Two kinds of harmonic problems in control systems

This paper discusses the harmonic problems in control systems from two aspects: One is the harmonic control among different subsystems, and the other is the harmonic control among multiple inputs. Some intrinsic problems in such systems are discussed. It is pointed out that some subsystems must be unstable to stabilize the whole interconnected system by an example. Especially for discrete-time multi-input systems, a necessary and sufficient condition is presented for the strict decrease of the quadratic optimal performance index with the control input extensions. This shows an essential difference between single-input and multi-input control systems. Finally, some future research directions are discussed in harmonic control of interconnected systems, allocation of multi-control inputs, fault-tolerant control, and fault-diagnosis.     

基于仿真的复杂系统可靠性、可用性和MTBF评估文献综述

通过查阅大量文献 ,对应用蒙特卡罗仿真方法评估复杂系统可靠性、可用性和 MTBF进行了全面的分析研究 .通常在评估复杂大型系统的可靠性、可用性和 MTBF方面有 4个主要困难 :系统结构可以很复杂 ;子系统可能服从各种失效分布 ;对于可修系统来说 ,子系统可以服从任意失效和修复分布 ;子系统的失效数据有时也不充分 ,可靠性试验样本趋向于小样本 .用经典统计学去获得它们的统计置信限很困难并且经常是不可能的 .而仿真技术是解决这类问题的一个值得重视的研究方向 .     

基于模糊逻辑系统的复杂相似系统分散全息控制设计

针对复杂系统提出信息库的概念，以此为基础描述了复杂相似系统的概念。针对一类具有相似结构的、由二维子系统组成的复杂系统，采用经典Lyapunov方法和模糊逻辑系统，充分利用相似结构信息和匹配系数，分别给出了设计被控复杂系统镇定和跟踪分散全息控制器的方法。实例仿真结果表明本文所提出的方法是有效的。     

大系统平衡块对角优分解

为了实现大系统的并行处理，大系统的分解总是希望分配给各处理器的任务量是均衡的即分解后的子系统要有平衡的结构（或维数尽量接近），因此，在系统平衡块三角分解的基础上，利用非平衡补偿方法使系统状态方程的系数左阵具有块对角优型，使系统模型简化的结果更为理想。系统平衡对角优分解方法通过实例仿真证明是可行的，并为大系统分散控制的分析与设计提供了新的系统模型简化的手段。     

人机融合社会中的系统调控

科学技术的深入发展和广泛应用正在深刻改变人类社会的生产和生活模式,尤其是信息技术的快速发展,推动人工智能(AI)与人的关系由"辅助"到"互助"和"融合"不断深化.相应地,社会调控对象向着能力不断增强的AI系统以及AI赋能的人和组织演变,社会系统将呈现"信息-物理-社会"的高度耦合,调控环境也相应转换为人机融合的复杂社会系统.这一显著变化将倒逼法律体系的变革,对社会系统调控能力提出更高要求,迫切需要人文社科与科学技术相关方法的交叉融合.论文基于对人机融合社会系统发展的研判,在分析法律体系、控制论、人工智能等所面临挑战的基础上,从法律规制和系统控制的角度,提出将调控工程系统的控制科学与调控社会系统的法律充分结合,在系统科学框架内研究处理人工智能时代社会中的系统调控问题;并进一步归纳探讨了以人为本、优势互补、系统分析、量化支撑、算法规制、博弈控制等若干调控原则和可尝试的前瞻领域,以及需要深入研究的问题.这一思路可望量化表达公平正义等法学基本问题,优化调控系统技术指标,促进人机融合社会系统实现其安全稳定、公平正义、民主自由、和谐发展等价值目标.     

要加强对复杂适应性系统的研究——对自组织理论的反思

简单回顾了自组织理论的发展历史、内容和采用的方法,重点分析了自组织理论的研究对象和研究范围;指出自组织理论在研究复杂系统上的局限性——只适于研究简单巨系统,它研究的是系统演化的结果而非过程;自组织理论使用微分方程作为数学工具,要求子系统之间的相互作用要满足叠加原理而不考虑涌现的情况。在此基础上,本文提出要加强复杂适应性系统的研究,具体有两方面的工作：首先要加强计算机作为数学工具的应用,扩展对系统状态描述的范围;另外要加强对层次性的研究,重点是对涌现问题的分析。最后提出现在加强复杂系统的研究应从实际的具体系统入手。     

基于可靠性指标的系统分级递阶全局优化设计

复杂的工程系统，根据其逻辑构成可以化为多级递阶形式，每级含有若干个子系统，每个子系统既受其上级子系统所控制，同时又控制着其下一级一组子系统，以造价为协调参数，可靠度为解耦参数，给出了系统全局优化设计的分解协调过程     

