Browsing Det matematisk-naturvitenskapelige fakultet by Title

Now showing items 81-100 of 19604

  • A (2,3)-complete intersection fourfold with no decomposition of the diagonal 
    Skauli, Bjørn (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
    We apply the specialization technique based on the decomposition of the diagonal to the intersection of a quadric and cubic hypersurface in P6. We find an explicit example defined over Q that is smooth, and does not admit ...
  • A (Dual) Network Model for Heat Transfer in Porous Media 
    Koch, Timo; Weishaupt, Kilian; Müller, Johannes; Weigand, Bernhard; Helmig, Rainer (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
    Abstract We present a dual network model to simulate coupled single-phase flow and energy transport in porous media including conditions under which local thermal equilibrium cannot be assumed. The models target applications ...
  • A 15-million-year-long record of phenotypic evolution in the heavily calcified coccolithophore Helicosphaera and its biogeochemical implications 
    Supraha, Luka; Henderiks, Jorijntje (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2020)
    The biogeochemical impact of coccolithophores is defined not only by their overall abundance in the oceans but also by wide ranges in physiological traits such as cell size, degree of calcification and carbon production ...
  • A 16-year record (2002–2017) of permafrost, active-layer, and meteorological conditions at the Samoylov Island Arctic permafrost research site, Lena River delta, northern Siberia: an opportunity to validate remote-sensing data and land surface, snow, and permafrost models 
    Boike, Julia; Nitzbon, Jan; Anders, Katharina; Grigoriev, Mikhail N; Bolshiyanov, Dimitri Yu.; Langer, Moritz; Lange, Stephan; Bornemann, Niko; Morgenstern, Anne; Schreiber, Peter; Wille, Christian; Chadburn, Sarah; Gouttevin, Isabelle; Burke, Eleanor; Kutzbach, Lars (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2019)
    Please read the corrigendum first, before the main paper. Most of the world's permafrost is located in the Arctic, where its frozen organic carbon content makes it a potentially important influence on the global climate ...
  • A 20-year record (1998–2017) of permafrost, active layer and meteorological conditions at a high Arctic permafrost research site (Bayelva, Spitsbergen) 
    Boike, Julia; Juszak, Inge; Lange, Stephan; Chadburn, Sarah; Burke, Eleanor; Paul Overduin, Pier; Roth, Kurt; Ippisch, Olaf; Bornemann, Niko; Stern, Lielle; Gouttevin, Isabelle; Hauber, Ernst; Westermann, Sebastian (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2018)
    Most permafrost is located in the Arctic, where frozen organic carbon makes it an important component of the global climate system. Despite the fact that the Arctic climate changes more rapidly than the rest of the globe, ...
  • A 23 m.y. record of low atmospheric CO2 
    Cui, Ying; Schubert, Brian A.; Jahren, Anne Hope (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2020)
    Abstract Current atmospheric CO2 concentration is known to be higher than it has been during the past ∼800 k.y. of Earth history, based on direct measurement of CO2 within ice cores. A comparison to the more ...
  • A Bayesian Approach to Smoothing and Forecasting Mortality RatesRestricted Access 
    Graff, Michael (Master thesis / Masteroppgave, 2014)
    The Icelandic population is scarce compared to the Norwegian, causing high variability in the observed mortalities. We apply two mortality models to data on the Norwegian population dating 60 years back, and the Icelandic ...
  • A Bayesian Binomial Regression Model with Latent Gaussian Processes for Modelling DNA Methylation 
    Hubin, Aliaksandr; Storvik, Geir Olve; Grini, Paul Eivind; Butenko, Melinka Alonso (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2020)
    Epigenetic observations are represented by the total number of reads from a given pool of cells and the number of methylated reads, making it reasonable to model this data by a binomial distribution. There are numerous ...
  • A benchmarking exercise for environmental contours 
    Haselsteiner, Andreas F.; Coe, Ryan G.; Manuel, Lance; Chai, Wei; Leira, Bernt Johan; Clarindo, Guilherme; Soares, Carlos Guedes; Hannesdóttir, Ásta; Dimitrov, Nikolay; Sander, Aljoscha; Ohlendorf, Jan-Hendrik; Thoben, Klaus-Dieter; Hauteclocque, Guillaume de; Mackay, Ed; Jonathan, Philip; Qiao, Chi; Myers, Andrew; Rode, Anna; Hildebrandt, Arndt; Schmidt, Boso; Vanem, Erik; Huseby, Arne Bang (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
    Environmental contours are used to simplify the process of design response analysis. A wide variety of contour methods exist; however, there have been a very limited number of comparisons of these methods to date. This ...
