Health monitor of bogie-bearing on the train can ensure constant operation of the rail transit system. Since the metro or other rail transit have high safety requirements, it is hard to acquire numerous fault samples. Besides, diagnosing train bogie-bearings under variable working conditions is challenging due to wheel-rail coupling, speed variation, and load fluctuation. An intelligent approach for bogie-bearing fault diagnosis is proposed to deal with the above problems. A third-order tensor model is established to be suitable for variable working conditions. Furthermore, a density-based affinity propagation tensor (DAP-Tensor) clustering algorithm is presented to identify different failures with unlabeled. Train bogie and public data sets were employed to simulate three probable conditions of train operation: high-frequency impact, speed variation, and load change. Compared with existing clustering methods in three cases, the proposed DAP-Tensor performs better in identifying bearing faults under variable working conditions. Moreover, The DAP-tensor has a comparable recognition rate to some deep learning methods, which unsupervised characteristics show it has potential for applications on rail transit trains.

Most existing visual question answering (VQA) models strongly rely on language bias to answer questions, i.e., they always tend to fit question-answer pairs on the train split and perform poorly on the test spilt when the answer distributions are different. This behavior makes them hard to be applied in real scenarios. To reduce the language biases, previous studies mainly integrate modules to overcome language priors (ensemble-based methods) or generate additional training data to balance dataset biases (data-balanced methods). However, all the existing ensemble-based methods drop their accuracies on the VQA v2 dataset, while data-balanced methods may introduce new biases and cannot guarantee the quality of the generated data. In this paper, we propose a model-agnostic training scheme called Suppressing Biased Samples (SBS) to overcome language priors. SBS consists of two collaborative parts, i.e., a Data Classifier Module to divide the dataset into biased samples and unbiased samples by utilizing the similarity in the semantic space, and a Bias Penalty Module to suppress the biased samples to weaken their influence. As a new way of balancing data to address language bias, SBS overcomes the shortcomings of previous data-balanced methods. Experimental results show that our method can be merged into other bias-reduction methods and achieves a new state-of-the-art performance on the commonly used VQA-CP v2 dataset.