Sökning: "Padé approximation"

Visar resultat 1 - 5 av 9 avhandlingar innehållade orden Padé approximation.

  1. 1. Adaptive methods in computational electromagnetics

    Författare :Pär Ingelström; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; finite elements; hybris methods; finite-difference time-domain; error estimation; mesh refinement; Padé approximation;

    Sammanfattning : .... LÄS MER

  3. 2. Multipoint Padé approximants used for piecewise rational interpolation and for interpolation to functions of Stieltjes' type

    Författare :Jan Gelfgren; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Continued fractions; Hardy space; Padé approximant; series of Stieltjes;

    Sammanfattning : A multipoint Padë approximant, R, to a function of Stieltjes1 type is determined.The function R has numerator of degree n-l and denominator of degree n.The 2n interpolation points must belong to the region where f is analytic,and if one non-real point is amongst the interpolation points its complex-conjugated point must too. LÄS MER

  4. 3. Theoretical methods for the electronic structure and magnetism of strongly correlated materials

    Författare :Inka L. M. Locht; Igor Di Marco; Silke Biermann; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; dynamical mean field theory DMFT ; Hubbard I approximation; strongly correlated systems; rare earths; lanthanides; photoemission spectra; ultrafast magnetization dynamics; analytic continuation; Padé approximant method; two-particle Green s functions; linear muffin tin orbitals LMTO ; density functional theory DFT ; cerium; stacking fault energy.; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

    Sammanfattning : In this work we study the interesting physics of the rare earths, and the microscopic state after ultrafast magnetization dynamics in iron. Moreover, this work covers the development, examination and application of several methods used in solid state physics. The first and the last part are related to strongly correlated electrons. LÄS MER

  5. 4. Periodized Thermal Greens Functions and Applications

    Författare :Andro Sabashvili; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; condensed matter physics; Greens function; graphene; DMFT; RPA; GW;

    Sammanfattning : This work describes a new formalism for Fermionic thermal Greens functions that are discretized in imaginary time. The discretization makes the thermal Greens function periodic in imaginary (Matsubara) frequency space and requires a generalisation of the Dyson equation and Luttinger-Ward-Baym-Kadanoff functional. LÄS MER

  7. 5. Heterogeneous Materials - Diffusion, Laplace spectrum and NMR

    Författare :Matias Nordin; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; perturbation; nmr; diffusion; laplace operator; spectrum; heterogeneous materials;

    Sammanfattning : Relations to the effective diffusion constant and the relaxation rate of the time-dependent diffusion coefficient for porous systems are derived from the Laplace operator spectrum. The Padé approximation is then explained in terms of the Laplace operator spectrum. LÄS MER