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Now showing items 1-100 of 2170

(Doctoral thesis / Doktoravhandling, 2020)

Dementia is a growing concern for the health-care in the world and most treatment strategies are not successful. Dementia is associated with accumulation of metabolic waste in the form of protein fragments. Recent breakthroughs ...

(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2019)

Background: Omics data can be very informative in survival analysis and may improve the prognostic ability of classical models based on clinical risk factors for various diseases, for example breast cancer. Recent research ...

(Research report / Forskningsrapport, 2019)

Based on a study of isolated restrained columns, and two-column panel frames, the often complicated mechanics of moment formations in the members are studdied using elastic second-order theory for the purpose of establishing ...

(Research report / Forskningsrapport, 2019)

Columns in sway frames may be divided into laterally ``supporting (bracing) sway columns'', which can resist applied lateral shears, and ``supported (braced) sway columns'', which must have negative shears from the rest ...

(Journal article / Tidsskriftartikkel / SubmittedVersion, 2019)

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2019)

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2019)

We compute the 1-line of stable homotopy groups of motivic spheres over fields of characteristic not two in terms of hermitian and Milnor K-groups. This is achieved by solving questions about convergence and differentials ...

(Journal article / Tidsskriftartikkel / SubmittedVersion, 2019)

We study optimal control of stochastic Volterra integral equations (SVIE) with jumps by using Hida-Malliavin calculus.
We give conditions under which there exist unique solutions of such equations.
Then we prove both a ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2019)

We develop cointegration for multivariate continuous-time stochastic processes, both in finite and infinite dimension. Our definition and analysis are based on factor processes and operators mapping to the space of prices ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2019)

Water wave attenuation by grease ice is a key mechanism for the polar regions, as waves in ice influence many phenomena such as ice drift, ice breaking and ice formation. However, the models presented so far in the literature ...

(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2019)

Appendages of seeds, fruits and other diaspores (dispersal units) are essential for their wind dispersal, as they act as wings and enable them to fly. Whirling fruits generate an auto-gyrating motion from their sepals, a ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2019)

Let G be an undirected simple graph. The signless Laplacian spread of G is defined as the maximum distance of pairs of its signless Laplacian eigenvalues. This paper establishes some new bounds, both lower and upper, for ...

(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2019)

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2019)

Kinetic simulation results are presented to study the response of multi-Needle Langmuir Probes of the type used on many satellites. Simulations of isolated probes are used to parametrize the current collected as a function ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2019)

We present the first application of an Artificial Neural Network trained through a Deep Reinforcement Learning agent to perform active flow control. It is shown that, in a 2D simulation of the Kármán vortex street at ...

(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2019)

Principal component analysis (PCA) is often used in anomaly detection and statistical process control tasks. For bivariate normal data, we prove that the minor projection (the least varying projection) of the PCA‐rotated ...

(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2019)

Objective. Mechanistic modeling of neurons is an essential component of computational neuroscience that enables scientists to simulate, explain, and explore neural activity. The conventional approach to simulation of ...

(Doctoral thesis / Doktoravhandling, 2019)

Teknikker og konsepter som er knyttet til kombinatorikk blir ofte brukt innenalgebraisk geometri. Et eksempel på dette er toriske degenerasjoner, som kanbrukes til å besvare visse klassifiseringsspørsmål. I denne avhandlingen ...

(Doctoral thesis / Doktoravhandling, 2019)

A particular class of Partial differential Equations (PDEs) is the hyperbolic conservation laws which play an instrumental role in numerous real life applications such as synchronization of cardiac pacemakers, traffic flow ...

(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2019)

Volterra processes appear in several applications ranging from turbulence to energy finance where they are used in the modelling of e.g.temperatures and wind and the related financial derivatives. Volterra processes are ...

(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2019)

Excitable biological cells, such as cardiac muscle cells, can exhibit complex patterns of oscillations such as spiking and bursting. Moreover, it is well known that an enhancement in calcium currents may yield certain kind ...

(Doctoral thesis / Doktoravhandling, 2019)

(Doctoral thesis / Doktoravhandling, 2019)

(Journal article / Tidsskriftartikkel / SubmittedVersion, 2019)

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2019)

We consider a stochastic hydroelectric power plant management problem in discrete time with arbitrary scenario space. The inflow to the system is some stochastic process, representing the precipitation to each dam. The ...

