正态云关联规则的预测方法

在信息处理领域,用数据挖掘方法发现关联规则和进行预测是两大热点.文中应用聚类的方法确定正态云的两个参数,并借助正态云模型来划分数量属性的论域,由此生成一系列的正态云关联规则.接着给出了正态云关联规则的挖掘和预测方法.由于用正态云表示的语言值能很好地表达抽象的概念,从而使得挖掘出的正态云关联规则与预测的结果更抽象、更容易被人理解.     

正态云关联规则在预测中的应用

在信息处理领域,用数据挖掘方法发现关联规则和进行预测是两大热点,首先借助正态云模型来替代对数量属性论域的划分,并提出数量属性上的正态云关联规则的概念,接着给出挖掘正态云关联规则的方法,并利用已挖掘出的正态云关联规则进行预测,由于正态云模型较好地软化了数量属性论域的划分边界,从而使得挖掘出的正态云关联规则与预测的结果更容易被人理解。     

挖掘优化的语言值关联规则

文章应用竞争聚集算法(CA算法)代替RFCM算法将数量属性划分成若干个语言值,CA算法综合了分层聚类与划分聚类的优点,它不仅比RFCM算法节省时间,而且能得到优化的固定的聚类个数,因此CA算法能挖掘出优化的语言值关联规则。文中没有把语言值表示成正态模糊数模型,从而可以避免产生不必要的误差.最后应用CA算法挖掘一个气象仿真实例的优化的语言值关联规则。     

基于模糊划分的数据挖掘算法在电厂燃烧优化系统中的应用

电厂锅炉燃烧系统具有多输入、多输出、大滞后和强非线性特性.为了优化燃烧过程,提高机组热效率,关键问题是确定机组运行主要可控参数的优化目标值.本文采用基于模糊划分的多值属性数据挖掘算法来确定重要参数的运行优化目标值.将模糊集合理论引入到关联规则的研究中,利用模糊概念对数据进行概括和抽象,通过定义在属性论域上的模糊集来软化边界.此方法能将多值属性关联规则的挖掘问题转化为布尔型关联规则的挖掘问题.通过实验验证了算法的可行性并对算法的性能进行了讨论,说明了本文中提出的挖掘算法能发现关系数据库中数量型属性之间的蕴涵的关联性.最后以600 Mw机组历史实测参数为基础数据,对各种不同特征负荷工况下的数据进行挖掘.得到各自的最优值,并将这些最优值用于指导实际运行,取得了显著的效果.     

区间值关系数据库上模糊关联规则的预测方法

讨论了区间值关系数据库上模糊关联规则的挖掘算法与预测方法。采用一种比RFCM算法省时的FCMdd算法将记录在属性的取值划分成若干个模糊集,并提出区间值关系数据库上模糊关联规则的挖掘算法。仿真实例说明挖掘算法能够通过挖掘有意义的模糊关联规则来发现区间值关系数据库中蕴涵的关联性。区间值关系数据库上模糊关联规则的预测方法改进了标准可加性模型,并通过遗传算法调整模糊关联规则中三角模糊数的参数来提高预测的精度。     

用模糊方法挖掘量化关联规则

量化关联规则挖掘的一个关键问题是对连续数量值属性的划分,论文采用模糊划分来解决这个问题,实现了数据的平滑过渡,并在此基础上给出了模糊量化关联规则的形式化定义和挖掘算法。     

时间序列模糊关联规则的挖掘

对于许多复杂系统产生的时间序列,研究序列的局部行为和局部关联特征往往比原来的研究系统全局性模型具有明显的优势。为研究时间序列内部或时间序列间局部形态的关联特征,文章借助模糊集来软化时间序列属性论域的划分边界从而研究时间序列局部形态的模糊关联规则、规则可信度和规则的评价方法。实际算例显示了算法的有效性。     

基于云模型的多维关联规则研究

本文利用云模型对数据软划分的理论和方法使相邻属性值可以重叠,利用云变换方法完成数值型属性与布尔型属性的转换,给出了一种云多维关联规则的定义,提出了ApfioK_Cube_Cloud算法对云化后的数据进行多维关联规则挖掘,这种方法较好地软化了数量属性论域的划分边界,从而使发现的规则更让人理解也更符合实际.     

对计算机通信网络安全的现状与预防的探讨

本文利用云模型对数据软划分的理论和方法使相邻属性值可以重叠,利用云变换方法完成数值型属性与布尔型属性的转换,给出了一种云多维关联规则的定义,提出了ApfioK_Cube_Cloud算法对云化后的数据进行多维关联规则挖掘,这种方法较好地软化了数量属性论域的划分边界,从而使发现的规则更让人理解也更符合实际.     

