Deep learning has made significant strides in fault diagnosis when training and testing are conducted within domains of the same distribution. However, data collected from actual industrial equipment often originates from varying load operating conditions, leading to shifts in the manifestation of fault patterns. Additionally, non-stationary signals tend to exhibit similarities or weak fault frequencies in the frequency domain, making them difficult to distinguish. To address these problems, a prototypical normalized output domain adversarial adaptation network (PNOAN) with local and full frequency fusion perception is proposed. Initially, the vibration signal is transformed to time frequency graph by Morlet wavelet. Then, a band pooling module is employed to learn the long-range local context of axial time and frequency in time frequency graph to achieve local perception of fault signal, while a dual-part attention mechanism focuses on both high and low frequency information to achieve full frequency perception. Furthermore, an improved domain adversarial neural network is designed to standardize the conditional alignment of features and prediction probabilities for domain adaption fault diagnosis. Extensive results on a rotating bearing dataset illustrate the effectiveness and superiority of the proposed PNOAN.

Industrial time series prediction (ITSP) is critical to the predictive maintenance system of modern industry. However, time-varying conditions and complex industrial processes cause the distribution drift of industrial time series, raising the difficulty of prediction. This article proposes an ITSP model considering distribution information, namely MDEformer. First, the multivariate dynamic embedding (MDE) is designed to provide the property of the channel-binding dynamic distribution awareness. Specifically, a dynamic mode transition and selection module is adopted to exploit dynamic distribution features of time series, and the bidirectional dynamic residual connection integrates dynamic distribution information into embedding vectors to filter distribution change interference. Then, the vanilla Transformer encoder is used to achieve multivariate prediction. Finally, a generative pretraining and fine-tuning strategy is used to enhance the generalization ability in real production scenarios. Extensive results on a real-world zinc smelting dataset illustrate the superiority of MDEformer.

Recently, zero-shot fault diagnosis has gradually attracted the attention of researchers because that some type of data cannot be obtained in advance in practical production scenarios. However, the existing zero-shot methods hardly utilize multi-channel data information and learn the potential correlation between signal patches and attributes for unseen fault classes, resulting in unsatisfactory diagnostic accuracy. To address these issues, we propose a patch-attribute alignment method based on channel-time attention for zero-shot fault diagnosis. First, a feature extraction module with channel attention is introduced to obtain the multi-channel information of signal patch. Then the feature map and the corresponding attribute vector are processed interactively by an embedding-reconstruction structure. Finally, a patch-attribute alignment module with time attention CNN is utilized to predict the attribute vector and consequently obtain the corresponding fault diagnosis label. Extensive experiments show that the proposed method outperforms baseline zero-shot fault diagnosis methods, and ablation experiments demonstrate the effectiveness of each module.

As one of the most important artificial intelligence-enabled industrial applications, fault diagnosis is vital in the safe, stable, and reliable operation of the equipment. Many existing deep learning-based fault diagnosis methods assume that the distribution of training data is the same as that of testing data, which is almost impossible in practical industrial applications. In addition, most of these fault diagnosis methods are generally memory-intensive and computationally expensive. A compressed unsupervised deep domain adaption model-based fault diagnosis method is proposed to overcome the abovementioned two issues. First, a standard unsupervised domain adaption model is designed to extract the features of training data and testing data, respectively. Then, the maximum mean discrepancy term is introduced to minimize the discrepancy between the extracted features of them. Next, the standard model is compressed through iteratively pruning the redundant convolutional channels. Finally, the obtained compressed model is applied to diagnose faults. The performance of the proposed method is verified on the Case Western Reserve University bearing dataset. Experimental results show that the compressed model can significantly reduce the memory occupation, computational cost, and inference time compared with the standard model, but still achieve comparable or even better accuracy on ten transfer diagnostic tasks.

Recently, coronary heart disease has attracted more and more attention, where segmentation and analysis for vascular lumen contour are helpful for treatment. And intravascular optical coherence tomography (IVOCT) images are used to display lumen shapes in clinic. Thus, an automatic segmentation method for IVOCT lumen contour is necessary to reduce the doctors' workload while ensuring diagnostic accuracy. In this paper, we proposed a deep residual segmentation network of multi-scale feature fusion based on attention mechanism (RSM-Network, Residual Squeezed Multi-Scale Network) to segment the lumen contour in IVOCT images. Firstly, three different data augmentation methods including mirror level turnover, rotation and vertical flip are considered to expand the training set. Then in the proposed RSM-Network, U-Net is contained as the main body, considering its characteristic of accepting input images with any sizes. Meanwhile, the combination of residual network and attention mechanism is applied to improve the ability of global feature extraction and solve the vanishing gradient problem. Moreover, the pyramid feature extraction structure is introduced to enhance the learning ability for multi-scale features. Finally, in order to increase the matching degree between the actual output and expected output, the cross entropy loss function is also used. A series of metrics are presented to evaluate the performance of our proposed network and the experimental results demonstrate that the proposed RSM-Network can learn the contour details better, contributing to strong robustness and accuracy for IVOCT lumen contour segmentation.

