The third condition is
underdamping with [[zeta].sub.1] < 1 and [alpha] > 1.
It is for this reason that a reasonable interval for stiffness proportional damping ratio [[xi].sub.[beta]] is needed in the relevant simulations to avoid the aforementioned issues induced by both over- and
underdamping of high-frequency response.
Therefore, when c > [c.sub.c], it represents the overdamping coefficient, and when c < [c.sub.c], it is the
underdamping coefficient.
And the effects of the different damping coefficients including the
underdamping coefficients and overdamping coefficients on the SNR are investigated.
Further, the roots are allocated as
underdamping form to improve the responsiveness of the control system; then we have
where h(t) = (1/[[omega].sub.d])[e.sup.-[omega][xi]t] sin([[omega].sub.d]t) with [[omega].sub.d] = [omega][square root of 1 - [[xi].sup.2]], assuming
underdamping ([xi] < 1).