关于社会环境和社会污染之系统剖析

社会环境和社会污染是具有理论和现实意义的重要概念。运用复杂系统理论进行探讨 ,社会环境是一类特大的复杂系统 ,包括自然、人口、文化、经济政治和社会风尚等五个子系统。社会风尚是社会环境的一种集体效应 ,社会污染与坏的社会风尚密切相关。社会环境与社会风尚决定社会行为 ,是多因素统计地决定的。     

从系统论看我国加入WTO后的社会发展趋势

社会是一个复杂大系统 ,其内部子系统之间在结构、功能和运作方式上必须相互匹配 ,相互协调一致 ,否则就会引起各种不正常社会现象 ,影响社会功能的发挥。中国加入WTO后 ,由于经济体制的彻底转型 ,这种“连锁作用”最终将导致中国社会结构的整体转型     

具有非匹配不确定性相似组合系统的分散鲁棒控制

针对一类具有非匹配不确定性的相似组合系统 ,基于块控原理提出了一种变结构控制设计方法。不确定项存在于各子系统的互联项中 ,可以是非线性的或时变的 ,不满足匹配条件 ,但有界 ;利用反演设计方法来处理系统中的非匹配不确定性 ,再用变结构控制方法来改善系统的性能 ;然后 ,利用Lyapunov稳定性定理证明了闭环系统的信号为最终一致有界且系统的状态收敛于滑模超平面的邻域。最后 ,用一个仿真实例证明了所提出的方法的正确性和有效性。     

Systems thinking for information systems development

Although many information systems development methods (ISDMs) are available, past experience indicates that none of them completely supports the design process. One of the major problems is that the traditional ISDMs represents a poor match for some subsystems or dimensions involved in the information systems design (ISD). This paper presents an integration and interpretation of recent research on the mismatch of the ISDMs with the ISD process and suggests that systems ideas can be used to learn about and clarify our perceptions of the ISD processes. First, some important systems concepts such as systems, subsystem, dimensionality, system types, and characteristics are introduced. Second, some lessons of mismatch learned in the past that are related to those systems concepts are discussed. The discussion includes experiences learned through the ISD process such as communication problems, inadequate analysis of systems maintenance, lack of understanding of the relationship between the nature of the subsystem/dimension to be represented and the selection of tools, difficulties in integrating subsystems and dimensions, as well as Brooks' Law along with others. Third, some recommendations are given concerning how to avoid mismatch with a systems concept phase. Fourth, some guidelines are provided for implementing the tasks of the systems concept phase. Finally, a number of areas where research appears needed are mentioned.     

有不确定未知界的相似组合系统的变结构控制

针对一类具有不确定性的相似组合系统,提出了一种变结构控制设计方法.不确定项存在于子系统的内部及各子系统的互联项中,可以是非线性或时变的,且满足匹配条件,有界但界未知;利用自适应技术估计了系统的不确定性;利用Lyapunov稳定性定理证明了系统的状态收敛于滑模超平面.最后用一个仿真实例证明了提出方法的正确性和有效性.     

Cybernetics and network management (viable system modeling)

This paper presents a recursive modeling method which could be used to conceptualize, design, and develop complex network management structures. It would also enhance the scope for developing and enforcing standards. Today most network management systems concentrate on the alarm handling issues, failing to recognize that all data collected about a network are high valued, providing inputs to many levels of an organization. This becomes especially true where organizations are totally dependent on their Information Technology structures. There are no acceptable easy and cheap solutions to network management, and many of the major issues, such as how to handle the dynamics of networks, require extensive R&D. Network management is all about controlling the behavior of network and computer system resources, and therefore we need to adopt control theories and cybernetics. We need a robust network management building method to avoid chaos and to build the complex network structures required to serve the multinational and global organizations that future markets will require. The recursive modeling approach, proposed here, is just a start toward placing network management within a wider context.     

面向复杂系统运动仿真的信息物理融合建模

传统运动仿真的虚拟建模缺少针对复杂系统中信息子系统与物理子系统的动态性融合建模。融合传统运动学虚拟建模与信息计算的优势,针对运动仿真的精度和实时性难以满足实际工业制造需求的问题,提出面向复杂系统运动仿真的信息物理融合建模方法,并以机械臂的运动学控制为仿真案例进行验证,解决了实际环境中机械臂的驱动与仿真环境虚拟机械臂运动不一致的问题。搭建了复杂系统运动仿真虚实映射平台,集成了虚拟建模环境CoppeliaSim,融合实际机器人的运动反馈,和虚实映射计算模型,确定工业机器人运动方程的唯一位姿解。实验结果表明本文提出的方法实现了工业机器人的虚实映射实时运动仿真。     

