Robust reliable stabilization of uncertain switched neutral systems with delayed switching

This paper investigates the problem of robust reliable control for a class of uncertain switched neutral systems under asynchronous switching, where the switching instants of the controller experience delays with respect to those of the system and the parameter uncertainties are assumed to be norm-bounded. A state feedback controller is proposed to guarantee exponential stability and reliability for switched neutral systems, and the dwell time approach is utilized for the stability analysis and controller design. A numerical example is given to illustrate the effectiveness of the proposed method.     

EXPERIMENTAL STUDY OF THE ASYNCHRONOUS MULTISPLITTING RELAXATION METHODS FOR THE LINEAR COMPLEMENTARITY PROBLEMS

We study the numerical behaviours of the relaxed asynchronous multisplitting methods for the linear complementarity problems by solving some typical problems from practical applications on a real multiprocessor system. Numerical results show that the parallel multisplitting relaxation methods always perform much better than the corresponding sequential alternatives, and that the asynchronous multisplitting relaxation methods often outperform their corresponding synchronous counterparts. Moreover, the two-sweep relaxed multisplitting methods have better convergence properties than their corresponding one-sweep relaxed ones in the sense that they have larger convergence domains and faster convergence speeds. Hence, the asynchronous multisplitting unsymmetric relaxation iterations should be the methods of choice for solving the large sparse linear complementarity problems in the parallel computing environments.     

Robust reliable control for uncertain switched nonlinear systems with time delay under asynchronous switching

This paper investigates the problem of robust reliable control for a class of switched nonlinear systems with time delay and actuator failures under asynchronous switching. When the switching instants of the controller experience delays with respect to those of the system, a kind of reliable controller design method is proposed, and the dwell time approach is utilized for the stability analysis. Sufficient conditions for the existence of the reliable controller are formulated in terms of a set of LMIs. Then the proposed approach is extended to take into account switched delay systems with Lipschitz nonlinearities and structured uncertainties. Finally, a numerical example is given to illustrate the effectiveness of the proposed method.     

A theoretical study on the water-mediated asynchronous addition between urea and formaldehyde

The reaction between urea and formaldehyde in water solution was theoretically investigated by using B3LYP and MP2 methods.It was found that the addition of the nitrogen atom in urea to the carbonyl group in formaldehyde precedes the proton transfer and the proton migration from water to the carbonyl group occurs before the proton abstraction from the nitrogen.With one or two water molecules involved in the TS.the activation energy barrier is lowered compared to the TS of the mechanism with no water participation.The energy change along the reaction coordinate clearly shows that a zwitterionic-like intermediate does not exist on the PES.The reaction between urea and formaldehyde occurs in a concerted mechanism but with asynchronous characters.This is different from the stepwise mechanism recently found for the amination reactions of formaldehyde.     

Single Parameter Dissipativity and Attractors in DiscreteTirne Asynchronous Systems ∗

Discrete time nonautonomous dynamical systems generated by nonautonomous difference equations are formulated as discrete time skew—product systems consisting of cocycle state mappings that are driven by discrete time autonomous dynamical systems. Forwards and pullback attractors are two possible generalizations of autonomous attractors to such systems. Their existence follows from appropriate forwards or pullback dissipativity conditions. For discrete time nonautonomous dynamical systems generated by asynchronous systems with frequency updating components such a dissipativity condition is usually known for a single starting parameter value of the driving system. Additional conditions that then ensure the existence of a forwards or pullback attractor for such an asynchronous system are investigated here     

并行二级多分裂迭代方法

1．二级多分裂迭代法本义考虑求解线性代数方程组的几种同步与异步二级多分裂迭代法,其中A为nXn非奇异矩阵．多分别选代法考虑A的多种分裂用IF负对角权矩阵EI（ZEI一川进行组合,可得l＝1．多分裂迭代法任给刘始向量。0对k—1,2,…,直到收敛如果（1．2）中对所有l,MI＝Dilg（Al;…;A。。）,EI＝（O,…,O,I,O,…,O）,则多分裂迭代法退化成块Jacobi迭代法,同样,多分裂迭代法具有自然的并行性,若EI的某个对角元为0,则从的对应分量无需计算．当然,（1．3）可用直接法精确求解,如Gauss消去法,LU分解法等,但有…     

异步并行非线性对称Gauss-Seidel迭代算法

1．引言考虑非线性方程组其中A＝（a。。）EL（＊”）为＊一矩阵,B＝（衬。）EL（＊”）为非负矩阵,呐X）一（p。（X。》,4（二）＝（吵k（kk》：＊一＊一为连续的对角映射,而6＝（6k）E＊一为已知向量．这里,什小：”一”均可微,但二者的导函数并不一定连续．这类方程组具有丰富的实际背景．例如,描述冰体溶解过程的著名的Stefan问题,就可归结为问题（1·1）的数值求解（见［l］）．为在多处理机系统上有效地求解问题（1．1）,文山利用这类非线性方程组的特殊结构,建立了一类并行非线性Gauss—Seidel型迭代算法．为避免该算…     

300MVA 脉冲发电机组滑差调节起动装置的设计及研制

300MVA 脉冲发电机是中国 HL-2M 装置的主要供电电源,为了能够满足放电要求,对脉冲发电机 组的起动装置滑差调节器进行了研究。基于绕线异步电动机的电气特性,采用电动机转子外接液体电阻的的方式 起动机组。计算了在采用不同电流起动时液体电阻的大小以及起动时间,计算了电阻碱液流量及容量以及冷却水 流量。根据恒电流起动方式提出了控制策略。确定了滑差调节器的液阻大小、碱液箱容积、碱液流量以及冷却水 流量。对三相液体电阻值进行了测量及调整,以确保机组起动时电动机电流波动很小。调试结果表明,设计的滑 差调节装置是可行的,可以为大功率高压电动机滑差调节装置的设计提供参考。     

水声正交频分复用异步多用户接入方法

水声信道传播时延大导致水声通信网中上行用户同步困难,因此需要接收端具备异步多用户检测能力。针对水声正交频分复用(OFDM)异步多用户系统提出一种基于滑动迭代的异步多用户接入方法,包括重叠截断、干扰消除、频域过采样、多用户信道估计与解码、以及干扰重构5个处理模块,并通过滑动迭代结构同时消除前向干扰和后向干扰影响。仿真结果表明,所提方法在不同异步到达时延,以及有、无信道估计误差下的误比特率均明显低于逐块解调异步接收算法。水池实验结果表明,滑动迭代异步接收算法在多径扩展18 ms、异步到达时延大于或等于循环前缀1.5倍时实现了两用户异步接入的可靠通信。