Essays about: "dft"

Showing result 1 - 5 of 105 essays containing the word dft.

  1. 1. Implementation of Dyson equation to accelerate convergence in RS-LMTO-ASA code

    University essay from Uppsala universitet/Materialteori

    Author : Elis Uebel; Viktor Frilén; [2024]
    Keywords : Density functional theory; Dyson equation;

    Abstract : First-principle calculations is a key ingredient for us to understand, improve and design new materials. Density functional theory (DFT) [1] has proven to be a very powerful tool and a number of different versions exist depending on the problem at hand. READ MORE

  3. 2. Approach for frequency response-calibration for microphone arrays

    University essay from KTH/Hälsoinformatik och logistik

    Author : Jacob Drotz; [2023]
    Keywords : microphone array; frequency response; calibration; sine sweep; inverse filter; digital signal processing DSP ; convolution; Fast Fourier Transform FFT ; Discrete Fourier Transform DFT ; acoustic measurements; audio engineering; mikrofonarray; frekvenssvar; kalibrering; sinussvep; inverterat filter; digital signalbehandling; faltning; Fast Fourier Transform FFT ; Discrete Fourier Transform DFT ; akustiska mätningar; ljudteknik;

    Abstract : Matched frequency responses are a fundamental starting point for a variety ofimplementations for microphone arrays. In this report, two methods for frequencyresponse-calibration of a pre-assembled microphone array are presented andevaluated. READ MORE

  4. 3. A theoretical framework for interpretation and prediction of magneto-optical measurements

    University essay from Uppsala universitet/Materialteori

    Author : Viktor Frilén; [2023]
    Keywords : moke; tmoke; lmoke; pmoke; magneto-optical effects; layered media; dielectric function; maxwells equations; dielectric tensor; linear respons; magnetism; light induced transistions; DFT; SO;

    Abstract : The interplay of experiments and theory is essential to deepen our understanding of magnetization dynamics. This thesis aims to serve as a bridge between these two aspects by establishing a mathematical framework that enables the computation of optical observable quantities based on theoretical models. READ MORE

  5. 4. Development and Analysis of Small Signal DQ-Frame Model for Low Frequency Stability of Train Converters

    University essay from KTH/Skolan för elektroteknik och datavetenskap (EECS)

    Author : Fabian Tidner; [2023]
    Keywords : Low Frequency stability; DQ-frame modeling; Single phase converter; Electric rail way systems; Lågfrekvent stabilitet; DQ-ram modellering; Enfasig likriktare; Elektriska järnvägssystem;

    Abstract : In order to meet the increasing demand for sustainable transportation, trains need to run with tighter schedules, more departures and more trains in depot. Multiple trains in depot has been linked to low frequency instability at many locations around the world. READ MORE

  6. 5. First principles investigation of the thermal conductivity of Zr, ZrC, and ZrN

    University essay from KTH/Fysik

    Author : Daniel Karlsson; [2023]
    Keywords : Electron-phonon interaction; Density functional theory; Boltzmann transport equation; first-principles; thermal conductivity; electrical resistivity; Abinit; Phono3py; Elektron-fononväxelverkan; täthetsfunktionalteori; Boltzmanns transportekvation; värmeledningsförmåga; elektrisk resistivitet; Abinit; Phono3py;

    Abstract : The thermal conductivity and electrical resistivity of Zr, ZrC, and ZrN were calculated using first-principles density functional theory (DFT) and the Boltzmann transport equation. The electron-phonon scattering was modeled via the self-energy relaxation time approximation (SERTA), and the phonon-phonon scattering via the analogous single-mode relaxation time approximation (SMRTA). READ MORE