从无人机视角进行目标检测,面临图像目标小、分布密集、类别不均衡等难点,且由于无人机的硬件条件限制了模型的规模,导致模型的准确率偏低。提出一种融合多种注意力机制的YOLOv8s改进模型,在骨干网络中引入感受野注意力卷积和CBAM(conce...从无人机视角进行目标检测,面临图像目标小、分布密集、类别不均衡等难点,且由于无人机的硬件条件限制了模型的规模,导致模型的准确率偏低。提出一种融合多种注意力机制的YOLOv8s改进模型,在骨干网络中引入感受野注意力卷积和CBAM(concentration-based attention module)注意力机制改进卷积模块,解决注意力权重参数在感受野特征中共享问题的同时,在通道和空间维度加上注意力权重,增强特征提取能力;通过引入大型可分离卷积注意力思想,改造空间金字塔池化层,增加不同层级特征间的信息交融;优化颈部结构,增加具有丰富小目标语义信息的特征层;使用inner-IoU损失函数的思想改进MPDIoU(minimum point distance based IoU)函数,以innerMPDIoU代替原损失函数,提升对困难样本的学习能力。实验结果表明,改进后的YOLOv8s模型在VisDrone数据集上mAP、P、R分别提升了16.1%、9.3%、14.9%,性能超过YOLOv8m,可以有效应用于无人机平台上的目标检测任务。展开更多
Gamma/delta T cells (γδТ cells) are among the first lymphoid cells appearing in the ontogenesis. Many of γδТ cells are located in the small intestine/lamina propria of mice and human, where they cooperate with d...Gamma/delta T cells (γδТ cells) are among the first lymphoid cells appearing in the ontogenesis. Many of γδТ cells are located in the small intestine/lamina propria of mice and human, where they cooperate with different cells (B-1 cells, in particular) and influence their activity. However, such interactions are studied rather scanty, and the functional role of γδТ cells in the intestine?is not yet fully elucidated. To study the interactions of mouse γδТ cells with other cells it is necessary to have purified cell populations. Unfortunately, most approaches used for isolation of human γδТ cells are not suitable for isolation of mouse γδТ cells. The aim of the present study is the modification of the method of mouse intestinal γδТ cell isolation in the quantities sufficient for the in vivo and in vitro experiments.展开更多
文摘从无人机视角进行目标检测,面临图像目标小、分布密集、类别不均衡等难点,且由于无人机的硬件条件限制了模型的规模,导致模型的准确率偏低。提出一种融合多种注意力机制的YOLOv8s改进模型,在骨干网络中引入感受野注意力卷积和CBAM(concentration-based attention module)注意力机制改进卷积模块,解决注意力权重参数在感受野特征中共享问题的同时,在通道和空间维度加上注意力权重,增强特征提取能力;通过引入大型可分离卷积注意力思想,改造空间金字塔池化层,增加不同层级特征间的信息交融;优化颈部结构,增加具有丰富小目标语义信息的特征层;使用inner-IoU损失函数的思想改进MPDIoU(minimum point distance based IoU)函数,以innerMPDIoU代替原损失函数,提升对困难样本的学习能力。实验结果表明,改进后的YOLOv8s模型在VisDrone数据集上mAP、P、R分别提升了16.1%、9.3%、14.9%,性能超过YOLOv8m,可以有效应用于无人机平台上的目标检测任务。
文摘Gamma/delta T cells (γδТ cells) are among the first lymphoid cells appearing in the ontogenesis. Many of γδТ cells are located in the small intestine/lamina propria of mice and human, where they cooperate with different cells (B-1 cells, in particular) and influence their activity. However, such interactions are studied rather scanty, and the functional role of γδТ cells in the intestine?is not yet fully elucidated. To study the interactions of mouse γδТ cells with other cells it is necessary to have purified cell populations. Unfortunately, most approaches used for isolation of human γδТ cells are not suitable for isolation of mouse γδТ cells. The aim of the present study is the modification of the method of mouse intestinal γδТ cell isolation in the quantities sufficient for the in vivo and in vitro experiments.
