查询词典 frequent

Since any frequent itemset is a subset of a maximal frequent itemset (an itemset is maximal frequent if it has no superset that is frequent), this paper proposes the DMFI (Discovery of Maximal Frequent Itemsets) algorithm for mining all the maximal frequent itemsets from data sets. This algorithm searches the maximal frequent itemsets in data sets from both bottom-up and top-down directions in the meantime. This paper proposes an algorithm that evaluates the boundaries on the support and confidence of uncalculated itemsets by exploiting the information provided by the calculated itemsets.

本文在经典关联规则的基础上，提出了一系列扩展的关联规则开采算法：发现关联规则的难度体现在发现频繁项目集上，事实上最大频繁项目集（其所有的超集都为非频繁项目集的频繁项目集）的集合已经包含了所有的频繁项目集，本文提出一种发现最大频繁项目集的算法DMFI(Discovery Maximal Frequent Itemsets)，该算法采用自底向上和自顶向下相结合的搜索策略对数据空间进行有效的搜索。

In the analysis of the frequent spectrum and the reflection coefficients, based on Godas two-points method which fit to the normal incident wave, a modified two-points method is derived that can be used to calculate the frequent spectrum and reflection coefficient of the oblique waves from which the frequent spectra of incident waves and reflected waves incoming in arbitrary angular, the bulk reflection coefficient and the frequent spectrum of reflection coefficient could be computed, also from which in theory the waves could be measured in two wave gauges which is disposed at any direction.

为了分析单向不规则波入射波的频率谱和反射系数，本文在Goda用于分析正向不规则波的两点法的基础上，提出了可用于斜向不规则波频谱分离及其反射系数计算的改进两点法，该方法可用于计算任意波浪入射角的入、反射波谱、总体反射系数和反射系数的频率谱，并且测量波浪过程的两浪高仪可在较广的方向范围内布置。

In the analysis of the frequent spectrum and the reflection coefficients, based on Goda's two-points method which fit to the normal incident wave, a modified two-points method is derived that can be used to calculate the frequent spectrum and reflection coefficient of the oblique waves from which the frequent spectra of incident waves and reflected waves incoming in arbitrary angular, the bulk reflection coefficient and the frequent spectrum of reflection coefficient could be computed, also from which in theory the waves could be measured in two wave gauges which is disposed at any direction.

为了分析单向不规则波入射波的频率谱和反射系数，本文在Goda用于分析正向不规则波的两点法的基础上，提出了可用于斜向不规则波频谱分离及其反射系数计算的改进两点法，该方法可用于计算任意波浪入射角的入、反射波谱、总体反射系数和反射系数的频率谱，并且测量波浪过程的两浪高仪可在较广的方向范围内布置。

Aiming at the multiple loop structures in quality management process network, an improved graph pattern mining approach based on Apriori algorithm is put forward, where a frequent pattern of size k, denoted as G, is joined with another frequent pattern of size k, denoted as G, to form a candidate frequent pattern of size (k+1), if there exists a source vertex s in G and a sink vertex e in G such that the graph derived from G by subtracting node s equals with the graph derived from G G by subtracting node e.

采用基于APriori方法的频繁活动序列挖掘算法，认为k-频繁图集中，当一个图减去其中的一个源顶点后，如果所得到的图与另一个图减去其中的一个沉顶点后的图相同时，可以连接生成一个(k+1)-候选频繁图，从而减少了传统Apriori算法迭代过程中生成的冗余候选频繁图的数目。

Then, considering the knowledge represented by a set of frequent patterns, we investigate the problems of preserving sensitive patterns in data sharing, hiding sensitive patterns in frequent pattern sharing, and also blocking inference channels in frequent pattern sharing. The main contributions are as follows:(1) For the problem of preserving anonymity in data sharing, we propose a clustering-based approach for implementing l-diversity.

本文首先研究了数据共享中匿名保护问题，接着以频繁模式为知识的表现形式，研究了数据共享中的敏感模式保护，频繁模式共享中的敏感模式隐藏，以及频繁模式共享中的推理控制等问题，主要的研究成果如下：(1)针对数据共享中的匿名保护问题，提出了一种基于聚类的l-多样化实现方法。

Then, considering the knowledge represented by a set of frequent patterns, we investigate the problems of preserving sensitive patterns in data sharing, hiding sensitive patterns in frequent pattern sharing, and also blocking inference channels in frequent pattern sharing.

本文首先研究了数据共享中匿名保护问题，接着以频繁模式为知识的表现形式，研究了数据共享中的敏感模式保护，频繁模式共享中的敏感模式隐藏，以及频繁模式共享中的推理控制等问题，主要的研究成果如下：（1）针对数据共享中的匿名保护问题，提出了一种基于聚类的l-多样化实现方法。

The set of frequent closed patterns determines exactly the complete set of all frequent patterns and is usually much smaller than the laster. Yet mining frequent closed patterns remains to be a memory and time consuming task.

频繁闭合模式集惟一确定频繁模式完全集并且尺寸小得多，然而挖掘频繁闭合模式仍然是时间与存储开销很大的任务。

So, this paper, based on mathematical expectation, brought up the concept of the positively correlated frequent itemsets, and improved the algorithm of mining frequent itemsets directly in FP-tree to mine positively correlated frequent itemsets. In this way, a solution to the above mentioned problems was got.

针对以上问题，基于数学期望，提出了正相关的频繁项集的概念，并改进了一种直接在FP-树中挖掘频繁项集的算法，挖掘出正相关的频繁项集，从而有效地解决以上问题。

In this paper, a new algorithm FPMFI (frequent pattern tree for maximal frequent item sets) for mining maximal frequent item sets is proposed.

另外，算法FPMFI通过删除FP子树(conditional frequent pattern tree)的冗余信息，有效地压缩了 FP 子树的规模，减少了遍历的开销。

An efficient algorithm based on FP-tree and support array for mining maximal frequent itemsets is proposed. At first the FP-tree and the support array are created at the same time. Then a maximal frequent itemsets tree MAXFP-tree is built up to store all the maximal frequent itemsets. Therefore, it can reduce the search space and improve the efficiency of the algorithm.

提出了一个基于频繁模式树即FP-tree和支持度数组相结合的最大频繁项集挖掘算法，首先建立FP-tree，同时建立支持度数组，然后在此基础上建立最大频繁项集树MAXFP-tree，MAXFP-tree中包含了所有最大频繁项集，缩小了搜索空间，提高了算法的效率。

Among which is the mindset, perceptions and moralities of those who accept mini- military tasks for economic gains.

其中最重要的是心态，观念和道德的人谁接受小型军事任务的经济收益。

In time course imaging, activity peaked 2 days after coronary ligation.

在时程成像检测，活性峰值在冠脉结扎后2天。