挖掘集合值关系数据库的模糊关联规则

为了挖掘集合值关系数据库的模糊关联规则，应用竞争聚集算法将记录在数量型属性上的取值划分成若干个模糊集，接着给出集合值关系数据库上数量型属的模糊关联规则的挖掘算法，此算法能将数量型属性模糊关联规则的挖掘问题转化为布尔属性关联规则的挖掘问题。最后通过一个实例说明挖掘算法的合理性。     

基于模糊分类关联规则的分类系统

为了构建高性能的分类系统，应用模糊集软化数量型属性的划分边界，提出了模糊分类关联规则的挖掘算法。由于模糊集能很好地贴近人类的思维方式，因此挖掘得到的模糊分类关联规则易于被人理解．接着提出了基于模糊分类关联规则的分类系统，并采用遗传优化算法训练分类系统．实例分析的结果表明，基于模糊分类关联规则的分类系统具有较好的精度和可解释性．     

Mining Fuzzy Multiple-Level Association Rules from Quantitative Data

Machine-learning and data-mining techniques have been developed to turn data into useful task-oriented knowledge. Most algorithms for mining association rules identify relationships among transactions using binary values and find rules at a single-concept level. Transactions with quantitative values and items with hierarchical relationships are, however, commonly seen in real-world applications. This paper proposes a fuzzy multiple-level mining algorithm for extracting knowledge implicit in transactions stored as quantitative values. The proposed algorithm adopts a top-down progressively deepening approach to finding large itemsets. It integrates fuzzy-set concepts, data-mining technologies and multiple-level taxonomy to find fuzzy association rules from transaction data sets. Each item uses only the linguistic term with the maximum cardinality in later mining processes, thus making the number of fuzzy regions to be processed the same as the number of original items. The algorithm therefore focuses on the most important linguistic terms for reduced time complexity.     

基于RPCL的模糊关联规则挖掘

在模糊关联规则的挖掘过程中,很难预先知道每个属性合适的模糊集。针对该问题,提出基于次胜者受罚竞争学习的模糊关联规则挖掘算法,无需先验知识,即可根据每个属性的性质找出对应的模糊集,并确定模糊集的数目。实验结果表明,与同类算法相比,该算法可以挖掘出更多有趣的关联规则。     

基于改进多层次模糊关联规则的定量数据挖掘算法

针对单一层次结构实现规则提取具有规则提取准确性不高、算法运行时间长、难以满足用户使用需求的问题,提出一种基于改进多层次模糊关联规则的定量数据挖掘算法。采用高频项目集合,通过不断深化迭代的方法形成自顶向下的挖掘过程,整合模糊集合理论、数据挖掘算法以及多层次分类技术,从事务数据集中寻找模糊关联规则,挖掘出储存在多层次结构事务数据库中定量值信息的隐含知识,实现用户的定制化信息挖掘需求。实验结果表明,提出的数据挖掘算法在挖掘精度和运算时间方面相较于其他算法具有突出优势,可为多层次关联规则提取方法的实际应用带来新的发展空间。     

一种改进的模糊关联算法及其在IDS中的应用

关联规则的发现是数据挖掘中的一个重要问题,但只是对离散型数据进行处理。为解决连续数量值属性的划分出现的“尖锐边界”问题,采用模糊划分,实现数据平滑过渡。由于入侵检测系统(IDS)对训练数据要求不高,文中提出了一种使用哈希链表改进模糊关联规则挖掘的新算法,且在挖掘过程中使用了等价类快速查找频繁项集,避免了反复扫描数据库及大量重复计算检验步骤。通过一个入侵检测系统的算例显示了其优越性,来提高对入侵数据的识别能力。     

Utilizing Genetic Algorithms to Optimize Membership Functions for Fuzzy Weighted Association Rules Mining

It is not an easy task to know a priori the most appropriate fuzzy sets that cover the domains of quantitative attributes for fuzzy association rules mining. In general, it is unrealistic that experts can always provide such sets. And finding the most appropriate fuzzy sets becomes a more complex problem when items are not considered to have equal importance and the support and confidence parameters required for the association rules mining process are specified as linguistic terms. Existing clustering based automated methods are not satisfactory because they do not consider the optimization of the discovered membership functions. In order to tackle this problem, we propose Genetic Algorithms (GAs) based clustering method, which dynamically adjusts the fuzzy sets to provide maximum profit based on user specified linguistic minimum support and confidence terms. This is achieved by tuning the base values of the membership functions for each quantitative attribute with respect to two different evaluation functions maximizing the number of large itemsets and the average of the confidence intervals of the generated rules. To the best of our knowledge, this is the first effort in this direction. Experiments conducted on 100 K transactions from the adult database of United States census in year 2000 demonstrate that the proposed clustering method exhibits good performance in terms of the number of produced large itemsets and interesting association rules.     

Genetic-Fuzzy Data Mining With Divide-and-Conquer Strategy

Data mining is most commonly used in attempts to induce association rules from transaction data. Most previous studies focused on binary-valued transaction data. Transaction data in real-world applications, however, usually consist of quantitative values. This paper, thus, proposes a fuzzy data-mining algorithm for extracting both association rules and membership functions from quantitative transactions. A genetic algorithm (GA)-based framework for finding membership functions suitable for mining problems is proposed. The fitness of each set of membership functions is evaluated by the fuzzy-supports of the linguistic terms in the large 1-itemsets and by the suitability of the derived membership functions. The evaluation by the fuzzy supports of large 1-itemsets is much faster than that when considering all itemsets or interesting association rules. It can also help divide-and-conquer the derivation process of the membership functions for different items. The proposed GA framework, thus, maintains multiple populations, each for one item's membership functions. The final best sets of membership functions in all the populations are then gathered together to be used for mining fuzzy association rules. Experiments are conducted to analyze different fitness functions and set different fitness functions and setting different supports and confidences. Experiments are also conducted to compare the proposed algorithm, the one with uniform fuzzy partition, and the existing one without divide-and-conquer, with results validating the performance of the proposed algorithm.