To characterize the amount of damping in a system a ratio called the damping ratio ( also known as damping factor and % critical damping ) is used.
22.
Continuous Wavelet Transform ( CWT ) is very efficient in determining the damping ratio of oscillating signals ( e . g . identification of damping in dynamical systems ).
23.
Scaled models can be designed to replicate the dynamic characteristic ( e . g . frequencies, mode shapes and damping ratios ) of their full-scale counterparts.
24.
The damped natural frequency is less than the undamped natural frequency, but for many practical cases the damping ratio is relatively small and hence the difference is negligible.
25.
Where \ zeta is the damping ratio, \ omega _ n is the natural frequency of the cupula, and u ( t ) is the input angular acceleration.
26.
The definition of the damping ratio and natural frequency presumes that the overall feedback system is well approximated by a second order system; i . e . the system has a dominant pair of poles.
27.
Therefore, the damped and undamped description are often dropped when stating the natural frequency ( e . g . with 0.1 damping ratio, the damped natural frequency is only 1 % less than the undamped ).
28.
The method of logarithmic decrement becomes less and less precise as the damping ratio increases past about 0.5; it does not apply at all for a damping ratio greater than 1.0 because the system is overdamped.
29.
The method of logarithmic decrement becomes less and less precise as the damping ratio increases past about 0.5; it does not apply at all for a damping ratio greater than 1.0 because the system is overdamped.
30.
The smooth idealization of design spectrum suggests smaller seismic response with the increased natural periods and effective damping ratio due to SSI . With this assumption, it was traditionally been considered that SSI can conveniently be neglected for conservative design.
