Research on bearing fault diagnosis method based on cjbm with semi-supervised and imbalanced data

Data-driven intelligent methods have been widely used in bearing fault diagnosis. However, it is observed that previous studies on bearing fault diagnosis always assume that the label samples are sufficient and that the number of normal and fault samples is the same or similar, which is challenging to meet in practical engineering applications. This assumption reduces the accuracy and stability of the semi-supervised imbalanced bearing data fault diagnosis model in practical working conditions. The complex training and weak interpretation problems of transfer learning methods are analyzed, and a center jumping boosting machine method for bearing intelligent fault recognition with semi-supervised and imbalanced data is proposed. First, a modified density peak clustering (DPC) algorithm is used to classify unlabeled samples and select subsamples, and aiming at the DPC problem, a gamma\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\gamma $$\end{document} DPC algorithm based on the gamma\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\gamma $$\end{document} jumping phenomenon is proposed to determine the number of clusters and intercept distance automatically. Second, combined with the synthetic minority oversampling technique, some minority class samples are added to achieve a balanced bearing dataset. Then, a few known faults are used to assign pseudo-labels to unknown samples. Finally, to diagnose the new data and reduce the amount of calculation in actual production, the balanced data after processing are used to train the bottom light gradient boosting machine model to solve intelligent classification and recognition of bearing vibration data. In addition, by using three bearing datasets with different balance ratios and comparing them with other methods, the superiority of the proposed method is verified in bearing condition identification.