frequency range

Optimization of impact dynamic vibration absorbers in the frequency band

The paper deals with the methods of calculation and optimization of constructions of  the impact dynamic vibration absorbers (DVA ) for the elongated structures.  An efficient numerical approach based on the theoretical-experimental method is proposed to maximize the minimal damping of modes in a prescribed frequency range for the tuned-mass impact systems. Methods of decomposition and numerical synthesis are considered on the basis of an adaptive schemes. The influence of dynamic vibration absorbers and basic design elastic and damping properties is under discussion.

Methodical errors of measurement of the human body tissues electrical parameters

Sources of methodical measurement errors of immitance parameters of biological tissues are described. Modeling measurement errors of RC-parameters of biological tissues equivalent circuits into the frequency range is analyzed. Recommendations on the choice of test signal frequency for measurement of these elements is provided