We construct a class of symplectic integration schemes to general Sine–Gordon type systems. We also conduct several numerical tests for these symplectic schemes. Our numerical results demonstrate the effectiveness of these schemes for numerical computation of the solutions to the general...

Inverse problems are considered for the linear one-way one-dimensional wave equation or transport equation. In particular the wave speed reconstruction problem for a medium is discussed. Inverse problems for non-stationary, but also non-dispersive, media are examined; this means problems for which...

We investigate envelope solitary waves on square lattices with two degrees of freedom and nonlinear nearest and next-nearest neighbor interactions. We consider solitary waves which are localized in the direction of their motion and periodically modulated along the perpendicular direction. In the...

We calculated theoretical acceleration response spectra at the ground surface in the region near the 1995 Hyogo-ken Nambu earthquake source based on the spectral moment method. To estimate earthquake motion on the ground surface, a formula of earthquake motion at base rock level was derived. The...

The transport of classical waves in strongly scattering media is investigated using ultrasonic techniques, allowing us to measure both the ballistic and scattered components of the wave field. We find that the ballistic propagation is dramatically slowed down by scattering resonances, although...