有关平均值的不等式及其证明

对两个平均值不等式，给出只用一元函数一阶导数的证明方法，同时对更为一般的平均值不等式，给出了统一的证明。     

A fractionally integrated exponential model for UK unemployment

Fractionally integrated models with the disturbances following a Bloomfield ( 1973 ) exponential spectral model are proposed in this article for modelling UK unemployment. This gives us a better understanding of the low‐frequency dynamics affecting the series without relying on any particular ARMA specification for its short‐run components which, in general, require many more parameters to estimate. The results indicate that this exponential model, confounded with fractional integration, may be a feasible way of modelling unemployment. It also shows that its order of integration is much higher than one and thus leads to the conclusion that the standard practice of taking first differences may lead to erroneous results. Copyright © 2001 John Wiley & Sons, Ltd.     

多元对称函数驻点的讨论

运用严密的逻辑推理，对标准多元对称函数及非标准多元对称函数求驻点的解法做了深入的探讨，并给出了一种简洁且实用的方法。     

平纹变化组织的计算机辅助设计

以平纹变化组织为例,介绍一种基于Matlab的变化组织设计和程序实现方法.根据平纹变化织物组织的设计原理, 通过矩阵变换的方法建立了常见平纹变化组织相应的矩阵模型.通过程序实现平纹变化组织矩阵的自动构造和组织图的自动绘制.实践表明,通过Matlab语言对于织物组织矩阵变换具有简便、直观的优点,对进一步开发织物组织CAD程序具有一定的参考价值.     

基于分数次Logistic方程的技术创新传播模式的稳定性分析

利用分数次微分方程的定性理论,给出了基于分数次Logistic方程网络式技术创新传播模式平衡点的稳定性分析,为创新技术的开发与积累提供了理论依据.     

Forecasting high‐frequency financial data with the ARFIMA–ARCH model

Financial data series are often described as exhibiting two non‐standard time series features. First, variance often changes over time, with alternating phases of high and low volatility. Such behaviour is well captured by ARCH models. Second, long memory may cause a slower decay of the autocorrelation function than would be implied by ARMA models. Fractionally integrated models have been offered as explanations. Recently, the ARFIMA–ARCH model class has been suggested as a way of coping with both phenomena simultaneously. For estimation we implement the bias correction of Cox and Reid ( 1987 ). For daily data on the Swiss 1‐month Euromarket interest rate during the period 1986–1989, the ARFIMA–ARCH (5,d,2/4) model with non‐integer d is selected by AIC. Model‐based out‐of‐sample forecasts for the mean are better than predictions based on conditionally homoscedastic white noise only for longer horizons (τ > 40). Regarding volatility forecasts, however, the selected ARFIMA–ARCH models dominate. Copyright © 2001 John Wiley & Sons, Ltd.     

直线磨擦驱动带式输送机辅机长度和位置确定的研究

在对直线摩擦驱动带式输送机生产原理、现状及典型工况分析的基础上，摸拟出10多个数学模型，并根据模型利用计算机处理计算出该类输送机正常运转时辅机长度及位置的重要参数，为优化设计提供依据。     

广义凸分式多目标规划的有效性条件

文中考虑了非光滑分式多目标规划问题,提出了一类称之为(C,α,β,,ρd)-凸性的广义凸概念,展示了其性质定理.并且在这一广义凸性假设下获得了广义凸非光滑分式多目标规划的全局有效性条件.     

仪表飞行仿真系统的实现

为缩短训练飞行员的周期,提高训练飞行员的质量,设计并实现了一种仪表飞行仿真系统。对系统中使用的各种技术进行了深入的研究,包括应用系数构造法实现空气动力学模型,采用基于组件的方式实现控制系统模型部分,应用树形结构组织管理各种数据以及使用XML(extensib le M arkup Language)语言定义配置文件等。在控制系统部分还给出应用基本控制组件实现PID(Proportional Integral Derivative)反馈控制器。这种基于组件的方式有效地提高了控制系统的灵活性及可扩展性。该仪表飞行仿真系统已应用到国产某型号飞机飞行员训练中,如果不加控制信号,可保持平飞状态30 s左右,非常接近实际飞行状态。实践证明,该系统在实时性和仿真度等方面均符合需求。