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The problem to identify the type of source generating discharges detected during campaigns of partial discharge (PD) measurements in cable terminal is of utmost importance in the quality control and state detection of the power supply system of a high-speed railway train. The purpose of this article is to provide a novel PD feature and a potential tool for cable terminal PD identification. The traditional PD type of high-speed train cable terminal is usually identified by PD test parameters, such as amplitude, PD times, and discharge energy. These features contain limited information and are easily affected by external factors, resulting in large numerical fluctuations, making the reliability of the test results low, which makes the operation, maintenance, and repair decision of high-speed train cables very difficult. Therefore, this article proposes a method that can extract rich feature information from PD data and distinguish PD types accurately and reliably by combining with a classification algorithm. First, to make full use of the characteristics of PD data, the single-scale PRPD images are transformed into multiscale PRPD images by using image pyramid theory. Then, the first-order texture statistics, the second-order texture statistics, and the higher order texture statistics are extracted from the multiscale PRPD space. Finally, the input features are optimized and classified by random forest and compared with other feature extraction algorithms. The results show that this method can identify PD type accurately and reliably, and the recognition accuracy is better than that of a single PD discharge feature.

Ethylene–propylene rubber (EPR) cable is the most commonly used type in high-speed railway. Several flashover accidents take place in cable termination in an extremely cold environment. In this study, EPR cable terminations were tested in a simulated low-temperature system with varied applied voltages. The results showed that the differences in elastic modulus and free space volume between EPR insulation and stress control tube (SCT) in a frigid environment would lead to structural defects between them. Damages on the EPR insulation occurred in the form of flashover point when the ambient temperature declined to −30°C and below, with the growth rate of discharge and resulting extent of damage across the EPR/SCT interface being non-linearly related to ambient temperature. Besides, the partial discharge (PD) initial voltage and PD extinction voltage under low-temperature conditions reduced by >40% compared with those at 20°C. The flashover probability of EPR terminations increased significantly, and the shape characteristics of PD patterns have also changed obviously at low temperatures. It can be verified that under the high-voltage and low-temperature conditions, the EPR/SCT interface is prone to organisational mismatch, which will lead to the PD phenomenon and seriously affect the stable operation of EPR cable terminations.

Osteoarthritis (OA), which is principally featured by progressive joint metabolic imbalance and subsequent degeneration of articular cartilage, is a common chronic joint disease. Arctigenin (ATG), a dietary phyto‐oestrogen, has been described to have potent anti‐inflammatory effects. Nevertheless, its protective effects on OA have not been clearly established. The target of our following study is to evaluate the protective effects of ATG on IL‐1β–induced human OA chondrocytes and mouse OA model. Our results revealed that the ATG pre‐treatment effectively decreases the level of pro‐inflammatory mediators, such as prostaglandin E2 (PGE2), nitrous oxide (NO), inducible nitric oxide synthase (iNOS), cyclooxygenase‐2 (COX‐2), IL‐6 and tumour necrosis factor alpha (TNF‐α) in IL‐1β–induced human chondrocytes. In addition, ATG protects against the degradation of extracellular matrix (ECM) under the stimulation of IL‐1β and the possible mechanism might be connected with the inactivation of phosphatidylinositol‐3‐kinase (PI3K)/Akt/nuclear factor‐kappa B (NF‐κB) axis. Furthermore, a powerful binding capacity between ATG and PI3K was also uncovered in our molecular docking research. Meanwhile, ATG may act as a protector on the mouse OA model. Collectively, all these findings suggest that ATG could be utilized as a promising therapeutic agent for the treatment of OA.