The timing of cardiac events is essential for the analysis of certain components of myocardial function [36]. Finding an algorithm that detects these timings has therefore been the subject of several studies[36]. In this ...

Recommender systems are algorithms that suggest content or products to users on the internet. These are becoming ever more important due to the massive growth of content on popular web sites, yet their design is often only ...

Modeling of the blood flow in and around aneurysms with computational fluid dynamics (CFD) is important to better understand why aneurysms form and rupture. CFD modeling requires an accurate representation of the ...

This graduate thesis has been devoted to the examination of spectral methods. The object of the research is to analyse the accuracy and precision of different numerical schemes developed on the basis of mathematical models ...

Compressed sensing is the study of solving underdetermined systems of linear equations with unique sparse solutions. In addition to this, applications of compressed sensing require that the number of rows of the measurement ...

Applying the computational fluid dynamics software openFoam, we study dead water resistance on a barge. Dead water resistance is the extra drag due to internal waves in the interface between salt water and fresh water. For ...

Ventricular fibrillation (VF) occurs in ~10 % of myocardial infarction (MI) patients. These patients have higher in-hospital mortality and increased risk to lethal arrhythmias. The susceptibility for VF during acute MI and ...

The field of compressive sensing is a modern field in applied mathematics which receives a lot of attention. In this thesis, we will give some insight into the iterative algorithms used in compressive sensing. We will study ...

Computational fluid dynamics, with the software OpenFOAM, has ben used to investi- gate the dead water phenomenon. Investigation was done by simulating a barge moving in stratified waters. Comparison of the turbulence ...

The bidomain and monodomain models describing cardiac electrophysiology are computationally demanding to solve. Employing efficient numerical methods is therefore important for the practical use of these models. In this ...

Conventional 2D medical ultrasound imaging is based on analyzing the backscatter (echoes) from multiple, focused, transmitted acoustic beams. Most imaging systems are very similar in the way they create and record beams. ...

The aim of this thesis is to study the convergence and smoothness of certain nonlinear interpolatory curve subdivision schemes. The emphasis will be on the iterated geometric schemes, which are extensions of the nonlinear ...

Computational models of fluids, structures, and the interaction between them shows good promise in science and engineering, with nearly infinitely many applications. However, fluid-structure interaction (FSI) is poorly ...

Millions of people world wide suffer from asthma, and respiratory diseases are one of the leading causes of death. Patients can be treated or relieved by inhalation of medicine, but the efficiency of the treatment is often ...

The mechanical behavior of the heart has been modeled for decades by using continuum mechanics and numerical methods. A widely used, but rarely discussed, assumption is that inertial effects can be neglected in these models. ...

OpenFOAM and FEniCS are two solver frameworks for solving computational fluid dynamics problems. The former employs the finite volume method to discretize the governing equations, while the latter employs the finite element ...

Muscle ultrasound imaging is a convenient technique to visualize normal and pathological muscle tissue. Studying muscle fascicle pennation angle and fascicle length and their dynamic changes during contraction are important ...

In the recent decade, artificial intelligence and machine learning has become increasingly popular for solving complex real-world problems. In particular problems which was believed to be very hard or in some cases impossible ...

Parametric representations of surfaces in Computer-Aided Geometric Design (CAGD) are often based on connected patches with rectangular parameter domains. Given a loop of four space curves and normal-derivative curves, we ...

This thesis investigates the appliance of the finite element method to long wave propagation in channels. Weak formulations of potential- and velocity based Boussinesq equations were derived, with the normal dependent ...

In this thesis results from numerical simulations of long wave run-up on composite beaches are presented along with the analytical solution to the linear problem. The purpose of this study is to find out which parts of the ...

CFD analysis of a cone grid applied to a flat plate, with mesh generation script.

This master thesis presents a laboratory investigation of wave slamming forces on a vertical cylinder in deep and intermediate water. The technique of frequency focusing of the incoming wave field allows for generation of ...

We have used the level - set function to divide a computational domain into a solid region and a fluid region to create an idealized model of blood flow in narrow cerebral arteries to simulate the mechanotransduction in ...

This thesis presents an experimental investigation on the occurrence of freak waves in a bimodal sea. The bimodal sea consisted of two wave systems traveling in the same direction, with different peak frequencies f_{Pj} ...

