Viser treff 660-679 av 942

    • Preliminary Assessment of Remote Wind Sites 

      Bilal, Muhammad; Araya, Guillermo; Birkelund, Yngve (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-08)
      Wind energy is becoming a reliable and affordable source of clean energy and is rapidly expanding to remote places around the world. A crucial input for wind farming prospect is the assessment of potential wind sites. Sites, especially remotely located, often do not have a wind resource map and thus lack credible historical records of wind resources. Measurement campaigns to map these sites are ...
    • Probabilistic forecasts of wind power generation in regions with complex topography using deep learning methods: An Arctic case 

      Foldvik Eikeland, Odin; Hovem, Finn Dag; Olsen, Tom Eirik; Chiesa, Matteo; Bianchi, Filippo Maria (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-05-27)
      The energy market relies on forecasting capabilities of both demand and power generation that need to be kept in dynamic balance. Nowadays, contracts and auctions of renewable energy in a liberalized electricity market heavily rely on forecasting future power generation. The highly intermittent nature of renewable energy sources increases the uncertainty about future power generation. Since point ...
    • A probabilistic framework for source localization in anisotropic composite using transfer learning based multi-fidelity physics informed neural network (mfPINN) 

      Kalimullah, Nur M.-M.; Shelke, Amit; Habib, Anowarul (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-04-17)
      The practical application of data-driven frameworks like deep neural network in acoustic emission (AE) source localization is impeded due to the collection of significant clean data from the field. The utility of the such framework is governed by data collected from the site and/or laboratory experiment. The noise, experimental cost and time consuming in the collection of data further worsen the ...
    • Probability distribution functions for intermittent scrape-off layer plasma fluctuations 

      Theodorsen, Audun; Garcia, Odd Erik (Journal article; Peer reviewed; Tidsskriftartikkel, 2018-01-24)
      A stochastic model for intermittent fluctuations in the scrape-off layer of magnetically confined plasmas has been constructed based on a super-position of uncorrelated pulses arriving according to a Poisson process. In the most common applications of the model, the pulse amplitudes are assumed exponentially distributed, supported by conditional averaging of large-amplitude fluctuations in experimental ...
    • Probing power laws in multifrequency AFM 

      Santos Hernandez, Sergio; Gadelrab, Karim; Olukan, Tuza Adeyemi; Font, Josep; Barcons, Victor; Chiesa, Matteo (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-02-17)
      Quantification of conservative forces in multifrequency atomic force microscopy requires solving the general equations of the theory expressed in terms of the virials of interaction. Power law expressions are commonly utilized when dealing with electrostatic, ferroelectric, magnetic, or long range (van der Waals) forces. Here, we discuss long range forces modeled in terms of power laws (n), where ...
    • A procedure to correct the effects of a relative delay between the quadrature components of radar signals at base band. 

      Westman, A.; Grydeland, Tom; Belyey, Vasyl; La Hoz, Cesar (Journal article; Peer reviewed; Tidsskriftartikkel, 2005-01-31)
      The real and imaginary parts of baseband signals are obtained from a real narrow–band signal by quadrature mixing, i.e. by mixing with cosine and sine signals at the narrow band’s selected center frequency. We address the consequences of a delay between the outputs of the quadrature mixer, which arise when digital samples of the quadrature baseband signals are not synchronised, i.e. when ...
    • Productive detours – Atlantic water inflow and acoustic backscatter in the major troughs along the Svalbard shelf 

      Menze, Sebastian; Ingvaldsen, Randi Brunvær; Nikolopoulos, Anna; Hattermann, Tore; Albretsen, Jon; Gjøsæter, Harald (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-09-30)
      Atlantic Water (AW) flowing along the western and northern Svalbard shelf-break extends the Atlantic domain into the Arctic and is the region’s major source of heat, nutrients and advected plankton. We investigated the inflow and recirculation of AW into four major troughs that cut into the Svalbard shelf, the Isfjorden, Kongsfjorden, Hinlopen and Kvitøya Troughs, and related the circulation patterns ...
    • Pronounced Suppression and X-Pattern Merging of Equatorial Ionization Anomalies After the 2022 Tonga Volcano Eruption 

      Aa, Ercha; Zhang, Shun-Rong; Wang, Wenbing; Erickson, Philip J.; Qian, Liying; Eastes, Richard W.; Harding, Brian; Immel, Thomas; Karan, Deepak; Daniell, Robert E.; Coster, Anthea J.; Goncharenko, Larisa P.; Vierinen, Juha; Cai, Xuguang; Spicher, Andres (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-05-27)
      Following the 2022 Tonga Volcano eruption, dramatic suppression and deformation of the equatorial ionization anomaly (EIA) crests occurred in the American sector ∼14,000 km away from the epicenter. The EIA crests variations and associated ionosphere-thermosphere disturbances were investigated using Global Navigation Satellite System total electron content data, Global-scale Observations of the ...
    • Properties and dynamics of mesoscale eddies in Fram Strait from a comparison between two high-resolution ocean-sea ice models 

