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Information Fusion and Geographic Information Systems, Proceedings of the Fourth International Workshop, IF&GIS 2009, 17-20 May 2009, St. Petersburg, Russia; 01/2009
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ABSTRACT: Pollution detection, environment sensing and appropriate response strategies are important due to the marine ecosystemspsila continuous absorption of pollutants of various origins. Several approaches and techniques of measurements are available for marine environment monitoring including direct sampling, airborne and satellite imagery and underwater acoustics. The huge development in the information technology has provided the possibilities for much faster and more efficient access to survey data, allowing their remote, nearly real-time management, processing and visualisation. The proposed GIS is able to integrate many different types of marine pollution survey data, especially those acquired by various acoustic sensors like Multibeam Sonar Systems (MBSS), echosounder and Side Scan Sonars (SSS). It also supports instantaneous 2D and 3D visualisation in the form of thematic layers that can be overlaid. The system utilises the ArcSDE application server that facilitates storing and managing spatial data (raster, vector, and survey) in a database and ArcGIS Engine GlobeControl and MapControl components for georeferenced presentation of various objects. The set of geoprocessing and spatial analysis methods can be used in order to retrieve relevant information and analysis results.
Information Technology, 2008. IT 2008. 1st International Conference on; 06/2008
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ABSTRACT: High efficiency of multibeam sonar system (MBS) hardware due to operational requirements (i.e. high frequency, high ping rate and high resolution of collected data) results in very large volumes of datasets stored on local hard drives of operatorpsilas station. In this context, the process of archiving of such warehouse of data collected in previous surveys becomes crucial problem. The paper investigates various lossy and lossless compression methods that can be applied to multibeam sonar data to reduce the size of acquired files without loosing relevant information. The specific character of MBS data allows applying various signal, image and video compression methods to achieve better results than when using standard ones. Various techniques of reordering the data were analyzed to achieve best possible compression ratio.
Information Technology, 2008. IT 2008. 1st International Conference on; 06/2008
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ABSTRACT: High efficiency of multibeam sonar system (MBS) hardware due to operational requirements (i.e., high frequency, high ping rate, and high resolution of collected data) results in very large volumes of datasets stored on local hard drives of operator's station. In this context, the process of archiving of such warehouse of data collected in previous surveys becomes crucial problem. The paper investigates various lossy and lossless compression methods that can be applied to multibeam sonar data to reduce the size of acquired files without loosing relevant information. The specific character of MBS data allows applying various signal, image, and video compression methods to achieve better results than when using standard ones. Various techniques of reordering the data were analysed to achieve best possible compression ratio.
The Journal of the Acoustical Society of America 06/2008; 123(5):3781. · 1.55 Impact Factor
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ABSTRACT: The Side Scan Sonar and Synthetic Aperture Sonar are well known echo signal processing technologies that produce 2D images of the seafloor. Both systems combines a number of acoustic pings to form a high resolution image of seafloor. It was shown in numerous papers that 2D images acquired by such systems can be transformed into 3D models of seafloor surface by algorithmic approach using intensity information, contained in a grayscaled images. The paper presents the concept of processing the Side Scan Sonar and Synthetic Aperture Sonar records for detailed reconstruction of 3D seafloor using Shape from Shading techniques. Shape from Shading is one of the basic techniques used in computer vision for the objects reconstruction. The algorithms proposed in the paper use the assumed Lambert model of backscattering strength dependence on incident angle and utilize additionally the information from shadow areas for solving obtained set of equations. The idea was verified by simulation study. The obtained results of 3D shape reconstruction are presented and the performance of the algorithms is discussed.
The Journal of the Acoustical Society of America 06/2008; 123(5):3748. · 1.55 Impact Factor
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ABSTRACT: Contemporary seabed mapping/imaging systems employing processed bottom echo records, acquired by a multi-beam sonar, can map the bottom with the resolution to one meter. However, despite these advantages, even after employing data preprocessing, the method results in an excessive amount of data and the warehouse of petabytes. To address the problem of a compact representation of the huge amount of these raw data and an accurate seabed surface reconstruction from the multibeam sonar records, the paper proposes the data reduction algorithms devel-oped for this purpose. The first one represents the smoothing procedure using B-spline surface obtained from a set of bathymetric 3D data retrieved from the sonar echoes. Whereas, the second one transforms the echo records to the discrete wavelet coefficients domain, and subsequently uses the wavelet shrinkage theory. The second stage in both methods consists of TIN (Triangular Irregular Network) decimation procedure, which reduces the num-ber of polygons in the mesh, while maintaining the sufficient resolution and accuracy of the reconstructed seabed surfaces. Both investigated methods seem to be quite promising tools for significant data reduction and compact representation of seabed 3D images retrieved from the sonar echoes.
01/2002; 88:619-622.
