Institutt for fysikk og teknologi: Recent submissions
Now showing items 181-200 of 1352
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On confinement and plasma acceleration from a small ECR plasma source
(Conference object; Konferansebidrag, 2019)<p>Electron Cyclotron Resonance (ECR) is a technique to create high density, low temperature plasmas that do not depend on a cathode, like arc discharges and are therefore easier to maintain and have a longer lifespan. The use of the Electron Cyclotron Resonance (ECR) for electron heating for Magnetic Nozzle (MN) thrusters have recently received increased interest, as they have been shown to provide ... -
Should humans work?
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-02-01)Should humans work? A simple question at a time when the advent of AI, automation and robotics claims a privileged position in the future of work. The question is perplexing and confusing however once we enquire into the meaning of technology and work as such: some claim that human jobs and well-being might be threatened by technological advances while others predict an increase in high skilled ... -
Solar energy for residential electric vehicle charging in Northern Norway – a feasibility study
(Conference object; Konferansebidrag, 2018)This paper presents a study of the potential for using photovoltaic (PV) solar energy systems for residential charging of electric vehicles (EVs) in Northern Norway. The objective is to investigate the load match between PV yield and uncontrolled EV charging, in terms of self-consumption and self-sufficiency. The load profile for EV charging is retrieved from a study by the Norwegian Water Resources ... -
Observation of mesospheric dust and ionospheric conditions during the G-chaser rocket campaign
(Conference object; Konferansebidrag, 2019)SPID, Smoke Particle Impact Detector, is a Faraday cup detector designed to measure nanometer-sized meteoric smoke particles during rocket flights. We report measurements made with SPID during the G-Chaser student rocket campaign 13 January 2019 and describe the design of the SPID instruments. Model calculations of dust trajectories within the detector result in an effective cross section of 0.97 ... -
Integrating incidence-angle compensation in the segmentation of UAVSAR images
(Conference object; Konferansebidrag, 2018)<p>SAR images display a characteristic intensity variation along the range dimension, caused by the fact that the backscattered intensities depend on the incidence angle. In the case of wide-swath images, this intensity variation from near range to far range is significant enough to affect image segmentation performed on absolute intensity values. The effects are an over-segmentation which creates ... -
Arctic Field Summer Schools: training the next generation of Arctic researchers
(Conference object; Konferansebidrag, 2018)<p>The Arctic Field Summer Schools project is funded by the Research Council of Norway (NFR) and Norwegian Centre for International Cooperation in Education (SIU), under the grant agreement number 261786/H30. <p>The project supports research and education collaboration among UiT - The Arctic University of Norway, University of Alaska Fairbanks (UAF), USA and University of Calgary (UC), Canada. <p>Through ... -
Modeling Microwave Scattering From Rough Sea Ice Surfaces
(Conference object; Konferansebidrag, 2017)In this paper, COMSOL Multiphysics® was used to simulate the microwave scattering from the rough sea ice surface. A nonperiodic model and a periodic model were built. The nonperiodic model considers the rough surface of finite length and introduces a tapered incident wave. In this model, the strategy of total and scattered-field decomposition (TSFD) was used to formulate the finite-element method ... -
Label-free imaging on waveguide platform with enhanced resolution and contrast
(Conference object; Konferansebidrag, 2021)Chip-based Evanescent Light Scattering (cELS) utilizes the multiple modes of a high-index contrast optical waveguide for near-field illumination of unlabeled samples, thereby repositioning the highest spatial frequencies of the sample into the far-field. The multiple modes scattering off the sample with different phase differences is engineered to have random spatial distributions within the integration ... -
Faszination Nano-Staubteilchen im Kosmos - Astronomie als Puzzle
(Conference object; Konferansebidrag, 2018) -
Radar studies of ionospheric dust - plasma phenomena
