Abstract. Reverse-time migration (RTM) of teleseismic converted and free-surface reflected phases has been successful in helping to constrain the structure of the crust and upper mantle, but its accuracy is to a large extent determined by the background velocity model used in the underlying wave propagation. To this end, we develop a technique for RTM based wave-equation reflection tomography i...

The Rotation-Modified Korteweg-deVries (RMKdV) equation differs from the ordinary KdV equation only through an extra undifferentiated term due to Coriolis force. This article describes the steadily-travelling, spatially-periodic solutions which have peaks of identical size. These generalize the “cnoidal” waves of the KdV equation. There are five overlapping regimes in the parameter space. We de...

This paper analyzes the chaotic characteristics of irregular systems using both wave theory and ray theory. In ray theory, we visualize the chaotic properties of the ray propagation trajectories in a chaotic wave field. We found that the trajectory of the billiard problem with a stadium boundary condition has the same sensitivities to the initial conditions as does the mapping process on a logi...

Quasi-Monte Carlo quadrature methods have been used for several decades. Their accuracy ranges from excellent to poor, depending on the problem. This article discusses how quasi-Monte Carlo quadrature error can be assessed, and what are the factors that innuence it.

Using single-step approximations to the propagator, we show that real-time correlation functions can be expressed as integrals of smooth functions, and thus can be efficiently evaluated by Monte Carlo methods. This approach allows direct calculation of correlation functions at intermediate temperatures over short to intermediate time lengths. 2008 Elsevier B.V. All rights reserved.

One of the common concrete channels in irrigation networks is the semielliptical prefabricated channels. Manning formula is usually used to design these channels. The cross-sectional area and the wetted perimeter are required to be calculated in Manning formula. There are no analytical solutions to directly compute these parameters. Thus, numerical integration methods are inevitably used. In th...