Fakultet for naturvitenskap og teknologi: Recent submissions
Now showing items 2221-2240 of 5379
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Wind Power Prediction with Machine Learning Methods in Complex Terrain Areas
(Master thesis; Mastergradsoppgave, 2021-06-29)The increasing amount of intermittant wind energy sources connected to the power grid present several challenges in balancing the power network. Accurate prediction of wind power production is identified as one of the most important measures for balancing the power network while maintaining a sustainable integration of wind power in the power grid. However, the volatile nature of wind makes wind ... -
Detection and Delineation of Produced Water Slicks in Sentinel-1 Synthetic Aperture Radar Images
(Master thesis; Mastergradsoppgave, 2021-06-21)Near oil and gas platforms oil detection services regularly detect oil slicks that are a result of legal releases of produced water. These slicks are usually observed using SAR imagery and the important task of observing and monitoring these slicks is as of now carried out manually by human operators aggregated with reported release information. In this thesis we propose three separate approaches ... -
Detection of Marine Plastic Debris in the North Pacific Ocean using Optical Satellite Imagery
(Master thesis; Mastergradsoppgave, 2021-06-15)Plastic pollution is ubiquitous across marine environments, yet detection of anthropogenic debris in the global oceans is in its infancy. Here, we exploit high-resolution multispectral satellite imagery over the North Pacific Ocean and information from GPS-tracked floating plastic conglomerates to explore the potential for detecting marine plastic debris via spaceborne remote sensing platforms. ... -
Preliminary Evaluation of a mHealth Coaching Conversational Artificial Intelligence for the Self-Care Management of People with Sickle-Cell Disease
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020)Adherence to the complex set of recommended self-care practices among people with Sickle-Cell Disease (SCD) positively impacts health outcomes. However, few patients possess the required skills (i.e. disease-specific knowledge, adequate levels of self-efficacy). Consequently, adherence rates remain low and only 1% of patients are empowered enough to master the self-care practices. Health coaching ... -
Fluorescence fluctuation-based super-resolution microscopy using multimodal waveguided illumination
(Journal article; Tidsskriftartikkel; Peer reviewed, 2021-07-19)Photonic chip-based total internal reflection fluorescence microscopy (c-TIRFM) is an emerging technology enabling a large TIRF excitation area decoupled from the detection objective. Additionally, due to the inherent multimodal nature of wide waveguides, it is a convenient platform for introducing temporal fluctuations in the illumination pattern. The fluorescence fluctuation-based nanoscopy technique ... -
The geochemical signature of Cu mineralisation preserved in stream sediments from the Alta-Kvænangen Tectonic Window, Northern Norway
(Master thesis; Mastergradsoppgave, 2021-06-13)The Paleoproterozoic Greenstone Belts of Fennoscandia are metamorphosed and deformed volcanic and sedimentary basins with a high metallic ore potential. One of those, the Alta-Kvænangen Tectonic Window (AKTW), is exposed as a window below the Caledonides of Northern Norway. The Kåfjord area located within the AKTW hosts numerous known Cu occurrences. The Cu mineralisation in Kåfjord occurs mostly ... -
Imputation and classification of time series with missing data using machine learning
(Mastergradsoppgave; Master thesis, 2021-06-21)This work is about classifying time series with missing data with the help of imputation and selected machine learning algorithms and methods. The author has used imputation to replace missing values in two data sets, one containing surgical site infection (SSI) data of 11 types of blood samples of patients over 20 days, and another data set called uwave which contain 3D accelerometer data of several ... -
Complexity-Entropy Analysis of Chaotic and Intermittent Fluctuations in Physical Systems
(Master thesis; Mastergradsoppgave, 2021-06-01)Time series from chaotic and stochastic systems share properties which can make it hard to distinguish them from each other. The Complexity-Entropy analysis provides appropriate measures of entropy and complexity and representing the calculated values in the representation space, the Complexity-Entropy plane, have been shown to be able to distinguish between time series of stochastic and chaotic ... -
Probabilistic Load Forecasting with Deep Conformalized Quantile Regression
(Master thesis; Mastergradsoppgave, 2021-06-01)The establishment of smart grids and the introduction of distributed generation posed new challenges in energy analytics that can be tackled with machine learning algorithms. The latter, are able to handle a combination of weather and consumption data, grid measurements, and their historical records to compute inference and make predictions. An accurate energy load forecasting is essential to assure ... -
Investigating the Impact of Susceptibility Artifacts on Adjacent Tumors in PET/MRI through Simulated Tomography Experiments
(Mastergradsoppgave; Master thesis, 2021-06-01)For quantitative PET imaging, attenuation correction (AC) is mandatory. Currently, all main vendors of hybrid PET/MRI systems apply a segmentation-based approach to compute a Dixon AC-map based on fat and water images derived from in- and opposed-phase MR-images. Changes in magnetic susceptibility pose major problems for MRI, which may lead to artifacts resulting in tissue misclassification in the ... -
Extracting Information from Multimodal Remote Sensing Data for Sea Ice Characterization
