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1.
针对工业过程控制系统中的故障具有类型多样、时空独立和非线性等特点,使得检测与诊断效率降低,系统性能下降等问题,提出了一种基于自定义多条件约束的多传感器故障检测与诊断机制;该机制,首先考虑了系统的稳态和时空特征建立了非线性过程控制系统多故障模型,并给出了满足条件判定法则;然后对于系统中的单故障,并发故障和通信故障等类型给出了多条件约束法则及独立特性判断;最后提出了通过自定义多条件约束的多传感器故障检测与诊断机制;实验结果表明,在平均检测概率、稳态特征保持能力和系统功耗等方面明显优于无条件约束的机制,可以显著改善过程控制系统性能.  相似文献   

2.
现代无人机发动机测试项目多、实时性要求高,早期的基于非实时的片上系统不能很好地满足测试要求。本文以某型无人机发动机试车台软件系统实际开发为例,在软件开发中引入了经典RM调度算法,分析了经典RM算法的可调度性判定法则,描述了片上系统任务集设计过程,进行了RM可调度性理论判定。通过对任务集的实际可调度性测试表明:硬件利用率最大可达到93.8%,达到设计指标要求;系统运行稳定可靠,并取得预期效果。  相似文献   

3.
大量现行教材与专著中所表述的“机器数补码首位是符号位”之说,其补码加法法则不能被解释,令人困惑。对机器数补码全字长各位定义了位权,提出了“首位负权记数制”及新的机器数补码数据模型。在这个新的模型下,建立了补码与其真值的等量映射,论证了机器数补码的表值域,论证了补码真值负与非负的判定法则及机器数补码[x]与其真值[y]二者之间相互转换的求解法则;给出了机器数补码的加法法则,论证了在封闭运算条件下机器数补码加法的等效加法运算法则。揭示了机器系统内部补码信息表示的内涵与补码加法法则的真相,建立了“机器数补码全字长数位说”。“机器数补码首位符号说”中种种无可释然的困惑,在“机器数补码全字长数位说”里不复存在。  相似文献   

4.
张一弛  庞建民  赵荣彩 《软件学报》2012,23(12):3149-3160
针对可执行程序恶意性难以判定的情况,提出一种基于证据推理的程序恶意性判定方法.首先,建立程序恶意性判定模型;然后,通过对程序进行反编译,抽取影响程序安全性的特征,建立程序行为集合;使用BP神经网络对模型进行训练得到各个行为的概率分配函数BPAF(basic probability assignment functions),并使用加权和形式的合成法则对程序行为进行合成;最后,实现对程序恶意性的判定.实验结果表明了该方法的有效性.  相似文献   

5.
分析了网络割点的分布式判定算法中的主动探测法和被动探测法,提出了基于右手法则的网络边界探测算法以及基于该算法的网络割点判定算法,并给出了算法的正确性证明。分析表明,上述算法涉及的节点较少,能有效降低通信开销,有利于提高网络的稳定性。  相似文献   

6.
实现工程结构构件模糊聚类归并的冗余聚类筛除法   总被引:3,自引:0,他引:3  
由聚类目标函数导出求解最佳模糊聚类中心的迭代模型,提出判定多维样本聚类归并情况的贴近度指标;为了进一步消除冗余“潮汐力”等不利因素给归并效果带来的偏差,建立了冗余聚类判定及剔除法则.实例表明,该方法可任意控制归并程度,能节约大量钢材,比传统归并方法更有效.  相似文献   

7.
提出基于像素块的边缘直线检测算法.先在取定的像素块中建立模板,在原图上移动像素块并用模板进行比对,对累加变量进行累加,而后用阈值判定法则进行判断,最终确定出边缘直线段.通过编程试验证明了其算法的有效性.  相似文献   

8.
本文从模块的受控存取入手,描述了基于法则系统(Law-Governed SystemLGS)的概念和模型,其中的法则(Law)用来控制大型系统的功能,结构及其演变。作为 LGS 的一个实例,我们给出了刻画面向对象程序设计(OOP)方法特性的一组法则,按 OOP 的不同语义层次,构成了一个基于法则的面向对象系统(Object-OrientedLGS,OOLGS),并给出了 OOLGS 中多重继承的一种实现方法,最后提出了 LGS 实现和应用中的有关问题。  相似文献   

9.
针对含有两个不稳定子系统的线性切换系统,设计一种包含时间驱动和状态驱动两个环节的切换法则,使线性切换系统稳定.在该切换法则下,系统的类Lyapunov函数在两个环节都不需要严格单调递减,使得系统在每个子系统有更长的驻留时间,从而有效降低系统的切换频率.在适当的假设条件下,带时变扰动的线性切换系统在该切换信号下具有良好的鲁棒稳定性.基于此,当系统可观测时,进一步设计了基于观测器的混合切换法则,实现了系统的鲁棒稳定.  相似文献   

10.
TRIZ创新法则已经被广泛应用到多个领域的创造发明问题解决中,其非常适合解决技术矛盾或冲突问题。本文将其创新法则与头脑风暴法相结合,应用到城市引导系统的属性冲突的问题解决中,并通过太原市城市引导系统部分子系统的设计应用,验证了该法则的可行性。同时对其他非工程设计领域的发明创造有一定参考价值。  相似文献   

11.
In this paper, several different concepts of controllability are investigated for a class of linear singular systems which system parameters are piecewise constant. Necessary and sufficient geometric criteria for C‐controllability and R‐controllability of such systems are established, respectively. These conditions can be easily transformed into algebraic form. By applying the principle of duality, C‐observability is discussed as well. Furthermore, the intrinsic relationship between these results and existing results are also discussed. Then, a novel necessary, and sufficient criterion for C‐controllability of linear time‐invariant singular systems is derived as a byproduct.  相似文献   

