属性约简中的范式转换算法研究  

ON NORMAL FORM CONVERSION ALGORITHM IN ATTRIBUTE REDUCTION

作　　者：俞雪平[1,2] 胡云安[3] 

机构地区：[1]海军航空工程学院研究生管理大队 [2]92914部队 [3]海军航空工程学院控制工程系

出　　处：《计算机应用与软件》2015年第1期271-274,共4页Computer Applications and Software

摘　　要：通过研究属性约简中合取范式到析取范式的转换过程,发现减少冗余项和重复计算可以适当提高转换效率。同时考虑到范式的动态变化,设计一种边转换边化简的增量转换算法,可以利用已有结果直接进行计算。对于减量情况,抽象出范式转换的数学模型,给出相应转换的构造形式和分析过程,并提出一种近似减量转换算法,从而实现了不同变化情况下生成析取范式的动态计算。最后通过仿真实验验证了算法的可行性和高效性。By studying the conversion process from conjunctive normal form to disjunctive normal form in attribute reduction, we find that the conversion efficiency can be properly improved by reducing the redundant formula and the iterative calculations. Taking into account the dynamic change of the normal form, we design an incremental conversion algorithm which converts and simplifies at the same time and can directly calculate by using existing results. For decrement situation, we extract the mathematical model of normal form conversion, give the construction form of corresponding conversion and the analysis process, and also propose an approximate reduction conversion algorithm, therefore realises the dynamic calculation in regard to generating the disjunctive normal form in different variation circumstances. Finally, through simulation experiments we verify the feasibility and efficiency of the algorithm.

关 键 词：约简 增量 析取范式 合取范式 范式转换 

分 类 号：TP18[自动化与计算机技术—控制理论与控制工程]