Mastergradsoppgaver i teknologi - anvendt fysikk: Recent submissions

Now showing items 41-60 of 70

    • Oil Spill Analysis Using Hybrid-Polarization Synthetic Aperture Radar 

      Høifødt, Audun Leonard (Master thesis; Mastergradsoppgave, 2016-06-01)
      The goal for this thesis is to test various Hybrid-Polarization (HP) Synthetic Aperture Radar (SAR) parameters using actual HP data, and to evaluate the validity of these parameters with respect to oil slick detection. As part of the evaluation, the impact of the system noise and incidence angle on the SAR images is discussed. It is shown that the Signal-to-Noise Ratio (SNR) of the sensor has a ...

    • On the improvement and acceleration of eigenvalue decomposition in spectral methods using GPUs 

      Johansen, Thomas A. Haugland (Master thesis; Mastergradsoppgave, 2016-12-08)
      The key objectives in this thesis are; the study of GPU-accelerated eigenvalue decomposition in an effort to uncover both benefits and pitfalls, and then to investigate and facilitate a future GPU implementation of the symmetric QR algorithm with permutations. With the current trend of having ever larger datasets both in terms of features and observations, we propose that GPU computation can help ...

    • Wind resource assessment using mesoscale modelling. A case study at the potential wind farm site Rieppi 

      Blæsterdalen, Torgeir (Master thesis; Mastergradsoppgave, 2016-06-01)
      The growing wind power industry, increased occurrence of extreme weather, and the need for becoming independent of fossil fuels motivate the research on accurate simulation of near-surface wind. The aim of this study is wind resource assessment at the potential wind park site Rieppi, using two on-site measurement masts, simulations from the Weather Research and Forecasting (WRF) model, and ERA-Interim ...

    • Sensitivity analysis of Gaussian process machine learning for chlorophyll prediction from optical remote sensing 

      Blix, Katalin (Master thesis; Mastergradsoppgave, 2014-05-30)
      The machine learning method, Gaussian Process Regression (GPR), has lately been introduced for chlorophyll content mapping from remotely sensed data. It has been shown that GPR has outperformed other machine learning and empirical methods in accuracy, speed and stability. Moreover, GPR not only estimates the chlorophyll content, it also provides the certainty level of the prediction, allowing the ...

    • Design and experimental investigation of charge amplifiers for ultrasonic transducers 

      Hansen, Svein Kristian Esp (Master thesis; Mastergradsoppgave, 2014-06-02)
      Amplifiers are used in all types of electrical circuits to boost signal and there is a huge variety in designs used for different applications. For ultrasonic applications our group has previously used commercial available transimpedance amplifiers that converts a current to a voltage, but these amplifiers have a linear response over its frequency range. To preserve as much information as ...

    • Optical Trapping, Levitation and Tracking of Microparticles Using Waveguides 

      Helle, Øystein Ivar (Master thesis; Mastergradsoppgave, 2014-06-02)
      Microparticles are trapped by optical forces created by the evanescent field present on the surface of an optical waveguide. An optical waveguide loop with an intentional gap is used to propel and stably hold the trapped particles. The particles are trapped in the gap of the loop by counter-diverging fields. Simulations indicate that particles trapped in the gap on a strip waveguide will be levitated. ...

    • Investigating robot navigation in health care with the Giraff telepresence robot 

      Kåven, Ove Henrik (Master thesis; Mastergradsoppgave, 2013-10-29)
      The Norwegian public healthcare system will not have the manpower to care for the elderly at the same level as now, unless technological solutions are found to make the most of the available manpower. This thesis investigates potential technologies for allowing the Giraff, a telepresence robot, to navigate and patrol an eldercare center autonomously, thus letting caregivers save time when checking ...

    • Particle tracking in 3D 

      Brox, Petter (Master thesis; Mastergradsoppgave, 2013-06)
      The evanescent field of an optical waveguide can be used to trap and propel microscopic particles. A 1µm particle is trapped on a strip waveguide and propelled forward until it reaches a 10µm gap at the centre of a loop, created by splitting the waveguide into two branches. According to simulations, the particle will be elevated 3µm in the gap and be stably trapped in the middle of the gap. The goal ...

    • Comparing SAR measurments of natural oil seeps in the Gulf of Mexico with mineral and biological slicks in the North Sea 

      Hanssen, Claes Anders Storm (Master thesis; Mastergradsoppgave, 2013)
      In this thesis, natural oil seeps in Synthetic Aperture Radar (SAR) images are studied. The intension is to compare seeps to known oil slicks as emulsion-oil, crude-oil and plant-oil. TerraSAR-X and Radarsat-2 data with these di erent slicks are analyzed. Polarimetric features are extracted for all the scenes, histograms and scatterplots of values from the slicks are evaluated. Finally a ...

    • Experimental and numerical estimation of ultrasonic attenuation in polymers based on wave transmission methods 

      Grimstad, Trude (Master thesis; Mastergradsoppgave, 2013-07-01)
      PI-film, also known as Kapton, is a widely used polymer in the production of electronic equipment. Its use in printed circuit boards and sensors is increasing. It is therefore important to have knowledge about ultrasonic attenuation in the polymer. The main goal of this thesis was to investigate the attenuation of ultrasound through different polymers with different thicknesses. The presentation ...

