## Search

Now showing items 101-200 of 2561

(Research report / Forskningsrapport, 2017)

There are many different numerical methods for solving the Navier-Stokes equations for problems with a free surface. Some examples are volume of fluid (VOF), Marker and cell (MAC), level set, smooth particle hydrodynamics ...

(Master thesis / Masteroppgave, 2017)

The objectives of this thesis have been to model the spot prices in the energy market, to look at the forward curve, and to derive the Greeks from the spread option. The two energy commodities that have been used are power ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2017)

Given an action α of a discrete group G on a unital C∗ -algebra A, we introduce a natural concept of α -negative definiteness for functions from G to A, and examine some of the first consequences of such a notion. ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2017)

For stochastic conservation laws driven by a semilinear noise term, we propose a generalization of the Kružkov entropy condition by allowing the Kružkov constants to be Malliavin differentiable random variables. Existence ...

(Master thesis / Masteroppgave, 2017)

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 ...

(Master thesis / Masteroppgave, 2017)

In this thesis, we study what can be said about Fermat's Last Theorem using only elementary methods. We will study the work of Sophie Germain and Niels Henrik Abel, both who worked with Fermat’s Last Theorem in the early ...

(Journal article / Tidsskriftartikkel / SubmittedVersion, 2017)

We propose and investigate a valuation model for the income of selling tradeable green certificates (TGCs) in the Swedish–Norwegian market, formulated as a singular stochastic control problem. Our model takes into account ...

(Master thesis / Masteroppgave, 2017)

In this thesis we consider sextactic points on plane algebraic curves and a 2-Hessian curve that identifies these points. This curve was first established by Cayley, and we prove that Cayley's 2-Hessian is wrong. Moreover, ...

(Journal article / Tidsskriftartikkel / SubmittedVersion, 2017)

We lift ambit fields to a class of Hilbert space-valued volatility modulated Volterra processes. We name this class Hambit fields, and show that they can be expressed as a countable sum of weighted real-valued volatility ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2017)

We comment on the discretization of the Dirac equation using finite element spaces of differential forms. In order to treat perturbations by low order terms, such as those arising from electromagnetic fields, we develop ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2017)

Stochastic models for forward electricity prices are of great relevance nowadays, given the major structural changes in the market due to the increase of renewable energy in the production mix. In this study, we derive a ...

(Master thesis / Masteroppgave, 2017)

On the 1st of January 2016, the Solvency II Directive regulating the European insurance industry came into force. Along with a host of reporting requirements, quantitative algorithms for calculating key quantities are ...

(Master thesis / Masteroppgave, 2017)

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2017)

We consider the problem of finding a maximum k-regular induced subgraph of a graph G. Theoretical results are established to compare upper bounds obtained from different techniques, including bounds from quadratic programming, ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2017)

An alternating sign matrix , or ASM, is a (0,±1)(0,±1)-matrix where the nonzero entries in each row and column alternate in sign, and where each row and column sum is 1. We study the convex cone generated by ASMs of order ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2017)

In this paper we derive optimal subspaces for Kolmogorov nn-widths in the L2 norm with respect to sets of functions defined by kernels. This enables us to prove the existence of optimal spline subspaces of arbitrarily high ...

(Doctoral thesis / Doktoravhandling, 2017)

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2017)

The algebraic connectivity a(G) of a graph G is an important parameter, defined as the second smallest eigenvalue of the Laplacian matrix of G. If T is a tree, a(T) is closely related to the Perron values (spectral radius) ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2017)

The recent price coupling of many European electricity markets has triggered a fundamental change in the interaction of day-ahead prices, challenging additionally the modeling of the joint behavior of prices in interconnected ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2017)

A well-known application of Malliavin calculus in mathematical finance is the probabilistic representation of option price sensitivities, the so-called Greeks, as expectation functionals that do not involve the derivative ...

Nonlinear interpolatory curve subdivision schemes Restricted Access

(Master thesis / Masteroppgave, 2017)

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 ...

(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2017)

We give recursive formulas for the generating elements in the Milnor basis of the mod 2 motivic Steenrod algebra.
This research was first published in the New York Journal of Mathematics © 2017

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2017)

Let ℓ be a prime and q=pν, where p is a prime different from ℓ. We show that the ℓ–completion of the nth stable homotopy group of spheres is a summand of the ℓ–completion of the (n,0) motivic stable homotopy group of spheres ...

