MR-YOLO: An Improved YOLOv5 Network for Detecting Magnetic Ring Surface Defects

Magnetic rings are widely used in automotive, home appliances, and consumer electronics. Due to the materials used, processing techniques, and other factors, there will be top cracks, internal cracks, adhesion, and other defects on individual magnetic rings during the manufacturing process. To find such defects, the most sophisticated YOLOv5 target identification algorithm is frequently utilized. However, it has problems such as high computation, sluggish detection, and a large model size. This work suggests an enhanced lightweight YOLOv5 (MR-YOLO) approach for the identification of magnetic ring surface defects to address these issues. To decrease the floating-point operation (FLOP) in the feature channel fusion process and enhance the performance of feature expression, the YOLOv5 neck network was added to the Mobilenetv3 module. To improve the robustness of the algorithm, a Mosaic data enhancement technique was applied. Moreover, in order to increase the network’s interest in minor defects, the SE attention module is inserted into the backbone network to replace the SPPF module with substantially more calculations. Finally, to further increase the new network’s accuracy and training speed, we substituted the original CIoU-Ioss for SIoU-Loss. According to the test, the FLOP and Params of the modified network model decreased by 59.4% and 47.9%, respectively; the reasoning speed increased by 16.6%, the model’s size decreased by 48.1%, and the mAP only lost by 0.3%. The effectiveness and superiority of this method are proved by an analysis and comparison of examples

Heat flux distribution with lower hybrid current drive in the experimental advanced superconducting tokamak

Lower hybrid current drive (LHCD) considerably affects the heat flux distribution. This study analyzed the lower divertor target plate (LDTP) with different LHCD powers and frequencies in the experimental advanced superconducting tokamak (EAST). The analysis provided a detailed explanation of the heat flux at specific times (i.e., transformation of magnetic field configuration, LHCD starting and operating periods) and specific target locations (i.e., original strike point and second peak heat flux area). The average heat flux, average peak heat flux, and maximum peak heat flux during operation of different LHCD powers and frequencies were determined and compared. The sizes of the heat fluxes at the specific target locations were compared at different LHCD powers and frequencies. In addition to the heat flux distribution under different LHCD powers and frequencies, the heat flux distributions in electron cyclotron resonance heating (ECRH) + LHCD and in LHCD only were investigated to study the effect of ECRH on heat flux distribution. Detailed analyses of the heat flux distribution under different conditions were conducted to provide a reference for actual engineering applications