Vol.4, No 17, 2005 pp. 279-285
UDC 517.518.82+517.538(045)=20

ITERATIVE PROCESSES AND PADÉ APPROXIMANTS
I. V. Andrianov1, J. Awrejcewicz2, G. Kudra2
1Institut für Allgemeine Mechanik, RWTH Aachen, Templergraben 64,
D-52056, Aachen, Germany
2Technical University of Łódź, Department of Automatics and Biomechanics,
1/15 Stefanowski St., 90-924 Łódź, Poland

Abstract. In many application oriented researches the initial coefficients characterizng a discontinuity of the governing differential equations (for instance, caused by the dry friction) are often substituted by the continuous functions (approximations). One of the effective methods to use the described methodology is that related to introducing a formal small (perturbation) parameter, and then to carry out the successive iterations due to this parameter. In this paper we show, that a combination of the mentioned iterative  procedure with the Padé approximants leads to a drastic decrease of the number of iterations.
Key words: iterative processes, Padé approximations

ITERATIVNI PROCESI I PADÉ-OVA APROKSIMACIJA
U mnogim istraživanjima orjentisanim ka primeni, početni koeficijenti koji karakterišu diferencijalne jednačine (uzrokovani npr. trenjem) često se zamenjuju kontinualnim funkcijama (aproksimacija). Jedan od efektivnih metoda za korišćenje opisane metodologije zasniva se na uvođenju formalno malog (preturbacionog) parametra, a zatim na izvođenju sukcesivnih iteracija po ovom parametru. U ovom radu pokazali smo da kombinacija pomenute iterativne procedure i Padé-ove aproksimacije vodi ka značajnom smanjenju broja iteracija.
Ključne reči: iterativni procesi, Padé-ova aproksimacija.