(Conference object; Konferansebidrag, 2018)Dust plasma phenomena occur in the Earth ionosphere in particular in the meteor ablation zone at altitudes ~50-95 km and above where radar meteors form. Radar also detect coherent polar mesospheric radar echoes (PME), i.e. radar echoes that are caused by spatial variations in the plasma refractive index at around 80 to 90 km altitude in the Earth’s mesosphere. During summer, PM(S)E form in the ... -
The Fate of Nanodust near the Sun - Comparison of Sputtering and Sublimation lifetimes during CMEs
(Conference object; Konferansebidrag, 2018)The dust environment in the inner Solar system has not been probed so far, but ESA’s Solar Orbiter (2020) and NASA’s Parker Solar Probe (2018) are about cross the inner solar system. From [1] we expect a layer of trapper Nanodust around the Sun. [2] investigated the interaction of grains with the Solar wind. But what is the dust’s fate when they are struck by a Coronal Mass Ejection (CME). Are they ... -
Sputtering through coronal mass ejections and the fate of nanodust near the Sun
(Conference object; Konferansebidrag, 2018) -
Statistical properties of fluctuation driven flows in the outboard mid-plane SOL of Alcator C-Mod
(Conference object; Konferansebidrag, 2018)The scale length of the radial density profile in scrape-off layer plasmas has been shown to depend on the line-averaged plasma density. While first reported on AlcatorC-Mod, recent work verifies this phenomena in JET and ASDEX Upgrade. In low density plasmas with a sheath-limited SOL, the density profiles present a two-scale structure which allows the separation of the SOL into two distinct regions. ... -
KAIRA Science Results
(Conference object; Konferansebidrag, 2018) -
Land cover changes detection in polarimetric SAR data using algebra, similarity and distance based methods
(Journal article; Tidsskriftartikkel, 2017-09-27)Monitoring and surveillance changes around the world need powerful methods, so detection, visualization, and assessment of significant changes are essential for planning and management. Incorporating polarimetric SAR images due to interactions between electromagnetic waves and target and because of the high spatial resolution almost one meter can be used to study changes in the Earth's surface. Full ... -
Analysis of Deep Convolutional Neural Networks Using Tensor Kernels and Matrix-Based Entropy
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-06-03)The aquaculture industry is expanding to meet the daily requirements of humanity from high-quality seafood. In this regard, intensive aquaculture systems are suggested, resulting in high production but being challenged with immunosuppression and disease invaders. Antibiotics were used for a long time to protect and treat aquatic animals; however, continuous use led to severe food safety issues, ... -
Short-Term Load Forecasting with Missing Data using Dilated Recurrent Attention Networks
(Conference object; Konferansebidrag, 2020)Data without annotation are easy to obtain in the real-world, however, established supervised learning methods are not applicable to analyze them. Several learning approaches have been proposed in recent years to exploit the underlying structure of the data without requiring annotations. Semi-supervised learning aims to improve the predictive performance of these unsupervised approaches, by exploiting ... -
Uptake and Degradation of Bacteriophages by Liver Sinusoidal Endothelial Cells
(Conference object; Konferansebidrag, 2018)<p>Bacteriophages (briefly, “phages”) are viruses which target bacteria, and are non-infectious to eukaryotic cells. It is estimated that more than 30 billion phages cross into the human body from the gut each day1, and eventually need to be cleared from the blood circulation. The liver plays a central role in pathogen clearance, and liver sinusoidal endothelial cells (LSECs), which form the lining ... -
Polarimetric Guided Nonlocal Means Covariance Matrix Estimation for Defoliation Mapping
(Conference object; Konferansebidrag, 2020)In this study we investigate the potential for using synthetic aperture radar (SAR) data to provide high resolution defoliation and regrowth mapping of trees in the tundra-forest ecotone. Using aerial photographs, four areas with live forest and four areas with dead trees were identified. Quad-polarimetric SAR data from RADARSAT-2 was collected from the same area, and the complex multilook polarimetric ... -
Generation of Lidar-Predicted Forest Biomass Maps from Radar Backscatter with Conditional Generative Adversarial Networks
(Conference object; Konferansebidrag, 2020)