系统工程理论与实践
繫統工程理論與實踐
계통공정이론여실천
Systems Engineering—Theory & Practice
2013年
9期
2371~2380
,共null页
粗糙集 正区域 冲突域 属性约简 核属性
粗糙集 正區域 遲突域 屬性約簡 覈屬性
조조집 정구역 충돌역 속성약간 핵속성
rough set; positive region; conflict region; attribute reduction; core attribute
针对因决策表中存在不一致对象造成的约简求解错误,同时为了进一步提高约简算法求解效率,首先,给出简化决策表的定义,并证明了简化决策表的核属性和属性约简与原始决策表的核属性和属性约简是等价的.然后,提出冲突域的概念,分析冲突域的性质,以冲突域中冲突对象个数的变化为度量依据,研究核属性和属性重要性的性质,同时设计相应的核属性和属性重要性求解算法;在此基础上,设计基于冲突域渐减式属性约简算法,算法的时间和空间复杂度分别为O(|C|-2|U/C|)和O(|U|).最后的实例和实验结果表明该方法是正确的,高效的.
針對因決策錶中存在不一緻對象造成的約簡求解錯誤,同時為瞭進一步提高約簡算法求解效率,首先,給齣簡化決策錶的定義,併證明瞭簡化決策錶的覈屬性和屬性約簡與原始決策錶的覈屬性和屬性約簡是等價的.然後,提齣遲突域的概唸,分析遲突域的性質,以遲突域中遲突對象箇數的變化為度量依據,研究覈屬性和屬性重要性的性質,同時設計相應的覈屬性和屬性重要性求解算法;在此基礎上,設計基于遲突域漸減式屬性約簡算法,算法的時間和空間複雜度分彆為O(|C|-2|U/C|)和O(|U|).最後的實例和實驗結果錶明該方法是正確的,高效的.
침대인결책표중존재불일치대상조성적약간구해착오,동시위료진일보제고약간산법구해효솔,수선,급출간화결책표적정의,병증명료간화결책표적핵속성화속성약간여원시결책표적핵속성화속성약간시등개적.연후,제출충돌역적개념,분석충돌역적성질,이충돌역중충돌대상개수적변화위도량의거,연구핵속성화속성중요성적성질,동시설계상응적핵속성화속성중요성구해산법;재차기출상,설계기우충돌역점감식속성약간산법,산법적시간화공간복잡도분별위O(|C|-2|U/C|)화O(|U|).최후적실례화실험결과표명해방법시정학적,고효적.
In order to resolve the errors of reduction algorithms for the existence of inconsistent objects in the decision table and enhance the efficiency of reduction algorithm, firstly, the definition of simplied decision table is proposed, and it is proved that the core and attribute reduction acquired from the method are equivalent to the core and attribute reduction of original decision table. Then, the notion and characters of the conflict region are given. The features of the core attribute and attribution importance based on the change of the number of conflict objects are studied, and the corresponding algorithms of computing core attributes and attribute importance are designed respectively. On the basis of above, an attribute reduction algorithm based on conflict region decreasing is designed, which time complexity and space complexity of the algorithm are O(|C|-2|U/C|) and O(|U|). Finally, an example and the experimental results show that the algorithm is correct and efficient.