基于模型压缩与感受野增强的下茧实时检测

针对目前选茧时下茧检测主要依赖人工目测,工作效率低的问题,提出一种基于锚点框参数预置、通道剪枝和嵌入感受野模块改进的轻量化下茧实时检测模型。首先,通过K-means聚类分析出适用于下茧检测的锚点框以预置YOLOv3模型参数;然后,根据预设的剪枝率对稀疏化训练后的模型进行基于批量正则化层缩放因子的模型剪枝,以此压缩模型的大小;最后,在剪枝后的模型中嵌入感受野模块,使模型的感受野变大,增强模型的辨别能力和鲁棒性。实验结果表明:提出的下茧实时检测模型大小为46.90 M,平均检测速度达到50.18 帧/s,平均检测精度为96.80%,较原YOLOv3模型参数压缩了79.96%,平均检测速度提高了60.63%,平均检测精度提高了3.20%。     

Magnetic Second-Order Topological Insulator: An Experimentally Feasible 2D CrSiTe3

2D second-order topological insulators (SOTIs) have sparked significant interest, but currently, the proposed realistic 2D materials for SOTIs are limited to nonmagnetic systems. In this study, for the first time, a single layer of chalcogenide CrSiTe₃—an experimentally realized transition metal trichalcogenide is proposed with a layer structure—as a 2D ferromagnetic (FM) SOTI. Based on first-principles calculations, this study confirms that the CrSiTe₃ monolayer exhibits a nontrivial gapped bulk state in the spin-up channel and a trivial gapped bulk state in the spin-down channel. Based on the higher-order bulk–boundary correspondence, it demonstrates that the CrSiTe₃ monolayer exhibits topologically protected corner states with a quantized fractional charge ($\frac{e}{3}$) in the spin-up channel. Notably, unlike previous nonmagnetic examples, the topological corner states of the CrSiTe₃ monolayer are spin-polarized and pinned at the corners of the sample in real space. Furthermore, the CrSiTe₃ monolayer retains SOTI features when the spin–orbit coupling (SOC) is considered, as evidenced by the corner charge and corner states distribution. Finally, by applying biaxial strain and hole doping, this study transforms the magnetic insulating bulk states into spin-gapless semiconducting and half-metallic bulk states, respectively. Importantly, the topological corner states persist in the spin-up channel under these conditions.