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Multistep wind speed forecasting is of great significance for wind energy utilization. To further improve the performance of multistep wind speed forecasting, a new multistep forecasting strategy is proposed based on the basic wind speed multistep forecasting strategy and the corresponding forecasting system is established. The system consists of three parts, including a wavelet decomposition preprocessing module, nonlinear autoregressive artificial neural network and nonlinear autoregressive exogenous artificial neural network composite prediction module, and support vector machine classifier postprocessing module. The system analyzes historical wind speed data from two different angles to obtain dual time series features. Then, the double time series feature is used to improve the accuracy and stability of the multipart forecast. The predictive performance of the system is verified through two experiments. Experiment I tests the prediction accuracy and computing resource consumption of the system. Experiment II tests the stability of the system prediction under different wind conditions. The results show that, compared with the traditional multistep prediction strategy system, the new system has a better prediction accuracy and more stable prediction performance.

This paper explores the effects of wearable medical devices (WMDs) in vital sign monitoring, which is the key to telemedicine rehabilitation. First, 60 young patients were selected from the department of oral and maxillofacial surgery in a Chinese hospital. The vital signs of the patients, namely, ear temperature, pulse, blood oxygen saturation, and blood pressure, were measured by both the WMDs and the traditional devices. The measurements were carried out at 6:00, 10:00, 14:00, and 18:00 on the first day of each month in 2018. The comparison between the measured results shows that the WMDs and the traditional devices have no difference in the measured data and measurement time of any vital sign (P > 0.05), but the WMDs consumed much less time in data transcription and the entire measurement process. This means the WMDs are suitable for vital sign measurement in telemedicine rehabilitation.