Nye registreringer

  • Ionospheric bow waves and perturbations induced by the 21 August 2017 solar eclipse 

    Zhang, Shun-Rong; Erickson, Philip j.; Goncharenko, Larisa; Coster, Anthea; Rideout, William; Vierinen, Juha (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-12-04)
    During solar eclipses, the Moon's shadow causes a large reduction in atmospheric energy input, including not only the stratosphere but also the thermosphere and ionosphere. The eclipse shadow has a supersonic motion which ...
  • Training Echo State Networks with Regularization Through Dimensionality Reduction 

    Løkse, Sigurd; Bianchi, Filippo Maria; Jenssen, Robert (Journal article; Tidsskriftartikkel; Peer reviewed, 2017)
    In this paper, we introduce a new framework to train a class of recurrent neural network, called Echo State Network, to predict real valued time-series and to provide a visualization of the modeled system dynamics. The ...
  • Estimates of the size distribution of meteoric smoke particles from rocket-borne impact probes 

    Antonsen, Tarjei; Havnes, Ove; Mann, Ingrid (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-11-26)
    Ice particles populating noctilucent clouds and being responsible for polar mesosphericsummer echoes exist around the mesopause in the altitude range from 80 to 90 km during polar summer.The particles are observed when ...
  • Inflammatory response of macrophages and trophoblasts investigated using structured illumination microscopy and quantitative phase microscopy 

    Singh, Rajwinder; Wolfson, Deanna Lynn; Dubey, Vishesh; Ahmad, Azeem; Acharya, Ganesh; Mehta, Dalip Singh; Basnet, Purusotam; Ahluwalia, Balpreet Singh (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-09)
    <i>Introduction</i>: The super-resolution capability of structured illumination microscopy (SIM) (100 nm) enables 3D imaging of mitochondria, and label-free quantitative phase microscopy (QPM) provides nanoscale quantitative ...
  • Radar observations of thermal plasma oscillations in the ionosphere 

    Vierinen, Juha; Gustavsson, Björn Johan; Hysell, David; Sulzer, M.; Perillat, Phil; Kudeki, Erhan (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-06-02)
    Incoherent scatter radar observations of ionospheric plasmas rely on echoes from electron density fluctuations with properties governed by the dispersion relations for ion acoustic and Langmuir waves. Radar observations ...
  • Localized mesosphere-stratosphere-troposphere radar echoes from the E region at 69 degrees N: Properties and physical mechanisms 

    Rapp, Markus; Leitert, Lasse; Latteck, Ralph; Zecha, Marius; Hoffmann, Peter; Höffner, Josef; Hoppe, Ulf-Peter; La Hoz, Cesar; Thrane, Eivind (Journal article; Tidsskriftartikkel; Peer reviewed, 2011-02-25)
    We present the first observations, to our knowledge, of a new class of high‐latitude mesosphere‐stratosphere‐troposphere radar echoes from the E region as observed with the Arctic Lidar Observatory for Middle Atmosphere ...
  • Agreement and Complementarity of Sea Ice Drift Products 

    Johansson, Malin; Berg, Anders (Journal article; Tidsskriftartikkel; Peer reviewed, 2016-01-08)
    Changes in Arctic sea ice have raised questions about changes in sea ice drift patterns. Reduced sea ice coverage may open up the Arctic to further exploration of maritime activities, particularly during the summer months. ...
  • Estimation of atmospheric temperature and humidity profiles from MODIS data and radiosond data using artificial neural network 

    Akbari, Vahid; Amini, Jalal; Saradjian, Mohammad Reza; Motagh, Mahdi (Journal article; Tidsskriftartikkel; Peer reviewed, 2008)
    The aim of this study is to test the quality of the neural network for retrieving the temperature and humidity by comparison with the radiosond values and a linear regression method. Remote sensed images give useful ...
  • Chirp coded ultrasonic pulses used for scanning acoustic microscopy 

    Habib, Anowarul; Melandsø, Frank (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-11-02)
    In the present study, chirp coded pulses are investigated with respect to high frequency imaging. These pulses were used drive broadband polymer transducers assembled from an adhesive-free layer-be-layer deposition method. ...
  • 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 ...
  • Combination of large and small basis sets in electronic structure calculations on large systems 

