In this paper,we discuss when f(x) is a real valued function on E(ER 1),the sets of various discontinuous points of f(x) is or not is countable;when f(x) is semi continuous function,discontinuous points of f(x) is or not is countable.
给出当 f(x)是 E(E R1)上的实值有界半连续函数时 ,f(x)的不连续点是至多可数的 ,从而当 f(x)为强半连续函数时 ,则 f(x)取至多可数值。
English nouns can be practically classified into countable nouns and uncountable nouns.
英语名词可以从实用的角度分为可数名词及不可数名词。
In this paper, the concepts of twelve countable compactness in symmetric topological molecular lattices are introduced.
在对称拓扑分子格中引入12种可数紧性的概念,着重指出了它们在极不连通的对称拓扑分子格中的内在联系。
It follows from one of these characterizations that the pseudo open and compact image of a countably paracompact space is a countably metacompact space.
利用半开复盖、定向开复盖、单调递增开复盖、点态W 加细和垫状加细等刻画了可数亚紧性 。
Japanese mathematician Nobuyuki Kemoto proved that the product of two ordinals is hereditarily countably metacompact in 1996.
日本数学家NobuyukiKemoto在 1996年论证了两个序数的乘积是遗传可数亚紧空间 。
In a compact system, the limit set of a point can b e countable or uncountable.
紧空间上的动力系统中一点 x的极限集可能是可数的也可能是不可数的 。
The paper discusses Cantor s Diagonal Argument and the countability of set of real numbers based on the previous studies~().
在前期研究[2][3][4]的基础上,进一步讨论了康托对角线法及实数集的可数性问题,并给出了一个证明。
It is proved that separation Ti(i=-1,0,1,2) and countability CⅠ,CⅡ on symmetric topological molecular lattices are summable properties.
文章给出了对称拓扑分子格的直和概念,给出了拓扑分子格的直和的特征,证明了对称拓扑分子格的分离性Ti(i=-1,0,1,2)及可数性CⅠ,CⅡ是可和性质。