本论文主要研究了图的最大亏格的下界问题以及有向图类在可定向曲面上嵌入的亏格分布。
In this paper, the lower bound problems of the maximum genus and the genus distributions of digraphs in orientable surfaces are studied.
我断言这条曲线，界定了另一个可定向的曲面。
Well, I claim this curve actually bounds another surface that is orientable.
引入积分绝对平均曲率来描述可定向闭曲面的平均弯曲程度。
Integral absolute mean curvature is introduced to describe average curving of an orientable closed surface.
应用推荐