Viser treff 21-40 av 74

    • Time Series Forecasting with Recurrent Neural Networks in Presence of Missing Data 

      Choi, Changkyu (Master thesis; Mastergradsoppgave, 2018-11-24)
      In many applications, time series forecasting plays an irreplaceable role in time-varying systems such as energy markets, financial markets, and so on. Predicting the dynamic of time-varying systems is essential but is a difficult task because it depends on not only the nature of the system but also on external influences, such as environmental conditions and social and economic status. Recurrent ...
    • Investigation of Thermo-Optical Phase Modulator for Chip Based Structured Illumination Microscopy 

      Das, Sourov Kumar (Master thesis; Mastergradsoppgave, 2018-11-21)
      Optical nanoscopy is an emerging field and enables super-resolution of biological cells. Among the existing nanoscopy techniques, structured illumination microscopy (SIM) is most promising candidate for live cell imaging due to its high-imaging speed, limited photo-toxicity and its suitability with most commonly used fluorophore. One of research focus of the optics group at the department is to ...
    • Kara-Siberian sea ice anomaly and its impact on the atmosphere 

      Balafkan, Nozhan (Master thesis; Mastergradsoppgave, 2018-05-15)
      The behavior of the autumn and winter weather pattern over Europe and Eurasia was investigated during two periods of high and low ice concentration in September over the Kara-Siberian sea. A statistically significant anomalous energy flux from the east Siberian sea to the atmosphere was detected during October of low ice years. Furthermore, an anomalous behavior in the atmospheric circulation was ...
    • Angle Dependent Reflectance and Performance of Solar Cells and Absorbers 

      Jordheim, Øystein (Master thesis; Mastergradsoppgave, 2018-05-14)
      In this thesis, the reflectance was measured for angles from 10 deg to 80 deg for different n-type silicon based solar cells and for solar absorbers. The measurements were done with unpolarized, p polarized and s polarized light. The reflectance results show that both the solar cells and solar absorbers perform well under small variation from perpendicular angle well but as the angle of incidence ...
    • Uncertainty Modeling and Interpretability in Convolutional Neural Networks for Polyp Segmentation. 

      Wickstrøm, Kristoffer Knutsen (Master thesis; Mastergradsoppgave, 2018-05-14)
      Colorectal cancer is one of the leading causes of cancer-related deaths worldwide, with prevention commonly done through regular colonoscopy screenings. During a colonoscopy, physicians manually inspect the colon of a patient using a camera in search for polyps, which are known to be possible precursors to colorectal cancer. Seeing that a colonoscopy is a manual procedure, it can be susceptible to ...
    • Temperature and thermal emission of cosmic dust around the Sun, Vega and Fomalhaut 

      Myrvang, Margaretha (Master thesis; Mastergradsoppgave, 2018-05-14)
      Many stars are known to have dust disks, which are created through collisions between planetesimals, comparable to comets and asteroids in our solar system. Cosmic dust around a star absorbs electromagnetic radiation and re-radiates at a longer wavelength, determined by its temperature. The thermal emission of the dust can be observed. In certain systems, including the solar system, some of the dust ...
    • Baneberegninger for støv rundt Sola, Vega og Fomalhaut 

      Stamm, Johann Immanuel (Master thesis; Mastergradsoppgave, 2018-05-14)
      Observasjoner av Vega og Fomalhaut tyder på at de har støvbelter rundt seg. Avstanden fra stjerna er rundt 0,2 astronomiske enheter (AE) og størrelsen til støvpartiklene varierer fra noen nanometer til noen mikrometer. Slikt støv fins også i solsystemet. Denne oppgaven handler om å beregne banen til slike støvpartikler etter danning. Det antas at støvet påvirkes av tre krefter: gravitasjon, ...
    • Optical nanoscopy of tissue sections 

      Villegas Hernandez, Luis Enrique (Master thesis; Mastergradsoppgave, 2018-05-28)
      The study of organ tissues, namely, histology, is essential for clinical medicine, as it allows the identification of a wide range of diseases. Traditionally, two major techniques, optical and electron microscopy, have been used for morphological observation of tissue sections. Optical microscopy (OM) allows for fast-acquisition high-throughput imaging, at the expense of diffraction-limited resolution ...
    • Measuring Wind Using the Internal Stabilisation System of a Quadrotor Drone 