12.
This paper deals with an average-consensus problem of networked multi-agent systems with heterogeneous time delays. First, a necessary and sufficient condition is derived for multi-agent systems to achieve average consensus. This condition is represented in the form of an algebraic condition by using the delay-transition and the delay-weighted Laplacians. Second, a performance criterion is introduced to evaluate multi-agent systems that do not achieve average consensus. The criterion is represented in terms of the norms with respect to the above Laplacians. These results imply that the introduced Laplacians play important roles in analysing multi-agent systems with heterogeneous time delays. The validity of the analysis results is demonstrated by simulations with six-agent systems.  相似文献   

13.
This paper considers controllability and observability of switched multi-agent systems, which are composed of continuous-time and discrete-time subsystems. First, a controllability criterion is established in terms of the system matrices. Then, by virtue of the concepts of the invariant subspace and the controllable state set, a method is proposed to construct the switching sequence to ensure controllability of switched multi-agent systems, and a necessary and sufficient condition is obtained for controllability. Moreover, a necessary controllability condition is derived in terms of eigenvectors of the Laplican matrix. With respect to observability, two necessary and sufficient algebraic conditions are obtained. Finally, simulation examples are provided to illustrate the theoretical results.  相似文献   

14.
This paper investigates the stationary average consensus problem for second-order discrete-time multi-agent systems (SDMAS). A stationary consensus problem is to find a control algorithm that brings the state of a group of agents to a common constant value which is called the collective decision. We introduce the concept of stationary average consensus of SDMAS and propose a consensus algorithm. Based on the polynomial stability and the graph theory, we obtain two necessary and sufficient conditions of stationary average consensus of SDMAS. The last theorem provides an algebraic criterion of stationary average consensus, and can help us to determine the parameters in the consensus algorithm. Furthermore, in this consensus algorithm, only the states of the agents are transferred among the agents. Therefore, this algorithm can not only solve the stationary average consensus problem but also reduce the amount of transferred data. A numerical example is provided to illustrate the efficiency of our results.  相似文献   

15.
The present paper establishes results for the robust absolute stability of a class of nonlinear continuous-time systems with time-varying matrix uncertainties of polyhedral type and multiple time-varying sector nonlinearities. By using the variational method and the Lyapunov Second Method, criteria for robust absolute stability are obtained in different forms for the given class of systems. Specifically, the parametric classes of Lyapunov functions are determined which define the necessary and sufficient conditions of robust absolute stability. The piecewise linear Lyapunov functions of the infinity vector norm type are applied to derive an algebraic criterion for robust absolute stability in the form of solvability conditions of a set of matrix equations. Several simple sufficient conditions of robust absolute stability are given which become necessary and sufficient for special cases. Two examples are presented as applications of the present results to a particular second-order system and to a specific class of systems with time-varying interval matrices in the linear part.  相似文献   

16.
In this paper, the controllability problem of two-dimensional discrete-time multi-input bilinear systems is completely solved. The homogeneous and the inhomogeneous cases are studied separately and necessary and sufficient conditions for controllability are established by using a linear algebraic method, which are easy to apply. Moreover, for the uncontrollable systems, near-controllability is considered and similar necessary and sufficient conditions are also obtained. Finally, examples are provided to demonstrate the results of this paper.  相似文献   

17.
本文主要研究了驱动–响应结构下的布尔网络的完全同步化, 其中驱动系统是一个周期性时变的布尔网络. 对 于上述问题, 本文基于逻辑系统的代数形式下分两种情况讨论. 对于每种情况, 都将给出一个完全同步的充要条件. 相 应地, 提出了两个响应布尔网络的同步化方案. 最后, 通过一些数值例子来说明本文结果的有效性.  相似文献   

18.
This paper analyzes the eigenvalue distribution of neutral differential systems and the corresponding difference systems, and establishes the relationship between the eigenvalue distribution and delay-independent stability of neutral differential systems. By using the “Complete Discrimination System for Polynomials”, easily testable necessary and sufficient algebraic criteria for delay-independent stability of a class of neutral differential systems are established. The algebraic criteria generalize and unify the relevant results in the literature. Moreover, the maximal delay bound guaranteeing stability can be determined if the systems are not delay-independent stable. Some numerical examples are provided to illustrate the effectiveness of our results.  相似文献   

19.
In this paper, the interrelation between positive invariance, monotonicity and comparison of iterated nonlinear systems defined in partially ordered sets is studied. First, necessary and sufficient conditions guaranteeing the positive invariance of sets defined by relations of the form v(x)≤w with respect to nonlinear systems are established. Then, various characterizations of monotone nonlinear systems are developed and a connection between positive invariance and monotonicity is established. Finally, necessary and sufficient conditions for a, not necessarily monotone, nonlinear system to be a comparison system are established. No specific algebraic structure is necessary for developing the main results of this work. Numerical examples illustrating the applicability of all these results to the case of discrete-time dynamical systems are also given.  相似文献   

20.
不确定广义系统的最优保性能控制   总被引:24,自引:0,他引:24  
该文讨论不确定广义系统的最优保性能控制问题.给出了不确定广义系统保性能控 制器的两种设计方法:一是代数Riccati方程方法,给出了参数化的控制器;另一个是线性矩阵 不等式方法,给出了在使性能函数上界最小的意义下,最优控制器的设计算法,用实例演示了 该方法的有效性.  相似文献   

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