Avhandlingen er en del av en større forskning på bimodal sjø. Det er gjort eksperimenter med vindsjø sammen med dønnning, samt bikromatisk bølge bestående av en kort bølge ridende på dønning er genrert i bølgetanken. Det ...

An important aspect in portfolio optimization is the quantification of risk. Variance was the starting point, as proposed by Harry Markowitz in the 1950’s, but it’s obviously flawed since it measures high returns as risk. ...

Syringomyelia is a progressive disease where fluid filled cavities develop inside the spinal cord, and is frequently seen together with Chiari Malformation I (CMI). CMI is characterized by downwards displacements of the ...

Brain aneurysms are focalized diseased blood vessels, often shaped like a balloon, which can rupture and cause bleeding in the brain. The presence of aneurysms is correlated with internal carotid artery (ICA) extracranial ...

Traditionally the compressive sensing theory have been focusing on the three principles of sparsity, incoherence and uniform random subsampling. Recent years research have shown that these principles yield insufficient ...

The numerical solution of differential equations is an algorithmic process with various parameters controlling the accuracy, stability and computational time of the simulation. In Computational Fluid Mechanics (CFD) there ...

One of the challenges related to modelling calcium dynamics in cardiac cells is the large difference in the length scales involved. The dyad, where important processes take place, is very small compared to the whole cell. ...

The intention of this thesis is to give a better understanding of the way that subduction zones evolve, to examine the way that different subduction parameters affect each other and finally to demonstrate how visualization ...

Tynne, porøse plater, oskillerende eller holdt fast under påvirkning av en innkommende bølge, er studert. Bølgen vandrer på et fluid som er antatt inkompressibelt og irrotasjonelt, og lineær potensialteori anvendes. Uttrykk ...

Bølgeinduserte strømninger og bølgedempingsrater for ulike overflate-dekker er undersøkt ved hjelp av PIV og ultralydmålere. To økter med eksperimenter av mekanisk genererte monokromatiske bølger som forplanter seg i en ...

Metagenomics is the investigation of genetic samples directly obtained from the environment. Driven by the rapid development of DNA sequencing technology and continuous reductions in sequencing costs, studies in metagenomics ...

Studiet undersøker muligheten for å bruke Steamline Upwind/Petrov Galerkin (SUPG) og Discontinuous Galerkin (DG) i adveksjons-dominert skalar-blanding med høyt Schmidt-tall. Forenklede tester viste at DUPG og DG gir dårlig ...

Det er betraktet to rektangulære geometrier på en fri overflate i 2-D. Når geometriene er adskilt med en liten spalteavstand kan det oppstå stor vertikal bevegelse av væsken. Vanlige lineære sea keeping programmer ...

The aim of this work has been to implement a range of Large Eddy Simulation (LES) turbulence models into Oasis, a Computational Fluid Dynamic (CFD) solver for incompressible flows based on the Finite Element method (FEM), ...

Consider a random walk on an undirected, connected graph. On each edge we can set a transition probability to connect two adjacent vertices. The mixing rate of the associated Markov chain to the uniform equilib- rium ...

Geodesiske linjer og hyperstrømlinjer er brukt for å visualisere andre ordens tensorer. Dessuten ser vi på en ny måte å fremstille andreordens tensorfelt på. Ved å bruke retning til geodesiske linjer i steden for egenvektorer, ...

Reaction-Diffusion equations arise in many models in biomedical computing. One of these areas are models for the calcium dynamic in the heart cells. As the terms in reaction-diffusion equations can be solved separately ...

Resonant behaviour in the gap between two adjacent bodies on a free surface is investigated numerically. The study is done within the framework of two-dimensional potential theory. It is of common conception that traditional ...

The electrical activity in the Purkinje network and the myocardial tissue in the ventricles of the human heart was modeled. The focus was on the Purkinje tree and the coupling of the Purkinje network and the myocardium. ...

In a subsea facility, the pipelines will be surrounded by sea water at 4◦C, which will actively cool the production fluid inside. If temperatures drop below a critical value, water and gas will form unwanted solids called ...

This master thesis presents an experimental study of plunging breakers on a beach with a slope of 5.1◦. The incoming waves are solitary waves with various amplitudes, and the areas investigated are the swash zone and the ...

The parameter dependent Brinkman equation can be used to model viscous and porous flow. The equation covers a family of problems, ranging from the Stokes problem to the Darcy problem. We apply the stabilization methods; ...