At present, the application of Electroencephalogram (EEG) signal classification to human intention-behavior prediction has become a hot topic in the brain computer interface (BCI) research field. In recent studies, the introduction of convolutional neural networks (CNN) has contributed to substantial improvements in the EEG signal classification performance. However, there is still a key challenge with the existing CNN-based EEG signal classification methods, the accuracy of them is not very satisfying. This is because most of the existing methods only utilize the feature maps in the last layer of CNN for EEG signal classification, which might miss some local and detailed information for accurate classification. To address this challenge, this paper proposes a multi-scale CNN model-based EEG signal classification method. In this method, first, the EEG signals are preprocessed and converted to time-frequency images using the short-time Fourier Transform (STFT) technique. Then, a multi-scale CNN model is designed for EEG signal classification, which takes the converted time-frequency image as the input. Especially, in the designed multi-scale CNN model, both the local and global information is taken into consideration. The performance of the proposed method is verified on the benchmark data set 2b used in the BCI contest IV. The experimental results show that the average accuracy of the proposed method is 73.9 percent, which improves the classification accuracy of 10.4, 5.5, 16.2 percent compared with the traditional methods including artificial neural network, support vector machine, and stacked auto-encoder.

Aortic stent has been widely used in restoring vascular stenosis and assisting patients with cardiovascular disease. The effective visualization of aortic stent is considered to be critical to ensure the effectiveness and functions of the aortic stent in clinical practice. Volume rendering with ray casting has been used as an effective approach to enable the effective visualization of aortic stent. The volume rendering relies on the transfer function that converts the medical images into optical attributes including color and transparency. This article proposes a new transfer function, namely, the multi-dimensional transfer function, to provide additional transparency value of a voxel. The proposed approach using the additional transparency value effectively assists the distinguishing of tissues that have the same CT value. The transparency values are simultaneously determined by gray threshold and gray change threshold, which can recognize the unnecessary structures such as bones transparent. A series of experimental results demonstrate that the situation of aorta stent of a patient can be directly observed, and the angle of view can be switched arbitrarily. The proposed method provides a new way for the operation of a virtual endoscopy to reach the place of blood vessels that a traditional endoscopy fails to reach.

We introduce RFixer, a tool for repairing complex regular expressions using examples and only consider regular expressions without non-regular operators (e.g., negative lookahead). Given an incorrect regular expression and sets of positive and negative examples, RFixer synthesizes the closest regular expression to the original one that is consistent with the examples. Automatically repairing regular expressions requires exploring a large search space because practical regular expressions: i) are large, ii) operate over very large alphabets---e.g., UTF-16 and ASCII---and iii) employ complex constructs---e.g., character classes and numerical quantifiers. RFixer's repair algorithm achieves scalability by taking advantage of structural properties of regular expressions to effectively prune the search space, and it employs satisfiability modulo theory solvers to efficiently and symbolically explore the sets of possible character classes and numerical quantifiers. RFixer could successfully compute minimal repairs for regular expressions collected from a variety of sources, whereas existing tools either failed to produce any repair or produced overly complex repairs.

In order to make the smart home system to have the ability of learning user behavior actively and provide services spontaneously, this paper introduced user behavior prediction model which combined back propagation neural network (BPNN) with Hadoop parallel computing to the traditional smart home system, numerous user-generated behavior and environmental parameters data are packaged in particular data frame format and uploaded to the cloud platform through 4G or WLAN by the home gateway. According to the received historical data, repeated parallel training of BPNN which run on cloud platform was utilized to achieve user behavior prediction. Case study on smart home validated that the proposed model is valid for user behavior prediction with accuracy elevated, it can help user to complete equipment operating independently in the corresponding cases. Another comparison, time efficiency experiment on the parallelized neural network algorithm also showed that the suggested method is excellent in convergence speed and accuracy.

This letter proposes a novel 1.5-D algorithm for multi-channel electroencephalogram (EEG) compression. The proposed algorithm only needs to perform 1-D Discrete Wavelet Transform (DWT) rather than the 2-D version employed by previous works, and thus it results in lower computational complexity and power dissipation. In this algorithm, a new 2-D arranging method that exploits correlations between different sub-bands is developed to concentrate the energy, which causes more efficient compression using No List Set Partitioning in Hierarchical Trees (NLSPIHT) algorithm. Experimental results demonstrate that the proposed algorithm outperforms 2-D NLSPIHT algorithm under the same compression ratio (CR) and it is slightly inferior to 2-D SPIHT algorithm in the near-lossless compression regime, but it can provide a better fidelity with respect to higher CRs.