English
norskFakultet for naturvitenskap og teknologi
Bla i:
Underenheter
-
EISCAT [20]
-
Institutt for geovitenskap [1041]
-
Institutt for kjemi [605]
Enhetens samlinger
Nye registreringer
-
Compact representation for memory-efficient storage of images using genetic algorithm-guided key pixel selection
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-11-04)In the past few years, we have observed rapid growth in digital content. Even in the biological domain, the arrival of microscopic and nanoscopic images and videos captured for biological investigations increases the need for space to store them. Hence, storing these data in a storage-efficient manner is a pressing need. In this work, we have introduced a compact image representation technique with ... -
Hyperspectral imaging and deep learning for parasite detection in white fish under industrial conditions
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-11-09)Parasites in fish muscle present a significant problem for the seafood industry in terms of both quality and health and safety, but the low contrast between parasites and fish tissue makes them exceedingly difficult to detect. The traditional method to identify nematodes requires removing fillets from the production line for manual inspection on candling tables. This technique is slow, labor intensive ... -
Optimization of trigonometric polynomials with crystallographic symmetry and spectral bounds for set avoiding graphs
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-11-05)We provide a new approach to the optimization of trigonometric polynomials with crystallographic symmetry. This approach widens the bridge between trigonometric and polynomial optimization. The trigonometric polynomials considered are supported on weight lattices associated to crystallographic root systems and are assumed invariant under the associated reflection group. On one hand the invariance ... -
AI-Based Cropping of Ice Hockey Videos for Different Social Media Representations
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-08-23)Sports multimedia is among the most prominent types of content distributed across social media today, and the retargeting of videos for diverse aspect ratios is essential for a suitable representation on different social media platforms. In this respect, ice hockey is quite challenging due to its agile movement pattern and speed, and because the main reference point (puck) is very small. In this ... -
Validating polyp and instrument segmentation methods in colonoscopy through Medico 2020 and MedAI 2021 Challenges
(Journal article; Tidsskriftartikkel; Peer reviewed, 2025-09-05)Automatic analysis of colonoscopy images has been an active field of research motivated by the importance of early detection of precancerous polyps. However, detecting polyps during the live examination can be challenging due to various factors such as variation of skills and experience among the endoscopists, lack of attentiveness, and fatigue leading to a high polyp miss-rate. Therefore, there is ... -
A Theoretical and Empirical Analysis of 2D and 3D Virtual Environments in Training for Child Interview Skills
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-08-12)This paper presents a detailed study of an AI-driven platform designed for the training of child welfare and law enforcement professionals in conducting investigative interviews with maltreated children. It achieves a subjective simulation of interview situation through the integration of fine-tuned GPT-3 models within the Unity framework. The study recruited participants from a range of backgrounds, ... -
Machine learning based prognostics and statistical optimization of the performance of biogas-biodiesel blends powered engine
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-09-12)In this study, waste biomass-derived biogas was employed as the main fuel while the biodiesel-diesel blend was used as pilot fuel. This paper describes the development of a Decision Tree and Response Surface methodology-based statistical framework for prediction modeling and optimization. The compression ratio, fuel injection time, fuel injection pressure, and biogas flow rate were employed as ... -
Sea ice mass balance during the MOSAiC drift experiment: Results from manual ice and snow thickness gauges
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-07-09)Precise measurements of Arctic sea ice mass balance are necessary to understand the rapidly changing sea ice cover and its representation in climate models. During the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition, we made repeat point measurements of snow and ice thickness on primarily level first- and second-year ice (FYI, SYI) using ablation stakes and ... -
Leveraging explainable artificial intelligence for early prediction of bloodstream infections using historical electronic health records
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-11-14)Bloodstream infections (BSIs) are a severe public health threat due to their rapid progression into critical conditions like sepsis. This study presents a novel eXplainable Artificial Intelligence (XAI) framework to predict BSIs using historical electronic health records (EHRs). Leveraging a dataset from St. Olavs Hospital in Trondheim, Norway, encompassing 35,591 patients, the framework integrates ... -
Enhancing Medical Image Quality Using Fractional Order Denoising Integrated with Transfer Learning