      Wekerle, Claudia; Hattermann, Tore; Wang, Qiang; Crews, Laura; von Appen, Wilken-Jon; Danilov, Sergey (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-10-23)
      Fram Strait, the deepest gateway to the Arctic Ocean, is strongly influenced by eddy dynamics. Here we analyse the output from two eddy-resolving models (ROMS – Regional Ocean Modeling System; FESOM – Finite-Element Sea-ice Ocean Model) with around 1 km mesh resolution in Fram Strait, with a focus on their representation of eddy properties and dynamics. A comparison with mooring observations shows ...
    • A Protocol for Single-Molecule Translation Imaging in Xenopus Retinal Ganglion Cells 

      Ströhl, Florian; Lin, Julie Qiaojin; Tartwijk, Francesca W. van; Wong, Hovy Ho Wai; Holt, Christine E.; Kaminski, Clemens F. (Chapter; Bokkapittel, 2020-04-29)
      Single-molecule translation imaging (SMTI) is a straightforward technique for the direct quantification of local protein synthesis. The protein of interest is fused to a fast-folding and fast-bleaching fluorescent protein, allowing one to monitor the appearance of individual fluorescence events after photobleaching of pre-existing proteins in the cell under investigation. The translation of individual ...
    • ProtoVAE: A Trustworthy Self-Explainable Prototypical Variational Model 

      Gautam, Srishti; Boubekki, Ahcene; Hansen, Stine; Salahuddin, Suaiba Amina; Jenssen, Robert; Hohne, Marina Marie-Claire; Kampffmeyer, Michael (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-10-15)
      The need for interpretable models has fostered the development of self-explainable classifiers. Prior approaches are either based on multi-stage optimization schemes, impacting the predictive performance of the model, or produce explanations that are not transparent, trustworthy or do not capture the diversity of the data. To address these shortcomings, we propose ProtoVAE, a variational autoencoder-based ...
    • Pulsating aurora and cosmic noise absorption associated with growth-phase arcs 

      McKay, Derek; Partamies, Noora; Vierinen, Juha (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-01-18)
      The initial stage of a magnetospheric substorm is the growth phase, which typically lasts 1–2 h. During the growth phase, an equatorward moving, east–west extended, optical auroral arc is observed. This is called a growth-phase arc. This work aims to characterize the optical emission and riometer absorption signatures associated with growth-phase arcs of isolated substorms. This is done using ...
    • The pulsation modes of the pre-white dwarf PG 1159-035 

      Costa, J. E. S.; Solheim, Jan Erik; Kepler, S. O.; Winget, D. E.; O’Brien, M. S.; Kawaler, S. D.; Costa, A. F. M.; Giovannini, O.; Kanaan, A.; Mukadam, A. S.; Mullally, F.; Nitta, A.; Provenc, J. L.; Shipman, H.; Wood, M. A.; Ahrens, T. J.; Grauer, A.; Kilic, M.; Bradley, P. A.; Sekiguchi, K.; Crowe, R.; Jiang, X. J.; Sullivan, D.; Sullivan, T.; Rosen, R.; Clemens, J. C.; Janulis, R.; O’Donoghue, D.; Ogloza, W.; Baran, A.; Silvotti, R.; Marinoni, S.; Vauclair, G.; Dolez, N.; Chevreton, M.; Dreizler, S.; Schuh, S.; Deetjen, J.; Nagel, T.; Gonzalez Perez, J. M.; Ulla, A.; Barstow, Martin; Burleigh, M.; Good, S.; Metcalfe, T.S.; Kim, S.-L.; Lee, H.; Sergeev, A.; Akan, M.C.; Çakırlı, Ö.; Paparo, M.; Viraghalmy, G.; Ashoka, B. N.; Handler, G.; Hürkal, Özlem; Johannessen, F.; Kleinman, S. J.; Kalytis, R.; Krzesinski, J.; Klumpe, E.; Larrison, J.; Lawrence, T.; Meištas, E.; Martinez, P.; Nather, R. E.; Fu, J.-N.; Pakštienė, E.; Rosen, R.; Romero-Colmenero, E.; Riddle, R.; Seetha, S.; Silvestri, N. M.; Vučković, M.; Warner, B.; Zola, S.; Althaus, L. G.; Córsico, A. H.; Montgomery, M. H. (Journal article; Tidsskriftartikkel; Peer reviewed, 2008)
      Context. PG 1159-035, a pre-white dwarf with Teff ≃ 140 000 K, is the prototype of both two classes: the PG 1159 spectroscopic class and the DOV pulsating class. Previous studies of PG 1159-035 photometric data obtained with the Whole Earth Telescope (WET) showed a rich frequency spectrum allowing the identification of 122 pulsation modes. Analyzing the periods of pulsation, it is possible to ...
    • Quad-Polarimetric SAR for Detection and Characterization of Icebergs 