(Chapter / Bokkapittel / SubmittedVersion, 2017)

Electricity infrastructure has become a critical element of modern industrial society. In order to model and analyse this infrastructure, identify weaknesses, and optimize performance, one needs to take into account its ...

(Master thesis / Masteroppgave, 2017)

The traditional, linear representation of the genetic information in populations cause a loss of data, as it can not fully represent sites where the sequences differ. Conversely, a graph may incorporate the variation, ...

(Master thesis / Masteroppgave, 2017)

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 ...

Pricing Freight Derivatives Restricted Access

(Master thesis / Masteroppgave, 2017)

(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2017)

Background
It has been proposed that future reference genomes should be graph structures in order to better represent the sequence diversity present in a species. However, there is currently no standard ...

(Master thesis / Masteroppgave, 2017)

This thesis is devoted to presenting and illustrating a novel estimation method offering a way to reduce confounding bias in time-to-event situations. In order to reduce this bias, without having to observe all of the ...

(Master thesis / Masteroppgave, 2017)

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 ...

(Master thesis / Masteroppgave, 2017)

(Master thesis / Masteroppgave, 2017)

(Master thesis / Masteroppgave, 2017)

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. ...

(Master thesis / Masteroppgave, 2017)

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 ...

(Master thesis / Masteroppgave, 2017)

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2017)

We consider a scalar conservation law with zero-flux boundary conditions imposed on the boundary of a rectangular multidimensional domain. We study monotone schemes applied to this problem. For the Godunov version of the ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2017)

This paper presents an implementation framework for spline spaces over T-meshes (and their d-dimensional analogs). The aim is to share code between the implementations of several spline spaces. This is achieved by reducing ...

(Master thesis / Masteroppgave, 2017)

The main goal of this thesis is to reproduce the article [SW16] by Sims and Williams, categorising the primitive ideal space of the class of Deaconu- Renault groupoid C*-algebras generated by N_0^k-actions. We go through ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2017)

We propose a boundary quotient diagram for right LCM semigroups with property (AR) that generalizes the boundary quotient diagram for N⋊N×. Our approach focuses on two important subsemigroups: the core subsemigroup and the ...

(Research report / Forskningsrapport, 2017)

We consider a Navier-Stokes equation in two and three space dimensions subject to periodic boundary conditions and perturbed by a transport type noise. The perturbation is sufficiently smooth in space, but rough in time. ...

Strong solutions of d-dimensional SDE's with generalized drift and fractional Brownian initial noise

(Journal article / Tidsskriftartikkel / SubmittedVersion, 2017)

In this paper we prove the existence of strong solutions to a SDE with a generalized drift driven by a multidimensional fractional Brownian motion for small Hurst parameters H<1/2. Here the generalized drift is given as ...

(Master thesis / Masteroppgave, 2017)

Detecting fraud using information from social networks Restricted Access

(Master thesis / Masteroppgave, 2017)

With all the technological progress we have witnessed during the last couple of decades, it comes as no surprise that modern fraudsters use highly complex methods to disguise their suspicious activities. Traditional ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2017)

It has recently been demonstrated (Frauendiener and Hennig 2014 Class. Quantum Grav. 31 085010) that the conformally invariant wave equation on a Minkowski background can be solved with a fully pseudospectral numerical ...

Alternative models for reinsurance in Solvency II Restricted Access

(Master thesis / Masteroppgave, 2017)

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2017)

The variational heat equation is a nonlinear, parabolic equation not in divergence form that arises as a model for the dynamics of the director field in a nematic liquid crystal. We present a finite difference scheme for ...

(Journal article / Tidsskriftartikkel / SubmittedVersion; Peer reviewed, 2017)

Skatteetaten bruker i dag prediktive metoder til blant annet utvelgelse til kontroll av merverdiavgiftsoppgaver og til å forbedre og effektivisere innkreving av skatter. Dette har vist seg å gi økt proveny og en mer effektiv ...

(Master thesis / Masteroppgave, 2017)

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2017)

The problem on identification of a limit of an ordinary differential equation with discontinuous drift that perturbed by a zero-noise is considered in multidimensional case. This problem is a classical subject of stochastic ...

(Master thesis / Masteroppgave, 2017)

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 ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2017)

The Lagrangian paths, horizontal Lagrangian drift velocity, U L , and the Lagrangian excess period, T L − T 0 , where T L is the Lagrangian period and T 0 the Eulerian linear period, are obtained by ...

