Browsing NTNU Open by Author "Viggen, Erlend Magnus"
Now showing items 1-20 of 20
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A Fast Simulation Method for Ultrasonic Wave Propagation in Coupled Non-parallel Plates
Arnestad, Håvard Kjellmo (Master thesis, 2021)Enkelte systemer i ultralydtesting kan tilnærmes som to ikke-parallelle plater koblet med et fluid, der utstrålende Lamb-bølger brer seg ut i hver plate. Denne oppgaven utvikler en rask og nøyaktig simuleringsmetode for ... -
Acoustic multipole sources for the lattice Boltzmann method
Viggen, Erlend Magnus (Journal article; Peer reviewed, 2013)By including an oscillating particle source term, acoustic multipole sources can be implemented in the lattice Boltzmann method. The effect of this source term on the macroscopic conservation equations is found using a ... -
Acoustic multipole sources from the Boltzmann equation
Viggen, Erlend Magnus (Chapter; Conference object; Peer reviewed, 2013)By adding a particle source term in the Boltzmann equation of kinetic theory, it is possible to represent particles appearing and disappearing throughout the fluid with a specified distribution of particle velocities. By ... -
Automatic interpretation of cement evaluation logs from cased boreholes using supervised deep neural networks
Viggen, Erlend Magnus; Merciu, Ioan Alexandru; Løvstakken, Lasse; Måsøy, Svein-Erik (Peer reviewed; Journal article, 2020)The integrity of cement in cased boreholes is typically evaluated using well logging. However, well logging results are complex and can be ambiguous, and decisions associated with significant risks may be taken based on ... -
Better Automatic Interpretation of Cement Evaluation Logs through Feature Engineering
Viggen, Erlend Magnus; Løvstakken, Lasse; Merciu, Ioan Alexandru; Måsøy, Svein-Erik (Chapter, 2021)We build systems to automatically interpret cement evaluation logs using supervised machine learning (ML). Such systems can provide instant rough interpretations that may then be used as a basis for human interpretation. ... -
Comparison of impulse noise measurements and calculations by noise prediction methods: ISO 9613-2, NMPB-2008, Nord2000 and Harmonoise
Gonzalez, Mary Paula Cruz (Master thesis, 2017)This master s thesis presents a comparison between impulse noise measurements and calculations from four well-known propagation models; ISO 9613-2, NMPB-2008, Harmonoise and Nord2000. The calculated values are compared to ... -
Determining Inner Geometry Properties From Eccentered Pulse-Echo Measurements in a Pipe
Estuariwinarno, Mikael Yuan; Viggen, Erlend Magnus (Chapter, 2021)In the petroleum industry, well integrity evaluation is an essential part of maintaining the safety and sustainability of hydrocarbon production. Ultrasonic pulse-echo cased hole logging is a widely used type of measurement ... -
Enhanced analysis of ultrasonic impedance logs: Improved imaging and fluid channel detection
Hoff, Simon Andreas (Master thesis, 2020)Abstract: The aim of this thesis is to detect vertical features in the the casing cement of oil and gas wells by using pattern recognition techniques based on machine learning on ultrasonic log data. Detecting channels is ... -
Enhanced analysis of ultrasonic impedance logs: Improved imaging and fluid channel detection
Hoff, Simon Andreas (Master thesis, 2020)Målet med denne oppgaven er å detektere vertikale trekk i sementen rundt foringsrøret i olje- og gassbrønner ved å bruke mønstergjenkjenningsteknikker basert på maskinlæring på ultralydloggdata. Å oppdage kanaler er en ... -
A fast semi-analytical method for propagating leaky Lamb wavefields
Arnestad, Håvard Kjellmo; Viggen, Erlend Magnus (Chapter, 2021)A fast method is presented for calculating the wavefields from initialized leaky Lamb waves on plates immersed in sufficiently light fluids. The method works by precomputing the dispersion relation and attenuation, and ... -
Getting started with acoustic well log data using the dlisio Python library on the Volve Data Village dataset
Viggen, Erlend Magnus; Hårstad, Erlend; Kvalsvik, Jørgen (Chapter, 2020)Three issues have long impeded academic research and teaching on well logging. First, real measured data has been hard to come by. This has now been alleviated by Equinor's 2018 release of the Volve Data Village dataset. ... -
Optimising ultrasonic beamforming through solid plates
Åvitsland, Ørjan (Master thesis, 2021)Ultrasoniske verktøy gir en ikke-destruktiv måte å teste integriteten av borehull og sementen som ligger rundt røret. Dagens verktøy tar ikke i bruk dynamisk fokusering, og visse begrensninger på grunn av dette. Å fokusere ... -
Sound Propagation Properties of the Discrete-Velocity Boltzmann Equation
Viggen, Erlend Magnus (Journal article; Peer reviewed, 2013) -
Subjective evaluation of a noise-reduced training target for deep neural network-based speech enhancement
Gelderblom, Femke B.; Tronstad, Tron Vedul; Viggen, Erlend Magnus (Journal article; Peer reviewed, 2018)Speech enhancement systems aim to improve the quality and intelligibility of noisy speech. In this study, we compare two speech enhancement systems based on deep neural networks. The speech intelligibility and quality of ... -
Subjective Intelligibility of Deep Neural Network-Based Speech Enhancement
Gelderblom, Femke B.; Tronstad, Tron Vedul; Viggen, Erlend Magnus (Journal article; Peer reviewed, 2017)Recent literature indicates increasing interest in deep neural networks for use in speech enhancement systems. Currently, these systems are mostly evaluated through objective measures of speech quality and/or intelligibility. ... -
The Lattice Boltzmann Method in Acoustics
Viggen, Erlend Magnus (Conference object, 2010) -
The lattice Boltzmann method with applications in acoustics
Viggen, Erlend Magnus (Master thesis, 2009) -
The lattice Boltzmann method: Fundamentals and acoustics
Viggen, Erlend Magnus (Doktoravhandlinger ved NTNU, 1503-8181; 2014:55, Doctoral thesis, 2014)The lattice Boltzmann method has been widely used as a solver for incompressible flow, though it is not restricted to this application. More generally, it can be used as a compressible Navier-Stokes solver, albeit with a ... -
Understanding sound radiation from surface vibrations moving at subsonic speeds
Viggen, Erlend Magnus; Arnestad, Håvard Kjellmo (Chapter, 2021) -
Viscously damped acoustic waves with the lattice Boltzmann method
Viggen, Erlend Magnus (Journal article; Peer reviewed, 2011)