Use of Archetypal Structures in Urban Dynamics

The paper demonstrates the use of systems archetypes as a practical method to understand the impact of urban policies and programs on urban dynamics. Systems archetypes are generic templates to represent the structural and behavioral insights in dynamic systems. They highlight counterintuitive behavior of social systems and the recursive nature of complex systems. This paper maps systems archetypes pertaining to the failures in urban programs, as described by Prof. J.W. Forrester in his classic book Urban Dynamics. ‘Fixes that backfire’ is a systems archetype that construes a situation where a fix effective in a short term creates long term behavioral side effects which might need even more fixes. This archetype is mapped onto the failures in urban programs. The insights to the reasons of failures of urban programs through the systems archetypes lens will enable us bring a change in the society and assist policy makers by being cautious of the unintended consequences while devising urban policies. Therefore, an approach has been proposed to deal with urban change by applying archetypal structures to urban problems. The approach illustrated in this paper will enable urban governors and planners, distinguish programs and policies that may or may not lead to desired dynamics.     

我国煤层气产业发展的系统思考

煤层气是一种洁净能源,煤层气产业是我国在十二五期间重点鼓励发展的产业之一,但煤层气产业的发展是一项复杂的系统工程,由内外部诸多子系统组成。本文运用系统工程的理论与方法对煤层气产业的系统结构进行了分析,并在此基础上,提出了优化煤层气产业系统结构的对策,对煤层气产业的系统发展具有一定的指导意义。     

网络--探索复杂性的新途径

简单系统由于非线性关系可以呈现复杂行为，而复杂系统可以遵循简单规则自组形成、近年来，作为探索复杂系统结构和功能的复杂网络引起了国际科学界的高度重视，已成为数理科学、生命科学、社会科学、技术科学和管理科学的研究热点之一．论文首先介绍了在复杂网络研究方面已经取得的某些进展，从典型模型．重要概念，网络分类一直到网络结构涌现，其中也包括了作者所做的工作；然后对某些值得注意的问题做了简短的评述．     

基于系统论的STAMP模型在煤矿事故分析中的应用

为应对大量使用数字组件和构建复杂系统所带来的安全挑战,将系统工程的思想融入事故预防被认为是有效的应对方法.Systems-theoretic accident model and processes(STAMP)正是一种基于系统论的事故分析模型,目前已在航空航天、化工、医疗、交通安全等领域取得良好的应用.本文首次尝试使用STAMP模型详细分析一起煤矿事故,分别从物理过程、基层操作、直接监管、矿级监管和系统设计、省级监管及事故的动态过程等方面对导致事故发生的控制缺陷进行剖析,发现除技术原因和工人违章操作外,自下而上有12个组织机构存在控制错误,导致这些错误的关键原因是该系统分层控制结构中各层之间的反馈回路在系统外部环境改变后发生了变化.总之,煤矿事故是我国第一大生产事故,本文希望能提供一个更系统、广泛的视角,以帮助发现日益复杂的煤矿系统存在的安全隐患,减少类似事故发生的可能性.     

STRUCTURAL DECOMPOSITION AND ITS PROPERTIES OF LINEAR MULTIVARIABLE SINGULAR SYSTEMS

We present in this paper a structural decomposition for linear multivariable singular systems. Such a decomposition has a distinct feature of capturing and displaying all the structural properties, such as the finite and infinite zero structures, invertibility structures, and redundant dynamics of the given system. As its counterpart for non-singular systems, we believe that the technique is a powerful tool in solving control problems for singular systems.     

Statistical Identification of Important Nodes in Biological Systems

Biological systems can be modeled and described by biological networks. Biological networks are typical complex networks with widely real-world applications. Many problems arising in biological systems can be boiled down to the identification of important nodes. For example, biomedical researchers frequently need to identify important genes that potentially leaded to disease phenotypes in animal and explore crucial genes that were responsible for stress responsiveness in plants. To facilitate the identification of important nodes in biological systems, one needs to know network structures or behavioral data of nodes(such as gene expression data). If network topology was known, various centrality measures can be developed to solve the problem; while if only behavioral data of nodes were given, some sophisticated statistical methods can be employed. This paper reviewed some of the recent works on statistical identification of important nodes in biological systems from three aspects, that is,1) in general complex networks based on complex networks theory and epidemic dynamic models; 2)in biological networks based on network motifs; and 3) in plants based on RNA-seq data. The identification of important nodes in a complex system can be seen as a mapping from the system to the ranking score vector of nodes, such mapping is not necessarily with explicit form. The three aspects reflected three typical approaches on ranking nodes in biological systems and can be integrated into one general framework. This paper also proposed some challenges and future works on the related topics. The associated investigations have potential real-world applications in the control of biological systems, network medicine and new variety cultivation of crops.