Domenico Sguerso, Annalisa Azzola, Carlo Nike Bianchi, Bianca Federici, Sara Gagliolo, Carla Morri, Monica Montefalcone
The global increase in seawater temperature is causing irreparable damages to coral reefs all over the world. Frequency of coral bleaching episodes and mass mortality is increasing and coral reefs have not enough time to recover after these impacts. The present study concerns this phenomenon in the context of the Maldives. In this scenario, monitoring activities are very important to check the health of coral reefs, and the adoption of specific parameters such as reef rugosity and accretion of corals provides important measures of the ability of reefs to recover after bleaching. Moreover,...
Rachele Napolitano, Paolo Chiariotti, Enrico Primo Tomasini
This work describes a new method for correcting underwater images acquired under natural illumination condition and targeted to photogrammetry for 3D object reconstruction. In particular, a comparison between the new approach and a previous one from literature is presented. The new approach demonstrated to be a feasible and robust solution to improve quality, colour and contrast in underwater imaging by means of a three-step procedure. The focus of the paper is on 3D reconstruction of small-sized corals in shallow water. The colour of pre-processed images, with a visible green-blue colour...
E. Balestrieri, F. Bonavolontà, E. Caputo, P. Daponte, E. Della Volpe, A. Tedesco
The paper presents a new educational experience capable of merging different approaches such as project-based learning, inquiry-based learning and Science Technology Engineering and Mathematics (STEM) into a students competition to be held at the International Workshop on Metrology for the Sea. The contest is focused on the pollution control and removal by means of autonomous boats capable of achieving and reaching the position of floating rubbish (such as plastic). To accomplish the considered target, contest competitors have to take into account different problems, from boat assembly to...
Simona Saviano, Daniela Cianelli, Enrico Zambianchi, Fabio Conversano, Marco Uttieri
Surface gravity waves retrieved by a network of HF radars and an in situ wave measurement were used to carry out a multiple year characterization of the wave field of the Gulf of Naples. The patterns of the wave fields were in agreement with the wave climatology of the Tyrrhenian Sea. The results highlighted seasonal and interannual consistency in the wave characteristics for a given site, and support the potential of these systems as long-term observatories.
Domenico Maraglino, Mouldi Ben Meftah, Francesca De Serio, Michele Mossa
This work reports the first results of an experimental study aimed at investigating the flow field modified by a hydrofoil NACA 0012 immersed in a water current. The velocity measurements were carried out at the Hydraulic Laboratory of the DICATECh (Polytechnic University of Bari, Italy) using an ADV (Acoustic Doppler Velocimeter) and a PIV (Particle Image Velocimetry) system, in order to reconstruct the flow field and the turbulence characteristics. We obtained instantaneous and average velocity vector maps, as well as instantaneous streamlines maps, in the streamwise direction, in vertical...
Giovanni Pugliano, Umberto Robustelli, Guido Benassai, Diana Di Luccio, Luigi Mucerino
In this paper the comparison between videobased and GPS-derived shoreline measurements was performed on a sandy beach located in the Gulf of Pozzuoli (Italy). The comparison between video camera and DGPS coastline has been carried out measuring the error as deviation from the DGPS line computed along the normal to DGPS itself. The deviations between the two dataset were examined in order to establish possible spatial dependence on video camera point of view in the intertidal zone. The results revealed that, generally, the error increases with the distance from the acquisition system. The...
Beata Palczynska, Romuald Masnicki, Janusz Mindykowski
The article shows the possibilities of using the compressive sensing technique to detect harmonics in a frequency sparse signal. Such features characterize signals in the ship s electrical network. A fast algorithm is presented, in which few randomly sampled projections of the input signal are used for its correct reconstruction. The ℓ1-minimization problem in the compressive signal reconstruction is resolved by means of the convex optimization method with thresholding and the additional use of the K-rank-order filter in the signal s sparse domain in order to accelerate the convergence of...
Enrico Petritoli, Fabio Leccese, Marco Cagnetti
The final aim of this paper is to create peculiar strategies in order to optimise the use platform for underwater scientific research that can accommodate a wide range of different payloads. The main mission profiles and the related employment strategies are optimized, according to the dedicated environment: we will examine in detail the three types of typical mission (pure drift, corrected drift and glider) finally a hybrid one (Jellyfish).
Romuald Masnicki, Janusz Mindykowski
This paper is dedicated to some aspects of maritime on-board safety improvement. Analyzed aspects concern the measurement and control signal transmission on marine environment. The main topic faced by the paper is concentrated on case study-based ZigBee network implementation in the area of the acquisition of data from sensors and measuring transducers connected to the terminal network. The exemplary implementation of ZigBee network, elaborated in Gdynia Maritime University is related, firstly, to the configuration of a simple wireless measurement and control channel, and secondly, to...
Enrico Petritoli, Fabio Leccese
This paper is a section of several preliminary studies of the Underwater Drones Group of the Università degli Studi Roma Tre Science Department. We describe the architecture and features of the Medusa as quasi-Lagrangian AUV and its dual use: a simple emerging buoy or a sub glider.