“…The mass m is connected with a switchable spring of stiffness k α (α = 1, 2) and a switchable damper of coefficient r α (α = 1, 2) in the α-region. The mass of the oscillator is excited by a periodical force, i.e., P α = Q 0 cos(Ωt + φ) + U α for α = 1, 2 (1) where Q 0 and Ω are excitation amplitude and frequency and U α is constant force. The coordinate system is defined by (x, t) both t and x are time and the displacement of mass, respectively.…”