(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2017)

Nocturnal low-level jets (LLJs) are defined as relative maxima in the vertical profile of the horizontal wind speed at the top of the stable boundary layer. Such peaks constitute major power resources for wind turbines. ...

(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2017)

Compound events (CEs) are multivariate extreme events in which the individual contributing variables may not be extreme themselves, but their joint – dependent – occurrence causes an extreme impact. Conventional univariate ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2017)

We present a two-factor option-pricing model, which parsimoniously captures the difference in volatility persistences under the historical and risk-neutral probabilities. The model generates an S-shaped pricing kernel that ...

(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2017)

We study congruences of lines $X_\omega $ defined by a sufficiently general choice of an alternating 3-form $\omega $ in $n+1$ dimensions, as Fano manifolds of index $3$ and dimension $n-1$. These congruences include the ...

(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2017)

In this paper, we are interested by advanced backward stochastic differential equations (ABSDEs), in a probability space equipped with a Brownian motion and a single jump process, with a jump at time τ. ABSDEs are BSDEs ...

(Journal article / Tidsskriftartikkel / SubmittedVersion, 2017)

The attenuation of surface gravity waves is an important process associated with air–sea and wave–current interactions. Here we investigate experimentally the attenuation of monochromatic surface gravity waves due to the ...

(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2017)

In this paper, we study weak solutions to the following nonlinear parabolic partial differential equation ∂tu−diva(x,t,∇u)+λ(|u|p(x,t)−2u)=0inΩT, where λ≥0 and ∂tu denote the partial derivative of u with respect to the ...

(Master thesis / Masteroppgave, 2017)

Målet ved denne artikkelen er å analysere forholdet mellom vri- og flyttespill og symmetrigruppen. Vi skal se sammenhengen mellom gruppeteori og mange populære spill, spesielt når man vil løse spillene

(Master thesis / Masteroppgave, 2017)

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 ...

(Master thesis / Masteroppgave, 2017)

This thesis aims at pricing Contract-for-Difference (CFD) in stock market, and Electricity Price Area Differential (EPAD) in the Nord Pool. For CFD, our model consists of Geometric Brownian Motion and Vasicek process. For ...

(Research report / Forskningsrapport, 2017)

(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2017)

Versatile instruments assembled from off-the-shelf sensors and open-source electronics are used to record wave propagation and damping measured by Inertial Motion Units (IMUs) in a grease ice slick near the shore in ...

(Journal article / Tidsskriftartikkel / SubmittedVersion, 2017)

Traditional programs based on feature engineering are under performing on a steadily increasing number of tasks compared with Artificial Neural Networks (ANNs), in particular for image analysis. Image analysis is widely ...

(Journal article / Tidsskriftartikkel / SubmittedVersion, 2017)

In this paper we construct a new type of noise of fractional nature that has a strong regularizing effect on differential equations. We consider an equation with this noise with a highly irregular coefficient. We employ a ...

(Master thesis / Masteroppgave, 2017)

Environmental contours are used as a basis for e.g., ship designs. The traditional approach to environmental contours is based on the well-known Rosenblatt transformation. However, due to the effects of this transformation ...

(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2017)

Background
We have previously reported a high incidence of colorectal cancer (CRC) in carriers of pathogenic MLH1 variants (path_MLH1) despite follow-up with colonoscopy including polypectomy.
...

(Master thesis / Masteroppgave, 2017)

We consider the bidomain model of cardiac electrophysiology. Departing from a discrete cellular model we derive the bidomain equations by homogenization. Using two-scale convergence we provide a rigorous homogenization ...

(Journal article / Tidsskriftartikkel / SubmittedVersion, 2017)

We study methods for solving stochastic control problems of systems offorward–backward mean-field equations with delay, in finite and infinite time horizon.Necessary and sufficient maximum principles under partial information ...

Topics in Confidence Distributions Restricted Access

(Master thesis / Masteroppgave, 2017)

(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2017)

Landslides are the second-most important cause of tsunamis after earthquakes, and their potential for generating large tsunamis depend on the slide process. Among the world's largest submarine landslides is the Storegga ...

(Master thesis / Masteroppgave, 2017)

(Journal article / Tidsskriftartikkel / SubmittedVersion, 2017)

This paper proposes a Finite Difference Multilevel Monte Carlo algorithm for degener- ate parabolic convection diffusion equations where the convective and diffusive fluxes are allowed to be random. We establish a notion ...

