Systems and reengineering: Relating the reengineering paradigm to systems methodologies

Recently the topic of business process reengineering (BPR) has emerged to prominence in a number of guises, e.g. Hammer and Champy (1993). BPR is accepted here as containing a core paradigm with the potential to mobilize and channel change to secure radical improvements in organizational performance. This is contrasted with Continuous Improvement methods which deliver gradual improvements. In this paper BPR is conceputalised as an approach comprised of an emerging group of systems methodologies. These are related to other approaches and methodologies using the Total Systems Intervention framework of Flood and Jackson (1991). In keeping with the framework the main assumptions and metaphors that underlie the BPR literature are examined. BPR methodologies are characterised as rooted mainly in the hard systems approach with the machine metaphor dominating. The possibility is discussed of BPR methodologies based around other than hard system approaches.     

Towards a theory of game-based non-equilibrium control systems

This paper considers optimization problems for a new kind of control systems based on non-equilibrium dynamic games.To be precise,the authors consider the infinitely repeated games between a human and a machine based on the generic 2×2 game with fixed machine strategy of finite k-step memory.By introducing and analyzing the state transfer graphes(STG),it will be shown that the system state will become periodic after finite steps under the optimal strategy that maximizes the human’s averaged payoff,which helps us to ease the task of finding the optimal strategy considerably. Moreover,the question whether the optimizer will win or lose is investigated and some interesting phenomena are found,e.g.,for the standard Prisoner’s Dilemma game,the human will not lose to the machine while optimizing her own averaged payoff when k = 1;however,when k≥2,she may indeed lose if she focuses on optimizing her own payoff only The robustness of the optimal strategy and identification problem are also considered.It appears that both the framework and the results are beyond those in the classical control theory and the traditional game theory.     

Singular spectrum analysis: methodology and application to economics data

This paper describes the methodology of singular spectrum analysis (SSA) and demonstrate that it is a powerful method of time series analysis and forecasting, particulary for economic time series. The authors consider the application of SSA to the analysis and forecasting of the Iranian national accounts data as provided by the Central Bank of the Islamic Republic of Iran. This research was in part supported by a grant (No. 88/121230) from Institute for Trade Studies and Research (ITSR), Tehran, Iran.     

A new statistical approach for the analysis of uncertain systems

This paper addresses the issues of conservativeness and computational complexity of probabilistic robustness analysis. The authors solve both issues by defining a new sampling strategy and robustness measure. The new measure is shown to be much less conservative than the existing one. The new sampling strategy enables the definition of efficient hierarchical sample reuse algorithms that reduce significantly the computational complexity and make it independent of the dimension of the uncertainty space. Moreover, the authors show that there exists a one to one correspondence between the new and the existing robustness measures and provide a computationally simple algorithm to derive one from the other. This research is supported in part by grants from NASA (NCC5-573), LEQSF (NASA /LEQSF(2001-04)-01), the NNSFC Young Investigator Award for Overseas Collaborative Research (60328304) and a NNSFC grant (10377004).     

INTELLIGENT SECURITY SYSTEMS ENGINEERING FOR MODELING FIRE CRITICAL INCIDENTS： TOWARDS SUSTAINABLE SECURITY

An intelligent security systems engineering approach is used to analyze fire and explosive critical incidents, a growing concern in urban communities. A feed-forward back-propagation neural network models the damages arising from these critical incidents. The overall goal is to promote fire safety and sustainable security. The intelligent security systems engineering prediction model uses a fully connected multilayer neural network and considers a number of factors related to the fire or explosive incident including the type of property affected, the time of day, and the ignition source. The network was trained on a large number of critical incident records reported in Toronto, Canada between 2000 and 2006. Our intelligent security systems engineering approach can help emergency responders by improving critical incident analysis, sustainable security, and fire risk management.     

Assumptional analysis: An elucidation and appraisal for systems practitioners

The purpose of this paper is to review the ‘assumptional analysis’ methodology developed by R. O. Mason and I. I. Mitroff. The importance of this approach is that it was primarily constructed to deal with ill-structured problems at the strategic level in social systems. The 1980s has seen systems practitioners demonstrating an increased interest in exactly this type of problem. The principles and procedures of the approach are set out, its use in three organisations described, and an assessment of its potential contribution to systems practice provided.     

