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Model and Data Diagnosis under Limited Supervision in Modern AI
(Doctoral thesis; Doktorgradsavhandling, 2024-12-13)Deep Learning in modern Artificial Intelligence (AI) has witnessed unprecedented success on a variety of domains over the past decade, ranging from computer vision to natural language reasoning tasks. This success is owed primarily to the availability of large, annotated datasets, the existence of powerful mathematical models, and the mechanism to train large models on such data with advanced resources ... -
Intermittent fluctuations at the boundary of magnetically confined plasmas
(Doctoral thesis; Doktorgradsavhandling, 2024-11-29)This thesis presents a comprehensive analysis of a stochastic model for transport due to the motion of uncorrelated localized structures. The motivation for this model is found in the scrape-off layer (SOL) of magnetically confined plasmas, but its applicability extends to other turbulent or chaotic systems. This model provides a statistical framework to explore the implications of different transport ... -
Epidemiology Network Analysis
(Doctoral thesis; Doktorgradsavhandling, 2024-11-29)<p><i>Research questions</i> The primary objective of this doctoral dissertation is an explorative investigation into the social network dynamics within eight high schools, located in Tromsø and Balsfjord (North Norway), and the extent to which these dynamics contribute to the overall health and well-being of the students, such as in the context of infectious disease spread and the transmission of ... -
Near-optimality and robustness in energy systems modelling
(Doctoral thesis; Doktorgradsavhandling, 2024-11-27)<p>To avert a climate disaster, the global energy system quickly needs to transition to net-zero emissions. This will involve drastic reductions in the use of fossil fuels on one hand and electrification based on renewable energy on the other hand. Research has shown that the transition is technically feasible, but presents us with difficult trade-offs and compromises. Since renewable energy is more ... -
Visible light-mediated alkyl radical additions to alkenyl and alkynyl silanes
(Doctoral thesis; Doktorgradsavhandling, 2024-11-15)<p>Radicals are reactive species that possess a unique reactivity, which enables them to form unusual bonds unreachable by ionic chemistry. In the last twenty years, radical chemistry has benefited from a renewed interest due to the emergence of methods that can initiate radical reactions under mild conditions. Among those, visible light-mediated radical chemistry has become established as a powerful ... -
Computational Approach to Molecular Reactivity of Transition Metal Complexes
(Doctoral thesis; Doktorgradsavhandling, 2024-10-25)<p>Transition metal (TM) catalysts are indispensable in industrial operations and organic synthesis due to their unique properties, such as variable oxidation states, rich coordination chemistry, and ability to enable electron transfer processes. These properties allow them to activate a diverse range of substrates by lowering activation energies, and the catalysts can be fine-tuned to enhance chemo-, ... -
Understanding Inner Solar System Dust Environment Through In-Situ Measurements
(Doctoral thesis; Doktorgradsavhandling, 2024-10-04)It is apparent from remote observations that the density of interplanetary dust is the highest in the near-solar region. Yet, there were little in-situ data available from measurements from within 1 AU before Parker Solar Probe (PSP) and Solar Orbiter (SolO) missions. They both venture close to the Sun on elliptical orbits, and they are equipped with electrical antennas capable of dust detection, ... -
Pre-Last Glacial Maximum glaciations in the Barents Sea: seismic investigations
(Doctoral thesis; Doktorgradsavhandling, 2024-09-19)The main objective of this PhD thesis is to improve understanding of the evolution of pre-Last Glacial Maximum Barents Sea glaciations through the study of glacial deposits from the continental margin using 3D and 2D seismic reflection data. Paper 1 presents a new chronostratigraphic framework, covering the last ∼2.7 Ma, for the Svalbard-Barents Sea margin, using 2D seismic data to extend available ... -
Combinatorics and semi-algebraic geometry of orbit spaces: Hyperbolic and stable polynomials, the degree principle and few inequalities defining orbit spaces
(Doctoral thesis; Doktorgradsavhandling, 2024-09-20)<p>Algebraic geometry studies the set of common zeros of a system of polynomials in one or several variables - most commonly over algebraically closed fields. Real algebraic geometry studies sets defined by a finite system of polynomial inequalities. <p>A starting point for modern real algebraic geometry can be traced back to Hilbert: In 1888, Hilbert showed the existence of nonnegative polynomials ... -
Slicing orbit spaces: Geometry and combinatorics of hyperbolic and even-hyperbolic slices
(Doctoral thesis; Doktorgradsavhandling, 2024-09-18)Motivated by a connection to Timofte’s degree and halfdegree principle we study canonical hyperbolic slices, that is, sets of univariate hyperbolic polynomials that share the same first few coefficients. We study the geometric and combinatorial properties of a natural stratification of these slices and use these properties to improve upon the degree principle. Amongst the geometric properties we ... -
