Sökning: "stability criteria"

Visar resultat 1 - 5 av 90 avhandlingar innehållade orden stability criteria.

  1. 1. Wellbore stability analysis based on a new true-triaxial failure criterion

    Författare :Adel Al-Ajmi; Robert Zimmerman; Bernt Aadnoy; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; failure criteria; Mogi failure criterion; intermediate principal stress; polyaxial test data; wellbore stability; Geoengineering and mining engineering; Geoteknik och gruvteknik;

    Sammanfattning : A main aspect of wellbore stability analysis is the selection of an appropriate rock failure criterion. The most commonly used criterion for brittle failure of rocks is the Mohr-Coulomb criterion. LÄS MER

  3. 2. Stability of tailings dams : focus on water cover closure

    Författare :Annika Bjelkevik; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Soil Mechanics; Geoteknik;

    Sammanfattning : Mining activities have been ongoing for thousands of years within Sweden. As the results of previous activities are evident today, i.e. for example acid mine drainage (AMD), the focus and interest on closure and remediation of mine sites and tailings storage facilities (TSFs) has increased. LÄS MER

  4. 3. Input-Output Stability Analysis of Networked Control Systems

    Författare :Johannes Nygren; Kristiaan Pelckmans; Torkel Glad; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Networked control systems; L2-stability; quantization; delay; packet dropouts; switching systems; Elektroteknik med inriktning mot reglerteknik; Electrical Engineering with specialization in Automatic Control;

    Sammanfattning : The main focus of the thesis is to derive stability criteria for networked control system (NCS) models featuring imperfections such as time-varying and constant delays, quantization, packet dropouts, and non-uniform sampling intervals. The main method of proof is based on matrix algebra, as opposed to methods using Lyapunov functions or integral quadratic constraints (IQC). LÄS MER

  5. 4. Voltage Stability Simulations Using Detailed Models Based on Field Measurements

    Författare :Daniel Karlsson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; capacity limits; field measurements; dynamic load models; on-load tap-changer control system; voltage stability; simulations;

    Sammanfattning : This dissertation deals with voltage stability simulations, including dynamic load models, on-load tap-changer control system dynamics and generator reactive power output capacity limits. The simulations are based on sequential solving of ordinary load flow cases augmented with dynamic models. LÄS MER

  7. 5. Analytic Parameterization of Stabilizing Controllers for the Moore-Greitzer Compressor Model

    Författare :Alina Andersson; Institutionen för reglerteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Nonlinear control; Moore-Greitzer compressor model; Dynamic output feedback; Compressors; Nonlinear control systems; Stability robustness; Constraints; Nonlinearity; Lyapunov stability;

    Sammanfattning : This work presents an extension, simplification and application of a design procedure for dynamic output feedback design for systems with nonlinearities satisfying quadratic constraints (QC). Our method was motivated by the challenges of output feedback control design for the three-state Moore-Greitzer (MG) compressor model. LÄS MER