Some computational issues in optimal control by nonlinear programming

The Roppenecker [11] parameterization of multi-input eigenvalue assignment, which allows for common open- and closed-loop eigenvalues, provides a platform for the investigation of several issues of current interest in robust control. Based on this parameterization, a numerical optimization method for designing a constant gain feedback matrix which assigns the closed-loop eigenvalues to desired locations such that these eigenvalues have low sensitivity to variations in the open-loop state space model was presented in Owens and O'Reilly [8]. In the present paper, two closely related numerical optimization methods are presented. The methods utilize standard (NAG library) unconstrained optimization routines. The first is for designing a minimum gain state feedback matrix which assigns the closed-loop eigenvalues to desired locations, where the measure of gain taken is the Frobenius norm. The second is for designing a state feedback matrix which results in the closed-loop system state matrix having minimum condition number. These algorithms have been shown to give results which are comparable to other available algorithms of far greater conceptual complexity.     

多变量FUZZY关系方程组解的进一步研究

本文给出一个把多变量ＦＵＺＺＹ关系方程组的求解问题转化为单变量ＦＵＺＺＹ关系方程组来加以解决的方法，这一方法被应用到关于解集结构的研究上，获得了良好的结果。     

Modelling energy consumption in manufacturing industry

The major effort in energy modelling has been directed to national and global consumption.This paper describes how the techniques of multivariate statistical analysis can be used to model energy consumption in a production environment with varying levels of production activity and weather conditions.The author discusses how the methods were applied by the Operational Research Department at Lancaster University to a manufacturing group of six companies involved in making various products for the engineering and construction industry. The paper identifies the practical issues that arose through the project and describes how the energy models are used for budgeting monthly fuel consumption and for evaluating new energt policies.     

相关系数矩阵与多元线性相关分析

相关系数指度量两个随机变量间线性关系的无量纲指标,在研究了相关系数矩阵性质及其与多元随机变量线性相关性之间关系的基础上,提出多元线性相关系数的定义,用于衡量多个变鼋间线性相关强弱的无量纲指标.分析表明,所提多元线性相关系数能够较全面地反映变量间的线性相关强度.     

IGCC系统多变量综合优化设计

本文探讨研究IGCC系统无约束时多变量综合优化设计及其系统性能特性规律。本文通过IGCC系统热力特性分析,确定了系统的独立变量,并基于有关部件通用模型组建了 IGCC系统通用模型,为无燃气轮机母型硬件约束时的综合优化设计奠定了基础。结合典型实例的模拟分析,揭示了有别于现行的有约束的设计优化的系统性能特性规律。从而提出 IGCC系统无约束综合优化分析的新方法。     

A certain class of incomplete elliptic integrals and associated definite integrals

In many seemingly diverse physical contexts (including, for example, certain radiation field problems, studies of crystallographic minimal surfaces, the theory of scattering of acoustic or electromagnetic waves by means of an elliptic disk, studies of elliptical crack problems in fracture mechanics, and so on), a remarkably large number of general families of elliptic-type integrals, and indeed also many definite integrals of such families with respect to their modulus (or complementary modulus), are known to arise naturally. Motivated essentially by these and many other potential avenues of their applications, we present here a systematic account of the theory of a certain family of incomplete elliptic integrals in a unified and generalized manner. By means of the familiar Riemann–Liouville fractional differintegral operators, we obtain several explicit hypergeometric representations and apply these representations with a view to deriving various associated definite integrals, not only with respect to the modulus (or complementary modulus), but also with respect to the amplitude of the incomplete elliptic integrals involved therein.     

Model simplification and digital design of multivariable sampled-data control systems via a dominant-data matching method

A dominant-data matching method is developed for model simplification and design of digital multivariable sampled-data control systems. A mixed method combining dominant-data matching and the dominant-pole technique is also derived for determining a stable reduced-degree multivariable digital controller. A real semiactive terminal homing missile system is used as an illustrative example.     

Differentiation of Multivariable Composite Functions and Bell Polynomials

We generalize the Bell polynomials in order to derive an operational tool for the differentiation of composite functions in several variables. In particular we show a formula that relates the Bell polynomials for multivariable composite functions to the classical ones. Some applications are suggested.     

多变量样条有限元法

本文提出了一种基于胡海昌－鹫津久一郎三类变量广义变分原理［１，２］的多变量样条有限元法，文中应用乘积型二元三次Ｂ样条插值函数来构造板壳的广义变量场函数，由三类变量广义变分原理来建立多变理样有限元模型。在计算种种场变量时，既不必求导，又无需用应力应变关系式，可直接算得其结果，因而对各种场变量均有足够的精度，文中，还解算了振动与稳定特征值问题，均得到了精度较好的数值结果。