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61.
提出一种采用神经网络非线性系统控制的结构及原理.即采用两个BP神经网络,一个用来对被控系统进行在线辨识,另一个用做非线性自适应控制器.并对具有未知外部负载干扰的电液位置伺服系统进行了动态仿真,讨论了神经元激励函数形状因子、神经网络节点数以及神经网络训练次数对控制系统性能的影响  相似文献   
62.
In a previous paper the author introduced a concept called qualifying function as a conceptual tool for modeling and design. The concept was incorporated into the modeling phase of soft systems methodology (SSM), with the purpose of addressing some of the criticism directed toward the methodology, such as its tendency to result in regulatory, rather than radical, agendas for change. It was argued that the concept had the potential to help people in a particular problem situation to view the situation from new and different perspectives and that it could enrich the conceptual models by giving the transformation process a direction. The aim of this paper is to apply the concept, embedded in SSM, to a case study involving two projects, focused on creating new work opportunities, to explore the practical applicability and usefulness of the concept, both in general and as a part of the modeling phase of SSM.  相似文献   
63.
    
This research project sets out to attempt to answer a simple question: to what extent are systems thinking behaviours and attitudes prevalent in the layperson? It questions the extent to which systems thinking is essentially an academic construct for experiential learning, developed in response to life experiences. This research, undertaken using a triangulation of methods including storytelling, interviews and a quantitative survey, suggests that it may be possible to define the key orientations of the systems thinker, that it could be possible to test for ‘systems thinking orientation’ and that systems thinking education is not essential to the attainment of a ‘systemic outlook’. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
64.
    
For supporting strategy development, corporate practitioners and consultants have long appropriated the roadmap metaphor for journey-making to establish the concept of strategic roadmapping. The practice involves charting future courses of action to help realize a vision. However, despite the significant uptake and use of the method, there still lacks a discourse on its inherent flexibility. Therefore, this paper outlines roadmapping's flexible nature from a systems perspective. The key attributes of the approach being general, scalable, customizable and dynamic are characterized. The governing framework underpinning roadmapping is depicted and described. To provide guidance on deploying this framework, two critical aspects are covered: (i) framing the challenges being faced and contributions necessary to move forward and (ii) with specific regard to having to deal with the realized unfolding of time, the need to flex to evolving conditions and new situational circumstances.  相似文献   
65.
1. INTRODUCTION The robust stability test of time-delay systems with interval parameters is to determine whether the eigenvalues of the characteristic polynomials of the systems are located at open left half complex plane. Different from classical 1-D systems, the eigenvalues of the characteristic polynomials are infinite, classical robust stability results (Kharitonov extreme test and Edge test) for 1-D systems are not suitable for the stability test of the characteristic polynomials of…  相似文献   
66.
通过对参数不匹配、结构不同等情况下Chen氏超混沌系统与Lü氏超混沌系统的异结构同步问题,提出了一种基于自适应控制的超混沌系统同步改进方法;并用双通道实现超混沌同步保密通信:一个通道传送超混沌系统的输出信号实现高精度同步,另一个通道传送用超混沌信号调制的信息信号.该方案利用超混沌信号进行数字信号保密传输,保密性更强;并且仅传输两路超混沌信号即可实现混沌同步和信号调制解调,信道利用率高;同时,自适应控制器设计简单,具有很强的工程应用前景.  相似文献   
67.
许多过程控制系统可以看作混合控制系统。为使设计的控制器满足整个系统一定的过程需求,对象的信息是不可缺少的。本文为这类系统的开发提出了广义对象的形式化模型。基于这样的模型,可以从目标要求中直接提取系统需求,控制器也可以根据基于对象的形式化方法进行设计。我们以一个工业过程控制的实例来说明我们的方法和模型,采用时段演算来描述系统的特性并进行控制器的开发。  相似文献   
68.
在成都建设西部物流中心的系统思考   总被引:2,自引:0,他引:2  
本文在分析了成都发展物流业、构建西部物流中心所具有的优势和不足的基础上,从系统科学的角度,对在成都建设西部物流中心给出对策建议:首先要优化系统的组织结构,要建设健全物流基础设施,培育现代物流企业,对于系统内部要进行调整和改进,尤其在建设物流交通网络时,要考虑不同交通网络的拓扑结构上不同性质;其次西部物流中心是一个动态演化的系统,在建设初期要合理规划,不能一步到位,要留有合理的发展空间;最后从系统和环境的相互作用角度,提出要建立一个有利于系统发展的环境。  相似文献   
69.
    
This paper reconsiders the role of systems thinking in science and addresses an issue raised by Peter Checkland some 25 years ago, that of the relationship between systems thinking, analysis and the scientific method. The paper argues that the scientific method is most usefully interpreted as a dialectic between analysis and synthesis supported by the triadic logic of C.S. Peirce, and that the role of systems thinking is to frame this dialectic. Three generic forms of the system concept are identified—closed systems, input‐output systems and open systems. Consequently, systems thinking is shown to play a central role in mainstream science. The paper concludes that a system is best defined as a cognitive construct for making sense of complexity and the organization of knowledge and that contemporary system thinking is best identified as the ethical, scientific pursuit of knowledge using the socio‐ecological (open) systems frame. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
70.
基于带相关噪声系统的一种最优Kalman滤波算法,应用白噪声估计理论和射影理论,提出了一种带白噪声估值器的固定滞后最优Kalman平滑器。它可递推实现,一个仿真例子说明了其有效性。  相似文献   
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