Wq. Zhu et al., EQUIVALENT NONLINEAR-SYSTEM METHOD FOR STOCHASTICALLY EXCITED HAMILTONIAN-SYSTEMS, Journal of applied mechanics, 61(3), 1994, pp. 618-623
An equivalent nonlinear system method is presented to obtain the appro
ximate probability density for the stationary response of multi-degree
-of-freedom nonlinear Hamiltonian systems to Gaussian white noise para
metric and/or external excitations. The equivalent nonlinear systems a
re obtained on the basis of one of the following three criteria: least
mean-squared deficiency of damping forces, dissipation energy balanci
ng, and least mean-squared deficiency of dissipation energies. An exam
ple is given to illustrate the application and validity of the method
and the differences in the three equivalence criteria.