    Røeggen, Inge Arvid; Gao, Bin (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-04)
    Two basis sets-a large and a small one-are associated with each nucleus of the system. Each atom has its own separate one-electron basis comprising the large basis set of the atom in question and the small basis sets for ...
  • Subaperture analysis of polarimetric SAR data for iceberg detection 

    Akbari, Vahid; Doulgeris, Anthony Paul; Brekke, Camilla (Peer reviewed; Konferansebidrag; Book, 2016-11-03)
    This paper is focused on investigations of the improved detection of icebergs in open water using spectral analysis of polarimetric SAR data. The objectives of this study are to analyze the behavior of ice objects in open ...
  • Cross-Correlation Between Polarization Channels in SAR Imagery Over Oceanographic Features 

    Brekke, Camilla; Jones, Cathleen; Skrunes, Stine; Holt, Benjamin; Espeseth, Martine; Eltoft, Torbjørn (Journal article; Tidsskriftartikkel; Peer reviewed, 2016-05-11)
    This letter discusses cross-correlation features de- rived from near-coincident RADARSAT-2 quad-polarimetric and RISAT-1 hybrid-polarity (HP) measurements collected during the NOrwegian Radar oil Spill Experiment in ...
  • Is a net life cycle balance for energy and materials achievable for a zero emission single-family building in Norway? 

    Kristjansdottir, Torhildur Fjola; Houlihan Wiberg, Aoife Anne Marie; Andresen, Inger; Georges, Laurent; Heeren, Niko; Good, Clara; Brattebø, Helge (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-03-01)
    In this study, the objective is to redesign a previous concept for a single-family Zero greenhouse gas Emission Building (ZEB). The concept is redesigned based on comparing greenhouse gas (GHG) emission loads and compensation ...
  • Carbon Nanotube Spectrally Selective Solar Absorbers 

    Chen, Zhonghua; Nguyen, Quang Hong; Boström, Tobias (Journal article; Tidsskriftartikkel; Peer reviewed, 2015)
    The use of multi-walled carbon nanotubes (MWCNTs) as spectrally selective solar thermal absorbers (SSA) in solar thermal collectors is presented in this paper. CNT layers were coated by electrophoretic deposition (EPD) ...
  • Numerical Simulation of Microwave Scattering from Sea Ice Based on The Finite Element Method 

    Xu, Xu; Doulgeris, Anthony Paul; Melandsø, Frank; Brekke, Camilla (Journal article; Tidsskriftartikkel; Peer reviewed, 2016-11-03)
    In this paper, a 2-dimensional scattering model for sea ice based on the Finite Element Method (FEM) is presented. The scattering problem is formulated following a physics-separate strategy. The wave in the air domain is ...
  • Electrophoretically deposited carbon nanotube spectrally selective solar absorbers 

    Chen, Zhonghua; Boström, Tobias (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-11-11)
    Three types of carbon nanotubes(CNT) have been investigated regarding their suitability as spectrally selective solar thermal absorbers.The CNT coatings were electrophoretically deposited on aluminum substrates using ...
  • A comparative study of sea clutter covariance matrix estimators 

    Ding, Tao; Anfinsen, Stian Normann; Brekke, Camilla (Journal article; Tidsskriftartikkel; Peer reviewed, 2013-10-23)
    Estimation of the polarimetric covariance matrix is an important task in statistical modeling of sea clutter for maritime applications of polarimetric synthetic aperture radar (PolSAR) data. This work provides a comprehensive ...
  • Level crossings and excess times due to a superposition of uncorrelated exponential pulses 

    Theodorsen, Audun; Garcia, Odd Erik (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-01-10)
    A well-known stochastic model for intermittent fluctuations in physical systems is investigated. The model is given by a superposition of uncorrelated exponential pulses, and the degree of pulse overlap is interpreted as ...
  • Oil Spill Dispersion in Full-polarimetric and Hybrid-polarity SAR 

    Brekke, Camilla; Skrunes, Stine; Espeseth, Martine (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-12-04)
    We show that indications of spatial dispersion effects on mineral oil slicks are observed by space-borne multipolarization synthetic aperture radar. This is readily perceived by eye when correlating multipolarization ...

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