一种基于模糊正域类的模糊属性约简方法

为了实现模糊信息系统属性约简问题,探讨一种基于正域类的模糊属性约简方法。利用模糊二元相似关系建立模糊相似类的方法,进而定义决策属性关于条件属性的模糊正域类,得到正域类属性的重要度。结果表明:一方面,实现模糊信息系统属性约简;另一方面,通过取不同的相似精度,得到不同属性约简集。     

元启发式搜索策略在构造模糊分类系统中的应用

论述了使用模拟退火元启发式搜索策略构造模糊分类系统的过程,目的是利用模拟退火原理研制一种精确的模糊分类器,改善与分类问题有关的搜索空间探索与发掘的性能,找到模糊if-then规则的优化集。算法可以从输入数据集中抽取精确的模糊分类规则,并在若干不同预定义类中将其应用于对新数据实例的分类。     

Heavy mineral stratigraphy of sediments from the southern outer shelf of the East China Sea since the last glaciation using fuzzy C-means cluster method

Correspondence analysis and fuzzy C-means cluster methods were used to divide the stratigraphy of heavy mineral assemblages,and the sediment sources and depositional dynamics of the environment reconstructed.The assemblages were taken from marine sediments from the late Pleistocene to the Holocene in Core Q43 situated on the outer shelf of the East China Sea.Based on the variable boundaries of the mineral assemblage at 63 and 228 cmbsf (cm below sea floor),the core might have previously been divided into th...     

Assessing seawater quality with a variable fuzzy recognition model

With the rapid development of the marine economy industry, human exploitation of marine resources is increasing, which is contributing to the growing trend of eutrophication and frequent occurrence of red tide. Accordingly, investigations of seawater quality have attracted a great deal of attention. This study was conducted to construct a seawater environmental quality assessment model based on the variable fuzzy recognition model. The uncertainty and ambiguity of the seawater quality assessment were then considered, combining the monitoring values of evaluation indicators with the standard values of seawater quality. Laizhou Bay was subsequently selected for a case study. In this study, the correct variable model for different parameters was obtained according to the linear and nonlinear features of evaluation objects. Application of the variable fuzzy recognition model for Laizhou Bay, water quality evaluation and comparison with performance obtained using other approaches revealed that the generated model is more reliable than traditional methods, can more reasonably determine the water quality of various samples, and is more suitable for evaluation of a multi-index, multi-level, nonlinear marine environment system; accordingly, the generated model will be an effective tool for seawater quality evaluation.     

Zn上的k次不可约多项式与k阶Carmichael数

设n是合数,如果对一切f（x）∈Zn[x]都满足f（x）nk≡f（x）mod（n,r（x））,那么就称n是模r（x）的k阶Carmichael数,这里r（x）是Zn[x]上的k次首一不可约多项式,用Ck,r（x）表示所有这种数的集合,并且定义Ck=Ur（x）Ck,r（x）.k阶Carmichael数,当k=4时,已证明了n=pq,p,q是不同的奇素数,p2-1,q3-1均整除n4-1,则n∈C4.主要目的是将k=4时得出的结论推广到k≥4的一般情形,利用孙子定理,通过构造Zn上的首一k次不可约多项式f（x）的方法,得出：在k≥4时,设n=pq,如果k=2m,m≥2,pm-1,q2m-1-1均整除nk-1,则n∈Ck;如果k=2m＋1,m≥2,pm-1,pm＋1-1,q2m-1均整除nk-1,则n∈Ck.     

基于模糊分类的UBGM(1,1)-Markov模型在露天矿边坡沉降预测中的应用

针对UBGM(1,1)-Markov模型中存在2个邻近值可能被归属到不同状态,导致预测值产生偏差的问题,结合模糊分类理论,构建基于模糊分类的无偏灰色-马尔科夫模型(unbiased gray-Markov model based on fuzzy classification, FC-UBGM(1,1)-Markov)。首先对UBGM(1,1)模型进行残差修正,然后将修正后拟合值的相对残差序列作为Markov链进行区间划分,再结合模糊分类的隶属度函数,计算相对残差的模糊向量,根据隶属度确定其所属的状态。实际算例表明,该模型比传统UBGM(1,1)-Markov模型的预测效果更好。     

威海市地质环境质量评价

本文在前期资料收集和资源环境承载力评价的基础上,结合威海市当地地质特征,选择地质环境条件、地质环境问题和人类工程活动作为一级评价指标,地形地貌、地下水资源、区域地壳稳定性、地质灾害、地下水污染、海水入侵、人口密度、农业活动、矿业活动作为二级评价指标,采用层次分析法和模糊数学法对威海市地质环境质量进行综合评价.研究结果表...     

济宁市非煤矿山地质环境影响综合评价

济宁市非煤矿产资源丰富,高强度的开采利用给矿区地质环境保护与治理带来巨大挑战.文章分析研究了济宁市非煤矿山地质环境问题的类型、分布、危害程度等基本特征,分别选用层次分析法和模糊综合评价法进行矿山地质环境影响程度评价,探讨两种评价结果的差异,综合划分影响等级,为开展矿山地质环境保护与矿山地质环境问题治理工作提供前提与依据...     

回归直线的拟合度

采用模糊数学的方法研究回归直线与实测点的拟合度,提出回归直线的似合度,给出计算回归直线拟合度的方法。