Search for dissertations about: "Symmetry and equations"

Showing result 1 - 5 of 52 swedish dissertations containing the words Symmetry and equations.

  1. 1. Polynomial Solvers for Geometric Problems - Applications in Computer Vision and Sensor Networks

    Author : Yubin Kuang; Matematik LTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; polynomial solver; geometric problems; computer vision; sensor networks; symmetry;

    Abstract : Given images of a scene taken by a moving camera or recordings of a moving smart phone playing a song by a microphone array, how hard is it to reconstruct the scene structure or the moving trajectory of the phone? In this thesis, we study and solve several fundamental geometric problems in order to provide solutions to these problems. The key underlying technique for solving such geometric problems is solving systems of polynomial equations. READ MORE

  2. 2. Strong Cosmic Censorship and Cosmic No-Hair in spacetimes with symmetries

    Author : Katharina Maria Radermacher; Hans Ringström; James Isenberg; KTH; []
    Keywords : NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Cosmic Censorship; Cosmic No-Hair; Big Bang; symmetry; Bianchi; T2-symmetry; Gowdy; general relativity; cosmology; late time; initial time; asymptotic behaviour; perfect fluid; scalar field; Einstein equations; Mathematics; Matematik;

    Abstract : This thesis consists of three articles investigating the asymptotic behaviour of cosmological spacetimes with symmetries arising in Mathematical General Relativity.In Paper A and B, we consider spacetimes with Bianchi symmetry and where the matter model is that of a perfect fluid. READ MORE

  3. 3. Essays on Consumption : - Aggregation, Asymmetry and Asset Distributions

    Author : Mårten Bjellerup; Jan Ekberg; Katarina Juselius; Växjö universitet; []
    Keywords : SOCIAL SCIENCES; SAMHÄLLSVETENSKAP; SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; Aggregate consumption; Aggregation; Asymmetry; Wealth distribution; Income distribution; Concavity; Permanent Income Hypothesis; Buffer stock saving; Precautionary saving; consumption; saving; Euler equation; error correction; skew-t distribution; gamma distribution; dispersion; non-linear model; durable goods; nondurable goods; household level data; consumption function; marginal propensity to consume; current resources; consumption expenditure; life-cycle model; univariate test; multivariate test; Sweden; Economics; Nationalekonomi; Economics; Nationalekonomi;

    Abstract : The dissertation consists of four self-contained essays on consumption. Essays 1 and 2 consider different measures of aggregate consumption, and Essays 3 and 4 consider how the distributions of income and wealth affect consumption from a macro and micro perspective, respectively. READ MORE

  4. 4. Design of High Performance Computing Software for Genericity and Variability

    Author : Malin Ljungberg; Michael Thuné; Kurt Otto; Hans Petter Langtangen; Uppsala universitet; []
    Keywords : NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; PDE solver; high-performance; coordinate invariant; curvilinear coordinates; symmetry exploiting; generalized Fourier transform; finite difference; expression templates; feature modeling; variability; Beräkningsvetenskap; Scientific Computing;

    Abstract : Computer simulations have emerged as a cost efficient complement to laboratory experiments, as computers have become increasingly powerful. The aim of the present work is to explore the ideas of some state of the art software development practices, and ways in which these can be useful for developing high performance research codes. READ MORE

  5. 5. Spontaneous and stimulated X-ray Raman scattering

    Author : Yu-Ping Sun; Faris Gel'mukhanov; Vincenzo Carravetta; KTH; []
    Keywords : NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; NATURAL SCIENCES; resonant X-ray scattering; resonant Auger scattering; rotational Doppler broadening; XFEL pulse; Atomic and molecular physics; Atom- och molekylfysik; Spectroscopy; Spektroskopi;

    Abstract : The present thesis is devoted to theoretical studies of resonant X-ray scattering and propagation of strong X-ray pulses. In the first part of the thesis the nuclear dynamics of different molecules is studied using resonant X-ray Raman and resonant Auger scattering techniques. READ MORE