不完备目标信息系统中基于差异关系的粗糙集  

Discernibility Relation-based Rough Set in Incomplete Decision System

作　　者：魏利华[1,3] 唐振民[1] 丁辉[1,2] 吴刚[1] 

机构地区：[1]南京理工大学计算机科学与技术学院,江苏南京210094 [2]嘉兴学院数学与信息工程学院,浙江嘉兴314001 [3]德雷塞尔大学信息科学与技术学院,美国费城PA19104

出　　处：《南京理工大学学报》2010年第4期415-419,共5页Journal of Nanjing University of Science and Technology

基　　金：浙江省自然科学基金(Y1090649);浙江省教育厅科研计划项目(Y200805349)

摘　　要：针对建立在等价关系上的传统粗糙集对差异关系研究不足的情况,基于差异关系对传统粗糙集模型进行了扩展。在不完备目标信息系统中定义差异关系并基于这种差异关系扩充粗糙集模型。等价关系反映事物共性,差异关系反映事物个性,基于差异关系的粗糙集可用于约简否定规则。文中定义了一种差异关系,证明了基于差异关系的下、上近似集的主要性质,建立了相应的近似约简模型,最后给出了近似约简的判定定理和计算方法。Considering discernibility that the classical rough set approach based on indiscernibility relation rarely concerns discernibility relation,the classical rough set model is extended on the basis of discernibility relation.A discernibility relation-based rough set theory is further advanced for incomplete decision system in this paper.Indiscernibility relation reflects the commonness of things while discernibility relation displays individuality between them and the rough set model based on discernibility relation can be used to simplify negative rules.In this paper,a new discernibility relation is defined and the main properties of the lower and upper approximations are verified based on the discernibility relation before the construction of the new rough set model.The corresponding judging theorem and computing process for approximation reducts are thereby advanced.

关 键 词：不完备目标信息系统 等价关系 差异关系 下近似集 上近似集 近似约简 

分 类 号：TP18[自动化与计算机技术—控制理论与控制工程]