Institutt for fysikk og teknologi: Recent submissions

Now showing items 1061-1080 of 1276

    • Simulation of Anti-reflection Coated Carbonaceous Spectrally Selective Absorbers 

      Chen, Zhonghua; Amitap, Jain; Boström, Tobias (Journal article; Tidsskriftartikkel; Peer reviewed, 2014-11-22)

    • 20 years of research on the Alcator C-Mod tokamak 

      Greenwald, Martin; Bader, A; Baek, S; Bakhtiari, M; Barnard, H; Beck, W; Bergerson, W; Bespamyatnov, I; Bonoli, P; Brower, D; Brunner, D; Burke, W; Candy, J; Churchill, M; Cziegler, I; Diallo, A; Dominguez, A; Duval, B; Edlund, E; Ennever, P; Ernst, D; Faust, I; Fiore, C; Fredian, T; Garcia, Odd Erik; Gao, C; Goetz, J; Golfinopoulos, T; Granetz, R; Grulke, O; Hartwig, Z; Horne, S; Howard, N; Hubbard, A; Hughes, J; Hutchinson, I; Irby, J; Izzo, V; Kessel, C; Labombard, B; Lau, C; Li, C; Lin, Y; Lipschultz, B; Loarte, A; Marmar, E; Mazurenko, A; McCracken, G; McDermott, R; Meneghini, O; Mikkelsen, D; Mossessian, D; Mumgaard, R; Myra, J; Nelson-Melby, E; Ochoukov, R; Olynyk, G; Parker, R; Pitcher, S; Podpaly, Y; Porkolab, M; Reinke, M; Rice, J; Rowan, W; Schmidt, A; Scott, S; Shiraiwa, S; Sierchio, J; Smick, N; Snipes, JA; Snyder, P; Sorbom, B; Stillerman, J; Sung, C; Takase, Y; Tang, V; Terry, J; Terry, D; Theiler, C; Tronchin-James, A; Tsujii, N; Vieira, R; Walk, J; Wallace, G; White, A; Whyte, D; Wilson, J; Wolfe, S; Wright, G; Wright, J; Wukitch, S; Zweben, S (Journal article; Tidsskriftartikkel; Peer reviewed, 2014)

    • Velocity scaling for filament motion in scrape-off layer plasmas 

      Kube, Ralph; Garcia, Odd Erik (Journal article; Tidsskriftartikkel; Peer reviewed, 2011)

    • Effect of dynamical friction on interchange motion of plasma filaments 

      Kube, Ralph; Garcia, Odd Erik (Journal article; Tidsskriftartikkel; Peer reviewed, 2012)

    • Convergence of statistical moments of particle density time series in scrape-off layer plasmas 

      Kube, Ralph; Garcia, Odd Erik (Journal article; Tidsskriftartikkel; Peer reviewed, 2015)

    • Blob sizes and velocities in the Alcator C-Mod scrape-off layer 

      Kube, Ralph; Garcia, Odd Erik; LaBombard, Brian; Terry, J.L; Zweben, Stewart (Journal article; Tidsskriftartikkel; Peer reviewed, 2013)
      Gas-puff imaging data is used to investigate the dynamics of blob-like structures in the scrape-off layer of Alcator C-Mod. A blob-tracking algorithm is developed and used to compute blob propagation velocities and cross-field sizes for a series of discharges where the line-averaged particle density View the MathML source is varied. We find that the mean radial blob velocity increases from View the ...

    • Estimation of statistical moments for single point measurements in the Scrape Off Layer 

      Kube, Ralph; Garcia, Odd Erik (Conference object; Konferansebidrag, 2014-03-17)

    • Improving Doppler frequency estimation from Envisat data 

      Kræmer, Thomas; Johnsen, Harald; Brekke, Camilla (Conference object; Konferansebidrag, 2014)

    • An Automatic U-distribution and Markov Random Field Segmentation Algorithm for PolSAR Images 

      Doulgeris, Anthony Paul (Journal article; Tidsskriftartikkel; Peer reviewed, 2015)

    • Long-range memory in internal and forced dynamics of millennium-long climate model simulations 

      Østvand, Lene; Nilsen, Tine; Rypdal, Kristoffer; Divine, Dmitry, V.; Rypdal, Martin wibe (Journal article; Tidsskriftartikkel; Peer reviewed, 2014)
      Northern Hemisphere (NH) temperature records from a palaeoclimate reconstruction and a number of millennium-long climate model experiments are investigated for long-range memory (LRM). The models are two Earth system models and two atmosphere–ocean general circulation models. The periodogram, detrended fluctuation analysis and wavelet variance analysis are applied to examine scaling properties ...

