Generalized textural rough sets: Rough set models over two universes

Local fuzzy rough set model over two universes and its reduction

“…Next, we will list some basic concepts of the fuzzy rough set models on two universes. For more details, please refer to [30,33,35].…”

“…Definition 2.6 [33] Let (U, V, R) be a fuzzy approximation space on two universes. For any Ỹ ∈ F(V), the θ-fuzzy lower approximation operator and the Tfuzzy upper approximation operator of Ỹ are defined as follows: for any x ∈ U,…”

“…In order to further improve the use of the model in continuous data and deal with some problems such as the fuzziness influence of a symptom on a disease, Li first extended the rough approximation operator on the two universes to fuzzy cases [31], and the fuzzy rough set models was considered on two universes [32] by Xu. Aysegui Altay also used norms to define upper and lower approximations [33]. Many scholars have applied this model to various fields, such as emergency material demand prediction and the analysis of the human body comfort [34][35][36][37].…”