(Master thesis / Masteroppgave, 2017)

(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2017)

Proper orthogonal decomposition (POD) is applied to distinct data sets in order to characterize the propagation of error arising from basis truncation in the description of turbulence. Experimental data from stereo particle ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2017)

We analyse a semidiscrete splitting method for conservation laws driven by a semilinear noise term. Making use of fractional bounded variation (BV) estimates, we show that the splitting method generates approximate solutions ...

(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2017)

We use assembly maps to study TC.AŒG I p/, the topological cyclic homology at a prime p of the group algebra of a discrete group G with coefficients in a connective ring spectrum A. For any finite group, we prove that the ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2017)

We study the concept of financial bubbles in a market model endowed with a set P of probability measures, typically mutually singular to each other. In this setting, we investigate a dynamic version of robust superreplication, ...

(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2017)

The charging of a sounding rocket in subsonic and supersonic plasma flows with external magnetic field is studied with numerical particle‐in‐cell (PIC) simulations. A weakly magnetized plasma regime is considered that ...

(Master thesis / Masteroppgave, 2017)

(Chapter / Bokkapittel / PublishedVersion; Peer reviewed, 2017)

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2017)

An error in [4, Theorem 4.1, 4.5, Corollary 4.5] is corrected. There, in the Monte Carlo error bounds for front tracking for scalar conservation laws with random input data, 2-integrability in a Banach space of type 1 was ...

(Chapter / Bokkapittel / PublishedVersion; Peer reviewed, 2017)

(Chapter / Bokkapittel / PublishedVersion; Peer reviewed, 2017)

(Chapter / Bokkapittel / PublishedVersion; Peer reviewed, 2017)

(Chapter / Bokkapittel / PublishedVersion; Peer reviewed, 2017)

(Master thesis / Masteroppgave, 2017)

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 ...

(Master thesis / Masteroppgave, 2017)

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 ...

(Journal article / Tidsskriftartikkel / SubmittedVersion, 2017)

The directional wave spectra in sea ice are an important aspect of wave evolution and can provide insights into the dominant components of wave dissipation, that is, dissipation due to scattering or dissipation due to ...

(Chapter / Bokkapittel / SubmittedVersion, 2017)

With the shenfun Python module (github.com/spectralDNS/shenfun) an effort is made towards automating the implementation of the spectral Galerkin method for simple tensor product domains, consisting of (currently) one ...

(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2017)

Let GG be an affine group scheme over a noetherian commutative ring RR. We show that every GG-equivariant vector bundle on an affine toric scheme over RR with GG-action is equivariantly extended from Spec ( R ) Spec(R) for ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2017)

We determine the structure of equilibrium states for a natural dynamics on the boundary quotient diagram of C*-algebras for a large class of right LCM semigroups. The approach is based on abstract properties of the semigroup ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2017)

Time change is a powerful technique for generating noises and providing flexible models. In the framework of time changed Brownian and Poisson random measures we study the existence and uniqueness of a solution to a general ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2017)

Compressed sensing is a technique for recovering an unknown sparse signal from a small number of linear measurements. When the measurement matrix is random, the number of measurements required for perfect recovery exhibits ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2017)

The notion of higher order dual varieties of a projective variety, introduced in \cite{P83}, is a natural generalization of the classical notion of projective duality. In this paper we present geometric and combinatorial ...

(Journal article / Tidsskriftartikkel / PublishedVersion, 2017)

Through our work with teaching and learning mathematics at university level, we experience that students can benefit from tips on how to study, and in particular how to study mathematics.
The Department of Mathematics at ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2017)

Using Macaulay’s correspondence we study the family of Artinian Gorenstein local algebras with fixed symmetric Hilbert function decomposition. As an application we give a new lower bound for the dimension of cactus varieties ...

(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2017)

The evolution of interfacial waves on a stratified flow was investigated experimentally for air-water flow in a horizontal pipe. Waves were introduced in the liquid level of stratified flow near the pipe entrance using an ...

(Journal article / Tidsskriftartikkel / SubmittedVersion, 2017)

Simultaneous Particle Image Velocimetry (PIV) measurements of stratified turbulent air/water flow in a horizontal pipe have been performed using water droplets as tracers in the gas-phase. The use of water droplets as ...

Simulating sleep. Restricted Access

(Master thesis / Masteroppgave, 2017)