MATLAB在常微分方程初值问题的应用

现代科学计算和工程等很多问题中都是用微分方程的形式进行描述,因而研究微分方程具有非常重要的实际意义。本文主要介绍如何使用MATLAB求解常微分方程初值问题。     

森林面积分布系统的最优控制存在性问题

本文研究森林面积分布系统的最优控制问题。本文将林木总和长消率作为控制变量，以“范数最小”来衡量其最优性，利用空间Ｌ＾２（０，Ｔ）Ｔ〉０的自反、光滑和严格凸性，给出了森林面积分布系统最优控制的一个存在性定理。     

关子齐次微分方程的积分曲线

记所论微分方程为(E_λ)_n,本文拓广的不变直线法,在(E_λ)_n的“有理相曲线”与临界、中介水平线”的交、切点与型号间建立起对应关系.依次以各水平线上交、切点型号串得的型列为行,使构成(E_λ)_n的型阵.它表达出λ遍取不同实数值(由-∞至,+∞)时,(E_λ)_n积分曲线的定性变化图景.实际上,它就是的均匀旋转向量场的完全族.     

Methodological foundations of systems methodologies

In social systems science generally, and in management science particularly, recent developments in the variety of types of specific problem-solving methodologies (under the rubric of hard and soft systems approaches) have given an impetus to a line of inquiry, as well as debate on the nature of those methodologies. On the one hand, there has been the view that what we are witnessing is a form of Kuhnian crisis. On the other hand, a complementarist view of developments has been argued and a contingency approach proposed. But one thing has been common among the competing views: a belief that the prospects for further advances in the design and application of those methodologies, and in resolving the current controversies, lie in serious attempts to reconsider and clarify the underlying metatheoretical assumptions and concerns. This paper is an attempt to contribute to such an endeavor. A brief exposition of three methodological foundations (namely, empiricism, hermeneutics, and critique) is made, not only with the purpose of highlighting the nature as well as the limits of their epistemological and ethical claims, but also as a basis for illuminating both the nature of contemporary work on systems inquiry, design, and problem solving and the ongoing debate on what constitutes appropriate criteria for choice of specific methodologies.     

“变截面管中跨声速气流”一文引理的证明

本文对T·P·Liu教授关于“变截面管中跨声速气流”一文的关键性引理给出一个清楚的证明,以使这篇有影响的开创性论文更加完美。     

迟后型时滞控制系统的稳定判断及稳定条件(下)

本文旨在把判断低阶时滞系统稳定性的“截点法”推广到高阶迟后型时滞系统的稳定性判断。文中具体分析了三阶时滞系统的稳定条件,并用计算机模拟证实了有关结论的正确性。此外,本文还提出了判断时滞系统不存在渐近稳定性质的基本理论及无渐近稳定的充分条件。     

Hammerstein系统遗忘因子有限窗口分解辨识

提出一种带遗忘因子和分解辨识策略的有限数据窗口递归最小二乘Hammerstein系统辨识方法。针对Hammerstein系统具有耦合参数的问题,将Hammerstein系统分解为2个子系统：一个子系统包含线性子系统参数,另一个子系统包含非线性子系统参数;提出一种基于遗忘因子的有限窗口递归最小二乘方法对分解模型进行在线递归估计;仿真示例验证了所提算法能够快速跟踪参数,实现对Hammerstein系统的精确辨识。     

A user designer-based systems methodology

This paper develops the argument that in organizational redesign it is desirable to utilize user-designers as the architects for the redesign. A methodology is developed which emphasizes the use of ideal systems models by user-designers to plan for the organization's future. The methodology involves the creation of an ideal system model, then an analysis of the present system through the creation of root definitions and process models of the existing system. Then root definitions and process models for the idealized system are created. Finally, the two are compared and desirable changes are generated which bring the existing system toward the idealized.     

泵引起的液压系统振动分析

通过液压系统产生振动和噪音的振源及振动量传递的分析,开发了测定泵的振源特性的新方法,－２压力／２系统”法,介绍了用阻抗求解管内压力脉动的方法及通用仿真程序包,实验表明,仿真结果与实测结果一致。