Viser treff 281-300 av 1402

    • RELAX: Representation Learning Explainability 

      Wickstrøm, Kristoffer; Trosten, Daniel Johansen; Løkse, Sigurd Eivindson; Boubekki, Ahcene; Mikalsen, Karl Øyvind; Kampffmeyer, Michael; Jenssen, Robert (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-03-11)
      Despite the significant improvements that self-supervised representation learning has led to when learning from unlabeled data, no methods have been developed that explain what influences the learned representation. We address this need through our proposed approach, RELAX, which is the first approach for attribution-based explanations of representations. Our approach can also model the uncertainty ...
    • Preconditioning of Summer Melt Ponds From Winter Sea Ice Surface Temperature 

      Thielke, Linda; Fuchs, Niels; Spreen, Gunnar; Tremblay, Bruno; Birnbaum, Gerit; Huntemann, Marcus; Hutter, Nils; Itkin, Polona; Jutila, Arttu; Webster, Melinda A. (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-02-22)
      Comparing helicopter-borne surface temperature maps in winter and optical orthomosaics in summer from the year-long Multidisciplinary drifting Observatory for the Study of Arctic Climate expedition, we find a strong geometric correlation between warm anomalies in winter and melt pond location the following summer. Warm anomalies are associated with thinner snow and ice, that is, surface depression ...
    • Optimal sizing and placement of Electrical Vehicle charging stations to serve Battery Electric Trucks 

      Isaksen, Ole-André (Master thesis; Mastergradsoppgave, 2023-06-01)
      For Norway to reach the emission limits in the Paris Agreement, a substantial amount of CO2 must be reduced. Road traffic alone accounts for a high percentage of the total emissions during 2021. This thesis will focus on electrifying the transport sector and analyzing charging infrastructure for heavy-duty electric vehicles. New charging infrastructure for heavy-duty Electric Vehicles (EVs) provides ...
    • Smart Senja electrical network expansion modeling 

      Marthinussen, Oskar (Master thesis; Mastergradsoppgave, 2023-05-30)
      The addition of variable renewable energy sources into the electrical energy systems of the world has been increasing in recent years. This form of distributed energy production with high production volatility can introduce massive challenges in operating a lower voltage distribution network. One of these affected networks is on the island of Senja in northern Norway, with an eldering radial electrical ...
    • Probabilistic Wind Power Forecasting with Deep Neural Sequence Models 

      Svenøe, Sofie (Master thesis; Mastergradsoppgave, 2023-05-27)
      As the world strives to fulfill the goal of zero-emission established during the Paris agreement, an increasing amount of wind power is integrated into the liberalized electricity markets. With this escalation comes the need for wind power forecasting (WPF) due to the intermittent nature of wind, and WPF is therefore becoming an important field of study to successfully incorporate wind power to the ...
    • Comparing quality of breast cancer care in the Netherlands and Norway by federated propensity score analytics 

      Hamersma, Dave T.; Schreuder, Kay; Geleijnse, Gijs; Heeg, Erik; Cellamare, Matteo; Lobbes, Marc B. I.; Mureau, Marc A. M.; Koppert, Linetta B.; Skjerven, Helle; Nygård, Jan Franz; Groothuis-Oudshoorn, Catharina G. M.; Siesling, Sabine (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-06-05)
      Purpose - The aim of the study was to benchmark and compare breast cancer care quality indicators (QIs) between Norway and the Netherlands using federated analytics preventing transfer of patient-level data.<p> <p>Methods - Breast cancer patients (2017–2018) were retrieved from the Netherlands Cancer Registry and the Cancer Registry of Norway. Five European Society of Breast Cancer Specialists ...
    • Predicting Regions of Local Recurrence in Glioblastomas Using Voxel-Based Radiomic Features of Multiparametric Postoperative MRI 

