• Separable representations of the Poisson, Helmholtz and complex Helmholtz kernels 

      Bjørgve, Magnar (Master thesis; Mastergradsoppgave, 2017-02-15)
      For high accuracy applications of integral operators in higher dimensions the complexity of operation and storage usually grows exponentially with dimensions. One method that has proven successful for handling these difficulties are the separation of the integral kernels as linear combinations of products of one-dimensional kernels, commonly referred to as separation of variables. In this ...
    • Simplicial complexes, Demi-matroids, Flag of linear codes and pair of matroids. 

      Zubair, Ali (Master thesis; Mastergradsoppgave, 2015-05-15)
      We first describe linear error-correcting codes, and show how many of their most important properties are determined by their associated matroids . We also introduce the simplicial complex of the independent sets of a matroid. We then proceed to study flags of linear codes, and recall the definition of demi-matroids, and how such demi-matroids associated to flags can describe important properties ...
    • Symmetric Ideals 

      Lien, Arne (Mastergradsoppgave; Master thesis, 2021-05-14)
      Polynomials appear in many different fields such as statistics, physics and optimization. However, when the degrees or the number of variables are high, it generally becomes quite difficult to solve polynomials or to optimize polynomial functions. An approach that can often be helpful to reduce the complexity of such problems is to study symmetries in the problems. A relatively new field, that has ...
    • Symmetry transformation groups and differential invariants 

      Schneider, Eivind (Master thesis; Mastergradsoppgave, 2014-11-15)
      There exists a local classification of finite-dimensional Lie algebras of vector fields in two complex dimensions. We lift the Lie algebras from this classification to three complex dimensions.
    • Tipping points and crises in financial markets 

      Shemyakina, Polina (Master thesis; Mastergradsoppgave, 2015-05-15)
      Electricity spot markets and other financial markets are complex systems, and it is difficult to forecast their behaviour, especially uncontrolled and unmanageable situations, such as power crises and deflation of financial bubbles. An energy crisis is any price rise in the supply of energy resources to an economy. It has undesirable consequences, occasionally irreversible. The most known of these ...
    • Towers of Betti Numbers of Matroids and Weight Distribution of Linear Codes and their Duals 

      Huerga Represa, Violeta (Master thesis; Mastergradsoppgave, 2015-05-15)
      The main notion behind the study of matroids is linear dependence. In this thesis, we give a survey of the concepts and properties of linear error-correcting codes over finite fields being dependent only on the matroids derived from these codes. In particular, the weight distributions of linear codes, and their extensions, over bigger fields are only dependent on the N-graded Betti numbers of these ...
    • The Unidirectional Pulse Propagation Equation for Cylindrical Vector modes 

      Nilsen, Vegard (Master thesis; Mastergradsoppgave, 2015-07-27)
      A new model for the unidirectional pulse propagation equations (UPPE) was developed by Per Jacobsen[1], this model is based on the assumption of cylindrical vector (CV) modes. The model will be strong for CV type electrical eld representations where only a few modes will be excited. In this thesis we will investigate the model further. The model will be implemented as a pseudo spectral method where ...
    • The use of elliptic curves in cryptography 

      Juhas, Tibor (Master thesis; Mastergradsoppgave, 2007-06)
      The use of elliptic curves in cryptography was suggested independently by Neal Koblitz and Victor Miller in 1985. Being a relatively new field, there is still a lot of ongoing research on the subject, but elliptic curve cryptography, or ECC for short, has already been implemented in real-life applications. Its strength was proved in 2003 when the U.S. National Security Agency adopted ECC for protecting ...
    • Wachpress Conjecture Restricted To Arrangements Of Three Conics 

      Schena, Alessandro (Mastergradsoppgave; Master thesis, 2022-05-15)
      This thesis discusses Wachpress conjecture restricted to arrangements of three conics. Wachpress conjectured the existence of a set of barycentric coordinates, namely Wachpress coordinates, on all polycons. Barycentric coordinates are very useful in many different fields as they can be used to define a finite element approximation scheme with linear precision. This thesis focuses on the conjecture ...