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The term ldquowave climaterdquo usually refers to the statistical distribution of several oceanographical geophysical variables. Components of the wave climate are variables such as wind velocity, wind direction, significant wave height - SWH, peak period, Tp, mean wave direction, swell SWH, sea SWH, etc. Usually, the classical analysis of the long-term distribution of wave climate is addressed using...
HERMES is an asymmetrical underwater acoustic modem operating in two separate frequency bands. The high data rate uplink operates between 262 kHz and 375 kHz. The downlink is designed for command-and-control and uses a lower frequency band (62-76 kHz) operated at the same source level but at a lower data rate. The acoustic uplink is capable of achieving data rates of 87768 bits-per-second (bps) in...
The paper addresses formal systems verification of autonomous underwater vehicles (AUV). The verification process includes hybrid system modelling and formulation of the discrete representation using natural language programming (sEnglish) via compositional abstraction - employing data, perception and action abstraction methods; the translation of the discrete abstraction into interpreted script programming...
As unmanned marine vehicles rapidly establish themselves as powerful and reliable tools in an ever increasing number of tasks, the focus of research has shifted towards simultaneous operation of coordinated fleets of vehicles. The GREX project joins this development effort with a comprehensive and ambitious development plan. This paper gives account of the first sea trials experience involving a fleet...
The Prestige crisis proved the importance of developing scientific- and application-oriented activities which allow us to improve the oil spill preparedness and response systems having efficient tools to minimize the spill impact in case of an emergency. In this work a methodology has been developed in which oil spill risk is calculated assuming its dependency on the hazard, H, and vulnerability,...
Different solutions are presented to study species in laboratory. The proposed designs used infrared and RFID technology to locate and track the species in the zone of analysis, the data is processed to extract information about their activity and behaviour.
This paper presents a survey and mapping strategy developed and simulated at the University of Idaho (UI). The UI mapping strategy utilizes low-bandwidth acoustic communication to populate and maintain a distributed representation of the search area among a small fleet of autonomous underwater vehicles. Using available acoustic communications, the individual vehicles create a multi-level representation...
In this paper, the preliminary design and evaluation of a real time underwater 3D reconstruction system using multiple sonar views from an acoustic camera are presented. The proposed system which is called Acoustic Stereo Imaging (ASI) consists of two relatively inexpensive acoustic sensors situated above each other with known distance (D) between them. The acoustic sensors are multi-beam, high resolution...
The traditional approach to economic assessment of alternatives in engineering projects has focused in Cost Benefit Analysis (CBA), under this framework several instruments have been developed in order to capture and measure the different effects derived from projects. Although this approach has been generally adopted in public agencies, under the increasing concern on environmental questions a certain...
Robotic platforms are helping marine applications to gain routine and permanent access to the underwater environment. However, challenges related to this domain require the development and integration of more evolved embedded tools that can raise the platform's autonomy levels while maintaining the trust of the operator. This paper shows how knowledge representation, reasoning and planning tools can...
In seafloor seismic observation, the seismometer is usually installed in the seafloor. The data obtained from the seismometer installed in the seafloor is influenced by background noise. In seafloor observation, it is necessary to install seismometer with consideration of influence from installation environment for observation with high accuracy. This paper introduces the past results from seafloor...
This paper describes a process for achieving oil spill detection in satellite images acquired after tanker accidents. These images have been treated with image processing techniques, such us image equalization, image binarization and morphological operations, to obtain the residue segmentation. Once the oil slick is segmented and localized in the image, an active contour is generated around it and...
Morphological changes in coastal areas, especially in river estuaries, are of high interest in many parts of the world. A new X-band radar on board the TerraSAR-X satellite gives access to spatial resolution as fine as 1 m. In Spotlight (SL) mode, resolution is down to 1.7 m in azimuth, with 10 times 10 km coverage. Spotlight is the best choice to monitor river estuaries, river channels, and bathymetry...
This paper describes the integrated marine acoustic controller system (IMACS), a system that provides automated concurrent operation of multiple sonar integrated onto a single survey platform. The system avoids issues of sensor crosstalk by scheduling the transmit-receive cycles through an environmentally adaptive approach in a noninterfering fashion. By dynamically adapting the triggering of the...
In this paper, a front-end of digital receiver with 25 kHz carrier frequency, 5 kHz symbol rate, and any excess-bandwidth of pulse shaping filter is designed using two basic facts. The one is the analog-to-digital converting characteristics that the sampled sequence makes its replicas on the frequency domain and might not be suffered from the aliasing although its sampling rate is lower than the Nyquist...
Evaluation of phytoplankton communities is an important task to characterize marine environments. Fluorescence spectroscopy is a powerful technique usually used for this goal. This study presents a comparison between two different techniques for fast phytoplankton discrimination: Self-Organizing Maps (SOM) and Potential Support Vector Machines (P-SVM), evaluating its capability to achieve phytoplankton...
In connection with intensive ocean development and interrelated expansion of underwater technology (oil and gas production from ocean beds, construction of offshore wind park etc.) problems of high-quality welding and cutting technology take on special significance. One of progressive line of investigation is underwater machine welding by means of filler wire. This article consider possibility of...
A space based receiving system for signals of the automatic identification system (AIS) will extend the coverage of the existing ground network, which is limited to the coastal zone (30-50 nautical miles) to open seas. With newly available satellite-based AIS receivers, the complete global ocean shipping fleet of about 60,000 ships (AIS Class A) can be tracked. The safe processing and distribution...
Oceanic modeling and prediction are highly dependent on the availability of satellite remote sensing and hydrographic in situ measurements to provide reliable and accurate results. In coastal environments the data assimilation is a difficult problem due to the lack of data, the strong coupling between state variables and forcing and the frequent model failures encountered in the modeling. In particular,...
In the beginning of 21 century in addition to existed earlier complex it were appeared anthropogenic influences on resources of Baltic Sea: depressurization of the sinked chemical weapon, increasing of hydrocarbons transport streams and building of large wind power plants stations in the coastal zone and on the sea shelf. In order to estimate their influence on quality of environment we offer to use...
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