• Reactivation of fractures in subsurface reservoirs - A numerical approach using a static-dynamic friction model 

      Berge, Runar Lie; Berre, Inga; Keilegavlen, Eirik (Chapter; Peer reviewed; Journal article, 2019)
      Fluid-induced slip of fractures is characterized by strong multiphysics couplings. Three physical processes are considered: Flow, rock deformation and fracture deformation. The fractures are represented as lower-dimensional ...
    • Reactive Transport in Porous Media 

      Sævik, Pål Næverlid (Master thesis, 2011-08-01)
      In this thesis, we show how the common equations for flow in porous media can be expanded to account for geochemical reactions. Furthermore, the complications arising when solving the new equations numerically are described ...
    • Reconstructing Open Surfaces via Graph-Cuts 

      Wan, Min; Wang, Yu; Bae, Egil; Tai, Xue-Cheng; Wang, Desheng (Journal article, 2011)
      A novel graph-cuts-basedmethod is proposed for reconstructing open surfaces from unordered point sets. Through a boolean operation on the crust around the data set, the open surface problem is translated to a watertight ...
    • Recursions for Convolutions of discrete uniform Distributions revisited 

      Sundt, Bjørn (Statistical report no. 32, Research report, 1997-09)
    • Reducing the domination number of graphs via edge contractions and vertex deletions 

      Galby, Esther; Lima, Paloma T.; Ries, Bernard (Journal article; Peer reviewed, 2021)
      In this work, we study the following problem: given a connected graph G, can we reduce the domination number of G by at least one using k edge contractions, for some fixed integer k>0? We show that for k=1 (resp. k=2), the ...
    • Reexamining CO2 Storage Capacity and Utilization of the Utsira Formation 

      Andersen, Odd; Nilsen, Halvor Møll; Lie, Knut-Andreas (Chapter, 2014)
      In this work we provide estimates of CO2 storage capacity of the Utsira Formation using the recently provided datasets from the Norwegian Petroleum Directorate, taking CO2 density variation into account. We also investigate ...
    • Regresjonsmodeller i skipsforsikring 

      Schei, Ole Johan Sørensen (Master thesis, 2009-09-15)
      Masteroppgaven tar utgangspunkt i et datasett fra skipsforsikring og undersøker hva slags modeller som passer til skadefrekvensen for dette datasettet. Hovedfokuset for masteroppgaven vil være på generalisert lineært miksede ...
    • Rekneark på ungdomstrinnet 

      Johansson, Kari (Master thesis, 2014-06-06)
      Problemstillinga i oppgåva var korleis opplever elevane bruk av rekneark i matematikk på ungdomstrinnet. Gjennom eitt år vart ulike reknearkoppgåver prøvd ut i 9./10. klasse. I etterkant henta eg inn data ved hjelp av ...
    • Relationship between headaches and tinnitus in a Swedish study 

      Lugo, Alessandra; Edvall, Niklas K.; Lazar, Andra; Mehraei, Golbarg; Lopez-Escamez, Jose Antonio; Bulla, Jan; Uhlen, Inger; Canlon, Barbara; Gallus, Silvano; Cederroth, Christopher R (Journal article; Peer reviewed, 2020-05)
      The heterogeneity of tinnitus is likely accounting for the lack of effective treatment approaches. Headaches have been related to tinnitus, yet little is known on how headaches impact tinnitus. We use cross-sectional data ...
    • Renal Function Estimation using Magnetic Resonance Images 

      Schwinger, Eyram A. Kojo (Master thesis, 2009-06-02)
      This study is aimed at testing the use of Magnetic Resonance (MR) images and mathematical models for renal parameter estimation. The study was based on four models; the Patlak model, Cortical Compartment model, Separable ...
    • Report of the NAMMCO-ICES Workshop on Seal Modelling (WKSEALS 2020) 

