Consider hard balls in a bounded rotating drum. If there is no gravitation then Fermi acceleration, i.e., the energy of remains forever. gravitation, acceleration may arise. A number explicit formulas for system without are given. Some these based on an realization, which we derive, well-known microcanonical ensemble measure.

This study has investigated the question how the radiated spectra of a tom-tom changes with striking force. Five tom-toms of different size were recorded at four dynamic levels (pp, mp, mf and ff) and their averaged spectra analysed. It was observed that the number of modes excited increase with playing strength, seen in the radiated spectra as a characteristic change in slope for higher freque...

this research compares the psychological well-being of female heads of household and woman in male-headed in city of tehran. it was a descriptive cross-sectional study. statistical population was consisted of female heads of family under coverage of imam khomeini aid committee and woman in male-headed households in city of tehran in 2012. the sample consisted of 280 subjects including 140 femal...