Vol.2, No 10, 2000 pp. 1137-1148
UDC 519.218.7:531.36:629.7.058.6
ASYMPTOMATIC BEHAVIOR OF NON-LINEAR
DYNAMIC SYSTEMS SUBJECTED TO PARAMETRIC
AND RANDOM EXCITATIONS
Svetlana Janković, Miljana Jovanović
Faculty of science, Department of Mathematics, University of Niš
Ćirila i Metodija 2, 18000 Niš, Yugoslavia
E-mail: svjank@archimed.filfak.ni.ac.yu
mima@archimed.filfak.ni.ac.yu

Abstract. In this paper we investigate the asymptotic behavior, in the (2k)-th moment sense, of the non-linear oscillator amplitude subjected to small parametric perturbations and random excitations of a Gaussian white noise type. Since this problem is essentially connected with the stochastic differential equation of the Itô type, the present paper deals with the asymptotic behavior of the solution of the Itô's differential equation with small perturbations, by comparing it with the solution of the corresponding unperturbed equation. Precisely, we give conditions under which these solutions are close in the (2k)-th moment sense on intervals whose length tends to infinity as small perturbations tend to zero.

ASIMPTOTSKO PONAŠANJE
NELINEARNIH DINAMIČKIH SISTEMA
POD UTICAJEM PARAMETARSKIH I SLUČAJNIH POBUDA
U radu se ispituje asimptotsko ponašanje, u smislu momenata (2k)-tog reda, amplitude nelinearnog oscilatora pod uticajem malih parametarskih perturbacija i slučajnih pobuda tipa Gaussovog šuma. Pošto je ovaj problem esencijalno povezan sa stohastičkom diferencijalnom jednačinom tipa Itôa, ovaj rad razmatra asimptotsko ponašanje rešenja Itôove diferencijalne jednačine sa malim perturbacijama, upoređujući ga sa rešenjima odgovarajuće neperturbovane jednačine. Preciznije, dati su uslovi pri kojima su ova rešenja bliska u smislu momenata (2k)-tog reda na intervalima čija dužina teži beskonačnosti kada male perturbacije teže ka nuli.