Fault diagnosis(FD)for offshore wind turbines(WTs)are instrumental to their operation and maintenance(O&M).To improve the FD effect in the very early stage,a condition monitoring based sample set mining method fro...Fault diagnosis(FD)for offshore wind turbines(WTs)are instrumental to their operation and maintenance(O&M).To improve the FD effect in the very early stage,a condition monitoring based sample set mining method from supervisory control and data acquisition(SCADA)time-series data is proposed.Then,based on the convolutional neural network(CNN)and attention mechanism,an interpretable convolutional temporal-spatial attention network(CTSAN)model is proposed.The proposed CTSAN model can extract deep temporal-spatial features from SCADA time-series data sequentially by:(1)a convolution feature extraction module to extract features based on time intervals;(2)a spatial attention module to extract spatial features considering the weights of different features;and(3)a temporal attention module to extract temporal features considering the weights of intervals.The proposed CTSAN model has the superiority of interpretability by exposing the deep temporal-spatial features extracted in a human-understandable form of the temporal-spatial attention weights.The effectiveness and superiority of the proposed CTSAN model are verified by real offshore wind farms in China.展开更多
篇章要素识别(discourse element identification)的主要任务是识别篇章要素单元并进行分类.针对篇章要素识别对上下文依赖性理解不足的问题,提出一种基于BiLSTM-Attention的识别篇章要素模型,提高议论文篇章要素识别的准确率.该模型利...篇章要素识别(discourse element identification)的主要任务是识别篇章要素单元并进行分类.针对篇章要素识别对上下文依赖性理解不足的问题,提出一种基于BiLSTM-Attention的识别篇章要素模型,提高议论文篇章要素识别的准确率.该模型利用句子结构和位置编码来识别句子的成分关系,通过双向长短期记忆网络(bidirectional long short-term memory,BiLSTM)进一步获得深层次上下文相关联的信息;引入注意力机制(attention mechanism)优化模型特征向量,提高文本分类的准确度;最终用句间多头自注意力(multi-head self-attention)获取句子在内容和结构上的关系,弥补距离较远的句子依赖问题.相比于HBiLSTM、BERT等基线模型,在相同参数、相同实验条件下,中文数据集和英文数据集上准确率分别提升1.3%、3.6%,验证了该模型在篇章要素识别任务中的有效性.展开更多
交通运输业减排是实现全局减排目标的关键。研究基于改进的随机性环境影响评估(Stochastic Impacts by Regression on Population,Affluence,and Technology,STIRPAT)模型分析影响交通运输业碳排放的主要因素,设置低碳、基准和高碳3种...交通运输业减排是实现全局减排目标的关键。研究基于改进的随机性环境影响评估(Stochastic Impacts by Regression on Population,Affluence,and Technology,STIRPAT)模型分析影响交通运输业碳排放的主要因素,设置低碳、基准和高碳3种情景方案,利用卷积神经网络-长短期记忆网络-注意力机制(Convolutional Neural Networks-Long short-Term Memory-Attention Mec.hanism,CNN-LSTM-Attention)交通运输业碳排放预测模型对中国30个省、自治区、直辖市2022—2035年交通运输业碳排放进行预测。结果显示:人口情况、经济水平和交通运输等3个维度的影响因素对交通运输业碳排放具有正向驱动作用,能源技术维度的影响因素则起负向驱动作用;CNN-LSTM-Attention交通运输业碳排放预测模型提升了模型在小样本数据集的预测能力,预测效果较好;低碳、基准和高碳3种情景下中国交通运输业的碳排放峰值将晚于2030年的总排放峰值目标实现;各省在碳排放峰值和达峰时间上存在异质性,应采取差异化、精准化的政策策略,局部上分区域、分梯次达峰,以整体上实现碳达峰目标。展开更多
文摘Fault diagnosis(FD)for offshore wind turbines(WTs)are instrumental to their operation and maintenance(O&M).To improve the FD effect in the very early stage,a condition monitoring based sample set mining method from supervisory control and data acquisition(SCADA)time-series data is proposed.Then,based on the convolutional neural network(CNN)and attention mechanism,an interpretable convolutional temporal-spatial attention network(CTSAN)model is proposed.The proposed CTSAN model can extract deep temporal-spatial features from SCADA time-series data sequentially by:(1)a convolution feature extraction module to extract features based on time intervals;(2)a spatial attention module to extract spatial features considering the weights of different features;and(3)a temporal attention module to extract temporal features considering the weights of intervals.The proposed CTSAN model has the superiority of interpretability by exposing the deep temporal-spatial features extracted in a human-understandable form of the temporal-spatial attention weights.The effectiveness and superiority of the proposed CTSAN model are verified by real offshore wind farms in China.
文摘篇章要素识别(discourse element identification)的主要任务是识别篇章要素单元并进行分类.针对篇章要素识别对上下文依赖性理解不足的问题,提出一种基于BiLSTM-Attention的识别篇章要素模型,提高议论文篇章要素识别的准确率.该模型利用句子结构和位置编码来识别句子的成分关系,通过双向长短期记忆网络(bidirectional long short-term memory,BiLSTM)进一步获得深层次上下文相关联的信息;引入注意力机制(attention mechanism)优化模型特征向量,提高文本分类的准确度;最终用句间多头自注意力(multi-head self-attention)获取句子在内容和结构上的关系,弥补距离较远的句子依赖问题.相比于HBiLSTM、BERT等基线模型,在相同参数、相同实验条件下,中文数据集和英文数据集上准确率分别提升1.3%、3.6%,验证了该模型在篇章要素识别任务中的有效性.