心任务,是知识图谱构建过程中的关键一环。然而人工建立大规模有标签的数据耗时耗力。使用小样本学习来进行关系抽取,仅仅需要少量样本实例就能使模型学会区分不同关系类型的能力,从而缓解大量无标签数据带来的标注压力。本文对中文关系抽取数据集FinRE进行了重构使之适用于少样本学习,并引入了语义关系网络HowNet对实体进行更为精确的语义划分,并在此基础上使用双重注意力机制提高句子编码质量,从而提高了模型在面对噪声数据时的效能,减轻了长尾关系的影响。使用本文的方法在该中文数据集进行了评估,与原始原型网络相比,基于句子级别与实体级别的注意力机制的原型网络在抽取准确率上提升了1%~2%的性能。  相似文献   

6.
为了区分文档间的同源性和异质性,首先,提出一种多特征语义融合模型(Multi-Feature Semantic Fusion Model,MFSFM)来捕获文档关键字,它采用语义增强的多特征表示法来表示实体,并在多卷积混合残差CNN模块中引入局部注意力机制以提高实体边界信息的敏感性;然后,通过对文档构建一个关键字共现图,并应用社区检测算法检测概念进而表示文档,从而匹配文档对;最后,建立两个多特征文档数据集,以验证所提出的基于MFSFM的匹配方法的可行性,每一个数据集都包含约500份真实的科技项目可行性报告。研究结果表明:本文所提出的模型在CNSR和CNSI数据集上的分类精度分别提高了13.67%和15.83%,同时可以实现快速收敛。  相似文献   

7.
在新闻推荐场景下,传统的基于文本特征的新闻推荐模型只考虑了词的共现关系,无法捕获词语的隐含词义和关联知识;而基于深度学习的推荐模型在融合知识图谱信息中仅仅考虑实体的信息,忽略了远距离实体之间的联系,造成实体之间的关联信息和深层次语义联系的缺失.针对该问题提出了一种基于知识增强的深度新闻推荐网络(deep knowledge-enhanced network,DKEN),利用长短期记忆网络提取知识图谱中的实体路径特征,补充到注意力网络中,然后针对不同的候选新闻动态地构建用户的特征.实验表明该实体路径信息能提高模型的效果,在F1指标上提升大约1%.   相似文献   

8.
基于CNN-BLSTM的食品舆情实体关系抽取模型研究   总被引:1,自引:0,他引:1  
食品舆情实体关系抽取是构建食品舆情知识图谱的关键技术,也是当前信息抽取领域的重要研究课题。针对食品舆情中常出现的实体对多关系问题,在卷积神经网络(convolutional neural network,CNN)中引入基于位置感知的领域词语义注意力机制;在双向长短时记忆(bidirectional long short-term memory,BLSTM)网络中引入基于位置感知的语义角色注意力机制,构建基于CNN-BLSTM的食品舆情实体关系抽取模型。在食品舆情数据集上进行了对比实验,实验结果表明:基于CNN-BLSTM的食品舆情实体关系抽取模型在食品舆情数据集上准确率比常用的几种深度神经网络模型高出8.7%~13.94%,验证了模型的合理性和有效性。  相似文献   

9.
施工组织设计是指导工程建设全过程活动的技术、经济和组织的综合性文件,随着自然语言处理(NLP)等人工智能技术的发展,本文针对施工组织设计文档智慧辅助审查中基础性工作之一-文本分类问题开展研究。为实现施工组织设计文本的自动分类,本文运用Word2vec词嵌入技术对文本进行向量化表示,基于Bi-LSTM捕捉文本上下文序列信息,融入Attention机制,提取文本有效信息,采用softmax激活函数分类。Attention Bi-LSTM在房建数据集上达到了0.97的准确率、召回率以及F1值,整体分类效果在正确率、宏平均、加权平均上均优于其他模型。融入Attention机制的Bi-LSTM文本分类模型通过双向捕获文本的特征并利用Attention机制提取有效信息,达到了联合优化的作用,提高了模型的分类性能。  相似文献   

10.
针对命名实体识别方法存在字与字之间语义信息丢失、模型召回率不佳等问题,提出了一种跨度语义信息增强的命名实体识别方法。首先,使用ALBERT预训练语言模型提取文本中包含上下文信息的字符向量,并使用GloVe模型生成字符向量;其次,将两种向量进行拼接作为模型输入向量,对输入向量进行枚举拼接形成跨度信息矩阵;然后,使用多维循环神经网络和注意力网络对跨度信息矩阵进行运算,增强跨度之间的语义联系;最后,将跨度信息增强后的矩阵进行跨度分类以识别命名实体。实验表明:与传统的跨度方法相比该方法能够有效增强跨度之间的语义依赖特征,从而提升命名实体识别的召回率;该方法在ACE2005英文数据集上比传统的方法召回率提高了0.42%,并且取得了最高的F1值。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

18.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

19.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

20.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

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