基于流向标量场与快速扫掠法的图像分割

通过将梯度向量流(Gradient vector flow,GVF)场与种子区域生长(Seeded region growing,SRG)法相结合,提出了一种快速的自动图像分割方法.首先基于梯度向量流场构建一个流向标量场,然后提出一种新型的快速种子区域生长分割法—快速扫掠法(Fast scanning method,FSM)对标量场进行初始分割,最后采用区域邻接图对初始分割结果进行区域合并得到最终结果.本方法分割速度快,如采用一个快速的梯度向量流算法,则可以用于实时应用.实验结果证实了本方法的高效与鲁棒.

Three-dimensional Spaces of Quasi-constant Curvature

In this paper some properties of three-dimensional spaces of quasi-constant curvature different from those of cases when dimension n≥4 are proved. In particular, two classes of non-conformally flat solutions of them are constructed. In physics,a three-dimensional space of quasi-constant curvature appears as the space-like hypersurface of the rotation-free cosmological model of type D for the fluids with heat flow in General Relativity.