(Journal article / Tidsskriftartikkel / SubmittedVersion, 2019)

Several cardiovascular diseases are caused from localised abnormal blood flow such as in the case of stenosis or aneurysms. Prevailing theories propose that the development is caused by abnormal wall shear stress in focused ...

(Journal article / Tidsskriftartikkel / SubmittedVersion, 2019)

The Neumann problem of linear elasticity is singular with a kernel formed by the rigid motions of the body. There are several tricks that are commonly used to obtain a nonsingular linear system. However, they often cause ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2019)

(Journal article / Tidsskriftartikkel / SubmittedVersion, 2019)

(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2018)

Background
Using high-dimensional penalized regression we studied genome-wide DNA-methylation in bone biopsies of 80 postmenopausal women in relation to their bone mineral density (BMD). The women showed ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2018)

In biomedical research, boosting-based regression approaches have gained much attention in the last decade. Their intrinsic variable selection procedure and ability to shrink the estimates of the regression coefficients ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2018)

Given a finite-dimensional Hilbert space H and a collection of operators between its tensor powers satisfying certain properties, we give a short proof of the existence of a compact quantum group G with a fundamental ...

(Doctoral thesis / Doktoravhandling, 2018)

In this PhD thesis problems of Bayesian model selection and model averaging are addressed in various regression contexts. The approaches developed within the thesis are based on the idea of marginalizing out parameters ...

(Doctoral thesis / Doktoravhandling, 2018)

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2018)

The classical maximum principle for optimal stochastic control states that if a control û is optimal, then the corresponding Hamiltonian has a maximum at u=û. The first proofs for this result assumed that the control did ...

(Other / Annet / AcceptedVersion; Peer reviewed, 2018)

We develop a theory of crossed products by actions of Hecke pairs (G, Γ), motivated by applications in non-abelian C ∗ -duality. Our approach gives back the usual crossed product construction whenever G/Γ is a group and ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2018)

Let A be an n × n (0, ∗)-matrix, so each entry is 0 or ∗. An A-interval matrix is a (0, 1)-matrix obtained from A by choosing some ∗’s so that in every interval of consecutive ∗’s, in a row or column of A, exactly one ∗ ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2018)

We investigate the Smith Normal Form (SNF) of alternating sign matrices (ASMs) and related matrices of 0’s and 1’s ((0, 1)-matrices). We identify certain classes of ASMs and (0, 1)-matrices whose SNFs are (0, 1)-matrices. ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2018)

In this paper we show that, with respect to the L2 norm, three classes of functions in Hr(0,1) , defined by certain boundary conditions, admit optimal spline spaces of all degrees ≥r−1 , and all these spline spaces ...

(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2018)

We prove some fundamental results like localization, excision, Nisnevich descent, and the regular blow-up formula for the algebraic K-theory of certain stack quotients of schemes with affine group scheme actions. We show ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2018)

Aims
To the best of our knowledge, there are no systematic reviews or meta‐analyses that compare rasagiline, selegiline and safinamide. Therefore, we aimed to perform a drug class review comparing all available monoamine ...

(Journal article / Tidsskriftartikkel / SubmittedVersion, 2018)

We discuss the internal structure of graph products of right LCM semigroups and prove that there is an abundance of examples without property (AR). Thereby we provide the first examples of right LCM semigroups lacking ...

(Journal article / Tidsskriftartikkel / SubmittedVersion, 2018)

We introduce algebraic dynamical systems, which consist of an action of a right LCM semigroup by injective endomorphisms of a group. To each algebraic dynamical system we associate a C*-algebra and describe it as a semigroup ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2018)

We use Matsui and Takeuchi's formula for toric A-discriminants to give algorithms for computing local Euler obstructions and dual degrees of toric surfaces and 3-folds. In particular, we consider weighted projective spaces. ...

(Chapter / Bokkapittel / AcceptedVersion; Peer reviewed, 2018)

Modulational instability is an efficient mechanism for the generation of rogue waves in the limit of narrow-banded and long-crested wave fields. While such wave fields are easily achieved in laboratories, there appears to ...

(Doctoral thesis / Doktoravhandling, 2018)

Quantum groups are a noncommutative extension of the notion of a group and first appeared in the context of quantum mechanics. Now the theory of quantum groups has further developed and has become interesting in its own ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2018)

This study presents a statistical analysis of interfacial waves in a turbulent stratified air-water flow inside a 10 cm diameter pipe. Wave elevation measurements were acquired using conductance probes with high sampling ...

