Ambient noise measurements from an Arctic fjord during summer and winter are analyzed using spectral, coherence, and directionality estimates from a vertically separated pair of hydrophones. The primary noise sources attributed to wind, shipping, and ice activity are categorized and coherence is arrived at. Estimates of the noise field directionality in the vertical and its variation over time and between seasons are used to strengthen the analysis of the time-varying nature of noise sources.
View Article and Find Full Text PDFIn the domain of remote sensing, the classification of hyperspectral image (HSI) has become a popular topic. In general, the complicated features of hyperspectral data cause the precise classification difficult for standard machine learning approaches. Deep learning-based HSI classification has lately received a lot of interest in the field of remote sensing and has shown promising results.
View Article and Find Full Text PDFMar Pollut Bull
December 2021
Sound Pressure Levels were recorded using an Automated Noise Measurement System, during July 2015 - April 2016 at the Kongsfjorden, Arctic. The fjord houses the NyAlesund port and has many vessels plying during summer, which contributes to anthropogenic noise. Spectral distribution and average sound level at 1/3-octave band from 63 Hz to 5000 Hz has been analyzed and correlated with Automatic Identification System marine traffic data.
View Article and Find Full Text PDFIn this study, an analysis of the passive acoustic data is carried out for the quantitative characterization of shallow-water acoustic environments from three major estuarine systems of Goa during the months of March and April. The identification of fish sounds was carried out using waveform and peak power spectral densities (PSDs) of the individual fish calls. Fish sound data showed that the toadfish of the Batrachoididae family (Colletteichthys dussumieri species) produced a spectral level 112.
View Article and Find Full Text PDFOver a 4-year period between 2015 and 2019, in-situ time series measurements of ocean ambient noise over the frequency range 100 Hz to 10 kHz, by an autonomous passive acoustic monitoring system have been made in the Kongsfjorden, Svalbard, Arctic. We characterize the noise due to sea ice melting during winter (December-January). This unique observation reveals loud noise signatures, of the order of 8 dB higher than the background noise, showing the signature of sea ice melting.
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