Abstract: The extension of rough set model is one of the main contents of research about rough set. There have been many forms about the rough set model. The rough set model is developed greatly based on the cover. However, researchers mainly aimed at single universe to investigate, but the problems are often in many universes in real life, for example, the applications in medical diagnosis and so on. At the same time considering in the real life, the object of research is often uncertain, that is fuzzy. Based on the above considerations, this paper proposes a covering rough fuzzy set model over two universes and investigates the properties of the approximation operators.

Key words: two universes, rough set model, covering rough fuzzy sets

摘要： 粗糙集模型的扩展是粗糙集研究的主要内容之一，目前已经存在许多有关粗糙集模型的扩展形式。其中基于覆盖而建立的粗糙集模型得到了很大的发展，然而学者们主要是针对单个论域进行研究的，但是实际生活中的问题却往往是在多个论域上的，如在医疗诊断中的应用等。同时考虑到在实际生活中，研究的对象往往是不确定的，即带有模糊的。基于以上考虑，提出了在两个论域上的覆盖粗糙模糊集模型，并对近似算子的性质进行了研究。

关键词: 两个论域, 粗糙集模型, 覆盖粗糙模糊集