  • A biophysical study of the interactions between the antimicrobial peptide indolicidin and lipid model systems 
    Nielsen, Josefine Eilsø; Lind, Tania Kjellerup; Lone, Abdullah; Gerelli, Yuri; Hansen, Paul Robert; Jenssen, Håvard; Cardenas, Marite; Lund, Reidar (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2019)
    The naturally occurring peptide indolicidin from bovine neutrophils exhibits strong biological activity against a broad spectrum of microorganisms. This is believed to arise from selective interactions with the negatively ...
  • A bit of tropical geometry 
    Shaw, Kristin; Brugallé, Erwan (Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2014)
    This friendly introduction to tropical geometry is meant to be accessible to first year students in mathematics. The topics discussed here are basic tropical algebra, tropical plane curves, some tropical intersections, and ...
  • A boosting first-hitting-time model for survival analysis in high-dimensional settings 
    De Bin, Riccardo; Stikbakke, Vegard (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
    In this paper we propose a boosting algorithm to extend the applicability of a first hitting time model to high-dimensional frameworks. Based on an underlying stochastic process, first hitting time models do not require ...
  • A brain and a head for a different habitat: Size variation in four morphs of Arctic charr (Salvelinus alpinus (L.)) in a deep oligotrophic lake 
    Tamayo, Ana-Maria Peris; Devineau, Olivier; Præbel, Kim; Kahilainen, Kimmo Kalevi; Østbye, Kjartan (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2020)
    Adaptive radiation is the diversification of species to different ecological niches and has repeatedly occurred in different salmonid fish of postglacial lakes. In Lake Tinnsjøen, one of the largest and deepest lakes in ...
  • A breath of fresh air - Visualizing air quality 
    Rimer, Marte (Master thesis / Group thesis / Masteroppgave / Gruppeoppgave, 2020)
    This thesis presents a two-part research process exploring how to visualize the air quality for young adults living in Oslo. Through a user centered design process, we explore how technology can be used to visualize air ...
  • A breath of fresh air - Visualizing air quality for young adults 
    Hiorthøy, Jonas Haraldson (Master thesis / Group thesis / Masteroppgave / Gruppeoppgave, 2020)
    This thesis presents a two-part research process exploring how to visualize the air quality for young adults living in Oslo. Through a user-centered design process, we explore how technology can be used to visualize air ...
  • A broadly resolved molecular phylogeny of New Zealand cheilostome bryozoans as a framework for hypotheses of morphological evolution. 
    Orr, Russell John Scott; Di Martino, Emanuela; Gordon, Dennis P.; Ramsfjell, Mali Hamre; Mello, Hannah; Smith, Abigail M.; Liow, Lee Hsiang (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
    Larger molecular phylogenies based on ever more genes are becoming commonplace with the advent of cheaper and more streamlined sequencing and bioinformatics pipelines. However, many groups of inconspicuous but no less ...
  • A Case Study on Technical DebtRestricted Access 
    Afzal, Zunaira (Master thesis / Masteroppgave, 2018)
    The topic of this thesis is technical debt in concern to two IT projects from the Norwegian Meteorological Institute
  • A Case-Study of Automated Feedback Assessment 
    Mirmotahari, Omid; Berg, Yngvar; Gjessing, Stein; Fremstad, Ester; Damsa, Crina I. (Journal article / Tidsskriftartikkel / SubmittedVersion, 2019)
    This study was conducted in a first year university course in computer programming. We investigated how the use of a digital assessment tool, consisting of quantitative weighting and which simultaneously generate qualitative ...
  • A censored shifted mixture distribution mapping method to correct the bias of daily IMERG satellite precipitation estimates 
    Ma, Qiumei; Xiong, Lihua; Xia, Jun; Xiong, Bin; Yang, Han; Xu, Chong-Yu (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2019)
    Satellite precipitation estimates (SPE) provide useful input for hydrological modeling. However, hydrological modeling is frequently hindered by large bias and errors in SPE, inducing the necessity for bias corrections. ...
  • A characterization of supersmoothness of multivariate splines 
    Floater, Michael S. (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2020)
    We consider spline functions over simplicial meshes in Rn. We assume that the spline pieces join together with some finite order of smoothness but the pieces themselves are infinitely smooth. Such splines can have extra ...