兴安盟人口耕地粮食系统技术经济分析

建立兴安盟人口，耕地，粮食系统的重要指标的数学模型，对系统的运行状态进行技术经济分析，研究人口增长与耕地粮食之间的矛盾，探讨人口，耕地，粮食系统的发展趋势和系统良性循环的途径。提出缓解系统矛盾的设想，为有关决策部门提供参考依据。表2，参5。     

统一混沌系统非线性控制器的设计与分析

提出了一类统一混沌系统的非线性控制器的设计新方法。应用反馈精确线性化方法给出了统一混沌系统的标准型。然后利用线性控制方法对变换后的等价系统中的线性子系统进行了控制器设计,由此设计出原混沌系统的非线性控制器,并证明其具有指数稳定性。仿真结果表明利用反馈线性化方法设计的非线性控制器的有效性。     

Discordant pluralism: A new strategy for critical systems thinking

Systems science is characterised by a huge diversity of theories and practical applications which have arisen since its inception. Each of these theories and ways of practising systems science has legitimate claims for its ability to handle certain kinds of systems problems. Dealing with this diversity can be seen as a critical issue for systems thinking and practice. One approach to handling this rich diversity has been to attempt to capture it in frameworks which align features and positions in a “complementarist” fashion. By reviewing work undertaken by systems thinkers who have advocated such a stance, it will be demonstrated that complementarism has its faults, and can be perceived as an imperialist strategy. A route out of the impasse will be suggested through the use of a form of discordant pluralism, which, if taken up, has the potential for bringing together conflicting perspectives in a new constellation.     

一类非线性切换系统的稳定性分析

主要研究了一类非线性切换系统在某种切换律下的稳定性。证明了如果所有的子系统是线性时变的,并且在系统的Cauchy矩阵的范数满足某种条件的情况下,整个切换系统在任意切换律下是全局指数稳定的。研究了其带非线性扰动项的系统,在适当的假设下,建立了这种系统的全局稳定性特性。研究了某些子系统不满足上述Cauchy矩阵的范数条件的切换系统在某种切换律下的稳定性特性。     

Complex systems and network science: a survey

Complex systems widely exist in nature and human society. There are complex interactions between system elements in a complex system, and systems show complex features at the macro level, such as emergence, self-organization,uncertainty, and dynamics. These complex features make it difficult to understand the internal operation mechanism of complex systems. Networked modeling of complex systems is a favorable means of understanding complex systems. It not only represents complex interactions but...     

一类分布参数混合系统的稳定性分析

将混合系统推广到分布参数环境下,提出分布参数混合系统的概念.基于混合系统和分布参数系统的建模方法,建立了一类分布参数混合系统的模型,并对其稳定性进行分析.运用算子半群理论以及混合系统的五元组描述法及其稳定性关系比较理论的结论,通过选择适当的映射,将分布参数混合系统的的稳定性问题转化为集中参数下混合系统稳定性问题,进而得出了一致渐近稳定的充分条件并加以证明.仿真实例验证了文中结论的正确性.     

一类非线性切换系统观测器设计的新方法

针对一类切换规则为时间依赖型的Lipschitz非线性切换系统,采用驻留时间方法研究了状态观测器设计问题.该切换系统同时含有可观测子系统与不可观测子系统,通过构造合适的Lyapunov函数,并利用矩阵不等式技术得到了保证状态观测器状态估计误差收敛的条件.并给出了观测器设计步骤.进一步,通过矩阵变换将观测器增益求解转化为LMI形式.最后给出了仿真算例说明了该设计方法的有效性.     

