Browsing Bergen Open Research Archive by Author "Lunde, Per"
Now showing items 1-6 of 6
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Compressional wave phase velocity measurements during hydrate growth in partially and fully water saturated sandstone
Sæther, Mathias Myrtveit; Almenningen, Stian; Ersland, Geir; Lunde, Per (Journal article; Peer reviewed, 2022)The compressional wave phase velocity (cP) has been measured as a function of hydrate saturation (SH) during hydrate growth in Bentheim sandstone. The Fourier spectrum signal processing technique was used to specifically ... -
Finite-Amplitude Power Budget Equations for Acoustic Fish Abundance Estimation
Lunde, Per (Journal article; Peer reviewed, 2020)Finiteamplitude (nonlinear) sound propagation effects in seawater may cause measurement errors in fish and zooplankton abundance estimation and species identification for accessible echo sounder transmit electrical power ... -
Finite-amplitude sound propagation effects in volume backscattering measurements for fish abundance estimation
Pedersen, Audun Oppedal; Lunde, Per; Tichy, Frank; Korneliussen, Rolf (Journal article; Peer reviewed, 2022)Scientific advice for governmental management of marine resources relies on acoustical observation methods. Quantification and identification of fish and plankton species are often achieved using multi-frequency acoustic ... -
Interaction of three-dimensional acoustic beam with fluid-loaded solid plate: Axial near- to far-field transmission at normal beam incidence
Sæther, Mathias Myrtveit; Midtbø, Simen Hammervold; Lunde, Per (Journal article; Peer reviewed, 2022)Axial radiation from leaky Lamb waves propagating in a 6.05 mm water-immersed steel plate being excited by a sound beam normally incident to the plate, is investigated as a function of axial distance, z, and frequency, f, ... -
Power budget equations and calibration factors for fish abundance estimation using scientific echo sounders and sonar systems
Lunde, Per; Korneliussen, Rolf (Peer reviewed; Journal article, 2016-07-09)Acoustic methods used in fish abundance estimation constitute a key part of the analytic assessment that makes the basis for abundance estimation of marine resources. The methods rely on power-budget equations and calibrated ... -
A spectrum-of-spectrum filtering method to extract direct and multipath arrivals from simulations and measurements
Mosland, Eivind Nag; Lunde, Per; Kocbach, Jan Martin (Journal article; Peer reviewed, 2023)In measurements and numerical modelling of wave propagation, undesired interference between direct and multipath arrivals can be reduced using Fourier-based signal processing methods. Existing methods, such as cepstral ...