### Recent Submissions

• #### Time-Frequency Analysis Meets Quantum Harmonic Analysis ﻿

(Doctoral theses at NTNU;2021:152, Doctoral thesis, 2021)
The subject of this thesis is the study of quantum harmonic analysis and timefrequency analysis, and in particular the intersection of these two fields. Quantum harmonic analysis is studied abstractly both by obtaining new ...
• #### A semi-discrete scheme derived from variational principles for global conservative solutions of a Camassa–Holm system ﻿

(Peer reviewed; Journal article, 2021)
We define a kinetic and a potential energy such that the principle of stationary action from Lagrangian mechanics yields a Camassa–Holm system (2CH) as the governing equations. After discretizing these energies, we use the ...
• #### Twisted Convolution Algebras and Applications to Gabor Analysis ﻿

(Doctoral theses at NTNU;2021:155, Doctoral thesis, 2021)
This thesis concerns several aspects of twisted convolution algebras, with a particular focus on problems arising in Gabor analysis. A significant portion of the thesis is dedicated to the study of Hilbert C -modules known ...
• #### Modelling time to population extinction when individual reproduction is autocorrelated ﻿

(Peer reviewed; Journal article, 2017)
In nature, individual reproductive success is seldom independent from year to year, due to factors such as reproductive costs and individual heterogeneity. However, population projection models that incorporate temporal ...
• #### Tensor-product coaction functors ﻿

(Peer reviewed; Journal article, 2020)
Recent work by Baum et al. [‘Expanders, exact crossed products, and the Baum–Connes conjecture’, Ann. K-Theory 1(2) (2016), 155–208], further developed by Buss et al. [‘Exotic crossed products and the Baum–Connes conjecture’, ...
• #### Inference in cylindrical models having latent Markovian classes - with an application to ocean current data ﻿

(Peer reviewed; Journal article, 2021)
Spatial direction vector data can be represented cylindrically by linear magnitudes and circular angles. We analyze such data by using a hierarchical Markov random field model with latent discrete classes and conditionally ...
• #### Cryptographic Tools for Cloud Security ﻿

(Doctoral theses at NTNU;2021:126, Doctoral thesis, 2021)
• #### Potential and challenges of wind measurements using met-masts in complex topography for bridge design: Part II – Spectral flow characteristics ﻿

(Peer reviewed; Journal article, 2021)
This study quantifies the influence of the local topography on sonic anemometer measurements mounted on tall met-masts deployed in Norwegian fjords. This assessment is done by analysing the second-order structure of ...
• #### The stable category of Gorenstein flat sheaves on a noetherian scheme ﻿

(Journal article; Peer reviewed, 2021)
• #### Minimal semi-flat-cotorsion replacements and cosupport ﻿

(Journal article; Peer reviewed, 2020)
Over a commutative noetherian ring Rof finite Krull dimension, we show that every complex of flat cotorsion R-modules decomposes as a direct sum of a minimal complex and a contractible complex. Moreover, we define the ...
• #### Phenological asynchrony: a ticking time‐bomb for seemingly stable populations? ﻿

(Peer reviewed; Journal article, 2020)
Climate change has been shown to induce shifts in the timing of life‐history events. As a result, interactions between species can become disrupted, with potentially detrimental effects. Predicting these consequences has ...
• #### GANs enabled super-resolution reconstruction of wind field ﻿

(Peer reviewed; Journal article, 2020)
Atmospheric flows are governed by a broad variety of spatio-temporal scales, thus making real-time numerical modeling of such turbulent flows in complex terrain at high resolution computationally unmanageable. In this ...
• #### Mobile Sensing in Substance Use Research: A Scoping Review ﻿

(Peer reviewed; Journal article, 2020)
Background:Addictive disorders and substance use are significant health challenges worldwide, and relapse is a core component of addictive disorders. The dynamics surrounding relapse and especially the immediate period ...
• #### Don’t gamble the COVID-19 response on ecological hypotheses ﻿

(Journal article; Peer reviewed, 2020)
• #### A note on the zeros of approximations of the Ramanujan Ξ−function ﻿

(Peer reviewed; Journal article, 2020)
In this paper we review the study of the distribution of the zeros of certain approximations for the Ramanujan Ξ-function given by Ki (Ramanujan J 17(1):123–143, 2008), and we provide new proofs of his results. Our approach ...
• #### Species distribution models are inappropriate for COVID-19 ﻿

(Journal article; Peer reviewed, 2020)
• #### Instability of the solitary waves for the generalized Boussinesq equations ﻿

(Peer reviewed; Journal article, 2020)
In this work, we consider the following generalized Boussinesq equation \begin{align*} \partial_{t}^2u-\partial_{x}^2u+\partial_{x}^2(\partial_{x}^2u+|u|^{p}u)=0,\qquad (t,x)\in\R\times \R, \end{align*} with $0<p<\infty$. ...
• #### Homotopy categories of totally acyclic complexes with applications to the flat-cotorsion theory ﻿

(Peer reviewed; Journal article, 2019)
We introduce a notion of total acyclicity associated to a subcategory of an abelian category and consider the Gorenstein objects they define. These Gorenstein objects form a Frobenius category, whose induced stable category ...
• #### Bayesian Inversion of Convolved Hidden Markov Models With Applications in Reservoir Prediction ﻿

(Peer reviewed; Journal article, 2019)
The efficient assessment of convolved hidden Markov models is discussed. The bottom layer is defined as an unobservable categorical first-order Markov chain, whereas the middle layer is assumed to be a Gaussian spatial ...
• #### Recollections of V. S. Varadarajan ﻿

(Peer reviewed; Journal article, 2020)
Known to friends, students, and colleagues just as Raja, Veeravalli Seshadri Varadarajan (born May 18, 1937) was a mathematician of Indian origin who made foundational contributions to multiple fields, including probability, ...