Ground-based interferometric synthetic aperture radar(GB-InSAR)can take deformation measurement with a high accuracy.Partition of the GB-InSAR deformation map benefits analyzing the deformation state of the monitoring...Ground-based interferometric synthetic aperture radar(GB-InSAR)can take deformation measurement with a high accuracy.Partition of the GB-InSAR deformation map benefits analyzing the deformation state of the monitoring scene better.Existing partition methods rely on labelled datasets or single deformation feature,and they cannot be effectively utilized in GBInSAR applications.This paper proposes an improved partition method of the GB-InSAR deformation map based on dynamic time warping(DTW)and k-means.The DTW similarities between a reference point and all the measurement points are calculated based on their time-series deformations.Then the DTW similarity and cumulative deformation are taken as two partition features.With the k-means algorithm and the score based on multi evaluation indexes,a deformation map can be partitioned into an appropriate number of classes.Experimental datasets of West Copper Mine are processed to validate the effectiveness of the proposed method,whose measurement points are divided into seven classes with a score of 0.3151.展开更多
The traditional grey incidence degree is mainly based on the distance analysis methods, which is measured by the displacement difference between corresponding points between sequences. When some data of sequences are ...The traditional grey incidence degree is mainly based on the distance analysis methods, which is measured by the displacement difference between corresponding points between sequences. When some data of sequences are missing (inconsistency in the length of the sequences), the only way is to delete the longer sequences or to fill the shorter sequences. Therefore, some uncertainty is introduced. To solve this problem, by introducing three-dimensional grey incidence degree (3D-GID), a novel GID based on the multidimensional dynamic time warping distance (MDDTW distance-GID) is proposed. On the basis of it, the corresponding grey incidence clustering (MDDTW distance-GIC) method is constructed. It not only has the simpler computation process, but also can be applied to the incidence comparison between uncertain multidimensional sequences directly. The experiment shows that MDDTW distance-GIC is more accurate when dealing with the uncertain sequences. Compared with the traditional GIC method, the precision of the MDDTW distance-GIC method has increased nearly 30%.展开更多
碰摩是转子系统中的一种常见故障。针对转子早期碰摩故障特征微弱难以提取的问题,在改进传统动态时间扭曲(Dynamic Time Warping,DTW)算法的基础上,提出一种基于角度权值的动态时间扭曲(Angle Weighted Dynamic Time Warping,AWDTW)算...碰摩是转子系统中的一种常见故障。针对转子早期碰摩故障特征微弱难以提取的问题,在改进传统动态时间扭曲(Dynamic Time Warping,DTW)算法的基础上,提出一种基于角度权值的动态时间扭曲(Angle Weighted Dynamic Time Warping,AWDTW)算法。在该算法中,通过识别不同时间序列的坐标向量之间的夹角,自动计算两时间序列中对应点的距离权值,并通过增加角度权值来改善传统DTW算法的不合理扭曲对齐,以此减少时间序列匹配时“奇点”的产生,从而提高时间序列的对齐精度。通过仿真数据和转子试验台碰摩振动数据来验证所提方法的有效性,同时,与传统DTW及其改进算法相比,所提方法因综合考虑坐标因素的影响,更有利于时间序列的对齐和相似性度量,从而能更有效凸显转子早期碰摩故障特征。展开更多
对装备中具体故障进行可诊断性评估,可以量化地表明故障被诊断的难易程度。针对故障可诊断性评价方法中存在的不客观及度量方法选择不恰当的问题,提出一种基于动态时间规整(Dynamic Time Warping,DTW)的时序距离度量方法。定义可诊断性...对装备中具体故障进行可诊断性评估,可以量化地表明故障被诊断的难易程度。针对故障可诊断性评价方法中存在的不客观及度量方法选择不恰当的问题,提出一种基于动态时间规整(Dynamic Time Warping,DTW)的时序距离度量方法。定义可诊断性评估模型,从实际系统中抽取系统的结构、信号、测试、故障模式4种要素,为故障可诊断性评估工作的开展打下基础。摒弃传统的从信号中提取特征进行相似性度量的做法,将信号看做时序序列,基于DTW方法衡量不同状态下各信号之间的相似程度,作为故障可诊断性的评估依据。使用动量轮系统对新方法进行仿真实验,仿真结果表明新方法在进行可诊断性评估方面具有客观性和有效性。展开更多
