Sökning: "differential algebraic equations"

Visar resultat 1 - 5 av 56 avhandlingar innehållade orden differential algebraic equations.

1. 1. Structural algorithms and perturbations in differential-algebraic equations

   Författare :Henrik Tidefelt; Torkel Glad; Mats Jirstrand; Linköpings universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; differential-algebraic equations; index reduction; singular perturbation; Automatic control; Reglerteknik;

   Sammanfattning : Den kvasilinjära formen av differential-algebraiska ekvationer är både en mycket allmängiltig generalisering av den linjära tidsinvarianta formen, och en form som visar sig lämpa sig väl för indexreduktionsmetoder som vi hoppas ska komma att bli både praktiskt tillämpbara och väl förstådda i framtiden.Kuperingsalgoritmen (engelska: the shuffle algorithm) användes ursprungligen för att bestämma konsistenta initialvillkor för linjära tidsinvarianta differential-algebraiska ekvationer, men har även andra tillämpningar, till exempel det grundläggande problemet numerisk integration. LÄS MER

3. 2. 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

4. 3. Identification and Estimation for Models Described by Differential-Algebraic Equations

   Författare :Markus Gerdin; Torkel Glad; Lennart Ljung; Manfred Deistler; Linköpings universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Differential-Algebraic Equations; Identifiability; Nonlinear systems; Modelling; Identification; Descriptor systems; Automatic control; Reglerteknik;

   Sammanfattning : Differential-algebraic equations (DAEs) form the natural way in which models of physical systems are delivered from an object-oriented modeling tool like Modelica. Differential-algebraic equations are also known as descriptor systems, singular systems, and implicit systems. LÄS MER

5. 4. Topics in analytic theory of partial differential equations

   Författare :Sergei Chulkov; Jan-Erik Björk; Mattias Jonsson; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; partial differential equations; Algebra; geometry and mathematical analysis; Algebra; geometri och analys;

   Sammanfattning : The thesis consists of three papers I, II III devoted to some topics in analytic theory of partial differential equations. The main paper is II. In this paper we study a version of the classical problem on the convergence of formal solutions of systems of partial differential equations. LÄS MER

7. 5. Runge-Kutta Solution of Initial Value Problems: Methods, Algorithms and Implementation

   Författare :Hans Olsson; Institutionen för datavetenskap; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Computer science; stiffness; software; computational process; differential algebraic equations; ordinary differential equations; Runge-Kutta; initial value problems; time-stepping; system; kontroll; numerisk analys; Datalogi; control; numerical analysis; systems;

   Sammanfattning : The last decades have seen a strongly increasing use of computers for modeling larger and more complex systems. This has been made possible by a combination of increasing computer power and easy-to-use graphical modeling environments and libraries of components. LÄS MER