On the stability of a class of nonlinear hybrid systems

In this paper, we propose new conditions for guaranteeing the stability of nonlinear sampled data systems. In order to do this, we extend Lyapunov theory to this class of systems.     

On the stability of a class of nonlinear hybrid systems

In this paper, we propose new conditions for guaranteeing the stability of nonlinear sampled data systems. In order to do this, we extend Lyapunov theory to this class of systems.     

On energy conservation and P-stability

When applied to the classical dynamical equations, generally, conventional time-stepping methods cannot conserve the total energy exactly, but up to their algebraic order. To obtain an energy-conserving method, we add an energy calibrated parameter to some conventional ones. The periodic stability and phase-lag property of this type of energy-conserving methods are investigated in this note. Some numerical results are reported to illustrate our conclusions.     

On asymptotic optimization of a class of nonlinear stochastic hybrid systems

We consider the problem of control for continuous time stochastic hybrid systems in finite time horizon. The systems considered are nonlinear: the state evolution is a nonlinear function of both the control and the state. The control parameters change at discrete times according to an underlying controlled Markov chain which has finite state and action spaces. The objective is to design a controller which would minimize an expected nonlinear cost of the state trajectory. We show using an averaging procedure, that the above minimization problem can be approximated by the solution of some deterministic optimal control problem. This paper generalizes our previous results obtained for systems whose state evolution is linear in the control.This work is supported by the Australian Research Council. All correspondence should be directed to the first author.     

On Constacyclic Codes over Z_(p_1p_2…p_t)

Let t ≥ 2 be an integer, and let _(p_1, ···, p_t)be distinct primes. By using algebraic properties, the present paper gives a sufficient and necessary condition for the existence of non-trivial self-orthogonal cyclic codes over the ring Z_(p_1p_2···p_t)and the corresponding explicit enumerating formula. And it proves that there does not exist any self-dual cyclic code over Z_(p_1p_2···p_t).     

On a class of integro-differential equations modeling complex systems with nonlinear interactions

This work deals with the qualitative analysis of the initial value problem for a class of large systems of interacting entities in the framework of the mathematical kinetic theory for active particles. The contents are specifically focused on the case where the system interacts with the outer environment and the entities are subject to nonlinearly additive interactions.     

On the existence of homoclinic solutions of a class of discrete nonlinear periodic systems

In this paper, we obtain a new sufficient condition on the existence of homoclinic solutions of a class of discrete nonlinear periodic systems by using critical point theory in combination with periodic approximations. We prove that it is also necessary in some special cases.     

On a class of nonlinear stochastic dynamical systems: Analysis of the transient behaviour

A class of nonlinear dynamical systems with random parameters and initial conditions is considered. The transient time evolution of the mean value of the dependent variable is analyzed both by means of the stochastic averaging method and by Adomian's decomposition method. A proof of the equivalence of the decomposition method to the time series approximation of the dynamical response is provided. An application is made to the Van der Pol equation and finally a comparison between the two previously discussed methods is given.     

The equivalence of L2-stability,the resolvent condition,and strict H-stability

The Kreiss matrix theorem asserts that a family of N × N matrices is L₂-stable if and only if either a resolvent condition (R) or a Hermitian norm condition (H) is satisfied. We give a direct, considerably shorter proof of the power-boundedness of an N × N matrix satisfying (R), sharpening former results by showing that power- boundedness depends, at most, linearly on the dimension N. We also show that L₂-stability is characterized by an H-condition employing a general H-numerical radius instead of the usual H-norm, thus generalizing a sufficient stability criterion, due to Lax and Wendroff.     

Stabilization of a class of nonlinear stochastic systems

The aim of this paper is to study the stabilizability for a class of multi-inputs nonlinear stochastic systems. We prove under general assumptions the existence of a linear feedback law which stabilizes in probability the system at its equilibrium.     

On χ2-test of goodness-of-fit for a class of discrete multivariate models

A model for an n-dimensional random vector which is the sum of v i.i.d. random variables with an exponential family distribution is considered. It is shown that the exact test can be approximated by a χ²-test as v → ∞. As an example a goodness-of-fit test for Poisson-distribution based on observed frequencies is derived.     

Solution and asymptotic/blow-up behaviour of a class of nonlinear dissipative systems

In this paper, we consider a three-parameter class of Liénard type nonlinear dissipative systems of the form . Since such dissipative systems admit an eight-parameter Lie group of point transformations, it follows that there exists a (complex) point transformation mapping such a system into the free particle system . Normally, such an explicit point transformation cannot be found. Here we find such an explicit point transformation through exploiting the group properties of the determining equations that lead to it. Consequently, we obtain the explicit general solution of such dissipative systems. Moreover, we completely characterize the asymptotic and/or finite time blow-up behaviour of such systems in terms of their three parameters and initial data.     

On a class of nonlinear integral equations

In this paper we consider abstract equations of the typeK _ν ν +ν =w ₀, in a closed convex subset of a separable Hilbert spaceH. For eachv in the closed convex subset,K _v :H →H is a bounded linear map. As an application of our abstract result we obtain an existence result for nonlinear integral equations of the typeν(s)+ν(s)∫ ₀ ¹ k(s,t)ν(t)dt =W ₀(s) in the spaceL ² [0,1].     

On a class of nonlinear Neumann problems

Summary Existence theorems for nonlinear Neumann problems with inhomogeneous boundary conditions are established. It is then investigated under which conditions the solutions are uniformly bounded. Uniqueness results for positive solutions are given and the asymptotic behavior of the solutions of the corresponding parabolic equation is discussed. The main tools are fixed point theorems and the method of upper and lower solutions.     

一类广义系统的渐近稳定性

Abstract. This paper is mainly used to determine the asymptotic stability of a class of nonlineargeneralized systems through its slow subsystems under the assumption of regularity. One exam-ple is given.