(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2018)

The multistate reliability theory was applied to the network real-time kinematic (NRTK) data processing chain, where the qualities of the network corrections, baseline residuals, and the associated variance-covariance ...

(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2018)

In this paper, we study strongly robust optimal control problems under volatility uncertainty. In the G-framework, we adapt the stochastic maximum principle to find necessary and sufficient conditions for the existence of ...

(Report / Rapport / SubmittedVersion, 2018)

For large multicomponent systems it is typically too costly to monitor the entire system constantly. In the present paper we consider a case where a component is unobserved in a time interval [0, T]. Here T is a stochastic ...

(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2018)

In this paper, we study the dynamics of a certain Hodgkin-Huxley model describing the action potential (AP) of a cardiac muscle cell for a better understanding of the occurrence of a special type of cardiac arrhythmia, the ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2018)

Multivalency achieves strong, yet reversible binding by the simultaneous formation of multiple weak bonds. It is a key interaction principle in biology and promising for the synthesis of high-affinity inhibitors of pathogens. ...

(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2018)

Stratified air-water flow in a horizontal pipe is investigated experimentally using particle image velocimetry and conductance probes. This flow regime is characterized by a complex interplay between a turbulent airflow ...

(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2018)

This study comprises the analysis and the interpretation of the coherent and the noncoherent parts of a coherent-on-receive microwave radar at grazing incidence conditions. The Doppler measurement is an extension of standard ...

(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2018)

(Chapter / Bokkapittel / AcceptedVersion; Peer reviewed, 2018)

Slippery runways represent a significant risk to aircrafts especially during the winter season. In order to apply the appropriate braking action, the pilots need reliable information about the runway conditions. Unfortunately ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2018)

We introduce a new majorization order for classes (sets) of matrices which generalizes several existing notions of matrix majorization. Roughly, the notion says that every matrix in one class is majorized by some matrix ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2018)

For large multicomponent systems it is typically too costly to monitor the entire system constantly. In the presentpaper we consider a case where a component is unobserved in a time interval [0, T]. The time T is a ...

(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2018)

Wave statistical properties and occurrence of extreme and rogue waves in crossing sea states are investigated. Compared to previous studies a more extensive set of crossing sea states are investigated, both with respect ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2018)

(Chapter / Bokkapittel / AcceptedVersion; Peer reviewed, 2018)

(Journal article / Tidsskriftartikkel / AcceptedVersion, 2018)

We propose a non-Gaussian operator-valued extension of the Barndorff-Nielsen and Shephard stochastic volatility dynamics, defined as the square-root of an operator-valued Ornstein–Uhlenbeck process with Lévy noise and ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2018)

We give a short proof of the convergence to the boundary of Riemann maps on varying domains. Our proof provides a uniform approach to several ad-hoc constructions that have recently appeared in the literature.

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2018)

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2018)

We discuss the internal structure of graph products of right LCM semigroups and prove that there is an abundance of examples without property (AR). Thereby we provide the first examples of right LCM semigroups lacking this ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2018)

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2018)

(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2018)

Extreme wave statistics of unidirectional and counter-propagating seas are investigated, for the special case of long-crested irregular waves, with laboratory experiments and with numerical simulations using the higher ...

(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2018)

The potential and density wake behind a finite-sized object in a magnetized collisionless plasma flow is studied with self-consistent numerical simulations. With increasing magnetization of the plasma, the standard picture ...

(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2018)

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2018)

Powersum varieties, also called varieties of sums of powers, have provided examples of interesting relations between varieties since their first appearance in the 19th century. One of the most useful tools to study them ...

(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2018)

We solve affirmatively the homotopy limit problem for (effective) -theory over fields of finite virtual cohomological dimension. Our solution uses the motivic slice filtration and the first motivic Hopf map.

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2018)

We investigate the effect of waves on the airflow in horizontal two-phase pipe flow. Velocity fields in the gaseous phase were acquired by particle image velocimetry (PIV), while interfacial elevation was measured with ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2018)

Wave impact on a vertical wall has been investigated in a physical and numerical wave tank. Two different impact phenomena were explored. A flip-through, where the front face of the wave was moving rapidly vertical due to ...

