现有的基于BERT(bidirectional encoder representations from transformers)的方面级情感分析模型仅使用BERT最后一层隐藏层的输出,忽略BERT中间隐藏层的语义信息,存在信息利用不充分的问题,提出一种融合BERT中间隐藏层的方面级情感分...现有的基于BERT(bidirectional encoder representations from transformers)的方面级情感分析模型仅使用BERT最后一层隐藏层的输出,忽略BERT中间隐藏层的语义信息,存在信息利用不充分的问题,提出一种融合BERT中间隐藏层的方面级情感分析模型。首先,将评论和方面信息拼接为句子对输入BERT模型,通过BERT的自注意力机制建立评论与方面信息的联系;其次,构建门控卷积网络(gated convolutional neural network,GCNN)对BERT所有隐藏层输出的词向量矩阵进行特征提取,并将提取的特征进行最大池化、拼接得到特征序列;然后,使用双向门控循环单元(bidirectional gated recurrent unit,BiGRU)网络对特征序列进行融合,编码BERT不同隐藏层的信息;最后,引入注意力机制,根据特征与方面信息的相关程度赋予权值。在公开的SemEval2014 Task4评论数据集上的实验结果表明:所提模型在准确率和F 1值两种评价指标上均优于BERT、CapsBERT(capsule BERT)、BERT-PT(BERT post train)、BERT-LSTM(BERT long and short-term memory)等对比模型,具有较好的情感分类效果。展开更多
Pattern recognition is critical to map data handling and their applications.This study presents a model that combines the Shape Context(SC)descriptor and Graph Convolutional Neural Network(GCNN)to classify the pattern...Pattern recognition is critical to map data handling and their applications.This study presents a model that combines the Shape Context(SC)descriptor and Graph Convolutional Neural Network(GCNN)to classify the patterns of interchanges,which are indispensable parts of urban road networks.In the SC-GCNN model,an interchange is modeled as a graph,wherein nodes and edges represent the interchange segments and their connections,respectively.Then,a novel SC descriptor is implemented to describe the contextual information of each interchange segment and serve as descriptive features of graph nodes.Finally,a GCNN is designed by combining graph convolution and pooling operations to process the constructed graphs and classify the interchange patterns.The SC-GCNN model was validated using interchange samples obtained from the road networks of 15 cities downloaded from OpenStreetMap.The classification accuracy was 87.06%,which was higher than that of the image-based AlexNet,GoogLeNet,and Random Forest models.展开更多
城市交通事故一般都发生在公共道路上,然而现有的交通事故风险预测算法都通过对预测区域进行规则网格化来确定预测空间单位,导致预测精度不高且实用价值较低。本文将道路路段作为预测单位,采用图卷积和长短期记忆网络,构建了一种基于路...城市交通事故一般都发生在公共道路上,然而现有的交通事故风险预测算法都通过对预测区域进行规则网格化来确定预测空间单位,导致预测精度不高且实用价值较低。本文将道路路段作为预测单位,采用图卷积和长短期记忆网络,构建了一种基于路网结构的城市交通事故短期风险预测方法(traffic accidents risk prediction based on road network,TARPBRN)。该方法能对指定路段短期内的交通事故风险进行预测,从而可以有针对性地进行治理,减少交通事故的发生。本文使用杭州市西湖区的交通事故数据对模型进行了训练,并与4种常用的计量经济学模型和3种已有的深度学习预测算法进行了对比。实验结果证明本文算法在准确度、正确率和漏报率等方面都优于已有算法。展开更多
文摘现有的基于BERT(bidirectional encoder representations from transformers)的方面级情感分析模型仅使用BERT最后一层隐藏层的输出,忽略BERT中间隐藏层的语义信息,存在信息利用不充分的问题,提出一种融合BERT中间隐藏层的方面级情感分析模型。首先,将评论和方面信息拼接为句子对输入BERT模型,通过BERT的自注意力机制建立评论与方面信息的联系;其次,构建门控卷积网络(gated convolutional neural network,GCNN)对BERT所有隐藏层输出的词向量矩阵进行特征提取,并将提取的特征进行最大池化、拼接得到特征序列;然后,使用双向门控循环单元(bidirectional gated recurrent unit,BiGRU)网络对特征序列进行融合,编码BERT不同隐藏层的信息;最后,引入注意力机制,根据特征与方面信息的相关程度赋予权值。在公开的SemEval2014 Task4评论数据集上的实验结果表明:所提模型在准确率和F 1值两种评价指标上均优于BERT、CapsBERT(capsule BERT)、BERT-PT(BERT post train)、BERT-LSTM(BERT long and short-term memory)等对比模型,具有较好的情感分类效果。
基金supported by the National Natural Science Foundation of China[grant numbers 42071450 and 42001415].
文摘Pattern recognition is critical to map data handling and their applications.This study presents a model that combines the Shape Context(SC)descriptor and Graph Convolutional Neural Network(GCNN)to classify the patterns of interchanges,which are indispensable parts of urban road networks.In the SC-GCNN model,an interchange is modeled as a graph,wherein nodes and edges represent the interchange segments and their connections,respectively.Then,a novel SC descriptor is implemented to describe the contextual information of each interchange segment and serve as descriptive features of graph nodes.Finally,a GCNN is designed by combining graph convolution and pooling operations to process the constructed graphs and classify the interchange patterns.The SC-GCNN model was validated using interchange samples obtained from the road networks of 15 cities downloaded from OpenStreetMap.The classification accuracy was 87.06%,which was higher than that of the image-based AlexNet,GoogLeNet,and Random Forest models.
文摘城市交通事故一般都发生在公共道路上,然而现有的交通事故风险预测算法都通过对预测区域进行规则网格化来确定预测空间单位,导致预测精度不高且实用价值较低。本文将道路路段作为预测单位,采用图卷积和长短期记忆网络,构建了一种基于路网结构的城市交通事故短期风险预测方法(traffic accidents risk prediction based on road network,TARPBRN)。该方法能对指定路段短期内的交通事故风险进行预测,从而可以有针对性地进行治理,减少交通事故的发生。本文使用杭州市西湖区的交通事故数据对模型进行了训练,并与4种常用的计量经济学模型和3种已有的深度学习预测算法进行了对比。实验结果证明本文算法在准确度、正确率和漏报率等方面都优于已有算法。
