Although twin pipelines in series have been used to transport hydrocarbons engineering practice, most previous studies focused on the dynamic response of seabed around a single pipeline. A two-way coupling model fluid–structure–seabed interaction (FSSI) is proposed for study soil and liquefaction caused by waves currents pipelines. The present integrates flow introducing boundary condition velo...

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 seabed can be classified using data from vertical, split-beam echosounders. This was demonstrated recently using amodel parameterized with acoustic estimates of slope, roughness, normal-incidence backscattering strength, and variation of backscattering strength by frequency and incidence angle. These seabed classifications were interpreted and validated using published surficial geology map...

European Member States are required to assess the status of marine waters, including analysis of cumulative effects. We developed a methodology for evaluating the impact of several human activities that constitute 4 direct pressures on the UK (England and Wales) seabed community: smothering, abrasion, obstruction (sealing), and extraction. The method was tested by mapping the spatial extent of ...

medicinal plant species constitute a considerable part of the flora in iran and play a major role in the composition of plant communities. therefore, it is necessary to recognize the factors leading to the establishment and distribution of vegetation. for data sampling (2012), land units were specified. the plot size was determined using minimal area method and number of plots was determined by...

Professor Andrzej Orlowski, a long-time employee of National Marine Fisheries Research Institute, passed away on October 27, 2020. He was an outstanding scientist in the field hydroacoustics. Inventor method use multiple echo measurements to assess type seabed. To this day, is called Orlowski Method. member Physics Section SCOR, NMFRI Scientific Council, Polish Acoustical Society, ICES Fishery ...