A companion paper by Andreassen et M. (this issue) introduced and used a nonlinear, compressible, spectral collocation code to address the relative evolutions of two-dimensionM motions obtained in twoand three-dimensionM simulations of gravity wave breaking. That study illustrated the effects of instability on the wave field and mean flow evolution and suggested that two-dimensionM models are u...

Gravitational waves transport very detailed information on the structure and evolution of astrophysical sources. For instance a binary system in the early stages of its evolution emits a wavetrain at specific frequencies that depend on the characteristics of the obital motion; as the orbit shrinks and circularize, due to radiation reaction effects, the orbiting bodies get closer and tidally int...

We present the results of a radio study of the evolution of an active region through its are productivity. The radio study was carried out with data obtained by the Nobeyama Radio Heliograph (NoRH) at 17 GHz. We chose the active region AR 7515 which appeared at the east limb on May 23, 1993 and then evolved during its passage across the disk. We followed its evolution until June 2. This region ...

On a curved surface the front of a point wave evolves in concentric circles which start to overlap and branch after a certain time. This evolution is described by the geodesic ow and helps us to understand the geometry of surfaces. In this paper we compute the evolution of distance circles on polyhedral surfaces and develop a method to visualize the set of circles, their overlapping, branching,...

We present a two-dimensional vertical (2DV) flow and morphological numerical model describing the behaviour of offshore sand waves. The model contains the 2DV shallow water equations, with a free water surface and a general bed load formula. The water movement is coupled to the sediment transport equation by a seabed evolution equation. Using this model, we investigate the evolution of sand wav...

In this paper, we employ the exp(-?(x))-expansion method to find the exact traveling wave solutions involving parameters of nonlinear evolution equations Fitzhugh-Nagumo (FN) equation and Modified Liouville equation. When these parameters are taken to be special values, the solitary wave solutions are derived from the exact traveling wave solutions. It is shown that the proposed method provides...

Availability of short, femtosecond laser pulses has recently made feasible the probing of phases in an atomic or molecular wave-packet (superposition of energy eigenstates). With short duration excitations the initial form of the wave-packet is an essentially real " doorway state " , and this develops phases for each of its component amplitudes as it evolves. It is suggested that these phases a...