针对基于立体视觉的移动机器人导航中摄像机视角及光线亮度的变化会使所获得的场景环境图像发生一定的仿射变换，为了选取稳定的图像局部特征点，提出了一种具有仿射不变的兴趣点检测算法——多项局部方向张量（polynomial local orient...针对基于立体视觉的移动机器人导航中摄像机视角及光线亮度的变化会使所获得的场景环境图像发生一定的仿射变换，为了选取稳定的图像局部特征点，提出了一种具有仿射不变的兴趣点检测算法——多项局部方向张量（polynomial local orientation tensors，PLOT）算子。PLOT算子是基于图像多项扩展式局部方向张量的兴趣点检测算法，它将图像的每一像素点以多项扩展式的方式展开建立局部图像信号模型，求其对应的局部方向张量，搜索局部方向张量最小特征值的局部邻域最大值，获得对图像兴趣点的初始检测定位，并应用仿射递归算法实现兴趣点及对应特征区域的最终准确检测与定位。基于重复率准则的兴趣点检测实验表明。展开更多
The stability of wall bounded fibre suspensions was studied. The linear stability analysis was performed applying the flow stability theory and slender body theory. The results of numerical analysis show that fibres...The stability of wall bounded fibre suspensions was studied. The linear stability analysis was performed applying the flow stability theory and slender body theory. The results of numerical analysis show that fibres and their hydrodynamic interactions reinforce the flow stability. Investigation of fibre orientation and vorticity in the suspension revealed the mechanisms behind the instability. Drag reduction properties in the transition regime were also presented. The experiments using dye emission and PIV techniques verified theoretical results.展开更多
文摘针对基于立体视觉的移动机器人导航中摄像机视角及光线亮度的变化会使所获得的场景环境图像发生一定的仿射变换，为了选取稳定的图像局部特征点，提出了一种具有仿射不变的兴趣点检测算法——多项局部方向张量（polynomial local orientation tensors，PLOT）算子。PLOT算子是基于图像多项扩展式局部方向张量的兴趣点检测算法，它将图像的每一像素点以多项扩展式的方式展开建立局部图像信号模型，求其对应的局部方向张量，搜索局部方向张量最小特征值的局部邻域最大值，获得对图像兴趣点的初始检测定位，并应用仿射递归算法实现兴趣点及对应特征区域的最终准确检测与定位。基于重复率准则的兴趣点检测实验表明。
文摘The stability of wall bounded fibre suspensions was studied. The linear stability analysis was performed applying the flow stability theory and slender body theory. The results of numerical analysis show that fibres and their hydrodynamic interactions reinforce the flow stability. Investigation of fibre orientation and vorticity in the suspension revealed the mechanisms behind the instability. Drag reduction properties in the transition regime were also presented. The experiments using dye emission and PIV techniques verified theoretical results.