Iceberg Detection for Arctic Operations - A Comparison of C- and L-band Wide-Swath SAR
(Doctoral thesis; Doktorgradsavhandling, 2024-09-13)The accurate detection and mapping of icebergs in the Arctic is important for the safety of maritime traffic and offshore infrastructure and for monitoring the health of marine-terminating glaciers. Synthetic Aperture Radar (SAR) images from satellites have proven to be a useful tool for Arctic monitoring, and C-band SAR images are currently used for operational iceberg monitoring in selected ... -
Exploring fluorination in MBL inhibitor design
(Doctoral thesis; Doktorgradsavhandling, 2024-06-26)<p>Antimicrobial resistance (AMR) achieved through, among others, β-lactamase activity, remains an ongoing challenge for the treatment of infections caused by antibiotic-resistant pathogens. Metallo-β-lactamase (MBL)-expressing bacteria, resistant to most β-lactam antibiotics, are of growing clinical relevance with currently no approved treatment options available. The most common approaches to ... -
Structural characterisation and drug-lipid interaction by NMR spectroscopy
(Doctoral thesis; Doktorgradsavhandling, 2024-06-19)<p>Since the discovery of antimicrobial agents and the extensive use in infection treatment and prevention, antimicrobial resistance (AMR) has become a rapidly increasing problem. The World health organisation (WHO) surveys a wide range of human pathogens, including several multi-resistant pathogens causing infections with high morbidity and mortality. Emphasising the urgency of new treatment ... -
Modelling the Earth System - From Tipping Elements to Reconstructions
(Doctoral thesis; Doktorgradsavhandling, 2024-06-17)Climate change can trigger climate tipping points, which are among the major threats to human society. Tipping points are thresholds beyond which a system undergoes abrupt, often irreversible, changes even if the external forcing is brought to a halt. Several large-scale elements in the Earth system are considered tipping elements with global consequences once critical thresholds are crossed and ... -
Dia-Continua: An Information System for Type 1 Diabetes Consultation. (Interoperability, Privacy, and Information Quality on a FHIR-Based Information System for Type 1 Diabetes Consultations based on Patient-Generated Health Data)
(Doctoral thesis; Doktorgradsavhandling, 2024-05-30)Patient-generated health data (PGHD) is required to monitor chronic conditions like Type 1 Diabetes (T1D). This data includes information from medical devices like insulin pumps and continuous glucose monitors and lifestyle insights from commercial wearables devices such as smartwatches. To improve the quality of medical consultations, we need a unified information system that can integrate ... -
Unleashing the VAMPyR. A Python Journey into the Realm of Multiwavelets and Quantum Chemisty
(Doctoral thesis; Doktorgradsavhandling, 2024-04-04)This thesis presents VAMPyR, an advancement in quantum chemistry that significantly mitigates the challenges inherent in high-precision computational methods. By providing a Python interface to the multiwavelet-based functionalities of MRCPP, VAMPyR enables a more intuitive, accessible, and efficient approach to quantum chemical calculations, reducing the complexity traditionally encountered with ... -
Towards Interpretable, Trustworthy and Reliable AI
(Doctoral thesis; Doktorgradsavhandling, 2024-03-15)<p>The field of artificial intelligence recently witnessed remarkable growth, leading to the development of complex deep learning models that perform exceptionally across various domains. However, these developments bring forth critical issues. Deep learning models are vulnerable to inheriting and potentially exacerbating biases present in their training data. Moreover, the complexity of these models ... -
Exploring the Potential of CO2: Enantioselective C-C Bond Formation
(Doctoral thesis; Doktorgradsavhandling, 2024-03-08)CO<sub>2</sub> is a renewable source of carbon that has not yet been properly utilized. The reason for this is mostly due to its kinetic and thermodynamic stability. The potential renewability of CO<sub>2</sub>, coupled with environmental concerns, has motivated scientists worldwide to develop new artificial carbon cycles for chemical fixation of CO<sub>2</sub>. Unfortunately, the pronounced inertness ... -
Mechanisms of enzyme adaptation to extreme environments: The rational design of a thermophilic chorismate mutase
(Doctoral thesis; Doktorgradsavhandling, 2024-02-26)<p>Extremophiles, especially those living in high-temperature environments, exhibit unique enzymatic mechanisms that allow survival under conditions detrimental to most life forms. Of particular interest is thermophiles, which are able to thrive at temperatures at which psychrophiles and mesophiles unfold and cease to function. The mechanisms by which these enzymes are able to overcome this temperature ... -
Label-free super-resolution optical microscopy
(Doctoral thesis; Doktorgradsavhandling, 2024-02-06)To see structures well below 200 nm using visible light, super-resolution techniques have been developed. Most of these techniques rely on fluorescence labelling or use of artificial materials to go beyond the Abbe limit. Therefore, achieving super-resolution in the label-free regime is the problem that is being addressed in this thesis. In this work, high-index contrast dielectric waveguides are ...
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