Sökning: "Riemannian"

Visar resultat 1 - 5 av 9 uppsatser innehållade ordet Riemannian.

  1. 1. Spatial Statistical Modelling of Insurance Claim Frequency

    Master-uppsats, Lunds universitet/Matematisk statistik

    Författare :Daniel Faller; [2022]
    Nyckelord :Insurance risk; claim frequency; Markov chain Monte Carlo MCMC ; Riemann manifold Metropolis adjusted Langevin algorithm MMALA ; spatial statistics; Gaussian Markov random field GMRF ; preconditioned Crank Nicolson Langevin algorithm pCNL ; Gibbs sampling; Bayesian hierarchical modelling; high dimensional; shrinkage prior; horseshoe prior; regularisation.; Mathematics and Statistics;

    Sammanfattning : In this thesis a fully Bayesian hierarchical model that estimates the number of aggregated insurance claims per year for non-life insurances is constructed using Markov chain Monte Carlo based inference with Riemannian Langevin diffusion. Some versions of the model incorporate a spatial effect, viewed as the relative spatial insurance risk that originates from a policyholder's geographical location and where the relative spatial insurance risk is modelled as a continuous spatial field. LÄS MER

  3. 2. General Relativity and Dynamical Universes

    Kandidat-uppsats, Uppsala universitet/Teoretisk fysik

    Författare :Kajsa Fransson; [2021]
    Nyckelord :cosmology; general relativity; scale factor; friedmann equation;

    Sammanfattning : The aim of this report is to explore different models of cosmology, depending on components as matter, radiation and dark energy. To be able to investigate the behaviour and age of these model universes, it is necessary to solve the Friedmann equation. LÄS MER

  4. 3. The Existence of Riemannian Metrics on Real Vector Bundles

    Kandidat-uppsats, Umeå universitet/Institutionen för matematik och matematisk statistik

    Författare :Jan-Ola Collin; [2018]
    Nyckelord :;

    Sammanfattning : In this thesis we present a self-contained proof of the existence of Riemannian metrics on real vector bundles. ... LÄS MER

  5. 4. Unstructured mesh adaptation for turbo-machinery RANS computation

    Master-uppsats, KTH/Flygdynamik

    Författare :Marc-Antoine Bouvattier; [2017]
    Nyckelord :Metric tensor; mesh adaptation; anisotropy; projection error; turbo-machinery; unstructured mesh; Riemannian;

    Sammanfattning : This paper gives an overview of the mathematical and practical tools that can be used in turbo-machinery RANS simulation to realize unstructured mesh adaptation. It first presents the concept of metric and recalls that the hessian of the physical flow properties can become, thanks to small modifications, both a metric and a upper bound of the P1 projection error. LÄS MER

  7. 5. Lie-teori och nästan kommutativa fält

    Kandidat-uppsats, Örebro universitet/Institutionen för naturvetenskap och teknik

    Författare :Malte Litsgård; [2016]
    Nyckelord :Lie-grupp; Lie-algebra; vektorfält; kommutativitet; Riemanngeometri.;

    Sammanfattning : Vi ger en överskådlig introduktion till mångfalder, Lie-grupper och deras associerade Lie-algebror. En karaktärisering av Lie-parentesen som naturligt kopplar ihop de vanligast förekommande karaktäriseringarna presenteras (sats 4.4.1). LÄS MER