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81.
This paper studies impulsive control systems. Several stability criteria are established by employing the method of Lyapunov functions. These criteria may be used for impulsive feedback control design. As an application, impulsive control of the Lorenz chaotic system is discussed. Numerical experiments are carried out for the control of the Lorenz system. It is shown that small and frequent impulses need to be used in order to stabilize the Lorenz system.  相似文献   
82.
83.
In this paper, some solvability problems for functional equations of the form
are studied. Here I is a finite closed interval in , F is an unknown continuous function, and are given continuous maps of I into itself, and , and are real-valued continuous functions on I. Such equations are of interest not only by themselves as an object of analysis, but they are also a necessary link in solving various problems in such diverse fields as integral and functional equations, measure theory, and boundary problems for hyperbolic differential equations. The major part of the proofs is based on the new results in the theory of dynamical systems generated by a noncommutative semigroup with two generators.  相似文献   
84.
§ 1. Introduction  LetΩ R3beasmoothboundedopenset,f(t,x ,v)bethedistributionfunctionofcar riersattimet >0 ,positionvectorx∈Ωandvelocityvectorv∈R3.Theforcefieldactingonthecarriersisdenotedbythe3 dimensionalvectorfunctionE(t,x) ,thepotentialcorespondingtoE(t,x)isdenotedbyu(t,x) ,then (f,E)satisfythefollowingBoltzmann Poissonsystem tf +v· xf +E· vf =Q(f) ,  (t,x ,v)∈R+ ×Ω×R3,(1 .1 )E =- xu ,-Δxu =ρ ,  (t,x) ∈R+ ×Ω ,(1 .2 )whereρ(t,x) =∫R3 f(t,x ,v)dvisthecarriernum…  相似文献   
85.
We investigate a multicomponent anisotropic liquid system. The first spatial moment of the direct correlation function is taken into account to obtain asymptotic expressions for the pairwise correlation functions. In this approximation, we obtain the pairwise correlation functions that describe the system behavior not only in the critical-state neighborhood but also in the noncritical domain. We show that the critical parameters for the anisotropic system differ from those for the isotropic system.  相似文献   
86.
This paper deals with the cost benefit analysis of series systems with warm standby components. The time-to-repair and the time-to-failure for each of the primary and warm standby components is assumed to have the negative exponential distribution. We develop the explicit expressions for the mean time-to-failure, MTTF, and the steady-state availability, A T () for three configurations and perform a comparative analysis. Under the cost/benefit (C/B) criterion, comparisons are made based on assumed numerical values given to the distribution parameters, and to the cost of the components. The configurations are ranked based on: MTTF, A T (), and C/B where B is either MTTF or A T ().  相似文献   
87.
In this paper we first establish a new general criterion for the permanence of Kolmogorov-type systems of nonautonomous functional differential equations. Then, as applications of this criterion we study the permanence of a class of n-species general nonautonomous food chain systems with delay and new sufficient condition are established.  相似文献   
88.
On the general problem of stability for impulsive differential equations   总被引:1,自引:0,他引:1  
Criteria for stability, asymptotical stability and instability of the nontrivial solutions of the impulsive system
  相似文献   
89.
90.
He  Qi-Ming  Li  Hui 《Queueing Systems》2003,44(2):137-160
In this paper, we study the stability conditions of the MMAP[K]/G[K]/1/LCFS preemptive repeat queue. We introduce an embedded Markov chain of matrix M/G/1 type with a tree structure and identify conditions for the Markov chain to be ergodic. First, we present three conventional methods for the stability problem of the queueing system of interest. These methods are either computationally demanding or do not provide accurate information for system stability. Then we introduce a novel approach that develops two linear programs whose solutions provide sufficient conditions for stability or instability of the queueing system. The new approach is numerically efficient. The advantages and disadvantages of the methods introduced in this paper are analyzed both theoretically and numerically.  相似文献   
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