Sökning: "perturbation analysis"

Visar resultat 1 - 5 av 141 avhandlingar innehållade orden perturbation analysis.

  1. 1. Global stability analysis of complex fluids

    Författare :Iman Lashgari; Luca Brandt; Francois Gallaire; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; non-Newtonian flow; Carreau model; Oldroyd-B model; FENE-P model; modal analysis; nonmodal analysis; sensitivity analysis;

    Sammanfattning : The main focus of this work is on the non-Newtonian effects on the inertial instabilities in shear flows. Both inelastic (Carreau) and elastic models (Oldroyd-B and FENE-P) have been employed to examine the main features of the non-Newtonian fluids; shear-thinning, shear-thickening and elasticity. LÄS MER

  3. 2. Topics in perturbation theory : From IBP identities to integrands

    Författare :Alessandro Georgoudis; Joseph A. Minahan; Tristan McLoughlin; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Perturbation theory; Feynman Integrals; Integrable field theories; Correlation functions.; Theoretical Physics; Teoretisk fysik;

    Sammanfattning : In this thesis we present different topics in perturbation theory. We start by introducing the method of integration by parts identities, which reduces a generic Feynman integral to a linear combination of a finite basis of master integrals. LÄS MER

  4. 3. Railway operation analysis : Evaluation of quality, infrastructure and timetable on single and double-track lines with analytical models and simulation

    Författare :Olov Lindfeldt; Bo-Lennart Nelldal; Lars-Göran Mattsson; Ingo Hansen; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Railway operation; Railway capacity; Single-track; Double-track; Partial double-track; Inter-station distance; Delay; Delay propagation; Crossing; Overtaking; Timetable flexibility; Simulation; Experimental design; Civil engineering and architecture; Samhällsbyggnadsteknik och arkitektur;

    Sammanfattning : This thesis shows the advantages of simple models for analysis of railway operation. It presents two tools for infrastructure and timetable planning. It shows how the infrastructure can be analysed through fictive line designs, how the timetable can be treated as a variable and how delays can be used as performance measures. LÄS MER

  5. 4. Community Robustness Analysis : Theoretical Approaches to Identifying Keystone Structures in Ecological Communities

    Författare :Sofia Berg; Tomas Jonsson; Bo Ebenman; Daniel Stouffer; Linköpings universitet; []
    Nyckelord :;

    Sammanfattning : Most of the world’s ecosystems suffer from stress caused by human activities such as habitat destruction, fragmentation, overexploitation of species and climate change. These factors affect the reproduction and/or survival of individual species as well as interactions between species in ecological communities. LÄS MER

  7. 5. Switched Bond Graphs : Simulation and Analysis

    Författare :Krister Edström; Linköpings universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Bond graphs; Hybrid systems; Modeling; Simulation; Causality; Discontinuities;

    Sammanfattning : In this thesis an approach to modeling and simulation of mode switching systems is investigated. This approach, switched bond graphs, is an extension of the bond graph language in the sense that it allows modeling of mode switching phenomena.The classical bond graph language as well as the switched bond graph language are presented. LÄS MER