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Data analysis of an oscillating flapping wing is conducted for developing a transfer function model especially for heave force data series from the CFD environment for different geometries of flapping wings. The wing experiences a combination of vertical and angular oscillatory motion, while travelling at constant forward speed. The vertical motion is induced by the random motion of the ship in waves,...
The continuous development of design tools and analysis procedures has allowed propeller performances to increase progressively during years following more and more stringent design requirements. High propeller efficiency and avoidance of erosive cavitation are considered nowadays basic requests for a well designed propeller. However this may not be enough to meet the requirements of high added value...
The airwake over the helicopter platform of a Canadian Coast Guard (CCG) polar icebreaker was studied experimentally. By application of high speed particle image velocimetry (PIV) on a 1:522 scaled model of the polar icebreaker, quantitative flow filed data were obtained in several vertical and horizontal planes. Present investigation was conducted with two types of the inflow conditions: (i) a uniform...
The aim of the SONIC project is to develop tools to investigate and mitigate the effects of underwater noise generated by shipping. One way to study the contribution of shipping noise to the background noise in the seas is to produce shipping noise maps. The SONIC project delivers the required technical knowledge for noise mapping, based on a source definition of shipping traffic composed of various...
Vessel-source air pollution may have a major impact on the marine environment and ecosystem. In this study, a method based on vessel activity intensity was adopted to estimate the emission of air pollutants generated by the consumption of fuel oils from merchant vessels in the Port of Kaohsiung in 2013. The vessel activities were determined by using the vessel automatic identification system (AIS)...
In this paper, we discuss the impact of the capture effect and multi-user detection on the reception of automatic identification system messages at the satellite. Resorting to simple yet beneficial tools such as the multi-packet reception matrix and the random access approximation of the medium access layer, an insightful model is presented. A comparison with the destructive collision model is also...
A significant amount of Expendable Bathythermograph (XBT) data has been collected in the Mediterranean Sea since 1999 in the framework of operational oceanography activities. The management and storage of such a volume of data poses significant challenges and opportunities. The SeaDataNet project, a pan-European infrastructure for marine data diffusion, provides a convenient way to avoid dispersion...
These last decades spawned a great interest towards low-power High-Frequency (HF) Surface-Wave (SW) radars for ocean remote sensing. By virtue of their over-the-horizon coverage capability and continuous-time mode of operation, these sensors are also effective long-range early-warning tools in maritime situational awareness applications. In this paper we show how it is possible to take advantage of...
The possible reduction of underwater radiated noise (URN) from a chemical tanker by running according to a combinatory curve instead of fixed RPM is assessed by model-scale tests in a cavitation tunnel. The model-scale measurements are validated against full scale measurements of URN and full scale cavitation observations. The measurements are performed on the chemical tanker M/T Olympus as part of...
In this paper, we present a performance evaluation of two underwater network protocols, named GUWMANET and Dflood. The protocols were tested at sea during the final demonstration of the EDA project Robust Acoustic Communication in Underwater Networks (RACUN). The project started in 2010 with the goal to develop and demonstrate the capabilities of an underwater ad-hoc acoustic network. The trial took...
In this paper authors investigate the problem of predicting the fuel consumption of a vessel in real scenario based on data measured by the onboard automation systems. The goal is achieved by exploiting three different approaches: White, Black and Gray Box Models. White Box Models (WBM) are based on the knowledge of the physical underling processes. Black Box Models (BBMs) build upon statistical inference...
In the context of sea and ocean monitoring from (single polarization) SAR images, an innovative approach in the handling of azimuth ambiguities is here described. The purpose of this paper is to provide a theoretical explanation of the method briefly presented at IGARSS 2013 [1], and suggest applications in coastal and maritime traffic monitoring. The work is developed in the context of the project...
This paper describes a method for evaluating the ship equilibrium point. The ship floating condition is calculated using a FEA-like method (Finite Elements Analysis) on a set of 3D meshes related to the exact 3D geometry of the ship hull and its compartments, the distribution of all weights onboard and/or a damage condition (declared by the operator) and data (automatically acquired by the system)...
There is a rising concern about the environmental status of the seas of our planet. Such concern regards several kinds of anthropogenic activities and their impact on the marine ecosystems. Part of the adverse effects are recognised to be due to various forms of acoustic emissions generated by human activities related to the exploitation of sea resources and to shipping. The main regulatory bodies...
This paper presents spectral analyses of the underwater noise radiated by ships equipped with controllable pitch propellers. The noise measurements were performed at sea for three different ship's types. Each ship passage was characterized by a specific combination of propeller rotational speed and propeller pitch, allowing to investigate the variations of the radiated noise spectrum at different...
The next generation of Autonomous Surface Vessels (ASV) will be optimized for optimum performance at sea. The design of an innovative unconventional SWATH-ASV family, patented by the author and under further investigation at the MIT innovative Ship design lab is described in its main features. The new unconventional design of the hull is the key to superior resistance, powering and seakeeping performance...
Underwater noise is a form of pollution causing significant concern in terms of environmental status. Shipping is considered the main contributor to the total noise at the global scale, since ship radiated noise can propagate up to tens or hundreds of kilometers. This paper reports on a shipping noise prediction tool based on Automatic Identification System (AIS) data and a normal-mode acoustic propagation...
Technology is the key enabler in the effective exploration and exploitation of ocean resources, such as minerals, gas hydrates and ocean energy, which are available in abundance in India. This paper describes the strategic technologies developed by the National Institute of Ocean Technology (NIOT), namely in-situ sea bed soil tester, crawler based polymetallic nodule mining machine, deep water unmanned...
Digital communication at sea in the high north is challenging as the conventionally used geostationary satellite systems operate close to their geographic limits which is around 80 degrees latitude. The only system that provides digital communication capabilities beyond this limitation is Iridium. The MARENOR project has investigated the actual quality of service of communication systems in the high...
Over last ten years Mobile & Marine Robotics Research Centre (MMRRC), University of Limerick, Ireland have developed OceanRINGS — a suite of smart technologies for subsea operations, designed to be integrated with any ROV — ship combination. It includes advanced control solutions for full range of ROVS — from mini ROVs used for remote monitoring & inspection to full-size work-class ROVs. Remotely...
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