| Article ID: | iaor20165050 |
| Volume: | 33 |
| Issue: | 6 |
| Start Page Number: | 581 |
| End Page Number: | 591 |
| Publication Date: | Dec 2016 |
| Journal: | Expert Systems |
| Authors: | Li Qingguo, Zhang Rongrong, Li Zhaowen, Xie Ningxin |
| Keywords: | rough sets |
Rough set theory is a useful tool for dealing with imprecise knowledge. One of the advantages of rough set theory is the fact that an unknown target concept can be approximately characterized by existing knowledge structures in a knowledge base. This paper explores knowledge structures in a knowledge base. Knowledge structures in a knowledge base are firstly described by means of set vectors and relationships between knowledge structures divided into four classes. Then, properties of knowledge structures are discussed. Finally, group, lattice, mapping, and soft characterizations of knowledge structures are given.