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-08-29)In medical imaging, noise can significantly obscure critical details, complicating diagnosis and treatment. Traditional denoising techniques often struggle to maintain a balance between noise reduction and detail preservation. To address this challenge, we propose an “Efficient Transfer-Learning-Based Fractional Order Image Denoising Approach in Medical Image Analysis (ETLFOD)” method. Our approach ... -
Point-cloud clustering and tracking algorithm for radar interferometry
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-10-22)In data mining, density-based clustering, which entails classifying datapoints according to their distributions in some space, is an essential method to extract information from large datasets. With the advent of software-based radio, ionospheric radars are capable of producing unprecedentedly large datasets of plasma turbulence backscatter observations, and new automatic techniques are needed to ... -
The consequences of tritium mix for simulated ion cyclotron emission spectra from deuterium-tritium plasmas
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-10-16)Measurements of ion cyclotron emission (ICE) are obtained from most large magnetically confined fusion plasma experiments, and may be used in future to quantify properties of the fusion-born alpha-particle population in deuterium-tritium (DT) plasmas in ITER. ICE is driven by spatially localised, strongly non-Maxwellian, minority energetic ion populations which relax collectively under the ... -
Polar mesospheric summer echo (PMSE) multilayer properties during the solar maximum and solar minimum
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-11-11)Polar mesospheric summer echoes (PMSEs) are radar echoes that are measured in the upper atmosphere during the summer months and that can occur in several layers. In this study, we aimed to investigate the relationship between PMSE layers ranging from 80 to 90 km altitude and the solar cycle. We investigated 230 h of observations from the EISCAT very high frequency (VHF) radar located near Tromsø, ... -
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 ... -
Liftable Point-Line Configurations: Defining Equations and Irreducibility of Associated Matroid and Circuit Varieties
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-09-28)We study point-line configurations through the lens of projective geometry and matroid theory. Our focus is on their realization spaces, where we introduce the concepts of liftable and quasi-liftable configurations, exploring cases in which an n-tuple of collinear points can be lifted to a nondegenerate realization of a point-line configuration. We show that forest configurations are liftable ... -
Deriving the Ionospheric Electric Field From the Bulk Motion of Radar Aurora in the E-Region
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-10-28)In the auroral E‐region strong electric fields can create an environment characterized by fast plasma drifts. These fields lead to strong Hall currents which trigger small‐scale plasma instabilities that evolve into turbulence. Radio waves transmitted by radars are scattered off of this turbulence, giving rise to the ‘radar aurora’. However, the Doppler shift from the scattered signal does not ... -
Comments on: Data integration via analysis of subspaces (DIVAS)
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-06-06)We would like to start by saying that this is a very interesting paper that outlines a powerful tool that can be applied in a wide range of areas. In our discussion, we focus on how the novel approach potentially can improve classification results in hard tasks within e.g., medicine and geoscience. In such situations, where it is hard to make precise predictions, it is natural to acquire information ... -
Anticipating climate risk in Norwegian municipalities
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-10-11)Climate change is increasingly being coupled to extreme weather and climate events, with an observed increase in intensity and occurrence of climate-related events. Norway is no exception. Though generally considered quite resilient to climate risk, with favorable conditions for adapting on a national level, studies point to regional and local differences. Applying a mixed methods approach we ... -
Co-located OLCI optical imagery and SAR altimetry from Sentinel-3 for enhanced Arctic spring sea ice surface classification
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-07-10)The Sentinel-3A and Sentinel-3B satellites, launched in February 2016 and April 2018 respectively, build on the legacy of CryoSat-2 by providing high-resolution Ku-band radar altimetry data over the polar regions up to 81° North. The combination of synthetic aperture radar (SAR) mode altimetry (SRAL instrument) from Sentinel-3A and Sentinel-3B, and the Ocean and Land Colour Instrument (OLCI) imaging ... -
Cross-modality sub-image retrieval using contrastive multimodal image representations
(Journal article; Tidsskriftartikkel; Peer reviewed, 2024-08-13)In tissue characterization and cancer diagnostics, multimodal imaging has emerged as a powerful technique. Thanks to computational advances, large datasets can be exploited to discover patterns in pathologies and improve diagnosis. However, this requires efficient and scalable image retrieval methods. Cross-modality image retrieval is particularly challenging, since images of similar (or even the ...
RSS 1.0