The core is a set which satisfies a system of weak linear inequalities, so it is closed and convex.
中心是一个满足弱线性不等式的合集,因此它是封闭的、凸的。
2
Based on geometry and convexset methods, this paper gives systemically the definitions of global and local convexity for planar closed parametric curve, and proves the two definitions are equivalent.
从几何和凸集的角度,系统地给出了平面闭参数曲线全局凸和局部凸定义,并且证明了这两个定义是等价的。
3
It is obtained that a necessary and sufficient condition for a closed fuzzy set to be a convex fuzzy set.