• Elastodynamic full waveform inversion on GPUs with time-space tiling and wavefield reconstruction 

      Aaker, Ole Edvard; Raknes, Espen Birger; Arntsen, Børge (Peer reviewed; Journal article, 2020)
      Full waveform inversion (FWI) is a procedure used to determine the elastic parameters of the Earth by reducing the misfit between observed elastodynamic wavefields and their numerically modelled counterparts. The numerical ...
    • Imaging of Subsurface Injectite Structures 

      Estenstad, Ådne Gimse (Master thesis, 2019)
      Arbeidet i denne masteroppgaven har fokusert på seismisk avbildning av injektittstrukturer. Disse strukturene har en ikke-uniform geometri som kan gjøre avbildning utfordrende. Interesseområder for denne masteroppgaven inkluderer; ...
    • Seismic wave modelling on GPU clusters 

      Pedersen, Anders Solberg (Master thesis, 2019)
      Vi utvikler et program for å simulere seismiske bølger på GPU-klynger ved hjelp av CUDA og MPI. Ved å bruke spektralelementmetoden til å løse den elastiske bølgelikningen i 3D kan problemet paralleliseres og løses effektivt. ...
    • Three Dimensional Elastic Full Waveform Inversion 

      Raknes, Espen Birger (Doctoral thesis at NTNU;2015:212, Doctoral thesis, 2015)
      The full waveform inversion (FWI) method is a technique for estimating subsurface elastic parameters using inverse theory. FWI is formulated as an optimization problem that seeks to minimize the dissimilarities between ...
    • Towards Fine-Grained Dynamic Tuning of HPC Applications on Modern Multi-Core Architectures 

      Sourouri, Mohammed; Raknes, Espen Birger; Reissmann, Nico; Langguth, Johannes; Hackenberg, Daniel; Schöne, Robert; Kjeldsberg, Per Gunnar (Chapter, 2017)
      There is a consensus that exascale systems should operate within a power envelope of 20MW. Consequently, energy conservation is still considered as the most crucial constraint if such systems are to be realized. So far, ...
    • Wavefield reconstruction for velocity–stress elastodynamic full-waveform inversion 

      Aaker, Ole Edvard; Raknes, Espen Birger; Pedersen, Ørjan; Arntsen, Børge (Peer reviewed; Journal article, 2020)
      Gradient computations in full-waveform inversion (FWI) require calculating zero-lag cross-correlations of two wavefields propagating in opposite temporal directions. Lossless media permit accurate and efficient reconstruction ...