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1.
Target tracking using distributed sensor network is in general a challenging problem because it always needs to deal with real-time processing of noisy information. In this paper the problem of using nonlinear sensors such as distance and direction sensors for estimating a moving target is studied. The problem is formulated as a prudent design of nonlinear filters for a linear system subject to noisy nonlinear measurements and partially unknown input, which is generated by an exogenous system. In the worst case where the input is completely unknown, the exogenous dynamics is reduced to the random walk model. It can be shown that the nonlinear filter will have optimal convergence if the number of the sensors are large enough and the convergence rate will be highly improved if the sensors are deployed appropriately. This actually raises an interesting issue on active sensing: how to optimally move the sensors if they are considered as mobile multi-agent systems? Finally, a simulation example is given to illustrate and validate the construction of our filter.  相似文献   

2.
为了解决标签携带者和阅读器持有者被恶意追踪与监视以及隐私信息泄漏等问题,设计了物联网移动RFID系统隐私保护方案.该方案采用RFID隐私管理服务系统,在标签与阅读器之间根据标签隐私等级实现单向认证或双向认证,在阅读器与信息服务系统之间采用基于模糊身份加密算法实现匿名访问控制.安全性及效能分析表明,此方案不仅增强了标签携带者的隐私保护,还保护了阅读器持有者的身份隐私,且具有一定的效能优势.  相似文献   

3.
空天信息支持反导武器系统拦截作战效果分析   总被引:1,自引:0,他引:1  
应用武器系统杀伤区计算方法,研究空天信息支持反导武器拦截弹道导弹作战效果的评估问题。根据空天信息支持反导武器系统的导弹拦截作战流程和系统间的相互作用关系,设计了衡量空天信息支持反导武器系统导弹拦截作战效果的拦截窗口计算模型。有效地把空天信息引导的及时性和精确性与反导武器系统的作战效果有机结合,能够实现空天信息支持反导武器系统导弹拦截作战效果的综合整体分析和空天信息对反导武器的引导时机和引导精度等关键要素分析。数值仿真实例进一步说明了所取得的主要结果。  相似文献   

4.
统一混沌系统自适应同步控制   总被引:8,自引:2,他引:6  
针对统一混沌系统的自适应同步控制问题,设计了两种控制器:Backstepping控制器和非线性反馈控制器。利用Lyapunov方法证明了应用Backstepping方法和非线性反馈设计控制器能够使统一混沌系统达到渐近同步,为在保密通信领域中的应用奠定了基础。这两种控制器能够实现多种混沌的同步,而且具有很强的抗干扰性能和鲁棒性。其中,非线性反馈控制器对参数未知的统一混沌系统也能进行有效地同步控制。最后进行了数值仿真,仿真结果表明这两种控制器能够有效地同步统一混沌系统。  相似文献   

5.
基于天基信息的反导作战效能分析   总被引:1,自引:0,他引:1  
应用系统效能分析(system effectiveness analysis,SEA)方法,研究天基信息支持反导武器系统的反导作战效能分析问题.根据天基信息支持武器系统的反导作战流程和系统间的相互作用关系,设计了天基信息支持反导作战效能分析的性能度量、使命度量和效能度量算法.算法有效地把武器系统的性能和使命与环境有机结合,能够实现天基信息对武器系统反导作战支持作用效果的综合整体分析和关键指标参数的灵敏度分析.最后的数值仿真实例进一步说明了所取得的主要结果.  相似文献   

6.
不确定非线性系统变结构模糊自适应鲁棒控制   总被引:4,自引:1,他引:3  
考虑一类不确定非线性系统的鲁棒控制器设计问题,在假设系统不确定性函数结构未知的情况下,利用模糊系统对不确定性函数进行逼近,将获得的模糊系统函数作为系统不确定性界函数。在此基础上,提出了一种变结构模糊自适应鲁棒控制算法,该算法在确保系统的滑动模态超平面为渐近可达的前提下,在线对系统模型的控制增益参数和不确定性函数的界参数进行估计。最后以船舶减摇鳍非线性控制系统为例,进行了变结构鲁棒自适应模糊控制器的设计。仿真研究表明,所提出的算法是有效的。  相似文献   

