Oracle 9i Data Guard技术在水调自动化系统中的应用与实施

水调自动化系统是电网运行的重要生产系统,该系统对数据库备份、数据完整性、实时性和并发访问能力等都提出了较高的要求,如何科学地应用商用数据库提供的高级功能构建稳定、可靠、高效的水调自动化系统,成为一个新课题.文中针对该问题,分析比较了多种常见的高可用数据库方案,最终选择应用Oracle Data Guard技术,构建高性能、高可用、低成本、易维护的水调自动化系统.     

Time series analysis of wind speed using VAR and the generalized impulse response technique

This research examines the interdependence in time series wind speed data measured in the same location at four different heights. A multiple-equation system known as a vector autoregression is proposed for characterizing the time series dynamics of wind. Additionally, the recently developed method of generalized impulse response analysis provides insight into the cross-effects of the wind series and their responses to shocks. Findings are based on analysis of contemporaneous wind speed time histories taken at 13, 33, 70 and 160 ft above ground level with a sampling rate of 10 Hz. The results indicate that wind speeds measured at 70 ft was the most variable. Further, the turbulence persisted longer at the 70-ft measurement than at the other heights. The greatest interdependence is observed at 13 ft. Gusts at 160 ft led to the greatest persistence to an “own” shock and led to greatest persistence in the responses of the other wind series.     

航天产品多源可靠性信息的收集与整理--建立可靠性信息数据库

航天产品可靠性信息的来源多样，可靠性信息的时间性、随机性、有价性、时效性和可追溯性等特征，决定了可靠性数据收集应满足真实性、连续性、完整性等基本要求。同时，对多源信息的收集应遵循先进行需求分析，再确定数据收集点并制定数据收集表格的程度进行。给出了信息的适用性准则和信息分类的三维模型。最后结合具体型号航天产品的可靠性工作的要求，给出了可靠性信息数据库系统的整体方案设计。     

关于移动平均过程两系数的推导

对经济预测方法中两公式给出了证明，两公式的系数被显式推导出来，这两个公式是时间序列模型公式，广泛用于经济预测之中，但文献上很难找到推导过程，本文的证明是基本的，无需高深数学知识即可理解．     

Identification environment and robust forecasting for nonlinear time series

In this paper, the methods of time series for nonlinearity are briefly surveyed, with particular attention paid to a new test design based on a neural network specification. The proposed integrated expert system contains two main components: an identification environment and a robust forecasting design. The identification environment can be viewed as a integrated dynamic design in which cognitive capabilities arise as a direct consequence of their self-organizational properties. The integrated framework used for discussing the similarities and differences in the nonlinear time series behavior is presented. Moreover, its performance in prediction proves to be superior than the former work. For the investigation of robust forecasting, we perform a simulation study to demonstrate the applicability and the forecasting performance.     

一种新的时变大系统递阶控制求解方法

研究了一种新的大系统求解方法,利用Taylor级数的性质,将大系统时变递阶控制问题 转化为代数方程的求解问题.该方法简单,易于编成计算机程序.算例表明了它的有效性.     

非线性动态系统“黑箱”建模方法的研究

本文研究弱非线性动态系统“黑箱”建模的理论和方法，并简要给出根据此方法建模的结果。     

THE RECURSIVE FITTING OF SUBSET VARX MODELS

Abstract. A vector time series model of the form A(L)y(t) + B(L)x(t) =ε(t) is known as a vector autoregressive model with exogenous variables (VARX model) and involves a regressand vector y(t) and a regressor vector x(t). This paper provides a method for the recursive fitting of subset VARX models. It suggests the use of ascending recursions in conjunction with an order selection criterion to choose an 'optimum' subset VARX model.     

广义左,右线性递归规则组改写

本文从左，右线性递归规则组的定义出发，提出了广义左，右线性递归规则组的定义，放宽了左，右线性递归规则组寻规则形式的限制，扩展了Ｕｌｌｍａｎ提出的左，右线性递归规则组改写方法的适用范围。本文证明了由广义左，右线性递归规则组向左，右线性规则组转换的相容性，并给出了具体的转换算法。     

针对产品的CAD／CAM一体化技术

本文系统地介绍了一种基于ＣＡＤ工作站，利用Ｉ－ＤＥＡＳ软件实现的针对壳体类零件的ＣＡＤ／ＣＡＭ一体化技术。论述了利用ＰＥＡＲＬ数据库实现的从ＣＡＤ模型到ＣＡＰＰ之间信息的传输，分析了在ＣＡＤ与ＣＡＭ集成中创成式ＣＡＰＰ所起的关键作用，并介绍了利用ＧＮＣ图形辅助数控软件对加工过程的仿真以及机床文件的准备，最后系统能生成正确的数控指令。系统初步实现了ＣＡＤ／ＣＡＭ一体化。