对群中上近似的一个注记(英文)

Note on the upper rough approximation in a group

研究了群中子群的上近似和下近似的相关性质,指出并证明了其中3个关于上近似的性质中的包含关系实质是相等关系,从而改进了上近似的相关结论,为上近似的应用奠定了理论基础.

The paper studied about the properties of the lower and the upper approximations in a group, pointed out and proved that the inclusion symbols in three propositions about the upper approximation are really the equal-signs, which are very important in the theory of rough sets in a group.