(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2018)

(Chapter / Bokkapittel / AcceptedVersion; Peer reviewed, 2018)

The main idea of this paper is to use the notion of buffered failure probability from probabilistic structural design, first introduced by Rockafellar & Royset (2010), to introduce buffered environmental contours. Classical ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2018)

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2018)

If a number of candidate variables are available, variable selection is a key task aiming to identify those candidates which influence the outcome of interest. Methods as backward elimination, forward selection, etc. are ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2018)

We study the Whitehead torsion of inertial h-cobordisms, continuing an investigation started in [12]. Of particular interest is a nested sequence of subsets of the Whitehead group, and a number of examples are given to ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2018)

(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2018)

We model the logarithm of the spot price of electricity with a normal inverse Gaussian (NIG) process and the wind speed and wind power production with two Ornstein–Uhlenbeck processes. In order to reproduce the correlation ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2018)

We prove uniqueness of representations of Nica–Toeplitz algebras associated to product systems of C∗-correspondences over right LCM semigroups by applying our previous abstract uniqueness results developed for C∗-precategories. ...

(Doctoral thesis / Doktoravhandling, 2018)

A simplicial set is said to be non-singular if its non-degenerate simplices are embedded. Let sSet denote the category of simplicial sets. We prove that the full subcategory nsSet whose objects are the non-singular simplicial ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2018)

The continuous-time version of Kyle [(1985) Continuous auctions and insider trading, Econometrica53 (6), 1315–1335.] developed by Back [(1992) Insider trading in continuous time, The Review of Financial Studies5 (3), ...

(Journal article / Tidsskriftartikkel / SubmittedVersion, 2018)

Generalized linear mixed models (GLMM) are used for inference and prediction in a wide range of different applications providing a powerful scientific tool. An increasing number of sources of data are becoming available, ...

(Journal article / Tidsskriftartikkel / AcceptedVersionAcceptedVersion; Peer reviewed, 2018)

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2018)

We extend the Heston stochastic volatility model to a Hilbert space framework. The tensor Heston stochastic variance process is defined as a tensor product of a Hilbert-valued Ornstein–Uhlenbeck process with itself. The ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2018)

The paper addresses projected changes of wave climate in the North Atlantic and their impact on the safe design of ships, with a particular focus given on associated uncertainties. The Fifth Assessment Report of the ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2018)

We derive and study a Lax–Friedrichs-type finite volume method for a large class of nonlocal continuity equations in multiple dimensions. We prove that the method converges weakly to the measure-valued solution and converges ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2018)

In this paper, we show how to approximate Heath–Jarrow–Morton dynamics for the forward prices in commodity markets with arbitrage-free models which have a finite-dimensional state space. Moreover, we recover a closed-form ...

(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2018)

The properties of directional distributions in ocean wave spectra are studied, with an emphasis on sea states with bimodal directional distributions in the high-frequency tails of single-peaked wave systems. A peak-splitting ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2018)

We study how the geometry of a projective variety X is reflected in the positivity properties of the diagonal ΔX considered as a cycle on X×X. We analyze when the diagonal is big, when it is nef, and when it is rigid. In ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2018)

On reduced twisted group C*-algebras that are simple and/or have a unique trace

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2018)

(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2018)

Knowledge about how information is stored in neurons of animals and in the human brain is still incomplete. A hypothesis related to long-term changes in synaptic efficiency has strong experimental support, but does not ...

(Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2018)

Two-phase dispersed and slug flows in a pipe are investigated using proper orthogonal decomposition (POD). The data are acquired through tomographic reconstruction of X-ray measurements, where holdup, cross-sectional phase ...

(Chapter / Bokkapittel / PublishedVersion; Peer reviewed, 2018)

Most of today’s Machine Learning (ML) methods and implementations are based on correlations, in the sense of a statistical relationship between a set of inputs and the output(s) under inves- tigation. The relationship might ...

(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2018)

Atlantic cod (Gadus morhua) provides an interesting species for the study of host-microbe interactions because it lacks the MHC II complex that is involved in the presentation of extracellular pathogens. Nonetheless, little ...

(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2018)

We prove that the sequential functionals of some fixed types at type level 2, taking finite sequences of unary functions as arguments, do form a directed complete partial ordering. This gives a full characterisation of for ...

(Chapter / Bokkapittel / AcceptedVersion; Peer reviewed, 2018)

We identify a number of decidable and undecidable fragments of first-order concatenation theory. We also give a purely universal axiomatization which is complete for the fragments we identify. Furthermore, we prove some ...