Institutt for fysikk og teknologi: Recent submissions
Now showing items 1061-1080 of 1407
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Optimization of a polymer layer highly doped with Cryptophane-A for methane sensing
(Master thesis; Mastergradsoppgave, 2017-05-15)The main objective of this thesis is to optimize the thickness of sensitive polymer layer highly doped with Cryptophane-A for methane pre-concentration and to make the existing sensor more stable and selective towards methane. In recent years, methane detection has become a hot topic due to the strong impact of methane on the global warming and the climate change. There has also been rising ... -
Investigation of inflammatory response of macrophages and trophoblasts using structured illumination microscopy
(Master thesis; Mastergradsoppgave, 2017-05-15)Approximately 800 women die from pregnancy or childbirth-related pregnancy complications around the world every day. One of the major reasons for these complications is inflammation following infection. Approximately 40% cases of preterm births occur due to microbial invasion in the genitourinary track. During inflammation, macrophages present at the feto-maternal junction release an increased amount ... -
Eigen-analysis reveals components supporting super-resolution imaging of blinking fluorophores
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-06-30)This paper presents eigen-analysis of image stack of blinking fluorophores to identify the components that enable super-resolved imaging of blinking fluorophores. Eigen-analysis reveals that the contributions of spatial distribution of fluorophores and their temporal photon emission characteristics can be completely separated. While cross-emitter cross-pixel information of spatial distribution ... -
Laser diagnostics of the mesospheric magnetic field. Understanding remote laser magnetometry in northern Norway
(Master thesis; Mastergradsoppgave, 2017-05-15)This thesis outlines initial motivations and propositions for the Mesospheric Optical Magnetometry (MOM) project, using lidar equipment at ALOMAR observatory in northern Norway to initiate a novel technique for measuring Earth’s magnetic field at approximately 90 km altitude. Included is an in-depth discussion of the physical phenomena within Earth’s mesospheric sodium layer, relevant atomic physics, ... -
Estimation of Neutral Densities in the Thermosphere
(Master thesis; Mastergradsoppgave, 2017-05-17)Ionospheric energy balance is studied with incoherent scatter radar measurements that allow the estimation of neutral density and temperature from a statistical inversion problem. This method has been successfully studied at low latitudes using data over several years to make a robust model. This has not been done within the high latitude auroral regions and there are many factors that can complicate ... -
An initial assessment of the possibilities of fish catch prediction using Gaussian processes
(Master thesis; Mastergradsoppgave, 2016-12-15)The fishing and aquaculture industry is one of the largest industries of Norway. Enhanced knowledge of the distribution of fish in the ocean is important for an economical and sustainable fishing industry. This study investigates the possibilities of using Gaussian processes for regression within fish catch prediction. A dataset that combines catch reports from the Norwegian shipping company Havfisk ... -
Signature of Arctic first-year ice melt pond fraction in X-band SAR imagery
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-03-23)In this paper we investigate the potential of melt pond fraction retrieval from X-band polarimetric synthetic aperture radar (SAR) on drifting first-year sea ice. Melt pond fractions retrieved from a helicopter-borne camera system were compared to polarimetric features extracted from four dual-polarimetric X-band SAR scenes, revealing significant relationships. The correlations were strongly dependent ... -
X-, C-, and L-band SAR signatures of newly formed sea ice in Arctic leads during winter and spring
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-11-02)We examine an extensive synthetic aperture radar (SAR) data set from the Arctic Ocean spanning a time period from January to June 2015, with the aim of identifying multi-polarization parameters that can be used to accurately separate newly formed sea ice from the surroundings. Newly formed sea ice areas both provide favourable routing for ship traffic, and are key to Arctic climate science because ... -
Silicon nitride waveguide platform for fluorescence microscopy of living cells
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017)Waveguide chip-based microscopy reduces the complexity of total internal reflection fluorescence (TIRF) microscopy, and adds features like large field of view illumination, decoupling of illumination and collection path and easy multimodal imaging. However, for the technique to become widespread there is a need of low-loss and affordable waveguides made of high-refractive index material. Here, ... -
Solar Wind from Coronal Funnels and Transition Region Lyalpha
(Journal article; Tidsskriftartikkel; Peer reviewed, 2005-08-10)Using a newly developed gyrotropic solar wind model that extends continuously from the mid-chromosphere to 1 AU and that accounts for radiative losses in the transition region, we have studied the difference between the fast solar wind emanating from a funnel geometry and a ``traditional'' rapidly expanding wind. The main aim is to determine whether or not observations of the Lyalpha intensity in ... -