      Simma, Magdalena (Master thesis; Mastergradsoppgave, 2018-05-15)
      This thesis proposes a method of measuring wind using the data logged by the autopilot of a quadrotor drone. The approach is fundamentally different from other attempts found in the literature. Theoretical equations from works on quadrotor control are utilised and supplemented to form the theoretical framework. Static thrust tests provide the necessary parameters for calculating wind estimates. ...
    • Filament motions in magnetized plasmas 

      Enikeev, Mikhail (Master thesis; Mastergradsoppgave, 2018-02-08)
      Interchange motions of magnetized plasmas due to either a non-uniform magnetic field or a gravitational field lead to charge polarization within a filamentary structure and set up convection. In this project we have provided a clear derivation of the two-field model equations that describe these filament motions. We have also derived an energy theorem for small amplitude oscillations. We have ...
    • Spectral measurement improvement through optical tree delineation 

      Toennis, Jonas (Master thesis; Mastergradsoppgave, 2017-11-15)
      Optical tree delineation algorithms have previously been used for satellite data. In this thesis, they are adapted for use from an Unmanned Aerial Vehicle (UAV). An evaluation of three algorithms (Valley Following, Region Growing and Marker Controlled Watershed) as well as different pre-filtering was done to find the best algorithm and filter combination for a species independent delineation. The ...
    • A comparison between optical and SAR classification results for thin sea ice in Storfjorden 

      Quigley, Cornelius (Master thesis; Mastergradsoppgave, 2017-05-31)
      According to the scientific consensus, the Arctic is currently in a state of unprecedented change. In recent years, climate change has been identified as the main cause of Arctic sea ice decline. For this reason, the need to have access to timely and cost effective data is of great importance. Remote sensing via Earth orbiting satellites offers extensive data coverage in areas that are typically ...
    • Modeling Ice-shelf Ocean Interaction at Petermann Glacier, Greenland 

      Bao, Weiyang (Master thesis; Mastergradsoppgave, 2017-05-15)
      Petermann Glacier drains about 4% of the Greenland ice sheet area, with at least 80% of its mass loss through basal melting of the floating ice shelf. Utilizing a high-resolution coupled ice-shelf-ocean model, we aim at understanding the ocean circulation in Nares Strait and the mechanism of oceanic heat supply below the ice shelf as well as quantifying the basal mass loss. The numerical model is ...
    • Optimization of a polymer layer highly doped with Cryptophane-A for methane sensing 

      Yadav, Mukesh (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 

      Singh, Rajwinder (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 ...
    • Laser diagnostics of the mesospheric magnetic field. Understanding remote laser magnetometry in northern Norway 

      Serrano, Alessandra (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 

      Stock, Will (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 ...
    • The volume distribution of artificial aurora induced by HF radio waves in the ionosphere 

      Kvammen, Andreas (Master thesis; Mastergradsoppgave, 2016-08-15)
      This thesis presents three-dimensional modelling of artificial aurora in the ionospheric F layer, induced by high frequency (HF) O-mode radio waves from the EISCAT heating facility. Understanding how HF radio waves produces enhanced emission in the ionosphere has been one of the one of the major motivations for conducting heating experiments during the last decades. A key element for understanding ...
    • System upgrade and data evaluation of the AIRIS riometer 

      Larsen, Ida Marie (Master thesis; Mastergradsoppgave, 2016-06-06)
      The focus of this thesis has been to investigate how to improve the AIRIS data. This has been done by first of all giving the riometer system an overhaul, checking the wiring and receivers as well as upgrading the riometer computer harddisk. As there has been a lot of issues occurring along the way, the focus finally went to pinpointing exactly what is causing the data quality to be poor and coming ...
    • The impact of Arctic late summer sea ice variability on mid-latitude autumn and winter weather. 

      Stoll, Patrick (Master thesis; Mastergradsoppgave, 2015-11-18)
      The influence of Arctic summer sea ice area on autumn and winter climate in the extra-tropic Northern hemisphere is investigated. During the last decades, the Arctic has warmed more than twice the global average rate, a phenomenon called the Arctic Amplification (AA). AA involves a remarkable decrease of the Arctic sea ice cover and a decrease of the latitudinal temperature gradient. Both are supposed ...