微积分一种重要类型极限的计算方法

给出了一种类型函数极限运算的公式及其在微积分极限计算中的具体应用,应用此极限公式可以求某些极限运算中参数的值,给出一元函数在某一点连续的充分条件和求一个曲线的渐近线,同时提供了一个命题的证明方法.     

游戏与幼儿自信心的培养

通过对幼儿游戏和自信心培养关系的分析，提出创设良好环境，促进幼儿自主探索、独立思考和发挥自身潜力，有利于培养幼儿的自信心。     

关于极限的几个定理

给出了极限的几个定理及其推论，可以解决或简化某类极限问题。推论2修正了数学通报11（1963）《关于极限的一个定理》。     

Which survey indicators are useful for monitoring consumption? Evidence from European countries

This paper assesses the information content of two survey indicators for consumption developments in the near future for eight European countries in the period 1985–1998. Empirical work on this topic typically focuses on consumer confidence, the perceptions of buyers of consumption goods. This paper examines whether perceptions of sellers of consumption goods, measured by retail trade surveys, may also improve short‐term monitoring of consumption. We find that both consumer confidence and retailer confidence embody valuable information, when analysed in isolation. For France, Italy and Spain we conclude that adding retail confidence does not improve the indicator model once consumer confidence has been included. For the UK the reverse case is obtained. For the remaining four countries we show that combining consumer sentiment and retail trade confidence into a composite indicator leads to optimal results. Our results suggest that incorporating information from retail trade surveys may offer significant benefits for the analysis of short‐term prospects of consumption. Copyright © 2004 John Wiley & Sons, Ltd.     

波动性比率与涨跌幅限制实证研究

从交易机制的角度解释了股市开盘收益率的波动大于收盘收益率的波动的原因。在考虑了涨跌幅限制的存在对股票价格行为的影响后，建立了一个简单的计量模型，提出涨跌停频率的大小与波动率的正相关关系及涨跌停日的日内收益率与次日隔夜收益率的正相关关系的假设，并就中国股市的情况进行了实证分析，得出了与假设一致的结论。这里的研究为“方差比率之谜”提供了新的解释思路。     

非破损检测结构混凝土推定强度的可靠性分析

现行常用的非破损检测结构混凝土抗压强度技术规程中只给出了结构混凝土推定强度的计算方法,其计算结果的可信程度并不能确定.运用概率论知识,引入置信区间的概念,利用非中心t分布建立数学模型,对规程中推定强度进行概率分析,计算其置信度,以供工程实践参考.     

M-泛函的经验似然置信区间

利用经验似然思想，分别讨论不含附加信息和含附加信息时，M-泛函的经验似然置信区间，并推广Zhang Biao (1997) 在独立同分布下的结果。     

基于v-支持向量机的边际电价预测及置信区间估计

引入v-支持向量机，通过构造和求解一个凸优化问题，同时实现了对边际电价的预测和对置信区间的估计，且无需假定预测偏差的概率分布．在v-支持向量回归中，当ε〉0时，v是错误样本的个数占总样本个数份额的上界．利用该性质，边际电价预测的置信度和置信区间可以很自然地用参数1-v和变量ε来表示，这为发电公司进行竞价方案的风险分析打下了很好的基础．算例仿真表明，该方法具有较好的泛化性能和较高的预测精度．     

Study on the Predicting System of Breaking Chip When PCD Tool Cutting Aluminum Alloy

In the field of automobile manufacture, during the aluminum alloy cutting, chip forming and breaking process are very complicated. It is affected by many facto rs. Automatic machining process can not be carried through if the chip enlaces t he workpiece or the tool. So the chip control and breaking are key technology. P CD tool has many traits, such as high cutting efficiency, machining precision an d wearability. It is desired that it be used for machining coloured metals.The p aper present the study of p...     

基于相关系数的正、负关联规则挖掘算法

负关联规则描述的是项目之间的互斥关系，它与传统的正关联规则有着同样重要的作用。然而，大多规则挖掘算法只能挖掘正规则而忽略了负规则的挖掘。本文利用统计学中相关系数的理论，提出一个能同时挖掘正、负关联规则的算法，实验表明该算法是有效的。