weak retract是什么意思

用法例句

Retracts and Semiretracts of Topological Spaces;

拓扑空间的收缩核与半收缩核(英)

In this paper the topological properties of solution set of non-autonomous differential inclusions are discussed,and the fact that the mild solution set of Cauchy is a retract of a convex subset of a Banach space is proved.

讨论了半线性微分包含解的拓扑性质,证明了非自治情况下其适度解集是一Banach空间的凸子集的收缩核,且收缩映射连续依赖于初值。

By applying retract in normed linear spaces,we give in this papera fixed point theorem of domain compression and expansion of convex functional type,and extend Guo s theorem.

利用赋范线性空间中的收缩核,给出了凸泛函型的区域压缩与拉伸不动点定理,推广了郭大钧定理。

On a Class of Retractions in LCS;

关于LCS中的一类保核收缩

Some interesting new informations about them are obtained as following:(1)In a connected category, the morphisms whose domains (codomains) are initial objects, terminal objects or zero objects are all sections (retractions).

主要结果有：（１） 在连通范畴中，以始对象或终对象或零对象为定义域（ 取值域） 的态射皆为截片（ 保核收缩） 。