针对偏最小二乘方法(partial least squares,PLS)在无量纲标准化处理后导致的特征值大小近似相等,难以获得代表性的潜变量等问题,提出了一种基于相对变换PLS(relative-transformation PLS,RTPLS)的故障检测方法。该方法引入马氏距离相...针对偏最小二乘方法(partial least squares,PLS)在无量纲标准化处理后导致的特征值大小近似相等,难以获得代表性的潜变量等问题,提出了一种基于相对变换PLS(relative-transformation PLS,RTPLS)的故障检测方法。该方法引入马氏距离相对变换理论,通过计算采样数据之间的马氏距离,将原始空间数据变换到相对空间。然后在相对空间进行PLS分解,提取有代表性的潜变量,建立故障检测模型,实现采样数据的在线检测。通过对TE(Tennessee Eastman)过程故障和轧钢机系统力传感器故障的仿真实验验证了所提出方法的有效性和实用性。理论分析和仿真实验均表明,基于RTPLS的故障检测方法能有效地消除量纲的影响,提取具有更大的变化度和代表性的隐变量,增加故障检测的精度和实时性。展开更多
In this paper the variation of interface stress intensity factors is considered under arbitrary material combinations for several problems such as central internal interface cracks,periodic interface cracks,and edge i...In this paper the variation of interface stress intensity factors is considered under arbitrary material combinations for several problems such as central internal interface cracks,periodic interface cracks,and edge interface cracks.The stress intensity factors for all these problems have been determined in terms of Dundurs' parameters,by the application of FEM in the authors' previous papers.In this paper,the variations of the stress intensity factors for all these problems are discussed under arbitrary,,then the maximum and minimum values of dimensionless stress intensity factors F I,max,F II,max,F I,min,F II,max are indicated on the map of,.As an example,it is found that F I,max always appears when(,)=(0.2,0.3),and F I,min always appears when(,)=(1,0),for the central internal interface cracks independent of crack length.展开更多
文摘针对偏最小二乘方法(partial least squares,PLS)在无量纲标准化处理后导致的特征值大小近似相等,难以获得代表性的潜变量等问题,提出了一种基于相对变换PLS(relative-transformation PLS,RTPLS)的故障检测方法。该方法引入马氏距离相对变换理论,通过计算采样数据之间的马氏距离,将原始空间数据变换到相对空间。然后在相对空间进行PLS分解,提取有代表性的潜变量,建立故障检测模型,实现采样数据的在线检测。通过对TE(Tennessee Eastman)过程故障和轧钢机系统力传感器故障的仿真实验验证了所提出方法的有效性和实用性。理论分析和仿真实验均表明,基于RTPLS的故障检测方法能有效地消除量纲的影响,提取具有更大的变化度和代表性的隐变量,增加故障检测的精度和实时性。
基金supported by the Japanese Government (Monbukagukusho) Scholarshipthe National Basic Research Program of China (Grant No.2011CB013702)
文摘In this paper the variation of interface stress intensity factors is considered under arbitrary material combinations for several problems such as central internal interface cracks,periodic interface cracks,and edge interface cracks.The stress intensity factors for all these problems have been determined in terms of Dundurs' parameters,by the application of FEM in the authors' previous papers.In this paper,the variations of the stress intensity factors for all these problems are discussed under arbitrary,,then the maximum and minimum values of dimensionless stress intensity factors F I,max,F II,max,F I,min,F II,max are indicated on the map of,.As an example,it is found that F I,max always appears when(,)=(0.2,0.3),and F I,min always appears when(,)=(1,0),for the central internal interface cracks independent of crack length.