      Cepeda, Santiago; Luppino, Luigi Tommaso; Pérez-Núñez, Angel; Solheim, Ole Skeidsvoll; García-García, Sergio; Velasco-Casares, María; Karlberg, Anna Maria; Eikenes, Live; Sarabia, Rosario; Arrese, Ignacio; Zamora, Tomás; Gonzalez, Pedro; Jiménez-Roldán, Luis; Kuttner, Samuel (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-03-22)
      The globally accepted surgical strategy in glioblastomas is removing the enhancing tumor. However, the peritumoral region harbors infiltration areas responsible for future tumor recurrence. This study aimed to evaluate a predictive model that identifies areas of future recurrence using a voxel-based radiomics analysis of magnetic resonance imaging (MRI) data. This multi-institutional study included ...
    • Energy budget diagnosis of changing climate feedback 

      Cael, B. B.; Bloch-Johnson, Jonah; Ceppi, Paulo; Fredriksen, Hege-Beate; Goodwin, Philip; Gregory, Jonathan M.; Smith, Christopher J.; Williams, Richard G. (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-04-21)
      The climate feedback determines how Earth’s climate responds to anthropogenic forcing. It is thought to have been more negative in recent decades due to a sea surface temperature “pattern effect,” whereby warming is concentrated in the western tropical Pacific, where nonlocal radiative feedbacks are very negative. This phenomenon has however primarily been studied within climate models. We diagnose ...
    • Assessing ocean ensemble drift predictions by comparison with observed oil slicks 

      Martins de Aguiar, Victor Cesar; Röhrs, Johannes; Johansson, Malin; Eltoft, Torbjørn (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-05-16)
      Geophysical models are cornerstone pieces in marine forecasting of floating objects and pollution, such as marine surface oil slicks. Trajectory forecasts of oil spills inherit the uncertainties from the underlying geophysical forcing. In this work we compare the forecast capabilities of an ocean ensemble prediction system (EPS) to those from a higher resolution deterministic model on ...
    • Improving satellite-based monitoring of the polar regions: Identification of research and capacity gaps 

      Gabarró, Carolina; Hughes, Nick; Wilkinson, Jeremy; Bertino, Laurent; Bracher, Astrid; Diehl, Thomas; Dierking, Wolfgang Fritz Otto; Gonzalez-Gambau, Veronica; Lavergne, Thomas; Madurell, Theresa; Malnes, Eirik; Wagner, Penelope Mae (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-02-17)
      We present a comprehensive review of the current status of remotely sensed and in situ sea ice, ocean, and land parameters acquired over the Arctic and Antarctic and identify current data gaps through comparison with the portfolio of products provided by Copernicus services. While we include several land parameters, the focus of our review is on the marine sector. The analysis is facilitated by the ...
    • A dataset of direct observations of sea ice drift and waves in ice 

      Rabault, Jean; Müller, Malte; Voermans, Joey; Brazhnikov, Dmitry; Turnbull, Ian; Marchenko, Aleksey; Biuw, Martin; Nose, Takehiko; Waseda, Takuji; Johansson, Malin; Breivik, Øyvind; Sutherland, Graig; Hole, Lars Robert; Johnson, Mark; Jensen, Atle; Gundersen, Olav; Kristoffersen, Yngve; Babanin, Alexander; Tedesco, Paulina Souza; Christensen, Kai Håkon; Kristiansen, Martin; Hope, Gaute; Kodaira, Tsubasa; Martins de Aguiar, Victor Cesar; Taelman, Catherine Cecilia A; Quigley, Cornelius Patrick; Filchuk, Kirill; Mahoney, Andrew R. (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-05-03)
      Variability in sea ice conditions, combined with strong couplings to the atmosphere and the ocean, lead to a broad range of complex sea ice dynamics. More in-situ measurements are needed to better identify the phenomena and mechanisms that govern sea ice growth, drift, and breakup. To this end, we have gathered a dataset of in-situ observations of sea ice drift and waves in ice. A total of 15 ...
    • Gender inequality and self-publication are common among academic editors 

      Liu, Fengyuan; Holme, Petter; Chiesa, Matteo; AlShebli, Bedoor; Rahwan, Talal (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-01-16)
      Scientific editors shape the content of academic journals and set standards for their fields. Yet, the degree to which the gender makeup of editors reflects that of scientists, and the rate at which editors publish in their own journals, are not entirely understood. Here, we use algorithmic tools to infer the gender of 81,000 editors serving more than 1,000 journals and 15 disciplines over five ...
    • Attention-Based Neural Network for Solving the Green Vehicle Routing Problem in Waste Management 

