Sökning: "Analytical Green’s function"

Visar resultat 1 - 5 av 10 avhandlingar innehållade orden Analytical Green’s function.

1. 1. Analytical and Numerical Developments in Strongly Correlated Systems: Perspectives from TDDFT and Green's Functions

   Författare :Daniel Karlsson; Matematisk fysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Many-Body Perturbation Theory; Hubbard model; TDDFT; Green s function; DFT; Quantum Transport; Disorder; Fysicumarkivet A:2014:Karlsson;

   Sammanfattning : This thesis investigates different methods for treating strongly correlated systems, and discusses their respective strengths and weaknesses. Many of the results presented in this thesis come from comparing the different methods and approximations to exact results. LÄS MER

3. 2. Power Reactor Noise Studies and Applications

   Författare :Vasiliy Arzhanov; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; power spectra; control rod vibrations; Green s function; nesting hypothesis; adjoint function; fluctuating boundary; noise diagnostics; Accelerator Driven System; localisation algorithm; point reactor and adiabatic approximation;

   Sammanfattning : The present thesis deals with the neutron noise arising in power reactor systems. Generally, it can be divided into two major parts: first, neutron noise diagnostics, or more specifically, novel methods and algorithms to monitor nuclear industrial reactors; and second, contributions to neutron noise theory as applied to power reactor systems. LÄS MER

4. 3. The Effect of Different Perturbations on the Stability Analysis of Light Water Reactors

   Författare :Victor Dykin; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; BWR and PWR stability; stability indicators; propagating density perturbation; autocorrelation function; density wave oscillations; decay ratio; non-white driving force; damped harmonic oscillator; reduced order models; Green s function technique;

   Sammanfattning : Neutron noise analysis techniques are studied and developed, with primary useof determining the stability of Boiling Water Reactors (BWRs). In particular, the role ofa specific perturbation prevailing in Light Water Reactors, the propagating densityperturbation, in the stability of BWRs and on the noise field of LWRs in general, isinvestigated by considering three topics. LÄS MER

5. 4. Mesoscopic superconductivity : quasiclassical approach

   Författare :Marek Ožana; Andrei Shelankov; Dierk Rainer; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; mesoscopic superconductivity; quasiclassical theory; boundary conditions; multi-layer structures; Gor kov equations; quasiclassical Green s function; Green s function on classical trajectories;

   Sammanfattning : This Thesis is concerned with the quasiclassical theory of meso-scopic superconductivity. The aim of the Thesis is to introduce the boundary conditions for a quasiclassical Green’s function on partially transparent interfaces in mesoscopic superconducting structures and to analyze the range of applicability of the quasiclassical theory. LÄS MER

7. 5. Noise Applications in Light Water Reactors with Traveling Perturbations

   Författare :Victor Dykin; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Green s function technique; transit times; decay ratio; cross-correlation function; void fraction; global and regional instabilities; propagating density perturbation; BWR stability; reduced order models; non-white driving force; local component; Monte Carlo; space-dependent neutron noise; density wave oscillations;

   Sammanfattning : Neutron noise induced by perturbations traveling with the coolant of light water reactors (LWRs) is investigated. Different methods to simulate the effect of propagating perturbations are considered. The studies are performed in both open- and closed-loop systems and summarized in three chapters. LÄS MER