Browsing NTNU Open by Author "Viggen, Erlend Magnus"
Now showing items 1-20 of 27
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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, 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 ... -
Assisted Cement Log Interpretation Using Machine Learning
Viggen, Erlend Magnus; Singstad, Bjørn Jostein; Time, Eirik; Mishra, Siddharth; Berg, Eirik (Peer reviewed; Journal article, 2022)The Assisted Cement Log Interpretation Project has used machine learning (ML) to create a tool that interprets cement logs by predicting a predefined set of annular condition codes used in the cement log interpretation ... -
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. ... -
Better Automatic Interpretation of Cement Evaluation Logs through Feature Engineering
Viggen, Erlend Magnus; Løvstakken, Lasse; Måsøy, Svein-Erik; Merciu, Ioan Alexandru (Journal article; Peer reviewed, 2021)We investigate 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 ... -
Doppler ultrasound for quantification of fluid influx/ efflux from borehole fractures using LWD tools
Indimath, Shivanandan (Doctoral theses at NTNU;2024:221, Doctoral thesis, 2024)The work presented in this thesis is aimed at studying the potential for applying ultrasonic Doppler measurements during a borehole drilling process using ultrasonic logging-while-drilling (LWD) tools. The primary intention ... -
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. ... -
Inhomogeneous P- and S-wavefields radiated into isotropic elastic solids
Viggen, Erlend Magnus; Arnestad, Håvard (Chapter, 2022)A vibrating surface in contact with a solid material will generate P- and S-waves in the solid. When the surface vibration is spatially attenuated, we must take into account that the generated waves are always inhomogeneous. ... -
Modelling acoustic radiation from vibrating surfaces around coincidence: Radiation into fluids
Viggen, Erlend Magnus; Arnestad, Håvard (Peer reviewed; Journal article, 2023)It is well-known that vibrating surfaces generate sound waves in adjacent fluids. According to the classical radiation model, the nature of these waves depends on whether the vibration’s phase speed cv is above (supersonic) ... -
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 ... -
Pyintegrity: An Open-Source Toolbox for Processing Ultrasonic Pulse-EchoWell Integrity Log Data
Viggen, Erlend Magnus; Diez, Anja; Johansen, Tonni Franke (Journal article, 2024)Many companies offer similarly designed wireline tools using ultrasonic pulse-echo measurements toevaluate barrier integrity in cased-hole wells. While these tools provide very similar data, differentcompanies process their ... -
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 ...