      Smout, Sophie; Murray, Kimberly; Aarts, Geert; Biuw, Martin; Brasseur, Sophie; Buren, Alejandro; Empacher, Fanny; Frie, Anne Kirstine Højholt; Grecian, James; Hammill, Mike; Mikkelsen, Bjarni; Mosnier, Arnaud; Rosing-Asvid, Aqqalu; Russell, Debbie; Skaug, Hans Julius; Stenson, Garry; Thomas, Len; Ver Hoef, Jay; Witting, Lars; Zabavnikov, Vladimir; Øigård, Tor Arne; Fernandez, Ruth; Wickson, Fern (Journal article; Peer reviewed, 2021)
      To support sustainable management of apex predator populations, it is important to estimate population size and understand the drivers of population trends to anticipate the consequences of human decisions. Robust population ...
    • Reversible Jump Markov Chain Monte Carlo: Some Theory and Applications 

      Lyyjynen, Hannu Sakari (Master thesis, 2014-03-10)
      The history of MCMC, theories of Bayesian thinking and model choice, the Accept- Reject-algorithm, Markov chains, the Metropolis- Hastings-algorithm and the reversible jump MCMC are explained. Then the reversible jump MCMC ...
    • Rigorous estimates on mechanical balance laws in the Boussinesq–Peregrine equations 

      Hussien Elkhorbatly, Bashar; Kalisch, Henrik (Journal article; Peer reviewed, 2024)
      It is shown that the Boussinesq–Peregrine system, which describes long waves of small amplitude at the surface of an inviscid fluid with variable depth, admits a number of approximate conservation equations. Notably, this ...
    • Risk of Leakage versus Depth of Injection in Geological Storage 

      Celia, Michael A.; Nordbotten, Jan Martin; Bachu, Stefan; Dobossy, Mark E.; Court, Benjamin (Peer reviewed; Journal article, 2009-02)
      One of the outstanding challenges for large-scale CCS operations is to develop reliable quantitative risk assessments with a focus on leakage of both injected CO2 and displaced brine. A critical leakage pathway is associated ...
    • Risk stratification in hypertrophic cardiomyopathy. Insights from genetic analysis and cardiopulmonary exercise testing 

      Magri, Damianio; Mastromarino, Vittoria; Gallo, Giovanna; Zachara, Elisabetta; Re, Federica; Piergiuseppe, Agostoni; Giordano, Dario; Rubattu, Speranza; Forte, Maurizio; Cotugno, Maria; Torrisi, Maria Rosaria; Petrucci, Simona; Germani, Aldo; Savio, Camilla; Maruotti, Antonello; Volpe, Massimo; Autore, Camillo; Piane, Maria; Musumeci, Beatrice (Journal article; Peer reviewed, 2020)
      The role of genetic testing over the clinical and functional variables, including data from the cardiopulmonary exercise test (CPET), in the hypertrophic cardiomyopathy (HCM) risk stratification remains unclear. A retrospective ...
    • Robust Control Volume Methods for Reservoir Simulation on Challenging Grids 

      Keilegavlen, Eirik (Doctoral thesis, 2010-02-19)
    • Robust Discretization of Flow in Fractured Porous Media 

      Boon, Wietse; Nordbotten, Jan Martin; Yotov, Ivan (Peer reviewed; Journal article, 2018)
      Flow in fractured porous media represents a challenge for discretization methods due to the disparate scales and complex geometry. Herein we propose a new discretization, based on the mixed finite element method and mortar ...
    • A robust finite element method for Darcy-Stokes flow. 

      Mardal, Kent André; Tai, Xue-Cheng; Winther, Ragnar (Department of Applied Mathematics report, Research report, 2001-01)
    • A robust implicit scheme for two-phase flow in porous media 

      Kvashchuk, Anna (Master thesis, 2015-11-26)
      In this thesis we present a new implicit scheme for the numerical simulation of two-phase flow in porous media. Linear finite elements are considered for the spatial discretization. The scheme is based on the iterative ...