The maritime domain continues to be important for our society. Significant investments continue to be made to increase our knowledge about what “happens” underwater, whether at or near the sea surface, within the water column, or at the seabed. The latest geophysical, archaeological, and oceanographical surveys deliver more accurate global knowledge at increased resolutions. Surveillance applic...

Although the techniques of cooperative transmission have been developed for terrestrial sensor networks in recent years to improve the bit error rate (BER) performance, the unique characteristics of the underwater acoustic communication channel, such as large and variable propagation delay and the three-dimensional network topology, make it necessary to reconsider the implementation and analysi...

Applications of underwater sensor networks involve environmental monitoring, disaster prevention, and resource detection. As the importance of these applications has recently grown, underwater sensor networks made up of sensor nodes have to be further investigated. However, little research has been performed to develop an underwater sensor node with communication functionality. In an underwater...

This paper describes the modeling and simulation of an underwater robot glider used in the shallow-water environment. We followed the Equations of motion derived by [2] and simplified dynamic Equations of motion of an underwater glider according to our underwater glider. A simulation code is built and operated in the MATLAB Simulink environment so that we can make improvements to our testing gl...

Maintenance work on the harbor of Setúbal, in Portugal, required the removal of a 14-m deep rocky outcrop at the ship maneuver area, using about 35 kg of Gelamonite, a nitroglycerin-based high-explosive. This important harbor is located in the Sado estuary, a biologically rich environment and an important feeding area for a resident community of bottlenose dolphins. Using different safe range c...

The submarine H.L. Hunley was the first submarine to sink an enemy ship during combat; however, the cause of its sinking has been a mystery for over 150 years. The Hunley set off a 61.2 kg (135 lb) black powder torpedo at a distance less than 5 m (16 ft) off its bow. Scaled experiments were performed that measured black powder and shock tube explosions underwater and propagation of blasts throu...

introduction: management of pediatric blunt abdominal trauma in resource-restricted settings requires precise clinical expertise. in this study, we reviewed pediatric patients who were suspected to have blunt abdominal trauma in a level iii trauma center in iran. materials and methods: in a cross-sectional study, 66 injured children were studied from october 01, 2014 to october 01, 2015 in niks...

Underwater acoustic communication is deemed as the technique that will be widely used for oceanography, data collection, pollution monitoring, offshore exploration and tactical surveillance applications [1]. However, the characteristics of underwater acoustic channels, such as high bit error rate (BER), large round-trip delay, multipath coherence, as well as the half-duplex property of typical ...

In this paper we present an multi-robotic system for underwater exploration, specifically for coastal seas. The novelty of this system is its enhanced performance in underwater localization using underwater acoustic ranging and data transfer between the floats. This process is not dependent on any fixed infrastructure, which is usually a requirement for such missions. An algorithm is implemente...

When adapting computer vision algorithms to underwater imaging, two major differences in image formation occur. While still traveling through the water, light rays are scattered and absorbed depending on their wavelength, creating the typical blue hue and low contrast in underwater images. When entering the underwater housing of the camera, light rays are refracted twice upon passing from water...