Browsing by Author "Chakraborty, B."
Now showing items 1-20 of 92
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A neural network based seafloor classification using acoustic backscatter
Chakraborty, B. (Springer-Verlag; Berlin, Heidelberg, 2002)This paper presents a study results of the Artificial Neural Network (ANN) architectures [Self-Organizing Map (SOM) and Multi-Layer Perceptron (MLP)] using single beam echosounding data. The single beam echosounder, operable ... -
A short discussion on artifact creating conditions using multibeam bathymetric systems in a highly reflecting and smooth bottom
Chakraborty, B. (NIO, Dona Paula, Goa (India), 2000)Using multibeam system, artifact creating conditions are dominant when functioning in highly reflective and flat bottom areas. This simulation study manifests the causes responsible for creating such conditions which ... -
Acoustic characterization of continental shelf seafloor and benthic habitats using single and multi-beam backscatter data
Haris, K.; Chakraborty, B. (Institute of Applied & Computational Mathematics, 2013)Satellite based marine remote sensing is a conventional technique for oceanographic research studies. Likewise, in the future projection application of the acoustic remote sensing using high frequency single-beam echo-sounder ... -
Acoustic characterization of seafloor habitats on the western continental shelf of India
Chakraborty, B.; Mahale, V.; Navelkar, G.S.; Rao, B.R.; Desai, R.G.P.; Ingole, B.S.; Janakiraman, G. (Oxford University Press, 2007)This is a study of the interaction effects of the dual frequency (210 and 33 kHz) backscatter signal with seafloor sediment and benthic biota along a transect in water 27–83 m deep offshore of the Goa region of India’s ... -
Acoustic characterization of seafloor sediment employing a hybrid method of neural network architecture and fuzzy algorithm
De, C.; Chakraborty, B. (IEEE, 2009)Seafloor sediment is characterized acoustically in the western continental shelf of India using the echo features extracted from normal incidence single-beam echo sounder backscatter returns at 33 and 210 kHz. The seafloor ... -
Acoustic seafloor classification: Potential and limitations.
Chakraborty, B. (Fisheries and Marine Institute, 2014) -
Acoustic seafloor sediment classification using self-organizing feature maps
Chakraborty, B.; Kaustubha, R.; Hegde, Amay; Pereira, A. (IEEE, 2001)A self-organizing feature map (SOFM), a kind of artificial neural network (ANN) architecture, is used in this work for continental shelf seafloor sediment classification. Echo data are acquired using an echosounding system ... -
An application of the multibeam sounder for seabed backscattering analysis
Chakraborty, B.; Raju, Y.S.N. (Ultrasonics Society of India, 1994)A theoretical analysis of vertical farfield pattern for a multibeam sounder is performed. The farfield pattern for different steered angles establish the usefulness of present multibeam arrays. An interaction effect of ... -
An experiment towards characterizing seahorse sound in a laboratory controlled environment
Saran, A.K.; Sreepada, R.A.; Chakraborty, B.; Fernandes, W.A.; Srivastava, R.; Kuncolienker, D.S.; Gawde, G. (Department of Electronics and Telecommunication-Goa College of Engineering, 2011)There are many reports of sounds produced by Seahorse (Hippocampus), however, little is known about the mechanism of sound production. Here, we investigate sound produced by the seahorse during feeding. We attempt to try ... -
Analysis of multibeam-hydrosweep echo peaks for seabed characterisation
Chakraborty, B.; Schenke, H.W.; Kodagali, V.N.; Hagen, R. (Springer, 2001)Echo-peak data of outer and normal incidence beams from five different Southern Ocean bottom topographic regions have been analysed. The Rice and Extremal probability density function (PDF) statistical approaches reveal ... -
Application of artificial neural networks to segmentation and classification of topographic profiles of ridge-flank seafloor
Chakraborty, B.; Lourenco, E.; Kodagali, V.N.; Baracho, J. (Indian Academy of Sciences, 2003)In this paper, we have utilized Artificial Neural Networks (ANN) for seafloor topographic data segmentation and roughness classification using the multibeam- Hydrosweep system (installed onboard ocean research vessel Sagar ... -
Application of hybrid techniques (self-organizing map and fuzzy algorithm) using backscatter data for segmentation and fine-scale roughness characterization of seepage-related seafloor along the western continental margin of India
Chakraborty, B.; Menezes, A.A.A.; Dandapath, S.; Fernandes, W.A.; Karisiddaiah, S.M.; Haris, K.; Gokul, G.S. (IEEE, 2015)In this paper, a seafloor characterization technique to unravel the number of data classes using multibeam echo-sounding backscatter data has been demonstrated. An application of self-organizing maps (SOMs) to backscatter ... -
Application of multiplicative array techniques for multibeam sounder systems
Chakraborty, B. (European Acoustics Association, 1994)Multiplicative array processing is well known for its narrow beamwidth and low sidelobe level, but the array gain is quite low. The effectiveness of such a system becomes lower, especially when the signal to noise ratio ... -
Arc arrays: studies of high resolution techniques for multibeam bathymetric applications
Chakraborty, B.; Schenke, H.W. (Elsevier, 1995)In this paper a theoretical study is initiated to observe the utility of directional spectral estimation techniques for `arc array' geometries. We examine the suitability of a 15 degrees arc transducer geometry for multibeam ... -
Backscatter data from the hydrosweep multibeam system: First results
Hagen, R.A.; Chakraborty, B.; Schenke, H.W. (German Hydrographic Society, 1994) -
Bathymetric techniques and Indian Ocean applications
Chakraborty, B.; Fernandes, W.A. (InTech, 2012)The acoustic echosounders are the traditional workhorse of bathymetry measurements. The article highlights the differences between single beam and multibeam echosounders, besides indicating how complimentary they are to ... -
Bathymetry and sediments on the carbonate platform off western India: Significance of Halimeda bioherms in carbonate sedimentation
Rao, V.P.; Mahale, V.; Chakraborty, B. (Springer India, 2018)Bathymetry across the carbonate platform off western India indicated small-size pinnacles and their lateral coalescence into 2 -6-m high mounds landward, and linear elongated carbonate ridges and troughs, mounds and banks ... -
Biodiversity assessment using passive acoustic recordings from off-reef location�Unsupervised learning to classify fish vocalization
Mahale, V.; Chanda, K.; Chakraborty, B.; Salkar, T.; Sreekanth, G.B. (Acoustical Society of America (ASA), 2023)We present the quantitative characterization of Grande Island�s off-reef acoustic environment within the Zuari estuary during the pre-monsoon period. Passive acoustic recordings reveal prominent fish choruses. Detailed ... -
Challenges in marine instrumentation
Afzulpurkar, S.; Desa, E.; Joseph, A.; Chakraborty, B.; Nayak, M.R.; Ranade, G. (Cent. for Earth Sci. Stud., Cochin (India), 1997)The problems of ocean science are technology intensive as the area to be surveyed is vast, complex and hostile. The accessibility of most of the areas too, puts severe constraints on the design methodology, specially the ... -
Characterization of seafloor pockmark seepage of hydrocarbons employing fractal: A case study from the western continental margin of India
Dandapath, S.; Chakraborty, B.; Maslov, N.; Karisiddaiah, S.M.; Ghosh, D.; Fernandes, W.A.; Menezes, A.A.A. (Elsevier, 2012)A quantitative technique is applied to describe the seafloor seepages based on the multi-beam backscatter and bathymetric investigations to characterize the pockmark morphology. The variable seafloor backscatter strength ...