Search for dissertations about: "Order Reduction"

Showing result 1 - 5 of 1352 swedish dissertations containing the words Order Reduction.

2. 1. Model Order Reduction Based on Semidefinite Programming

   Author : Aivar Sootla; Institutionen för reglerteknik; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; model reduction; parameterized model reduction; nu-gap metric; semidefinite programming; frequency response matching.;

   Abstract : The main topic of this PhD thesis is complexity reduction of linear time-invariant models. The complexity in such systems is measured by the number of differential equations forming the dynamical system. This number is called the order of the system. READ MORE

4. 2. Investigations of the Kinetics of Reduction and Reduction/Carburization of NiO-WO3 Precursors

   Author : Hesham M. Ahmed; Seshadri Seetharaman; Ricardo Morales Estrella; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Reduction; Reduction-Carburization; Gas-solid Reactions; Kinetics; Hydrogen; Methane; Thermogravimetric analysis; Fluidized bed; Simulation; Thermal diffusivity; Thermal conductivity; Laser flash; Metallurgical process engineering; Metallurgisk processteknik; Process Metallurgy;

   Abstract : Kinetic studies of reduction of the mixtures of NiO and WO3 having different Ni/(Ni+W) molar ratios in flowing hydrogen gas were investigated by means of Thermo Gravimetric Analysis (TGA), Fluidized Bed (FB) technique as well as Thermal diffusivity measurements under isothermal conditions. In the case of TGA, the reaction progress was monitored by mass loss, while evolved gas analysis by a gas chromatograph was the indicator of the reaction progress in the case of FB. READ MORE

5. 3. Model Order Reduction with Rational Krylov Methods

   Author : K. Henrik A. Olsson; Axel Ruhe; Volker Mehrmann; KTH; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Model order reduction; dual rational Arnoldi; rational Krylov; moment matching; eigenvalue computation; stability analysis; heat exchanger model; Numerical analysis; Numerisk analys;

   Abstract : Rational Krylov methods for model order reduction are studied. A dual rational Arnoldi method for model order reduction and a rational Krylov method for model order reduction and eigenvalue computation have been implemented. It is shown how to deflate redundant or unwanted vectors and how to obtain moment matching. READ MORE

6. 4. Krylov Subspace Methods for Linear Systems, Eigenvalues and Model Order Reduction

   Author : Daniel Skoogh; Göteborgs universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; eigenvalues; eigenvectors; sparse; parallel; rational; Krylov; shift; invert; Arnoldi; linear systems; iterative; model; reduction; passive; 65F15; 65F50; 65Y05; 65F10; 93A30; 93B40; rational;

   Abstract : New variants of Krylov subspace methods for numerical solution of linear systems, eigenvalue, and model order reduction problems are described. A new method to solve linear systems of equations with several right-hand sides is described. READ MORE

7. 5. Reduction of Aerodynamic Forcing inTransonic Turbomachinery : Numerical Studies on Forcing Reduction Techniques

   Author : Florian Fruth; Torsten Fransson; Damian Vogt; Ronald Mailach; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Forced Response; Aerodynamic Forcing; Efficiency; Blade Count Ratio; Clocking;

   Abstract : Due to more and more aggressive designs in turbomachinery, assuring the structural integrity of its components has become challenging. Also influenced by this trend is blade design, where lighter and slimmer blades, in combination with higher loading, lead to an increased risk of failure, e.g. in the form of blade vibration. READ MORE