Now showing items 21-40 of 1454

    • Solitons of general topological charge over noncommutative tori 

      Dabrowski, Ludwik; Jakobsen, Mads Sielemann; Landi, Giovanni; Luef, Franz (Peer reviewed; Journal article, 2021)
      We study solitons of general topological charge over noncommutative tori from the perspective of time-frequency analysis. These solitons are associated with vector bundles of higher rank, expressed in terms of vector-valued ...
    • Effect of convective mixing process on storage of CO2 in saline aquifers with layered permeability. 

      Taheri, Amir; Torsæter, Ole; Lindeberg, Erik Gøsta Brun; Hadia, Nanji; Wessel-Berg, Dag (Journal article, 2021)
      Convective mixing of free-phase CO2 and brine in saline aquifers is an established technique to accelerate the CO2 dissolution process. Correct estimation of the convection onset time and rate of CO2 dissolution into brine ...
    • Robust Modelling of Additive and Non-additive Variation with Intuitive Inclusion of Expert Knowledge 

      Hem, Ingeborg Gullikstad; Selle, Maria; Gorjanc, Gregor; Fuglstad, Geir-Arne; Riebler, Andrea Ingeborg (Peer reviewed; Journal article, 2020)
      We propose a novel Bayesian approach that robustifies genomic modeling by leveraging expert knowledge (EK) through prior distributions. The central component is the hierarchical decomposition of phenotypic variation into ...
    • Hierarchical Identity-Based Encryption with Tight Multi-challenge Security 

      Langrehr, Roman; Pan, Jiaxin (Peer reviewed; Journal article, 2020)
      We construct the first hierarchical identity-based encryption (HIBE) scheme with tight adaptive security in the multi-challenge setting, where adversaries are allowed to ask for ciphertexts for multiple adaptively chosen ...
    • Unbounded HIBE with Tight Security 

      Langrehr, Roman; Pan, Jiaxin (Peer reviewed; Journal article, 2020)
      We propose the first tightly secure and unbounded hierarchical identity-based encryption (HIBE) scheme based on standard assumptions. Our main technical contribution is a novel proof strategy that allows us to tightly ...
    • Tightly Secure Hierarchical Identity-Based Encryption 

      Langrehr, Roman; Pan, Jiaxin (Peer reviewed; Journal article, 2020)
      We construct the first tightly secure hierarchical identity-based encryption (HIBE) scheme based on standard assumptions, which solves an open problem from Blazy, Kiltz, and Pan (CRYPTO 2014). At the core of our constructions ...
    • Pair Correlation estimates for the zeros of the zeta function via semidefinite programming 

      Chirre, Andrés; Gonçalves, Felipe; De Laat, David (Peer reviewed; Journal article, 2020)
      In this paper we study the distribution of the non-trivial zeros of the Riemann zeta-function ζ(s) (and other L-functions) using Montgomery's pair correlation approach. We use semidefinite programming to improve upon ...
    • A second-order numerical method for the aggregation equations 

      Solem, Susanne; Fjordholm, Ulrik Skre; Carrillo, José A (Peer reviewed; Journal article, 2020)
      Abstract: Inspired by so-called TVD limiter-based second-order schemes for hyperbolic conservation laws, we develop a formally second-order accurate numerical method for multi-dimensional aggregation equations. The method ...
    • Solitary waves for weakly dispersive equations with inhomogeneous nonlinearities 

      Mæhlen, Ola Isaac Høgåsen (Peer reviewed; Journal article, 2020)
    • A 2-dimensional shape optimization problem for tree branches 

      Bressan, Alberto; Galtung, Sondre Tesdal (Peer reviewed; Journal article, 2020)
      The paper is concerned with a shape optimization problem, where the functional to be maximized describes the total sunlight collected by a distribution of tree leaves, minus the cost for transporting water and nutrient ...
    • Design- and Model-Based Approaches to Small-Area Estimation in a Low and Middle Income Country Context: Comparisons and Recommendations 

      Paige, John; Fuglstad, Geir-Arne; Riebler, Andrea Ingeborg; Wakefield, Jon (Peer reviewed; Journal article, 2020)
      The need for rigorous and timely health and demographic summaries has provided the impetus for an explosion in geographic studies in low- and middle-income countries. Many of these studies present fine-scale pixel-level ...
    • Rational local systems and connected finite loop spaces 

      Heard, Drew Kenneth (Peer reviewed; Journal article, 2021)
      Greenlees has conjectured that the rational stable equivariant homotopy category of a compact Lie group always has an algebraic model. Based on this idea, we show that the category of rational local systems on a connected ...
    • Source Conditions for Non-Quadratic Tikhonov Regularization 

      Grasmair, Markus (Peer reviewed; Journal article, 2020)
      In this paper, we consider convex Tikhonov regularization for the solution of linear operator equations on Hilbert spaces. We show that standard fractional source conditions can be employed in order to derive convergence ...
    • Matrix factorizations for self-orthogonal categories of modules 

      Bergh, Petter Andreas; Thompson, Peder (Peer reviewed; Journal article, 2020)
      For a commutative ring S and self-orthogonal subcategory C of Mod(S), we consider matrix factorizations whose modules belong to C. Let f∈S be a regular element. If f is M-regular for every M∈C, we show there is a natural ...
    • The third Milgram--Priddy class lifts 

      Szymik, Markus (Peer reviewed; Journal article, 2020)
      Abstract: We show that the third cohomology of the finite general linear group with trivial mod 2 coefficients is non-zero. The necessarily unique non-trivial element restricts to the third Milgram–Priddy class.
    • Digital Competences for Language Teachers: Do Employers Seek the Skills Needed from Language Teachers Today? 

      Talmo, Tord Mjøsund; Soule, Maria Victoria; Fominykh, Mikhail; Giordano, Antonio; Perifanou, Maria; Suckacke, Vilma; Novozhilova, Anna; D'Ambrosio, Roberta; Elçi, Alev (Peer reviewed; Journal article, 2020)
      Language proficiency is essential for 21st Century skills, and for the ability to obtain and utilize new competencies in the future. Digitalization is greatly affecting the language learning settings, and more digital ...
    • A multimesh finite element method for the Navier–Stokes equations based on projection methods 

      Dokken, Jørgen; Johansson, August; Massing, André; Funke, Simon Wolfgang (Peer reviewed; Journal article, 2020)
      The multimesh finite element method is a technique for solving partial differential equations on multiple non-matching meshes by enforcing interface conditions using Nitsche’s method. Since the non-matching meshes can ...
    • Competing Risks Modeling by Extended Phase-Type Semi-Markov Distributions 

      Garcia-Maya, Brenda; Limnios, N.; Lindqvist, Bo Henry (Peer reviewed; Journal article, 2021)
      We present competing risks models within a semi-Markov process framework via the semi-Markov phase-type distribution. We consider semi-Markov processes in continuous and discrete time with a finite number of transient ...
    • Development of environmental contours for first-year ice ridge statistics 

      Chai, Wei; Leira, Bernt Johan; Næss, Arvid; Høyland, Knut Vilhelm; Ehlers, Sören (Peer reviewed; Journal article, 2020)
      Ice ridges represent a major threat to ships and offshore structures in areas with sea ice but no icebergs, since they frequently determine and govern the structural design loads. This work focuses on the development of ...
    • On support varieties and tensor products for finite dimensional algebras 

      Bergh, Petter Andreas; Sandøy, Mads Hustad; Solberg, Øyvind (Peer reviewed; Journal article, 2020)
      It has been asked whether there is a version of the tensor product property for support varieties over finite dimensional algebras defined in terms of Hochschild cohomology. We show that in general no such version can ...