Accurate fault root cause diagnosis is essential for ensuring stable industrial production. Traditional methods, which typically rely on the entire time series and overlook critical local features, can lead to biased ...Accurate fault root cause diagnosis is essential for ensuring stable industrial production. Traditional methods, which typically rely on the entire time series and overlook critical local features, can lead to biased inferences about causal relationships, thus hindering the accurate identification of root cause variables. This study proposed a shapelet-based state evolution graph for fault root cause diagnosis (SEG-RCD), which enables causal inference through the analysis of the important local features. First, the regularized autoencoder and fault contribution plot are used to identify the fault onset time and candidate root cause variables, respectively. Then, the most representative shapelets were extracted to construct a state evolution graph. Finally, the propagation path was extracted based on fault unit shapelets to pinpoint the fault root cause variable. The SEG-RCD can reduce the interference of noncausal information, enhancing the accuracy and interpretability of fault root cause diagnosis. The superiority of the proposed SEG-RCD was verified through experiments on a simulated penicillin fermentation process and an actual one.展开更多
针对基于shapelets转换的时间序列分类方法中候选shapelets存在较大相似性的问题,提出一种基于多样化top-k shapelets转换的分类方法 Div Top KShapelet。该方法采用多样化top-k查询技术,去除相似shapelets,并筛选出最具代表性的k个shap...针对基于shapelets转换的时间序列分类方法中候选shapelets存在较大相似性的问题,提出一种基于多样化top-k shapelets转换的分类方法 Div Top KShapelet。该方法采用多样化top-k查询技术,去除相似shapelets,并筛选出最具代表性的k个shapelets集合,最后以最优shapelets集合为特征对数据集进行转换,达到提高分类准确率及时间效率的目的。实验结果表明,Div Top KShapelet分类方法不仅比传统分类方法具有更高的准确率,而且与使用聚类筛选的方法(Cluster Shapelet)和shapelets覆盖的方法(Shapelet Selection)相比,分类准确率最多提高了48.43%和32.61%;同时在所有15个数据集上均有计算效率的提升,最少加速了1.09倍,最高可达到287.8倍。展开更多
基金support from the following foundations:the National Natural Science Foundation of China(62322309,62433004)Shanghai Science and Technology Innovation Action Plan(23S41900500)Shanghai Pilot Program for Basic Research(22TQ1400100-16).
文摘Accurate fault root cause diagnosis is essential for ensuring stable industrial production. Traditional methods, which typically rely on the entire time series and overlook critical local features, can lead to biased inferences about causal relationships, thus hindering the accurate identification of root cause variables. This study proposed a shapelet-based state evolution graph for fault root cause diagnosis (SEG-RCD), which enables causal inference through the analysis of the important local features. First, the regularized autoencoder and fault contribution plot are used to identify the fault onset time and candidate root cause variables, respectively. Then, the most representative shapelets were extracted to construct a state evolution graph. Finally, the propagation path was extracted based on fault unit shapelets to pinpoint the fault root cause variable. The SEG-RCD can reduce the interference of noncausal information, enhancing the accuracy and interpretability of fault root cause diagnosis. The superiority of the proposed SEG-RCD was verified through experiments on a simulated penicillin fermentation process and an actual one.
文摘针对基于shapelets转换的时间序列分类方法中候选shapelets存在较大相似性的问题,提出一种基于多样化top-k shapelets转换的分类方法 Div Top KShapelet。该方法采用多样化top-k查询技术,去除相似shapelets,并筛选出最具代表性的k个shapelets集合,最后以最优shapelets集合为特征对数据集进行转换,达到提高分类准确率及时间效率的目的。实验结果表明,Div Top KShapelet分类方法不仅比传统分类方法具有更高的准确率,而且与使用聚类筛选的方法(Cluster Shapelet)和shapelets覆盖的方法(Shapelet Selection)相比,分类准确率最多提高了48.43%和32.61%;同时在所有15个数据集上均有计算效率的提升,最少加速了1.09倍,最高可达到287.8倍。
