特性关系粗糙集下属性值粗化细化时近似集增量更新方法研究

不完备信息系统是一般信息系统的推广,在现实中具有广泛的应用.信息系统动态变化时,对象的近似集会产生相应的变化.研究如何利用原有近似集信息来进行近似集的更新具有重要意义.信息系统动态变化主要可以从属性值粗化细化、属性集粗化细化、时象集粗化细化3个方面考虑.现仅讨论属性值粗化细化时近似集的增量更新方法,给出了不完备信息系统中属性值粗化细化的定义,讨论了在不完备信息系统下的特性关系粗糙集模型中属性值粗化细化时近似集的增量更新方法,并通过实例验证了方法的有效性.

Approaches for Incrementally Updating Approximations under Characteristic Relation-based Rough Sets While Attribute Values Coarsening and Refining

An incomplete information system is a generalization of an information system, which has wide applications in many domains. The approximations of concepts may vary when the information system is dynamically changing. It is meaningful to study how to update the approximations by using the original information. `hhe dynamic changes of information systems can be considered in the three aspects:the coarsening and refining of attribute valucs,the attribute set and the object set, This paper only focused on the approaches for updating approximations when coarsening and refining attribute values. The definitions of attribute values coarsening and refining in the incomplete information system were given. I}hen approaches for updating the approximations were discussed when coarsening and refining attribute values under the characteristic relation. Finally, several examples were given to illustrate the validity of the proposed approaches.