7.
飞行器非线性动力学模型通常包含由未知外界干扰和未建模动态构成的非匹配不确定性。针对建立的飞行器纵向运动仿射非线性模型,提出了一种基于非线性干扰观测器(nonlinear disturbance observer, NDO)的自适应反推非奇异终端滑模(adaptive backstepping nonsingular terminal sliding mode,AB-NTSM)轨迹跟踪控制方法。设计非线性干扰观测器对未知干扰进行观测补偿,无需干扰上界先验知识。设计未建模动态自适应律,提高控制器对系统不确定性的鲁棒性。对3种不同情况的仿真表明,干扰观测器能够实现对不同干扰精确观测,仅在干扰突变时有较大观测误差。在不确定性影响下,采用提出的控制方法,系统能够实现对指定轨迹的稳定跟踪,并有效消除控制信号的抖振。  相似文献   

8.

Cyber-physical systems integrate computing, network and physical environments to make the systems more efficient and cooperative, and have important and extensive application prospects, such as the Internet of things. This paper studies the control problem of nonlinear cyber-physical systems with unknown dynamics and communication delays. A networked learning predictive control scheme is proposed for unknown nonlinear cyber-physical systems. This scheme recursively learns unknown system dynamics, actively compensates for communication delays and accurately tracks a desired reference. Learning multi-step predictors are presented to predict various step ahead outputs of the unknown nonlinear cyber-physical systems. The optimal design of controllers minimises a performance cost function which measures the tracking error predictions and control input increment predictions. The system analysis leads to the stability criteria of closed-loop nonlinear cyber-physical systems employing the networked learning predictive control scheme. An example illustrates the outcomes of the proposed scheme.

  相似文献   

9.
Since any disturbance and fault may lead to significant performance degradation in practical dynamical systems,it is essential for a system to be robust to disturbances but sensitive to faults.For this purpose,this paper proposes a robust fault-detection filter for linear discrete time-varying systems.The algorithm uses H∞ estimator to minimize the worst possible amplification from disturbances to estimate errors,and H_ index to maximize the minimum effect of faults on the residual output of the filter.This approach is applied to the MEMS-based INS/GPS.And simulation results show that the new algorithm can reduce the effect of unknown disturbances and has a high sensitivity to faults.  相似文献   

10.
现有相对约简实际上只是在保持所关心范畴的下近似不变的前提下对属性进行约简,这对于不协调信息系统来说,可能会使所关心范畴的上近似变大,从而使其近似精度减小,导致有用信息的丢失.为此,针对属性约简中的近似问题进行了研究,引入近似相对约简概念,利用近似相对约简替代现有相对约简来处理不协调信息系统,以克服现有相对约简在不协调信息系统中所带来的缺陷.同时,证明了在协调信息系统下,条件属性集相对决策属性集的近似相对约简和相对约简是等价的,并提出了一种基于近似相对约简的简便属性约简算法.  相似文献   

11.
In the classical theory of self-tuning regulators, it always requires that the conditional variances of the systems noises are bounded. However, such a requirement may not be satisfied when modeling many practical systems, and one significant example is the well-known ARCH(autoregressive conditional heteroscedasticity) model in econometrics. The aim of this paper is to consider self-tuning regulators of linear stochastic systems with both unknown parameters and conditional heteroscedastic noises, where the adaptive controller will be designed based on both the weighted least-squares algorithm and the certainty equivalence principle. The authors will show that under some natural conditions on the system structure and the noises with unbounded conditional variances, the closed-loop adaptive control system will be globally stable and the tracking error will be asymptotically optimal.Thus, this paper provides a significant extension of the classical theory on self-tuning regulators with expanded applicability.  相似文献   

