有限维空间中的二阶非自治退化多值微分系统

本文利用集值映射的性质证明了一类有限维空间上的二阶非自治退化多值可微系统的解的存在性。     

The Future of Systems Thinking

Due to the diminishing popularity of systems thinking, an attempt is done to predict its future in the university world. Two starting points are used: one in the traditional scientific community, being its habitat; and the other in the surrounding society, being its area of application. The investigation shows that systems thinking is highly needed, although its nearest future seems bleak. The systemic challenge to the traditional academic world has unfortunately been taken as a threat against its existence. The scientific and educational impact of systems thinking is therefore opposed as an alternative to the old scientific paradigm. Furthermore, the resistance to new theories moving across disciplinary boundaries seems stronger than resistance to theories within the disciplines.     

运动性气单胞菌分离和鉴定方法的研究

通过碱性蛋白胨水 (APW)的增菌效果与气单胞菌培养基 (RYAN)的选择性效果试验 ,建立了运动性气单胞菌细菌学分离和鉴定的实验室检测程序。应用该程序对 8个模拟阳性样品和 71个动物产品、养殖水样及动物病料进行检测 ,结果模拟感染菌全部被分离到 ,从 71个检测样品中分离到 2 0株运动性气单胞菌。实验表明 ,所建立的分离和鉴定方法简便、快速、敏感。此外本文对用生化特性判定细菌致病力的可行性作了探讨     

可控硅励磁独立控制系统

本文通过在2450轧机上应用的双闭环、有环流及带有负荷调节器的可控硅励磁独立控制系统的理论分析,表明该系统可以消除零位振荡,限制咬钢时的冲击电流,同时提高了系统的快速性和稳定性,比非独立励磁控制系统和三环系统结构简单、性能优越,并可满足轧制工艺要求。     

Dealing with coercion: Critical Systems Heuristics and beyond

This paper begins with an introduction to the philosophy and methodology of Critical Systems Heuristics (CSH). Following this, various citicisms of CSH are reviewed. One particularly important criticism is that CSH should not be seen as a replacement for other systems approaches, but as complementary to them. It is this idea of complementarity that has led several Critical Systems thinkers to take CSH, along with a number of other systems methods, and try to show that they are most appropriately used in different contexts. CSH, it is said, is at its most useful when we are confronted with coercive situations. However, in this paper it is argued that coercion is usually characterised by closure of debate. Therefore CSH, which depends upon the possibility of communication (or arbitration) between stakeholder groups, becomes redundant when coercion is experienced. It is further argued that coercion can only be addressed adequately by widening our definition of systems practice to include campaigning and direct political action. There is still considerable scope for developing these areas in the systems domain.     

基于内模控制的系统辨识实验信号设计

以内模控制作为研究对象,在系统的未建模动态用加性不确定性表示时,取评价辨识模型的指标为系统输入端误差的平方均值。将辨识模型表示为一组正交基函数的和,与最小二乘法相结合,得到一种辨识实验信号的设计方法。该方法具有控制性能的相关性,可以获得比普通的随机信号更好的辨识结果。仿真结果证明了方法的有效性。     

从人工生命到人工社会--复杂社会系统研究的现状和展望

介绍了人工社会研究工作的内容、方法及其思想基础，并对其应用和未来趋势进行展望。文中简述了社会学研究的历史阶段、主要问题和困难，人工生命和人工社会方法的有效性，并着重描述了Epstein和Axtell的工作，以及相应的涌现方法在复杂社会系统研究中的中心作用。本文还讨论了目前对人工社会方法的各种批判意见及其回应。     

广义系统渐近稳定分析与镇定的Lyapunov方法

利用Lyapunov方法研究了广义系统的渐近稳定性分析及控制问题,首先提出一种新形式的Lyapunov方程,用来研究广义系统渐近稳定性与镇定问题,同时给出了利用Lyapunov方程判定具有脉冲形式下广义系统渐近稳定的充分必要条件。利用相应的Riccati方程完成镇定广义系统的状态反馈控制器的设计。本文所有结论对广义系统有无脉冲行为均适用。最后利用数值例子说明主要结果。     

IKE协议阶段1安全性分析

章主要分析了IKE协议阶段1的各种鉴别方式的消息交换，比较不同鉴别方式密钥的机密性强度及身份鉴别特点．最后讨化了阶段1中存在的缺陷．     

Global Stabilization of Nonlinear Systems with Byrnes—Isidori Normal Form

1　IntroductionThe problem of the asymptotic stabilization of minimum phase nonlinear systems viasmooth state feedback has been well studied in[1— 6 ].One major methodology is by useof the nonlinear analog of the nonlinear zero dynamics notion so that,un…