Sea otters (Enhydra lutris) are keystone predators that consume a variety of benthic invertebrates, including the intertidal mussel, Mytilus californianus. By virtue of their competitive dominance, large size, and longevity, M. californianus are ecosystem engineers that form structurally complex beds that provide habitat for diverse invertebrate communities. We investigated whether otters affec...

In this paper we propose an original and statistical method for the sea-oor segmentation and its classi-cation into ve kinds of regions: sand, pebbles, rocks, ridges and dunes. The proposed method is based on the identiication of the cast shadow shapes for each sea-bottom type and consists in four stages of processing. Firstly, the input image is segmented into two kinds of regions: shadow (cor...

A perturbation model for high-frequency sound scattering from an irregular elastic sea bed is considered. The sea bed is assumed homogeneous on the average and two kinds of irregularities are assumed to cause scattering: roughness of the water-sea bed interface and volume inhomogeneities of the sediment mass density and the speeds of compressional and shear waves. The first-order small perturba...

In classical tsunami-generation techniques, one neglects the dynamic sea bed displacement resulting from fracturing of a seismic fault. The present study takes into account these dynamic effects. Earth’s crust is assumed to be a Kelvin-Voigt material. The seismic source is assumed to be a dislocation in a viscoelastic medium. The fluid motion is described by the classical nonlinear shallow wate...

the shape of a submerged vane is a major factor in the design of a vane system and affects the performance and secondary currents generated by the vanes. this study investigated the effect of five vane shapes on bed sediment processes (local scour at the leading edge and transverse distribution of sediment downstream of the vanes) at four flow intensities for a total of 20 experiments. the resu...

In classical tsunami-generation techniques, one neglects the dynamic sea bed displacement resulting from fracturing of a seismic fault. The present study takes into account these dynamic effects. Earth’s crust is assumed to be a Kelvin-Voigt material. The seismic source is assumed to be a dislocation in a viscoelastic medium. The fluid motion is described by the classical nonlinear shallow wate...

The proposed work investigates quantitatively the interaction between wave, currents and seabed sediments in shallow water over a bed characterized by heterogeneous, mud-dominated sediments. The long-term goal of is to develop an approach to characterize accurately the state of a muddy sea bed, based on minimal prior information about bed sediment, and remote observations of surface waves and c...

An algorithm to compute forces at the sea bed from a finite element solution to the mild slope wave equation is devised in this work. The algorithm is best considered as consisting of two logical parts: The first is concerned with the computation of the derivatives to a finite element solution, given the associated mesh; the second is a bi–quadratic least squares fit which serves to model the s...