Sökning: "stability analysis"

Visar resultat 6 - 10 av 1316 avhandlingar innehållade orden stability analysis.

  1. 6. Block stability analysis using deterministic and probabilistic methods

    Författare :Mehdi Bagheri; Håkan Stille; Charlie C. Li; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Block stability analysis; Model uncertainty; Joint relaxation; Partial factor; Sensitivity analysis;

    Sammanfattning : This thesis presents a discussion of design tools for analysing block stability around a tunnel. First, it was determined that joint length and field stress have a significant influence on estimating block stability. LÄS MER

  3. 7. Control and Analysis of Pulse-Modulated Systems

    Författare :Stefan Almér; Ulf Jönsson; Gilead Tadmor; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Pulse-width modulation; Periodic systems; Stability analysis; Harmonic analysis; Lyapunov methods; Dynamic phasors; Harmonic transfer function; Switched mode power converters; Sampled data modeling; H-infinity synthesis; Optimization; systems theory; Optimeringslära; systemteori;

    Sammanfattning : The thesis consists of an introduction and four appended papers. In the introduction we give an overview of pulse-modulated systems and provide a few examples of such systems. Furthermore, we introduce the so-called dynamic phasor model which is used as a basis for analysis in two of the appended papers. LÄS MER

  4. 8. Global stability analysis of three-dimensional boundary layer flows

    Författare :Mattias Brynjell-Rahkola; Dan Henningson; Philipp Schlatter; Ardeshir Hanifi; Spencer Sherwin; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Hydrodynamic stability; transition to turbulence; global analysis; boundary layers; roughness; laminar flow control; Stokes Laplace preconditioner; optimal forcing; crossflow vortices; Ginzburg-Landau; Falkner-Skan-Cooke; Blasius; lid-driven cavity;

    Sammanfattning : This thesis considers the stability and transition of incompressible boundary layers. In particular, the Falkner–Skan–Cooke boundary layer subject to a cylindrical surface roughness, and the Blasius boundary layer with applied localized suction are investigated. LÄS MER

  5. 9. Motion Analysis and Postural Stability of Transtibial Prosthesis Users

    Författare :David Rusaw; Göteborgs universitet; []
    Nyckelord :Artificial limb; balance; electromyography EMG ; motion analysis; postural stability;

    Sammanfattning : The AIMS of the thesis were to critically evaluate motion analysis methods used during investigations of transtibial prosthesis users, and to propose improvements to these methods. Additionally, the aim was to evaluate if vibratory feedback could be used to improve postural stability in transtibial prosthesis users and how being a prosthesis user influenced muscular response to postural perturbations. LÄS MER

  7. 10. Approximating Stochastic Partial Differential Equations with Finite Elements: Computation and Analysis

    Författare :Andreas Petersson; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Lévy process; Lyapunov equation; white noise; finite element method; multilevel Monte Carlo; Monte Carlo; multiplicative noise; asymptotic mean square stability; stochastic heat equation; covariance operator; weak convergence; generalized Wiener process; numerical approximation; stochastic wave equation; Stochastic partial differential equations;

    Sammanfattning : Stochastic partial differential equations (SPDE) must be approximated in space and time to allow for the simulation of their solutions. In this thesis fully discrete approximations of such equations are considered, with an emphasis on finite element methods combined with rational semigroup approximations. LÄS MER