Search for dissertations about: "Model order reduction"

Showing result 6 - 10 of 530 swedish dissertations containing the words Model order reduction.

2. 6. Model Reduction for Linear Time-Varying Systems

   Author : Henrik Sandberg; Anders Rantzer; Sanjay Lall; Institutionen för reglerteknik; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Automation; robotics; control engineering; Performance limitations; Convergence analysis; Frequency-domain analysis; Error bounds; Time-varying systems; Model reduction; Linear systems; Automatiska system; robotteknik; reglerteknik; Model reduction;

   Abstract : The thesis treats model reduction for linear time-varying systems. Time-varying models appear in many fields, including power systems, chemical engineering, aeronautics, and computational science. They can also be used for approximation of time-invariant nonlinear models. Model reduction is a topic that deals with simplification of complex models. READ MORE

4. 7. Investigating the parameters that influence the behaviour of natural iron ores during the iron production process

   Author : Abraham Judah Bumalirivu Muwanguzi; Andrey V Karasev; Henrik Saxèn; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; natural iron ore; iron production; characterization; physical and metallurgical properties; sinter; pellet; direct reduction; low temperature degradation; sample weight; sample positioning; microstructure; reduction degree; solid conversion; Volumetric Model; Grain Model; Random Pore Model; Muko; Uganda;

   Abstract : In the iron production processes, sinters and pellets are mostly used as raw materials due to their consistency with respect to physical and chemical properties. However, natural iron ores, as mined, are rarely used directly as a feed material for iron processing. READ MORE

5. 8. 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

6. 9. Calibration and Reduction of Large-Scale Dynamic Models - Application to Wind Turbine Blades

   Author : Majid Khorsand Vakilzadeh; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; maximum likelihood estimator; model reduction; finite element model calibration; Bayesian model calibration; Verification and validation; wind turbine blade; logarithmic least square estimator; large-scale dynamics model; SWPTC;

   Abstract : This thesis investigates the validity of structural dynamics models of wind turbine blades. An outlook on methods for model calibration to make models valid for their intended use is presented in the thesis. The intention is to make the models valid for robust predictions. The model validity is here assessed to be of hierarchical dual level. READ MORE

7. 10. Model Reduction and Parameter Estimation for Diffusion Systems

   Author : Bharath Bhikkaji; Torsten Söderström; Claes Breitholtz; Uppsala universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Diffusion system; Partial differential equations PDEs ; Model reduction; PDE solvers; Finite difference approximation; Chebyshev polynomials; System identification; Parameter estimation; Recursive estimation; Frequency domain estimation; Signal processing; Signalbehandling;

   Abstract : Diffusion is a phenomenon in which particles move from regions of higher density to regions of lower density. Many physical systems, in fields as diverse as plant biology and finance, are known to involve diffusion phenomena. Typically, diffusion systems are modeled by partial differential equations (PDEs), which include certain parameters. READ MORE