Målet med oppgaven er å undersøke isomorfier mellom visse Heisenberginvariante variteter eller finne ut når to slike er isomorfe.

A short introduction to the Nitsche method is given for the overlapping meshes case. Several algorithms for collision detection and mesh decomposition are reviewed and implemented, and a greedy triangulation routine is ...

Given today s limited capacity at airports, and the continuous increase in air transportation, the need for new ways to handle airport logistics will soon be needed. The task of managing arriving and departing flights is ...

A key challenge in Air Traffic Management (ATM) is to provide a schedule with high throughput on the runways, and at the same time meet objectives connected to taxiing times and punctuality while ensuring safe operations ...

The one-shot method is an approach to solve PDE-constrained optimization problems. In this thesis we study two models describing the deformation of biological tissue due to harmonic acoustic waves. These models are the ...

This work presents a theoretical and experimental investigation on the statistical properties of the surface elevation in a special case of crossing sea conditions. The special case considered is the case of two irregular ...

The main objective of this master thesis was to experimentally investigate the boundary layer under a solitary wave. Experiments of solitary waves on constant depths were conducted, varying the amplitude in order to ...

Det er kjent både fra eksperimentelle og numeriske resultater, at langkammede bølger som propagerer på grunt vann over en plan variabel bunn mot grunnere vann, har større sannsynlighet for freake bølger ved den grunne delen ...

In their paper, "Type III sigma-spectral triples and quantum statistical mechanical systems", M. Greenfield, M. Marcolli and K. Teh used the Bost-Connes system to construct a type III sigma-spectral triple where the twisting ...

This paper is about solving an optimization problem for a sparse solution. Given a matrix A and a vector b, the optimization problem is to solve the linear equation Ax = b for x. The problem can be represented as a ...

Oppgaven tar for seg den seismiske bølgeligningen i et og to lag med materialer ved hjelp av endelige differanser i tid, og ved bruk av elementmetoden for romlige koordinater. Oppgaven er delt i en serie prosjekter som tar ...

The first part of this thesis will build up an overview of a small section of the field of subdivision, namely binary univariate schemes. Since most of the theory on subdivision is based on a uniform spacing of the initial ...

Introduction: An aneurysm is an acquired, abnormal dilation of a blood vessel. Computational fluid dynamics (CFD) have been used to try and understand this phenomena. CFD studies use assumptions in the simulation model and ...

Denne oppgaven beskriver en automatisk algoritme for å koble sammen AIS-data, Automatic Identification System, med en eksisterende algoritme for å detektere oljesøl i SAR-bilder, Synthetic aperture radar. AIS er et system ...

Cylindrical shells are common configurations within the technology. The transition from the side to the bottom on a ship has the shape of a fourth of a cylindrical shell. Both ring and stringer stiffeners can be added to ...

Dimensjonering for jordskjelv har etter innføringen av Eurokodene blitt et mer aktuelt tema i Norge. NS-EN 1998-1:2004+NA:2008 Eurokode 8: Prosjektering av konstruksjoner for seismisk påvirkning Del 1: Allmenne regler, ...

Formålet med denne rapporten er å utlede og vurdere mulighet for bruk av en teoretisk metode som baserer seg på anvendelse av en konseptuel beregningsparameter, ekvivalent initial sprekkdybde (EIFS), i den tradisjonelle ...

Image enhancement has many applications. This thesis is devoted to image inpainting, which is to fill in the corrupted or missing pixels in a meaningful way. These pixels may be deteriorated or missing for various reasons, ...

Fenomenene utilsiktede deformasjoner og skjærriss har en spesiell tendens til å oppstå i fritt frambygg bruer, og har de siste tiårene tiltrukket seg stor oppmerksomhet blant bruaktører både i Norge og resten av verden. ...

The main objective of the present thesis was to study how composite patches can reduce the stress intensity in cracked steel plates, and how these patches, by reducing the stress intensity, can limit the extent of fatigue ...

The purpose of this thesis is to perform some mathematical analysis and study numerical solutions of different models describing (different aspects of) axonal transport. We will explain our numerical results using mathematical ...

Motivation for the thesis is the vortex induced vibrations (VIV). To predict the fatigue life of an offshore cable subjected to VIV, the eigen frequencies of the system need to be known for the configuration of a cable ...