We synthesize robust nonlinear static output feedback controllers for systems of quasi-linear parabolic partial di!erential equations with time-dependent spatial domains and uncertain variables. The controllers are successfully applied to a typical di!usion}reaction process with moving boundary and uncertainty. ( 2000 Elsevier Science Ltd. All rights reserved.

This paper deals with the orders of input/output equations satis ed by nonlinear systems. Such equations represent di erential (or di erence, in the discrete-time case) relations between highorder derivatives (or shifts, respectively) of input and output signals. It is shown that, under analyticity assumptions, there cannot exist equations of order less than the minimal dimension of any observa...

ABSTRACT: In this article, a two-dimensional cochlear model is proposed in the time domain by using a numerical technique. The equations in this model are discretized with respect to the spatial variables by means of a method of quadrature formulas yielding a system of ordinary di erential equations in the time domain. To solve this system, a variable step size eighth-order Runge-Kutta scheme i...

For xed = (x; t), we consider the solution u(f) to u (x; t) + Au(x; t) = f(x) (x; t); x 2 ; t > 0 u(x; 0) = u(x; 0) = 0; x 2 ; Bju(x; t) = 0; x 2 @ ; t > 0; 1 j m; where u = @u @t , u = @ u @t , R, r 1 is a bounded domain with smooth boundary, A is a uniformly symmetric elliptic di erential operator of order 2m with t-independent smooth coe cients, Bj , 1 j m, are t-independent boundary di eren...

one of the ecient and powerful schemes to solve linear and nonlinear equationsis homotopy analysis method (ham). in this work, we obtain the approximate solution ofa system of partial dierential equations (pdes) by means of ham. for this purpose, wedevelop the concept of ham for a system of pdes as a matrix form. then, we prove theconvergence theorem and apply the proposed method to nd the a...

it is known that a stochastic dierential equation (sde) induces two probabilisticobjects, namely a diusion process and a stochastic ow. while the diusion process isdetermined by the innitesimal mean and variance given by the coecients of the sde,this is not the case for the stochastic ow induced by the sde. in order to characterize thestochastic ow uniquely the innitesimal covariance give...

The aim of this work is to provide a dynamic and multi-layer model that enables the study of human-centred systems. The rst layer of this model is focused on individual behaviour by modelling dynamicrelations that may exist between some psychological factors. This part is extended, in the second layer,to consider inter-worker social relations that in uence the individual performance...

In the last decades fractional di erential equations have become popular among scientists in order to model various stable physical phenom ena with anomalous decay say that are not of exponential type Moreover in discrete time series analysis so called fractional ARMA models have been proposed in the literature in order to model stochastic processes the auto correlation of which also exhibits a...

We announce publicly available Fortran software for the initial value problem IVP in ordinary di erential equations ODEs We describe the interfaces and how Fortran language features a ord the opportunity both to address di erent types and structures of variables and to provide functionality not usually directly associated with IVP solvers

In the past several years, there has been considerable progress made on a general leftde…nite theory associated with a self-adjoint operator A that is bounded below in a Hilbert space H; the term ‘left-de…nite’has its origins in di¤erential equations but Littlejohn and Wellman [25] generalized the main ideas to a general abstract setting. In particular, it is known that such an operator A gener...