the current paper focuses on some analytical techniques to solve the non-linear duffing oscillator with large nonlinearity. four different methods have been applied for solution of the equation of motion; the variational iteration method, he’s parameter expanding method, parameterized perturbation method, and the homotopy perturbation method. the results reveal that approximation obtained by th...

this paper investigates the forecasting performance of different time-varying bvar models for iranian inflation. forecast accuracy of a bvar model with litterman’s prior compared with a time-varying bvar model (a version introduced by doan et al., 1984); and a modified time-varying bvar model, where the autoregressive coefficients are held constant and only the deterministic components are allo...

We have already proposed novel robust parameter estimation algorithms of time-varying complex AR (TV-CAR) model for analytic speech signal, which are based on GLS (Generalized Least Square) and its modification of ELS (Extended Least Square). The ELS method is more sophisticated method that can be derived by matrix inversion theorem. We have shown that the methods can achieve robust speech spec...