    • Mean shift spectral clustering using kernel entropy component analysis 

      Agersborg, Jørgen Andreas (Master thesis; Mastergradsoppgave, 2012-06-01)
      Clustering is an unsupervised pattern recognition technique for finding natural groups in data, whether it is a grouping of web pages found by a search engine or segmenting satellite images into different types of ground cover. There exists a variety of different ways to perform clustering ranging from heuristics rules designed for a specific dataset to general procedures which can be applied to all ...

    • Information theoretic learning with K nearest neighbors : a new clustering algorithm 

      Vikjord, Vidar Vangen (Master thesis; Mastergradsoppgave, 2012-06-01)
      The machine learning field based on information theory has received a lot of attention in recent years. Through kernel estimation of the probability density functions, methods developed with information theoretic measures are able to use all the statistical information available in the data, not just a finite number of moments. However, by using kernel estimation, the methods are dependent on choosing ...

    • Semi-supervised Classification using Kernel Entropy Component Analysis and the LASSO. 

      Myhre, Jonas Nordhaug (Master thesis; Mastergradsoppgave, 2011-12-15)
      In this thesis we present a new semi-supervised classification technique based on the Kernel Entropy Component Analysis (KECA) transformation and the least absolute shrinkage selection operator (LASSO). The latter is a constrained version of the least squares classifier. Traditional supervised classification techniques only use a limited set of labeled data to train the classifier, thus leaving ...

    • Ultrasound sensor for biomedical applications 

      Øberg, Helge (Master thesis; Mastergradsoppgave, 2011-12-15)
      Vesicoureteral reflux (VUR) is an abnormality that causes urine to flow back from the bladder to the kidneys, which may cause renal scarring and kidney damage. A non-ionizing and non-invasive VUR diagnostic technique, based on microwave hyperthermia, is under development. The possibility for improved hyperthermia efficiency and patient safety through implementation of ultrasound transducers is the ...

    • Improved hardware stability and signal amplification in a medical microwave radiometer 

      Tobiassen, Alexander (Master thesis; Mastergradsoppgave, 2010-10-27)
      Breast cancer is one of the most frequent types of cancer in the female population today. Modern diagnostic modalities, while proven to be helpful within large scale screening programs, are inherently limited with regards to specificity and sensitivity, and use active methods for acquisition of information. A passive and non-invasive method for detection and diagnostic purposes could therefore be a ...

    • Time and temperature control of a camera 

      Kristiansen, Anders (Master thesis; Mastergradsoppgave, 2010-07-13)
      In scientific experiments there are an increasing usage of cameras, along with other instruments, to observe parameters of physical processes. In this thesis, we will discuss how a microcontroller (ATMEL ATmega 324 PA) can be used to control the operation temperature in a camera. It will be discussed why this control of temperature can be useful for the quality of the pictures. Since this thesis is ...

    • Design, implementering og evaluering av et trådløst medisinsk radiometer basert på IEEE 802.15.4-standarden og Zigbee. 

      Johansen, Amund Kronen (Master thesis; Mastergradsoppgave, 2009-06-01)
      Brystkreft er den vanligste kreftformen for kvinner og overlevelsesraten er betydelig høyere ved tidlig deteksjon. De vanligste undersøkelsesmetodene (mammografi, ultralyd, MRI) er basert på aktive metoder som medfører en viss strålingsfare. Et enkelt, ikke-invasivt instrument som baserer seg på passive metoder er derfor motivasjonen for denne masteroppgaven. Oppgaven beskriver en konseptuell ...

    • Optisk resonans i mikrokuler av glass med høy brytningsindeks 

      Husabø, Bjarne Janson (Master thesis; Mastergradsoppgave, 2009-06-15)
      I denne oppgaven har vi sett på effekten av lys som kobles fra en bølgeleder inn i optiske mikrokuler av høyindeksglass. Vi har studert Q-faktorer, og funnet at disse er lavere for kuler omgitt av vann enn tørre kuler, men at forskjellen er mindre enn mellom individuelle kuler. Vi har observert høyere ordens resonanser i kuler med større diameter. Vi har også forsøkt å utnytte resonans til å flytte ...

    • Monostatisk antennearray for UWB radar 

      Andersen, Rolf (Master thesis; Mastergradsoppgave, 2009-06)
      Ultrabredbåndet (ultrawideband - UWB) radar brukt til deteksjon av bryst-kreft viser oppløftende resultater på grunn av dens gode romlige oppløsning og dype penetreringsdybde. Bakgrunnen for å bruke UWB-radar til dette formålet er kontrasten mellom de dielektriske egenskapene til friskt brystvev og en kreftsvulst. Noe som vil føre til relativt mye reflektert energi fra kreftsvulsten. En av utfordringene ...

    • Estimering av dempingskoeffisienter i elastiske materialer ved hjelp av bredbåndet ultralyd 

      Ali, Josoph Abuker (Master thesis; Mastergradsoppgave, 2009-07-01)
      Dette er en eksperimentell oppgave der et bredbåndet ultralydsystem er brukt til å undersøke hvordan dempingen av ultralydbølger i elastiske materialer, avhenger av frekvensen. For å gjøre denne undersøkelsen ble det utviklet en holder i pleksiglass med en ultralydtransduser på hver side. I denne holderen kan prøver av ulike materialer lett festes og undersøkes ved at holderen plasseres i et vannbad. ...