(Mastergradsoppgave; Master thesis, 2021-06-01)Remote sensing is the discipline that studies acquisition, preparation and analysis of spectral, spatial and temporal properties of objects without direct touch or contact. It is a field of great importance to understanding the climate system and its changes, as well as for conducting operations in the Arctic. A current challenge however is that most sensory equipment can only capture one or fewer ... -
Geochemical characteristics of sediment- and mafic rock-hosted Cu deposits in the Kåfjord area, Alta-Kvænangen Tectonic Window, Northern Norway
(Mastergradsoppgave; Master thesis, 2021-06-15)The Precambrian Alta-Kvænangen Tectonic Window (AKTW) located in the northern part of Norway, hosts different types of copper mineralization. Some of Cu occurrences have been previously mined, but their geochemical and stable isotope characteristics have not been a subject of detailed investigations, and therefore the relevant ore-forming processes are still poorly understood. This study, brings new ... -
Cross-platform application of a sea ice classification method considering incident angle dependency of backscatter intensity and its use in separating level and deformed ice
(Journal article; Tidsskriftartikkel; Peer reviewed, 2021)Wide-swath C-band synthetic aperture radar (SAR) has been used for sea ice classification and estimates of sea ice drift and deformation since it first became widely available in the 1990s. Here, we examine the potential to distinguish surface features created by sea ice deformation using ice type classification of SAR data. To perform this task with extended spatial and temporal coverage, we ... -
Newly-formed sea ice distinction near the oil platform Prirazlomnaya in the Pechora Sea using polarimetric Radarsat-2 SAR observations
(Journal article; Tidsskriftartikkel; Peer reviewed, 2021-04-01)A polarimetric approach developed to discriminate oil slicks and look-alikes was used to study the polarimetric properties of newly-formed ice (NFI) observed near the Prirazlomnaya oil platform. This approach is based on the multipolarization parameter called Resonant to Non-resonant signal Damping (RND), which is related to the ratio between the ice damping and the short wind waves and wave breakings. ... -
Resilience Assessment of Wind Farms in the Arctic with the Application of Bayesian Networks
(Journal article; Tidsskriftartikkel; Peer reviewed, 2021-07-22)Infrastructure systems, such as wind farms, are prone to various human-induced and natural disruptions such as extreme weather conditions. There is growing concern among decision makers about the ability of wind farms to withstand and regain their performance when facing disruptions, in terms of resilience-enhanced strategies. This paper proposes a probabilistic model to calculate the resilience of ... -
Modeling and simulation of power and energy demands to dimension an alternative energy supply for the aquaculture industry. Use of OpenModelica to develop an applicable simulation model for the energy and power demands
(Master thesis; Mastergradsoppgave, 2020-07-11)The purpose of the research is to investigate whether feed barges currently running on diesel generator can be powered by alternative energy sources where power from shore is limited. Through data collection, several models are developed in OpenModelica to represent the power and energy distribution on a feed barge. Using the Power Systems library provided in OpenModelica, it has offered benefits ... -
Multi-mission remote sensing of low concentration produced water slicks
(Journal article; Tidsskriftartikkel, 2021-04)Produced water is legally released from oil platforms and often detected by oil spill detection services despite their low oil concentrations. Using fully-polarimetric RADARSAT-2 and dual-polarimetric Sentinel-1 data we investigate their synthetic aperture radar (SAR) characteristics. Detectability ranges within the SAR and optical Sentinel-2 and PlanetScope images are assessed and compared to in-situ ... -
The Mjølnir Impact Crater in the central Barents Sea - a potential hydrocarbon system?
(Master thesis; Mastergradsoppgave, 2020-05-15)A meteor impact event on the Bjameland Platform in the Norwegian Barents Sea about 142 ± 2.6 million years ago formed the Mjølnir Impact Crater. The structure has diameter of 40 km impacting the Mesozoic stratigraphy, and has previously been investigated with emphasis on the dynamics of the impact, the structure formation, sedimentation and post-impact tectonics. Impact structures have proven to be ... -
Improving Chlorophyll-a Estimation from Sentinel-2 (MSI) in the Barents Sea using Machine Learning
(Journal article; Tidsskriftartikkel; Peer reviewed, 2021-04-22)This article addresses methodologies for remote sensing of ocean Chlorophyll-a (Chl-a), with emphasis on the Barents Sea. We aim at improving the monitoring capacity by integrating in situ Chl-a observations and optical remote sensing to locally train machine learning (ML) models. For this purpose, in situ measurements of Chl-a ranging from 0.014–10.81 mg/m <sup>3</sup> , collected for the years ... -
The pure PV-EV energy system – A conceptual study of a nationwide energy system based solely on photovoltaics and electric vehicles
(Journal article; Tidsskriftartikkel; Peer reviewed, 2021-03-08)The objective of this conceptual study is to reveal the substantial potential and synergy of solar energy and electric vehicles (EVs) working together. This potential is demonstrated by studying the feasibility of a nationwide energy system solely reliant on solar energy and EVs. Photovoltaic (PV) solar energy is already an important energy source globally, but due to its intermittency it requires ...