关联规则挖掘的Apriori算法的改进

提出一种将Apriori算法与散列技术和事务压缩技术相结合的改进算法,研究了散列函数的构造及其对算法效率的影响,分析了事务压缩技术的原理及其实现方法,用实例给出了原算法与改进算法的实现步骤,结果表明,新算法减小了存储空间,提高了算法的效率,并改进了数据挖掘技术的性能。     

基于神经网络的PID控制器研究

本文应用人工神经网络的原理,提出一种新的神经网络的智能PID控制器. 仿真结果表明,此NNPID控制器对线性、弱非线性时不变系统比传统的PID有好 的控制效果;对中等非线性系统和含有噪声扰动的线性知非线性系统有单纯PID 不能达到的控制效果.     

Comparison of bootstrap estimation intervals to forecast arithmetic mean and median air passenger demand

The aim of this paper is to compare passenger (pax) demand between airports based on the arithmetic mean (MPD) and the median pax demand (MePD). A three phases approach is applied. First phase, we use bootstrap procedures to estimate the distribution of the arithmetic MPD and the MePD for each block of routes distance; second phase, we use percentile, standard, bias corrected, and bias corrected accelerated methods to calculate bootstrap confidence bands for the MPD and the MePD; and third phase, we implement Monte Carlo (MC) experiments to analyse the finite sample performance of the applied bootstrap. Our results conclude that it is more meaningful to use the estimation of MePD rather than the estimation of MPD in the air transport industry. By carrying out MC experiments, we demonstrate that the bootstrap methods produce coverages close to the nominal for the MPD and the MePD.     

应用于考古数据处理的决策树算法研究

数据挖掘技术是在近来信息化进程的发展和人们对信息需求的快速增加的大背景下应运而生的一项新技术。考古研究的进步使得找寻考古数据之间关系、并以此为途径研究其背后的社会和历史发展规律成为主题,将数据挖掘技术引入考古研究领域正好顺应了这一大趋势。决策树算法是典型的数据挖掘中的分类算法。为了适应考古研究的具体要求,我们基于C4.5算法,提出了两点改进:增加了一个表示研究背景的参数向量以改进决策树算法无法充分利用先验背景的确定;改变了分裂判定准则——信息增益率的计算方法以提高算法运行速度。经过检验二者都获得了较好的效果。     

基于GSM网络的定位系统的实现

叙述了基于GSM网络的定位系统的系统框架及实现方案,分析了定位演示系统的红外通信接口协议及协议所采用的状态转换原理图;讨论了定位演示系统定位算法的原理和方法,建立了定位演示系统所采用的信道模型;同时给出了在微小区环境下的测试结果。结果表明:该方案能通过无线蜂窝系统完成手机相对位置计算,并结合电子地图很好地得到手机的绝对位置,最终完成了定位跟踪。     

利用线性回归算法评价教师教育信息化问题

在理论分析教师教育信息化影响因素的基础上,提出了利用线性回归分析来评价教师教育信息化若干问题的方法,给出了实现算法,建立了评价模型。并以三峡库区为实例,对三峡库区的教师教育信息化情况进行了综合评价。     

A refinement of Hoeffding's inequality

In this paper, we present a refinement of Hoeffding's inequality which is of closed form and which significantly improves on this inequality in many cases. Some numerical comparisons are also presented.     

ESTIMATION OF A PROPORTION USING SEVERAL INDEPENDENT SAMPLES OF BINOMIAL MIXTURES

This paper considers a sequence of independent counts, with each count arising from a mixture of binomial distributions; the mixing distribution is fixed but the number of trials varies from count to count. In this common situation, an estimate of the underlying mean binomial proportion is needed. Two estimators are in general use: the arithmetic average and a weighted average of the observed proportions. Variances of the two estimators are compared and used to decide which estimator is preferred in a given context. The relative merits depend on the distribution of the proportions and the numbers of trials used.     

基于链表的关联规则挖掘算法

提出了基于链表的关联规则挖掘算法的基本思想，只需要扫描数据库一次．不产生候选项目集，也不使用逐层迭代的方法，利用链表的特性来提高挖掘效率．     

数学符号的历史渊源及实质

数学是通过数学符号来传递信息的。认清代数学和几何学中常用符号的历史渊源 ,从而更好地了解和领会数学符号的来源和含义实质。