Sökning: "wave equation"

Visar resultat 11 - 15 av 96 uppsatser innehållade orden wave equation.

  1. 11. Finita differensapproximationer av tvådimensionella vågekvationen med variabla koefficienter

    Kandidat-uppsats,

    Författare :Herman Bergkvist; [2023]
    Nyckelord :Finite Difference Methods; SBP-SAT; Wave Equation; Variable Coefficients; Finita differensmetoden; SBP–SAT; vågekvationen; variabla koefficienter;

    Sammanfattning : I [Mattson, Journal of Scientific Computing 51.3 (2012), s. 650–682] konstruerades partialsummeringsoperatorer för finita differensapproximationer av andraderivator med variabla koefficienter. LÄS MER

  3. 12. Beyond the Gross-Pitaevskii Equation: A Perturbative Approach

    Master-uppsats, Lunds universitet/Fysiska institutionen; Lunds universitet/Teknisk fysik (CI)

    Författare :Anton Johansson; [2023]
    Nyckelord :Gross-Pitaevskii; Beyond mean-field; Many-body Perturbation Theory; Bose-Einstein Condensate; BEC; Physics and Astronomy;

    Sammanfattning : We propose and implement a beyond Gross-Pitaevskii approach based on Many-Body Perturbation theory (MBPT) for the study of Bose-Einstein Condensate (BECs) ground states. Two partitions of the system Hamiltonian are considered. LÄS MER

  4. 13. Open quantum systems

    Kandidat-uppsats, KTH/Skolan för teknikvetenskap (SCI)

    Författare :Anton Granlund Gustafsson; [2023]
    Nyckelord :quantum physics; quantum mechanics; open quantum systems; Lindblad equation; density matrix theory; qubit;

    Sammanfattning : In this Bachelor thesis project, the Lindblad master equation is derived, both as the most general way of modeling interaction with an environment that lacks memory, and through microscopic derivations focused on assumptions about the way the system interacts with its environment (weak-coupling, Born-Markov and rotating wave approximations). It is then applied to a two-level system (qubit). LÄS MER

  5. 14. Computation of Underwater Acoustic Wave Propagation Using the WaveHoltz Iteration Method

    Master-uppsats, KTH/Skolan för elektroteknik och datavetenskap (EECS)

    Författare :Paul Wall; [2022]
    Nyckelord :WaveHoltz iteration method; Helmholtz equation; Discontinuous Galerkin methods; Underwater acoustics.; WaveHoltziterativametod; Helmholtzekvation; DiskontinuerligaGalerkinmetoder; Undervattensakustik.;

    Sammanfattning : In this thesis, we explore a novel approach to solving the Helmholtz equation,the WaveHolz iteration method. This method aims to overcome some ofthe difficulties with solving the Helmholtz equation by providing a highlyparallelizable iterative method based on solving the time-dependent Waveequation. LÄS MER

  7. 15. One-Dimensional Velocity Distributions of Fast Ions under RF Heating Including Doppler Shift in Tokamaks

    Master-uppsats, KTH/Skolan för elektroteknik och datavetenskap (EECS)

    Författare :Lukas Bähner; [2022]
    Nyckelord :plasma; fusion; ICRH; Ion Cyclotron Resonance Heating; RF; radio frequency; Fokker-Planck equation; Fokker-Planck solver; quasilinear operator; Coulomb collision; Doppler shift; velocity distribution; local temperature; plasma; fusion; ICRH; joncyklotronuppvärmning; RF; radiofrekvens; Fokker-Planck-ekvationen; Fokker-Planck-lösare; kvasilinjär operator; Coulombkollisioner; Dopplerskift; hastighetsfördelning; lokal temperatur;

    Sammanfattning : The goal of nuclear fusion research is to create a clean and virtually limitless energy source. In order to that, a plasma must be heated to hundreds of millions degrees Celsius. A commonly used heating mechanism is ion cyclotron resonance heating, where antennas emit radio waves into the plasma. LÄS MER