This thesis describes new laboratory observations concerning the interaction between a series of steep incident waves and vertical, surface piercing, cylinders. The motivation for the study arose as a result of wave impact damage sustained to the undersides of several concrete gravity-based structures in the northern North Sea. Earlier work, Swan et al., (1997), demonstrated that in the case of...

Motivated by earlier calculations showing large effects when neutrinos propagate through fluctuating media, we perform here a detailed analysis of how density fluctuations in the sun in the form of helioseismic waves can modify the MSW solution to the solar neutrino problem. We find negligible effects for the MSW spectrum, even under extreme circumstances. There are two main reasons why our con...

We study numerically the dynamics of spiral waves in an excitable medium with negative restitution. For our study we use two models of the excitable medium: a cellular automaton and a reaction-diffusion model. There are no significant effects of negative restitution as long as the slope of the restitution curve is less steep than -1. In media with slopes steeper than -1, the dynamics of spiral ...

Intercellular spread of Ca2+ waves is the primary manifestation of cell-to-cell communication among astrocytes. Ca2+ waves propagate via the release of a diffusible extracellular messenger that has been identified as ATP. In dorsal spinal astrocytes, Ca2+ waves are mediated by activation of two functionally distinct subtypes of metabotropic purinoceptor: the P2Y1 receptor and a receptor previou...

Occurrences of spurious crests on the troughs of large, relatively steep second-order Stokes waves are anomalous and not an inherent characteristic of real waves. Here, the effects of such occurrences on the statistics described by the standard second-order stochastic model are examined theoretically and by way of simulations. Theoretical results and simulations indicate that when spurious occu...

A specific, genuinely three-dimensional mechanism of rogue wave formation, in a late stage of the modulational instability of a perturbed Stokes deep-water wave, is recognized through numerical experiments. The simulations are based on fully nonlinear equations describing weakly three-dimensional potential flows of an ideal fluid with a free surface in terms of conformal variables. Spontaneous ...

Metamaterials constitute a relatively new field which is very promising because it exhibits properties that may not be readily found in nature. One of promising lines of research is the study of novel characteristics of the propagation of electromagnetic (EM) waves in gradient refractive index (GRIN) lenses. In this Thesis, three geometrical optics methods as well as a wave numerical method hav...

In this paper the propagation of harmonic plane waves in a homogeneous anisotropic magneto-piezothermoelastic diffusive body with fractional order derivative is studied. The governing equations for a homogeneous transversely isotropic body in the context of the theory of thermoelasticity with diffusion given by Sherief et al. [1] are considered as a special case. It is found that three types of...

Shockwaves are propagating disturbances with a long history of study in gas dynamics, fluid dynamics, and astrophysics. We also see examples of shocks in everyday life such as a traffic jam, in which the oncoming traffic has much lower density than the cars within the traffic jam. A classical compression wave involves propagation of a discontinuity in which information is absorbed from both sid...

A problem of propagation of very long planetary waves in the upper atmosphere of the Earth is investigated. A new exact solution of the magnetohydrodynamics equations of the ionosphere in the spherical coordinate system is found taking into account the Earth’s rotation and geomagnetic field. The general dispersion equation for the planetary waves in the E and F regions of the ionosphere is deri...