Sökning: "Differential algebraic equation"

Visar resultat 1 - 5 av 31 avhandlingar innehållade orden Differential algebraic equation.

  1. 1. Differential-algebraic equations and matrix-valued singular perturbation

    Författare :Henrik Tidefelt; Torkel Glad; Ulf Jönsson; Linköpings universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Differential-algebraic equations; uncertainty; singular perturbation; state estimation; Automatic control; Reglerteknik;

    Sammanfattning : With the arrival of modern component-based modeling tools for dynamic systems, the differential-algebraic equation form is increasing in popularity as it is general enough to handle the resulting models. However, if uncertainty is allowed in the equations — no matter how small — this thesis stresses that such equations generally become ill-posed. LÄS MER

  2. 2. Numerical Computations with Fundamental Solutions

    Författare :Per Sundqvist; Henrik Brandén; Sverker Holmgren; Alison Ramage; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; fundamental solution; partial differential equation; partial difference equation; iterative method; preconditioner; boundary method; Numerical Analysis; Numerisk analys;

    Sammanfattning : Two solution strategies for large, sparse, and structured algebraic systems of equations are considered. The first strategy is to construct efficient preconditioners for iterative solvers. The second is to reduce the sparse algebraic system to a smaller, dense system of equations, which are called the boundary summation equations. LÄS MER

  3. 3. On computational methods for nonlinear estimation

    Författare :Thomas Schön; Linköpings universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Nonlinear estimation; Particle filter; Kalman filter; System identification; Convex optimization; Differential-algebraic equation; TECHNOLOGY; TEKNIKVETENSKAP;

    Sammanfattning : The Bayesian approach provides a rather powerful framework for handling nonlinear, as well as linear, estimation problems. We can in fact pose a general solution to the nonlinear estimation problem. However, in the general case there does not exist any closed-form solution and we are forced to use approximate techniques. LÄS MER

  4. 4. Topics in projective algebraic optimization

    Författare :Lukas Gustafsson; Sandra Di Rocco; Kathlén Kohn; Cordian Riener; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : This thesis explores optimization challenges within algebraic statistics, employing both topological and geometrical methodologies to derive new insights. The main focus is the optimization degree of nearest point and Gaussian maximum likelihood estimation problems with algebraic constraints. LÄS MER

  5. 5. PDEModelica – A High-Level Language for Modeling with Partial Differential Equations

    Författare :Levon Saldamli; Peter Fritzson; Bernhard Bachmann; Francesco di Casella; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; mathematical modeling; PDEModelica; Modelica; object-oriented modeling; equation-based modeling; declarative modeling; high-level modeling languages; mathematical modeling languages; Computer science; Datavetenskap;

    Sammanfattning : This thesis describes work on a new high-level mathematical modeling language and framework called PDEModelica for modeling with partial differential equations. It is an extension to the current Modelica modeling language for object-oriented, equation-based modeling based on differential and algebraic equations. LÄS MER