Now showing items 186-205 of 289

    • Om kvantilregresjon 

      Leknes, Jon Harald (The University of Bergen, 2008)
      Vi skal i denne oppgaven beskrive teorien bak kvantilregresjon. I klassisk regresjonsanalyse bruker man minste kvadraters metode, hvor man beregner betingede gjennomsnittsestimater av forventningen til responsvariabelen. ...
      Master thesis
    • On flow properties of surface waves described by model equations of Boussinesq type 

      Ali, Alfatih Mohammed A. (The University of Bergen, 2012-03-23)
      Doctoral thesis
    • On Semi-implicit Splitting Schemes for the Beltrami Color Image Filtering 

      Rosman, Guy; Dascal, Lorina; Tai, Xue-Cheng; Kimmel, Ron (Springer, 2011-01-15)
      The Beltrami flow is an efficient nonlinear filter, that was shown to be effective for color image processing. The corresponding anisotropic diffusion operator strongly couples the spectral components. Usually, this ...
      Peer reviewedJournal article
    • On Semi-implicit Splitting Schemes for the Beltrami Color Image Filtering 

      Rosman, Guy; Dascal, Lorina; Tai, Xue-Cheng; Kimmel, Ron (Springer, 2011)
      The Beltrami flow is an efficient nonlinear filter, that was shown to be effective for color image processing. The corresponding anisotropic diffusion operator strongly couples the spectral components. Usually, this flow ...
      Peer reviewedJournal article
    • On Solving a Three Phase Flow Model with Capillary Forces 

      Nordhaug, Hans Fredrik (The University of Bergen, 1998-07-10)
      Master thesis
    • On the extension giving the truncated Witt vectors 

      Skjøtskift, Torgeir (The University of Bergen, 2015-01-05)
      We explore the theory of cohomology of groups and the classification of group extensions with abelian kernel. We then look at the group extensions that underlie the truncated Witt vectors on the truncation set {1,p} where ...
      Master thesis
    • On the Formulation of Mass, Momentum and Energy Conservation in the KdV Equation 

      Ali, Alfatih Mohammed A.; Kalisch, Henrik (Springer, 2014-10)
      The Korteweg-de Vries (KdV) equation is widely recognized as a simple model for unidirectional weakly nonlinear dispersive waves on the surface of a shallow body of fluid. While solutions of the KdV equation describe the ...
      Journal article
    • On the use of vertically averaged models to simulate CO2 migration in a layered saline aquifer 

      El-Faour, Basil Fayez (The University of Bergen, 2010-06-01)
      Geologic and flow characteristics such as permeability and porosity, capillary pressure, geologic structure, and thickness all influence and affect CO2 plume distribution to varying degrees. These parameters do not necessarily ...
      Master thesis
    • On weak solutions and a covergent numerical scheme for the compressible Navier-Strokes Equations 

      Svärd, Magnus (SIAM Journal on Numerical Analysis, 2015-02-26)
      In this paper, the three-dimensional compressible Navier-Stokes equations are considered on a periodic domain. We propose a semi-discrete numerical scheme and derive a priori bounds that ensures that the resulting system ...
      Journal article
    • Open-source MATLAB implementation of consistent discretisations on complex grids 

      Lie, Knut-Andreas; Krogstad, Stein; Ligaarden, Ingeborg Skjelkvåle; Natvig, Jostein Roald; Nilsen, Halvor Møll; Skaflestad, Bård (Springer, 2011-08-02)
      Accurate geological modelling of features such as faults, fractures or erosion requires grids that are flexible with respect to geometry. Such grids generally contain polyhedral cells and complex grid-cell connectivities. The ...
      Peer reviewedJournal article
    • Operator splitting methods for systems of convection-diffusion equations: nonlinear error mechanisms and correction strategies 

      Karlsen, Kenneth Hvistendahl; Lie, Knut-Andreas; Natvig, Jostein Roald; Nordhaug, Hans Fredrik; Dahle, Helge K. (Elsevier, 2001)
      Many numerical methods for systems of convection-diffusion equations are based upon an operator splitting formulation, where convective and diffusive forces are accounted for in separate substeps. We describe the nonlinear ...
      Journal articlePeer reviewed
    • Optimal dividend policies for a class of growth-restricted di usion processes under transaction costs and solvency constraints 

      Bai, Lihua; Hunting, Martin; Paulsen, Jostein (Springer Verlag, 2012)
      In this paper, we consider a company where surplus follows a rather general di usion process and whose objective is to maximize expected discounted dividend payments. With each dividend payment there are transaction costs ...
      Peer reviewedJournal article
    • Optimal dividend policies with transaction costs for a class of jump-diffusion processes 

      Hunting, Martin; Paulsen, Jostein (Springer Verlag, 2012)
      This paper addresses the problem of finding an optimal dividend policy for a class of jump-diffusion processes. The jump component is a compound Poisson process with negative jumps, and the drift and diffusion components ...
      Peer reviewedJournal article
    • Optimisation of Production From an Oil-Reservoir Using Augmented Lagrangian Methods 

      Doublet, Daniel Christopher (The University of Bergen, 2008-02-18)
      This work studies the use of augmented Lagrangian methods for water flooding production optimisation from an oil reservoir. Commonly, water flooding is used as a means to enhance oil recovery, and due to heterogeneous ...
      Doctoral thesis
    • Optimization of CO2 Geological Storage Cost 

      Zhu, Sha (The University of Bergen, 2013-12-01)
      Carbon dioxide capture and storage (CCS) is a promising strategy to battle the climate change by injecting large-scale of carbon dioxide back to underground formations and storing the carbon dioxide possibly permanently. ...
      Master thesis
    • Oribatid mites in a changing world 

      De la Riva Caballero, Arguitxu (The University of Bergen, 2011-12-09)
      The main scope of this thesis is to illustrate the validity of oribatid mites as tools for palaeoecological reconstructions. Palaeoecology studies the responses of past organisms to past environmental changes. This ...
      Doctoral thesis
    • Passer og linjal, origami og Galoisteori 

      Vasdal, Thomas Arneberg (The University of Bergen, 2011-06-01)
      Denne oppgaven prøver å belyse konstruksjoner med passer og linjal og origami ved hjelp av Galois- teori. De tre klassiske problemene: Kubens fordobling, sirkelens kvadratur og vinkelens tredeling er sentrale. Oppgaven er ...
      Master thesis
    • A pore network model for calculation of interfacial velocities 

      Nordhaug, Hans Fredrik; Celia, Michael A.; Dahle, Helge K. (Elsevier Science, 2003)
      Two-phase flow in porous media is characterized by fluid-fluid interfaces that separate the fluid phases at the pore scale. These interfaces support pressure differences between phases, and their dynamics allow for ...
      Journal articlePeer reviewed
    • Portfolio Optimization with PCC-GARCH-CVaR model 

      Xi, Linda Mon (The University of Bergen, 2014-06-02)
      This thesis investigates the Conditional Value-at-Risk (CVaR) portfolio optimization approach combined with a univariate GARCH model and pair-copula constructions (PCC) to determine the optimal asset allocation for a ...
      Master thesis
    • Potensialet for dyp geotermisk energi i Norge: Modellering av varmeutvinning fra konstruerte geotermiske system 

      Brun, Knut-Erland (The University of Bergen, 2010-10-05)
      Dette prosjektet tar for seg to ulike modeller for et konstruert geotermisk system; et lukket enkeltbrønn-system og et åpent, sprekkdominert system. Enkeltbrønn-systemet er modellert eksplisitt, og modellen er også tilpasset ...
      Master thesis