More recently, wind speed forecasting as an effective computing technique currently plays an important role in advancing industry informatics, while dealing with those issues of control and operation for renewable power systems. However, it is facing some increasing difficulties to handle the large-scale dataset generated in these forecasting applications, with the purpose of ensuring stable computing performance. In response to such limitation, this article proposes a more practical approach through the combination of extreme learning machine (ELM) method and deep learning model. ELM as a novel computing paradigm enables the neural network- (NN-) based learning to be achieved with fast training speed and good generalization performance. The stacked ELM (SELM) is an advanced ELM algorithm under deep learning framework, which works efficiently on memory consumption decrease. In this article, an enhanced SELM is accordingly developed via replacing the Euclidean norm of the mean square error (MSE) criterion in ELM with the generalized correntropy criterion to further improve the forecasting performance. The advantage of the enhanced SELM with generalized correntropy to achieve better forecasting performance mainly relies on the following aspect. Generalized correntropy is a stable and robust nonlinear similarity measure while employing machine learning method to forecast wind speed, where the outliers may exist in some industrially measured values. Specifically, the experimental results of short-term and ultra-short-term forecasting on real wind speed data show that the proposed approach can achieve better computing performance compared with other traditional and more recent methods.

With the development of Internet of Things (IoT) technologies, more and more smart devices are connected to the Internet. Since these devices were designed for better connections with each other, very limited security mechanisms have been considered. It would be costly to develop separate security mechanisms for the diverse behaviors in different devices. Given new and changing devices and attacks, it would be helpful if the characteristics of diverse device types could be dynamically learned for better protection. In this paper, we propose a machine learning approach to device type identification through network traffic analysis for anomaly detection in IoT. Firstly, the characteristics of different device types are learned from their generated network packets using supervised learning methods. Secondly, by learning important features from selected device types, we further compare the effects of unsupervised learning methods including One-class SVM, Isolation forest, and autoencoders for dimensionality reduction. Finally, we evaluate the performance of anomaly detection by transfer learning with autoencoders. In our experiments on real data in the target factory, the best performance of device type identification can be achieved by XGBoost with an accuracy of 97.6%. When adopting autoencoders for learning features from the network packets in Modbus TCP protocol, the best F1 score of 98.36% can be achieved. Comparable performance of anomaly detection can be achieved when using autoencoders for transfer learning from the reference dataset in the literature to our target site. This shows the potential of the proposed approach for automatic anomaly detection in smart factories. Further investigation is needed to verify the proposed approach using different types of devices in different IoT environments.

In this paper, a novel method is developed for day-ahead daily river-flow forecasting based on convolutional neural network (CNN). The proposed method incorporates both spatial and temporal information to improve the forecasting performance. A CNN model is usually trained by minimizing the mean squared error which is, however, sensitive to few particularly large errors. This character of squared error loss function will result in a poor estimator. To tackle the problem, a robust loss function is proposed to train the CNN. To facilitate the training of CNNs for multiple sites forecasting, transfer learning is also applied in this study. With transfer learning, a new CNN inherits the structure and partial learnable parameters from a well-trained CNN to reduce the training complexity. The forecasting performance of the proposed method is validated with real data of four rivers by comparing with widely used benchmarking models including the autoregressive model, multilayer perception network, kernel ridge regression, radial basis function neural network, and generic CNN. Numerical results show that the proposed method performs best in terms of the root mean squared error, mean absolute error, and mean absolute percentage error. The two-sample Kolmogorov-Smirnov test is further applied to assess the confidence on the conclusion.