      Breimo, Marit Utheim (Master thesis; Mastergradsoppgave, 2023-06-04)
      The transport sector is a major contributor to the emission of greenhouse gases and air pollution. As urbanization and population growth continue to increase, the demand for transportation services grows, emphasizing the need for sustainable practices. Therefore, incorporating sustainability into the transport sector can effectively reduce its negative impacts on the environment and optimize the ...
    • Utilizing batteries in the Norwegian distribution grid 

      Eidissen, Magnus (Master thesis; Mastergradsoppgave, 2023-06-04)
      Recent research indicates that photovoltaic (PV) induced overvoltage can occur in high PVpenetration low voltage distribution networks, due to reverse power flow from power injected to the grid. Since January 2020, the number of PV installations in Norway has seen a 2.7-fold increase in a rising trend. Simultaneously there have been several reports of grid-overvoltage and PV curtailment in the ...
    • Comparison of numerical wind modelling on hectometric and km scales at Kvitfjell wind power plant 

      Rein, Kristine (Master thesis; Mastergradsoppgave, 2023-06-01)
      Evaluating the performance of numerical weather models (NWMs) is crucial to identify the best choice of model for wind resource assessments. This thesis has investigated how well NWMs with different horizontal resolutions reproduced the wind directions, the wind speeds and the associated power production at a wind power plant located in complex terrain. The evaluated models included NORA3, ...
    • Unsupervised segmentation of submarine recordings 

      Kjøtrød, Tor (Mastergradsoppgave; Master thesis, 2023-06-01)
      The thesis focuses on the unsupervised segmentation of submarine recordings collected by the Norwegian Polar Institute (NPI) using hydrophones. These recordings consists of various mammal species, along with other phenomena like vessel engines, seismic activity, and moving sea ice. With sparse labeling of the data, a supervised learning approach is not feasible, necessitating the application of ...
    • Feasibility analysis of capacity expansion in Skjerka power station based on production simulation in ProdRisk. 

      Ingolfsson Dragset, Eivind (Master thesis; Mastergradsoppgave, 2023-05-31)
      The Norwegian energy system has traditionally had an energy surplus with a large share of hydro power. Due to increasing demand of power from large scale electrification, the power system is estimated to experience hours of national power deficient in 2030 even with moderate increase of consumption. Extensive increase of variable production renewable power from wind and solar in Northern Europe has ...
    • Forecasting Wind Turbine Production Losses due to Icing 

      Andersen, Rikke Bjarnesen (Master thesis; Mastergradsoppgave, 2023-05-31)
      In order for wind energy producers to avoid the extra costs of inaccurate production estimates for the day-ahead energy market, precise forecasts of power production during the next day have to be made. For renewables such as wind energy, power production is particularly difficult to predict as it depends on the fluctuating wind speed. In addition, forecasting the power production in cold climates ...
    • Comparative performance analysis of two high-latitude solar photovoltaic systems 

      Fossland, Frank Martin (Master thesis; Mastergradsoppgave, 2023-05-30)
      The global energy demand and the urgency to limit greenhouse gas emissions require a transition to cleaner energy sources. Solar energy harvesting is a compelling solution because it can harness the sun’s enormous resources. Solar photovoltaic technology is widely adopted worldwide due to being versatile, adaptable, and mature. However, low solar irradiation and harsh weather conditions limit its ...
    • Probing power laws in multifrequency AFM 

      Santos Hernandez, Sergio; Gadelrab, Karim; Olukan, Tuza Adeyemi; Font, Josep; Barcons, Victor; Chiesa, Matteo (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-02-17)
      Quantification of conservative forces in multifrequency atomic force microscopy requires solving the general equations of the theory expressed in terms of the virials of interaction. Power law expressions are commonly utilized when dealing with electrostatic, ferroelectric, magnetic, or long range (van der Waals) forces. Here, we discuss long range forces modeled in terms of power laws (n), where ...