      Akbari, Vahid; Brekke, Camilla; Doulgeris, Anthony Paul; Storvold, Rune; Sivertsen, Agnar H. (Conference object; Konferansebidrag, 2016)
      This paper evaluates the performance of fully polarimetric SAR data in iceberg detection and characterization. The study aims to explore the potential of RADARSAT-2 SAR data to detect icebergs and growlers in Svalbard that have broken off from the glaciers nearby. To be able to detect iceberg/growlers in a SAR image, a significant contrast between iceberg and background clutter is required. The ...
    • Quantification of the NA dependent change of shape in the image formation of a z-polarised fluorescent molecule using vectorial diffraction simulations 

      Ströhl, Florian; Bruggeman, Ezra; Rowlands, Christopher; Wolfson, Deanna; Ahluwalia, Balpreet Singh (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-01-19)
      The point spread function of a fixed fluorophore with its dipole axis colinear to the optical axis appears donut-shaped when seen through a microscope, and its light distribution in the pupil plane is radially polarized. Yet other techniques, such as photolithography, report that this same light distribution in the pupil plane appears as a solid spot. How can this same distribution lead to a spot ...
    • Quantification of van der Waals forces in bimodal and trimodal AFM 

      Santos Hernandez, Sergio; Gadelrab, Karim; Elsherbiny, Lamiaa; Drexler, Xaver; Olukan, Tuza Adeyemi; Font, Josep; Barcons, Victor; Chiesa, Matteo (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-05-22)
      The multifrequency formalism is generalized and exploited to quantify attractive forces, i.e., van der Waals interactions, with small amplitudes or gentle forces in bimodal and trimodal atomic force microscopy (AFM). The multifrequency force spectroscopy formalism with higher modes, including trimodal AFM, can outperform bimodal AFM for material property quantification. Bimodal AFM with the second ...
    • Quantitative assessment of morphology and sub-cellular changes in macrophages and trophoblasts during inflammation 

      Singh, Rajwinder; Dubey, Vishesh; Wolfson, Deanna; Ahmad, Azeem; Butola, Ankit; Acharya, Ganesh; Singh Mehta, Dalip; Basnet, Purusotam; Ahluwalia, Balpreet Singh (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-06-12)
      In pregnancy during an inflammatory condition, macrophages present at the feto-maternal junction release an increased amount of nitric oxide (NO) and pro-inflammatory cytokines such as TNF-α and INF-γ, which can disturb the trophoblast functions and pregnancy outcome. Measurement of the cellular and sub-cellular morphological modifications associated with inflammatory responses are important in order ...
    • Quantitative assessment of two oil-in-ice surface drift algorithms 

      Martins de Aguiar, Victor Cesar; Dagestad, Knut-Frode; Hole, Lars Robert; Barthel, Knut Sven (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-02-04)
      The ongoing reduction in extent and thickness of sea ice in the Arctic might result in an increase of oil spill risk due to the expansion of shipping activity and oil exploration shift towards higher latitudes. This work assessed the response of two oil-in-ice surface drift models implemented in an open-source Lagrangian framework. By considering two numerical modeling experiments, our main finding ...
    • Quantitative phase microscopy of red blood cells during planar trapping and propulsion 

      Ahmad, Azeem; Dubey, Vishesh; Singh, Vijay; Tinguely, Jean-Claude; Øie, Cristina Ionica; Wolfson, Deanna; Mehta, Dalip Singh; So, Peter T. C.; Ahluwalia, Balpreet Singh (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-08-22)
      Red blood cells (RBCs) have the ability to undergo morphological deformations during microcirculation, such as changes in surface area, volume and sphericity. Optical waveguide trapping is suitable for trapping, propelling and deforming large cell populations along the length of the waveguide. Bright field microscopy employed with waveguide trapping does not provide quantitative information about ...
    • Quasi Monte Carlo time-frequency analysis 

      Levie, Ron; Avron, Haim; Kutyniok, Gitta Astrid Hildegard (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-09-30)
      We study signal processing tasks in which the signal is mapped via some generalized time-frequency transform to a higher dimensional time-frequency space, processed there, and synthesized to an output signal. We show how to approximate such methods using a quasi-Monte Carlo (QMC) approach. We consider cases where the time-frequency representation is redundant, having feature axes in addition to the ...