关键词: 两个论域, 粗糙集模型, 覆盖粗糙模糊集

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