contractible topological space是什么意思

用法例句

if X=Πσ∈ΣX σ is |Σ|paracompact,then X is shrinked(with B property or with D property) iff Πσ∈FX σ is shrinked (with B property or with D property) for  F∈[Σ] <ω ;2.

设X =Πσ∈ΣXσ是｜Σ｜ 仿紧空间 ,则X是可缩的 (具有B性质 ,D性质 )当且仅当 F∈ [Σ]<ω,Πσ∈FXσ 是可缩的 (具有B性质 ,D性质 ) ;2 。

The shrink quantity,theory value and test result of retaining roadways along goaf are the same,this shows the exantness of the mechanics model.

可缩量、理论值与现场沿空留巷试验测结果相同,说明了这种力学模型的正确性。

Preliminary study on the tubesheet shaft adaptive structure;

管板组合式井壁可缩结构的初步研究

The Acyclicity and Contractibility of Posets;

偏序集的零调性与可缩性

Theoretical research and in?situ observation shows the contractibility of the packing doesn′t suitable for the deformation characteristics of roof rocks.

理论及现场实测结果都表明 ,目前所用高水速凝材料的可缩性不能很好地适应巷道顶板运动特性 ,必须加以改