T-S模糊系统的一种新型PDC鲁棒模糊控制器设计

针对一类模有界的参数不确定Takagi-Sugeno(T-S)模糊系统,在分析模糊系统前提规则结构的基础上,设计了一种新的并行分配补偿(PDC)控制器,研究了其鲁棒控制问题。基于分段Lyapunov稳定性理论,导出了线性矩阵不等式(LMI)形式的鲁棒控制器设计方法。该方法充分利用了模糊系统隶属度函数的结构信息,降低了采用线性矩阵不等式方法求解的难度。仿真实验证明,通过该方法设计的模糊控制系统,具有良好的鲁棒性能,控制效果良好。     

一类非线性切换系统基于观测器的稳定性分析

针对在实际工程系统中状态不可观测的困难,考虑了同时包含李普希兹非线性干扰项和不确定项的切换系统的稳定性问题.在一定的假设条件下,讨论了系统的滑模观测器.在不确定项满足匹配条件的情况下,基于滑模观测器的设计,利用多李亚普诺夫函数方法得到了保证误差切换系统渐近稳定的充分条件,所设计的滑模观测器成为切换系统的渐近稳定的观测器.这为非线性切换系统利用观测器进行稳定性分析提供了一个新视角.最后通过仿真算例验证了所提方案的正确有效性.     

基于DSPN的多阶段任务系统测试性需求建模与分析

针对多阶段任务系统(PMS)的测试性需求分析问题,提出了一种基于确定与随机Petri网(DSPN)的系统级测试性需求模型(PMS-DSPN)和指标确定方法.PMS-DSPN模型包括系统网(SN)和阶段网(PhN)两部分,每个SN对应于各个子阶段任务的GSPN测试性需求模型;PhN对应于各个阶段任务间的转换过程,并通过关联矩阵进行描述.基于该模型得到PMS任务成功率计算方法,并结合PMS维修代价、测试性设计代价计算方法,构造了系统级测试性指标优化分析模型,进而确定PMS系统级测试性指标.最后通过实例验证该方法的有效性.     

Stability analysis and stabilization for discrete-time singular delay systems

Stability analysis and stabilization for discrete-time singular delay systems are addressed,respectively.Firstly,a sufficient condition for regularity,causality and stability for discrete-time singular delay systems is derived.Then,by applying the skill of matrix theory,the state feedback controller is designed to guarantee the closed-loop discrete-time singular delay systems to be regular,casual and stable.Finally,numerical examples are given to demonstrate the effectiveness of the proposed method.     

严格耗散广义系统的鲁棒性分析与控制

考虑不确定广义系统的鲁棒耗散性分析与控制,其中各不确定参数矩阵具有线性分式形式。针对确定广义系统建立耗散性与正实性之间的等价关系,将不确定广义系统的鲁棒耗散性分析与控制转化为确定广义系统的耗散性分析与控制,利用线性矩阵不等式,给出了不确定广义系统鲁棒严格耗散的充要条件及状态反馈鲁棒严格耗散控制器的设计方法。通过一个数值算例说明所给设计方法的有效性。     

可修系统任务分析与成功性评估模型

通过分析可修系统任务执行时间的特点、任务成功要求以及执行现场维修保障条件,在综合考虑影响任务成功性因素的基础上,给出了四种情况下的任务成功概率评估模型,前三种模型分别是任务执行现场不具备任何维修保障条件下、具备备件快速更换条件下、既具备备件快速更换又具备故障件修复的条件下,对于确定和随机任务执行时间,可修系统在规定最大任务时间内不发生故障的概率。最后一个模型是在任务执行现场既具备备件更换又具备故障件修复的条件下,对于确定和随机任务执行时间,可修系统在有无规定最大任务时间内可以发生故障但总停机时间小于规定最大停机时间的概率。最后,针对其中一个模型,给出了可修算例。     

相邻k-out-of-n:F多状态可修系统的可靠性分析

针对相邻k-out-of-n:F多状态可修系统可靠性指标计算难的问题,提出了两种求解该系统可靠性指标的方法。当系统部件寿命和修理时间都服从指数分布时,方法一首先利用马尔可夫过程理论获得部件的可用度,再用部件的可用度获得系统的瞬态、稳态可用度;方法二针对状态空间巨大的情况,先以一定的标准对状态空间进行截尾,再应用马尔可夫模型获得系统的稳态可用度、首次故障前平均时间、稳态故障频度等可靠性指标。最后通过数值算例说明了所提出方法的有效性。