Sökning: "variable time-step"

Visar resultat 1 - 5 av 7 avhandlingar innehållade orden variable time-step.

  1. 1. Adaptive Geometric Numerical Integration of Mechanical Systems

    Författare :Klas Modin; Matematik LTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; multibody dynamics; Geometric numerical integration; rolling bearing simulation; adaptive time-stepping; variable time-step;

    Sammanfattning : This thesis is about structure preserving numerical integration of initial value problems, i.e., so called geometric numerical integrators. LÄS MER

  3. 2. Wind Turbine Models for Power System Stability Studies

    Författare :Abram Perdana; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; fixed-speed; variable-speed; validation; modelling; power system stability; frequency stability; aggregated model; wind turbine; voltage stability;

    Sammanfattning : The purpose of this thesis is to develop dynamic models of wind turbines for power system stability studies. More specifically, the wind turbine models are mainly intended for voltage and frequency stability studies. LÄS MER

  4. 3. Dynamic Models of Wind Turbines

    Författare :Abram Perdana; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; frequency stability; variable-speed; modeling; power system stability; validation; aggregated model; fixed-speed; voltage stability; wind turbine;

    Sammanfattning : The impact of wind power generation in the power system is no longer negligible. Therefore, there is an urgent need for wind turbine models that are capable of accurately simulating the interaction between wind turbines or wind farms and the power system. LÄS MER

  5. 4. Static Visualizations for Dynamic Hierarchies

    Författare :Wiebke Köpp; Tino Weinkauf; Vijay Natarajan; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Dynamic hierarchies; Static visualization; Pixel-based visualization; Scalar data; Topology; Layout stability; Dynamiska hierarkier; Statisk visualisering; Pixelbaserad visualisering; Skalärdata; Topologi; Layout-stabilitet; Datalogi; Computer Science;

    Sammanfattning : Dynamic hierarchical data describes phenomena in a wide range of domains, from file management to demographics and business administration, as well as feature extraction results in spatial scientific data. As with all data, visualization is an integral step for gaining understanding about dynamic hierarchical data. LÄS MER

  7. 5. Fast Adaptive Numerical Methods for High Frequency Waves and Interface Tracking

    Författare :Jelena Popovic; Olof Runborg; Hongkai Zhao; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; high frequency waves; Helmholtz equation; interface tracking; time-space adaptivity; multiresolution; Hamilton-Jacobi;

    Sammanfattning : The main focus of this thesis is on fast numerical methods, where adaptivity is an important mechanism to lowering the methods' complexity. The application of the methods are in the areas of wireless communication, antenna design, radar signature computation, noise prediction, medical ultrasonography, crystal growth, flame propagation, wave propagation, seismology, geometrical optics and image processing. LÄS MER