基金supported by the National Natural Science Foundation of China(61971037,61960206009,61601031)the Natural Science Foundation of Chongqing,China(cstc2020jcyj-msxm X0608,cstc2020jcyj-jq X0008)。
文摘Ground-based interferometric synthetic aperture radar(GB-InSAR)can take deformation measurement with a high accuracy.Partition of the GB-InSAR deformation map benefits analyzing the deformation state of the monitoring scene better.Existing partition methods rely on labelled datasets or single deformation feature,and they cannot be effectively utilized in GBInSAR applications.This paper proposes an improved partition method of the GB-InSAR deformation map based on dynamic time warping(DTW)and k-means.The DTW similarities between a reference point and all the measurement points are calculated based on their time-series deformations.Then the DTW similarity and cumulative deformation are taken as two partition features.With the k-means algorithm and the score based on multi evaluation indexes,a deformation map can be partitioned into an appropriate number of classes.Experimental datasets of West Copper Mine are processed to validate the effectiveness of the proposed method,whose measurement points are divided into seven classes with a score of 0.3151.
基金supported by the National Natural Science Foundation of China(6153302061309014)the Natural Science Foundation Project of CQ CSTC(cstc2017jcyj AX0408)
文摘The traditional grey incidence degree is mainly based on the distance analysis methods, which is measured by the displacement difference between corresponding points between sequences. When some data of sequences are missing (inconsistency in the length of the sequences), the only way is to delete the longer sequences or to fill the shorter sequences. Therefore, some uncertainty is introduced. To solve this problem, by introducing three-dimensional grey incidence degree (3D-GID), a novel GID based on the multidimensional dynamic time warping distance (MDDTW distance-GID) is proposed. On the basis of it, the corresponding grey incidence clustering (MDDTW distance-GIC) method is constructed. It not only has the simpler computation process, but also can be applied to the incidence comparison between uncertain multidimensional sequences directly. The experiment shows that MDDTW distance-GIC is more accurate when dealing with the uncertain sequences. Compared with the traditional GIC method, the precision of the MDDTW distance-GIC method has increased nearly 30%.
文摘碰摩是转子系统中的一种常见故障。针对转子早期碰摩故障特征微弱难以提取的问题,在改进传统动态时间扭曲(Dynamic Time Warping,DTW)算法的基础上,提出一种基于角度权值的动态时间扭曲(Angle Weighted Dynamic Time Warping,AWDTW)算法。在该算法中,通过识别不同时间序列的坐标向量之间的夹角,自动计算两时间序列中对应点的距离权值,并通过增加角度权值来改善传统DTW算法的不合理扭曲对齐,以此减少时间序列匹配时“奇点”的产生,从而提高时间序列的对齐精度。通过仿真数据和转子试验台碰摩振动数据来验证所提方法的有效性,同时,与传统DTW及其改进算法相比,所提方法因综合考虑坐标因素的影响,更有利于时间序列的对齐和相似性度量,从而能更有效凸显转子早期碰摩故障特征。
文摘对装备中具体故障进行可诊断性评估,可以量化地表明故障被诊断的难易程度。针对故障可诊断性评价方法中存在的不客观及度量方法选择不恰当的问题,提出一种基于动态时间规整(Dynamic Time Warping,DTW)的时序距离度量方法。定义可诊断性评估模型,从实际系统中抽取系统的结构、信号、测试、故障模式4种要素,为故障可诊断性评估工作的开展打下基础。摒弃传统的从信号中提取特征进行相似性度量的做法,将信号看做时序序列,基于DTW方法衡量不同状态下各信号之间的相似程度,作为故障可诊断性的评估依据。使用动量轮系统对新方法进行仿真实验,仿真结果表明新方法在进行可诊断性评估方面具有客观性和有效性。