12.
Adaptive stabilization for cascade nonlinear systems   总被引:1,自引:0,他引:1  
An adaptive controller of full state feedback for certain cascade nonlinear systems achieving input-to-state stability with respect to unknown bounded disturbance is designed using backstepping and control Lyapunov function (CLF) techniques. We show that unknown bounded disturbance can be estimated by update laws, which requires less information on unknown disturbance, as a part of stabilizing control. The design method achieves the desired property: global robust stability. Our contribution is illustrated with the example of a disturbed pendulum.  相似文献   

13.
利用面向对象的设计思想和方法 ,提出了一种在 DSS中实现信息反馈的方案 ,定义了系统中主要类的组成 ,着重研究了信息反馈对模型选择、策略分析以及策略选择的支持作用 ,分析了含信息反馈的 DSS中的信息流程 ,建立了相应 DSS的结构框架  相似文献   

14.
系统辩证论的提出和阐述,引起了人们的关注、兴趣和重视。它与唯物辩证论在本质上是一致的,既坚持了唯物主义,又是立意更高的唯物辩证论的另一种表达形式;它有马克思主义哲学和系统科学两个理论来源,出自实践并接受实践的检验,是哲学“走出书斋”的重大理论成果,用它来认识事物已越来越成为一种趋势;它不是对唯物辩证论的否定,而是对马克思主义哲学的丰富和发展,是对系统科学的超越,是哲学领域思想解放的生动体现。  相似文献   

15.
There has been an increasing interest in integrating decision support systems (DSS) and expert systems (ES) to provide decision makers a more accessible, productive and domain-independent information and computing environment. This paper is aimed at designing a multiple expert systems integrated decision support system (MESIDSS) to enhance decision makers' ability in more complex cases. The basic framework, management system of multiple ESs, and functions of MESIDSS are presented. The applications of MESIDSS in large-scale decision making processes are discussed from the following aspects of problem decomposing, dynamic combination of multiple ESs, link of multiple bases and decision coordinating. Finally, a summary and some ideas for the future are presented.  相似文献   

16.
In this paper, PID (proportional-integral-derivative) controllers will be designed to solve the tracking problem for a class of coupled multi-agent systems, where each agent is described by a second-order high-dimensional nonlinear uncertain dynamical system, which only has access to its own tracking error information and does not need to communicate with others. This paper will show that a 3-dimensional manifold can be constructed based on the information about the Lipschitz constants of the system nonlinear dynamics, such that whenever the three parameters of each PID controller are chosen from the manifold, the whole multi-agent system can be stabilized globally and the tracking error of each agent approaches to zero asymptotically. For a class of coupled first-order multi-agent nonlinear uncertain systems, a PI controller will be designed to stabilize the whole system.  相似文献   

17.
18.
1 IntroductionBuilding a data warehouse is an effective way for accommodating enormous historical datathat should be subject oriented and organised in hierarchies, and for providing a goodenvironment for knowledge discovery. Dimensional modelling is a logical design techniqueoften used for data warehousing. Every hierarchy related to a concept is reflected in thedefinition of a dimension.Summary information at all leve1s defined using dimensions accounts for most of thecontents in a data wareh…  相似文献   

19.
分析和研究基于web分布仿真应用系统的特点,针对此类系统难于控制海量异构仿真资源、用户体验不连续等瓶颈,结合网格技术和web标准工具,提出了-种网格环境下基于web的仿真训练系统(GWSTS).设计整个系统在网格环境下的运行调用机制,给出了详细的实现方案.为了提供更好的用户交互体验和解决网页全局刷新问题,引入了Ajax异步通信机制.分析了训练过程中数据在网页中的实时显示和浏览器与本地仿真组件之间的交互问题,给出基于ActiveX的解决方案.  相似文献   

20.
VariableStructureControllerDesignofSingularSystemswithDisturbanceintheCaseofIncompleteStateInformation¥WENXiangcaiandLIUYongq...  相似文献   

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