... Rough Knowledge Base System. The system tackles two problems not fully answered by previous research: the ability to define rough sets in terms of other rough sets and incorporation of domain or expert knowledge. We describe two main ...

... Rough Knowledge Base System. The system tackles two problems not fully answered by previous research: the ability to define rough sets in terms of other rough sets and incorporation of domain or expert knowledge. We describe two main ...

... define and to reason about rough sets. In particular we show how to test for rough inclusion and rough equality. This extension to our previous work [7] is motivated by the need of these concepts in practical applications. Keywords: Rough ...

... define rough set concepts such as indiscernibility, definability and set approximations in terms of axioms. We prove that, in thecase of complete in- formation systems, the proposed approach is equivalent to the approach used so far in ...

... define rough approximations of unions X and X , which is described in the next section . 3 Variable Consistency Model of DRSA One of the most important features of rough set approach is separation of certain and possible knowledge . In ...

... rough set theory is the approximation of a subset of U by using the family of equivalence classes U/E = {[x] | x ∈ U}. There exist two formulations for defining rough set approximations of a subset of objects X ⊆ U. One way to define rough ...

... defining and querying rough relations , called Rough Data- log . As a matter of fact , the decision systems can also be encoded in Rough Datalog . Thus , we can define rough relations from scratch . This section introduces the language ...

... rough inclusion functions , membership , and quality of approximation functions [ 7,29 ] can be used to define CRRF2s . An example is the function ¿ 5 defined by E5 ( a , b ) = Card ( ba ) Card ( b ) ( 1 ) 5.2 Formalizing the BKM ...

... define dual relative pseudocomplement . Hence completely distributive lattices are bi - Heyting algebras . Definition 7. Let L be a complete lattice and a be an element of L. Then a is called ... Defining Rough Approximations 123.

... rough sets have SET as their ' base ' category , we see that the categories of rough sets can indeed be lifted to such a general setting using elementary topos . We define a category RSC ( C ) , where is an arbitrary non - degenerate ...