preprint-author: 
T. Kruger, L. D. Pustyl'nikov, and S. E. Troubetzkoy
preprint-title: 
Acceleration of Bouncing Balls in External Fields
preprint-abstract: 

We introduce two models, the Fermi-Ulam model in an external field and a one dimensional system of bouncing balls in an external field above a periodically oscillating plate. For both models we investigate the possibility of unbounded motion. In a special case the two models are equivalent.

preprint-year: 
1994