中文摘要：

论述了Rough集提出的意义、研究背景和发展趋势，分析了Rough集的实质是从一个不可定义的子集中，经等价关系构造出这个集合的上、下近似集，因而使得这个不可定义的集合转变为精确可定义的上、下近似集，从而在不可定义集上处理的问题可移到精确可定义的上、下近似集上去处理，这是Rough集创立的重大贡献．讨论了Rough集应用的广泛性及其在许多方面的应用实例，Rough集的应用，为粒计算研究提供了新思雏，促进了粒计算研究崛起．

英文摘要：

In the article, the significance, studying background, and the developing direction of the proposed Rough Sets are presented. Essentiality of ROugh Sets is analyzed, an undefinable set is transformed into accurate definable lower and upper approximations via equivalence relation. Hence the processing problems on the set may be removed to deal with them on the lower and upper approximations. This is a great contribution of proposed rough sets. The universality and successful examples of Rough Set applications are also discussed in the article. The successful applications of Rough Sets offer a new idea for studying granular computing, so the growing up of granular computing is speeded. Finally, theoretical significance and practice values are described in this article.