DS-rough set in Object-oriented Data Base System and its application

In Object-Oriented Data Base (OODB), attributions and methods are encapsulated together to form class and the instances of class form object. Affected by methods, the attribute values of the object are changing constantly settling in or moving out of the sets. The object sets being studied become bidirectional DS-sets. By analyzing the characteristic of class and S-rough set, the object-oriented DS-rough set which based on the dynamic characteristic is defined. DS-rough set has the encapsulation and concealment characteristic of class, which is the general form and the further expansion of S-rough set and rough set. By the end of the paper, the application of DS-rough set in Object-Oriented Data Base (OODB) has been explained by a simple example