Assessment of RISAT-1 and Radarsat-2 for Sea Ice Observation from Hybrid-Polarity Perspective
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-10-25)Utilizing several Synthetic Aperture Radar (SAR) missions will provide a data set with higher temporal resolution. It is of great importance to understand the difference between various available sensors and polarization modes and to consider how to homogenize the data sets for a following combined analysis. In this study, a uniform and consistent analysis across different SAR missions is carried ... -
Marine radar properties, analysis and applications
(Master thesis; Mastergradsoppgave, 2017-08-01)In this thesis marine radars are compared with synthetic aperture radars (SAR) and the possibility of cross-over applications are investigated. A first cross-over has been demonstrated by using the TS-CFAR on marine radar images. The TS-CFAR was originally developed for SAR and is a constant false alarm rate (CFAR) detection algorithm based on truncated statistics. Detecting weak targets embedded ... -
Case study of a large-scale solar, wind and hydro power hybrid system in Skibotndalen, Troms
(Master thesis; Mastergradsoppgave, 2017-06-06)The power company Troms Kraft is interested in the feasibility of a large-scale hybrid system in Skibotndalen in Troms. There are two existing hydro power stations in the area, and this thesis concerns the addition of an electric solar power plant of 20 MW and a wind power plant of 21 MW to these stations. As measured solar radiation is not available for one whole year at the location, solarradiation ... -
3-D seismic interpretation of the Samson Dome in the framework of the tectonostratigraphic and fluid migration development of the Western Barents Sea
(Master thesis; Mastergradsoppgave, 2017-06-21)Three-dimensional (3-D) seismic interpretations of data from the Samson Dome show direct connection between the local geological evolution of the area and the regional tectonic and stratigraphic development of the western Barents Sea. Rifting events, halokinetic movements, uplift and glacial processes influenced the area of the Samson Dome. The Samson Dome structure, located in the south-western ... -
The link between fluid flow and glacial erosion along the Ringvassøy- Loppa fault complex, Tromsøflaket, SW Barents Sea
(Master thesis; Mastergradsoppgave, 2017-06-06)This master thesis has focused its efforts to investigate the link between glacial erosion and focused fluid flow in the SW Barents Sea, on the shallow bank area of Tromsøflaket where the Ringvassøy-Loppa Fault Complex borders the Tromsø basin in west, and the Loppa High in east. Here, large, elongated depressions are identified on the buried Upper Regional Unconformity (URU) and may resemble tunnel ... -
Case study of a large-scale solar and wind power hybrid system at Fakken Wind Farm, Troms
(Master thesis; Mastergradsoppgave, 2017-06-01)The objective of this thesis is to investigate the feasibility of a large scale hybrid system at Fakken, Troms. There is already an existing 54 MW wind farm at site. The wind farm has considerably higher power production during winter compared to summer, and the electricity grid is therefore not fully exploited during summer. Adding a solar panel utility to the site could be a solution to this issue. ... -
Changes in paleoceanography and methane release in relation to past climatic variability at Vestnesa Ridge, Svalbard
(Master thesis; Mastergradsoppgave, 2017-06-01)Sediment core HH16-549GC from Vestnesa Ridge in the Fram Strait, western Svalbard, has been investigated in order to reconstruct paleoceanographic and paleoclimatic conditions from 31,000 to 7500 cal years BP. Vestnesa Ridge is located in an area with extensive seepage of methane from the ocean floor. The core is retrieved from within a pockmark to reconstruct possible changes in seepage of methane ... -
Optimization of wind turbine location in urban environment
(Master thesis; Mastergradsoppgave, 2017-06-01)Making energy clean, reliable and readily available is essential for fighting climate change and to supply an ever-rising global power demand. The aim of the study is to identify optimal locations for a wind turbine to be joined to a small-scale hybrid system at the main campus of UiT – The Arctic University of Norway. To identify feasible areas for maximizing electric power production, techniques ... -
Modelling the future of the arctic sea ice cover
(Master thesis; Mastergradsoppgave, 2017-06-01)Record lows in sea ice cover have recently sparked new interest in the small ice cap instability. The change in albedo when sea ice becomes open water introduces a nonlinearity called the ice-albedo feedback. Forcing a joint energy- balance and sea ice model can lead to unstable ice caps in certain parameter regimes. When the ice caps are unstable, a small perturbation will initiate a tipping point ... -
Detailed mapping of faults and fractures along Vestnesa ridge
(Master thesis; Mastergradsoppgave, 2017-05-31)This master thesis is focused on studying the Vestnesa Ridge located west of Svalbard. The Vestnesa Ridge is a 100 km long and about 3 km wide sediment drift located on the recently uplifted Svalbard margin. The crest of the ridge is represented with numerous pockmarks with different size, orientation and elongation. High resolution seismic data connected pockmarks with acoustic chimneys and faults ...