    • Short-term wind power prediction based on Markov chain and numerical weather prediction models: A case study of Fakken wind farm 

      Jacobsen, Morten (Master thesis; Mastergradsoppgave, 2014-06-02)
      Rising energy demands and a growing focus on sustainable development have made electricity production from wind energy an attractive alternative to fossil fuels. However the natural variability of wind makes it challenging to implement wind energy into the electrical grid. Accurate and reliable wind power predictions are seen as a key element for an increased penetration of wind energy. This ...

    • Statistical significance of rising and oscillatory trends in global ocean and land temperature in the past 160 years 

      Østvand, Lene; Rypdal, Kristoffer; Rypdal, Martin (Journal article; Tidsskriftartikkel, 2014-10-30)
      Various interpretations of the notion of a trend in the context of global warming are discussed, contrasting the difference between viewing a trend as the deterministic response to an external forcing and viewing it as a slow variation which can be separated from the background spectral continuum of long-range persistent climate noise. The emphasis in this paper is on the latter notion, and a ...

    • 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 ...

    • Modeling iron abundance anhancements in the slow solar wind. 

      Byhring, Hanne Sigrun; Cranmer, S.R.; Lie-Svendsen, Øystein; Habbal, S. Rifai; Esser, Ruth (Journal article; Tidsskriftartikkel; Peer reviewed, 2011)
      We have studied the behavior of Fe ions in the slow solar wind, using a fluid model extending from the chromosphere to 1 AU. Emphasis is on elemental "pileup" in the corona, i.e., a region where the Fe density increases and has a local maximum. We study the behavior of individual Fe ions relative to each other in the pileup region, where Fe(+10) and Fe(+12) have been used as examples. We find that ...

    • Thermal energy recycling at Elkem Salten Verk 

      Rundhaug, Erik Ro (Master thesis; Mastergradsoppgave, 2014-06-01)
      This thesis elucidates thermal energy transfer at Elkem Salten Verk, and tries to determine the most favorable approach on how to provide indoor heating by thermal energy for a building at the plant site. My goal for this thesis was to create some suggestions, regarding the type of heating systems and their energy rates in order to provide enough heating power for Miljøbygget.

    • "Numerical modeling of microwave interactions with sea ice" 

      Kampffmeyer, Michael Christian (Master thesis; Mastergradsoppgave, 2014-06-02)
      Remote sensing is a key instrument for monitoring sea ice surface properties over large areas. Synthetic Aperture Radar (SAR) as well as Real Aperture Radar (RAR) are two types of radars that are extensively used in this context and measure the backscatter of the surface that they illuminate. Backscattering of waves from rough surfaces is complicated and depends, among other things, on the roughness ...

    • Undersjøiske skred i Balsfjorden, Nord-Norge: egenskaper og sammensetning 

      Iversen, Vera (Master thesis; Mastergradsoppgave, 2014-06-02)
      Batymetridata, høyoppløselige seismisk data samt en sedimentkjerne fra indre Balsfjorden, Troms, nord-Norge, har blitt analysert for å undersøke sedimentasjonsprosesser i løpet av Holocen, med spesiell fokus på undersjøiske rasavsetninger. Hovedvekt av denne oppgaven ligger på analyse av den 8,67 m lange sedimentkjernen JM11-001-PC. Dette inkluderte beskrivelse av sedimentoverflate og røntgen ...

    • Detection of avalanche debris fields in high resolution SAR imagery 

      Vognild, Erlend (Master thesis; Mastergradsoppgave, 2014-06-02)
      During the winter of 2013, Northern Norway saw several large avalanche episodes that caused closed roads and loss of human lives. On Senja and Kval\o ya two large avalanches were reported and images from RADARSAT-2 were ordered in ultrafine mode with the goal of detecting these large avalanches in SAR images. Later that year another two images were ordered from RADARSAT-2 that were be used as reference ...

    • Ocean modeling in Northern Norway: A tidal verification study 

      Djuve, Hans Kristian (Master thesis; Mastergradsoppgave, 2014-06-02)
      The coast of Northern Norway has for the first time been modeled using an unstructured grid. The modeling is done using two separate grids of different resolution, and the model data is compared to measurements done along the coast to verify its performance for both the fine and coarse grid. The model is a 2-D depth integrated model of tidal circulation with bottom friction. The data have been ...