The ocean floor is home to a wealth of species, some of which—such as this bamboo coral (Isidella tentaculum)—have only recently been discovered. Proponents of seabed mining claim it causes less ecological damage than terrestrial extraction. But some researchers are concerned that seabed mining could overwhelm deep-sea ecosystems, adding to concerns about the health of the oceans.

This work deals with the derivation of a novel transparent boundary condition (TBC) for the coupling of the standard “parabolic” equation (SPE) in underwater acoustics (assuming cylindrical symmetry) with an elastic parabolic equation (EPE) for modelling the sea bottom extending hereby the existing TBCs for a fluid model of the seabed.

UWB (ultra wide-band) pulse radar is a promising candidate for surveillance systems. The fast SEABED (Shape Estimation Algorithm based on BST and Extraction of Directly scattered waves) imaging algorithm is deployed in the application of UWB pulse radar in fields that require real-time operations. However, since the SEABED algorithm uses signals received at multiple locations, this method eithe...

A technique has been developed to measure the speed of sound in marine sediments at discrete frequencies from 0.6 to 10 kHz by transmitting pulses from acoustic projectors within the water column and measuring the angle to which they are refracted on directional receivers buried in the seabed. The receivers are vectors sensors that measure three-axis acceleration and pressure allowing acoustic ...

The traditional bucket foundation use vertical wall, which like a cup is buried upside down in seabed. A new bucket foundation with partial inclined wall has been proposed in this article. Based on limit equilibrium analysis of threedimensional stress state of foundation, the calculation method of the horizontal bearing capacity of the new bucket foundation has been deduced, which has been veri...

The goal of geoacoustic inversion is to estimate environmental parameters from measured acoustic fields from e.g. a towed array. Though the inversion results have some uncertainty, inversion is an efficient technique to estimate environment parameters. Based on the a posteriori probability density of environmental parameters obtained from inversion, we perform statistical estimation of transmis...

Qeshm Channel is a shallow and narrow waterway located between Qeshm Island and the mainland in the vicinity of Hormuzgan Province, Islamic Republic of Iran. This channel is important because of its economic, industrial, fisheries and navigation role it plays as well as environmental issues it presents in the region. A prognostic study was performed to simulate currents in this channel, using C...

The long-term goals of this work are to improve ocean acoustic reverberation modeling and sonar performance predictions in shallow waters by developing inversion procedures to estimate seabed scattering and geoacoustic properties with uncertainties, as well as investigating the importance of various scattering processes. Important issues include: investigating the angular and frequency dependen...

Today, enterprises collect large amounts of data and leverage the cloud to perform analytics over this data. Since the data is often sensitive, enterprises would prefer to keep it confidential and to hide it even from the cloud operator. Systems such as CryptDB and Monomi can accomplish this by operating mostly on encrypted data; however, these systems rely on expensive cryptographic techniques...