In this paper, a new analytical approach has been presented for solving strongly nonlinear oscillator problems. Iteration perturbation method leads us to high accurate solution. Two different high nonlinear examples are also presented to show the application and accuracy of the presented method. The results are compared with analytical methods and with the numerical solution using Runge-Kutta m...

We consider a wide variety of Helmholtz scattering problems including by Dirichlet, Neumann, and penetrable obstacles. radial perfectly matched layer (PML) show that for any fixed PML width steep-enough scaling angle, the solution is exponentially close, both in frequency tangent to true solution. Moreover, angle large enough width, close width. In fact, exponential bound holds with rate decay ...