Search for dissertations about: "Transport operator"

Showing result 21 - 25 of 40 swedish dissertations containing the words Transport operator.

2. 21. Homogenization of pseudoparabolic reaction-diffusion-mechanics systems : Multiscale modeling, well-posedness and convergence rates

   Author : Arthur J. Vromans; Adrian Muntean; Claudia Timofte; Karlstads universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Reaction-diffusion-mechanics system; parameter delimitation; parabolic-pseudoparabolic equations; weak solvability; Rothe method; periodic homogenization; corrector estimates; vanishing thin domains; Matematik; Mathematics;

   Abstract : In this dissertation, parabolic-pseudoparabolic equations are proposed to couple chemical reactions, diffusion, flow and mechanics in heterogeneous materials using the framework of mixture theory. The weak solvability is obtained in a one dimensional setting for the full system posed in a homogeneous domain - a formulation which we have obtained using the classical mixture theory. READ MORE

4. 22. Towards semi-automation of forestry cranes : automated trajectory planning and active vibration damping

   Author : Szabolcs Fodor; Leonid Freidovich; Carlos Vázquez; Anton Shiriaev; Torben Ole Andersen; Umeå universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Forestry; forwarder cranes; semi-automation; slewing actuator; automated trajectory planning; oscillations; inner boom actuator; active vibration damping; frequency estimation; input shaping control technique; H2-optimal control;

   Abstract : Forests represent one of the biggest terrestrial ecosystems of Earth, that can produce important raw renewable materials such as wood with the help of sun, air and water. To efficiently extract these raw materials, the tree harvesting process is highly mechanized in developed countries, meaning that advanced forestry machines are continuously used to fell, to process and to transport the logs and biomass obtained from the forests. READ MORE

5. 23. The Missing link : Business Models Lock-in in Sociotechnical Transitions

   Author : Rami Darwish; Mats Engwall; Vinit Parida; KTH; []
   Keywords : Business Models; Sociotechnical Transitions; Lock-in; Resource Dependence; Industriell ekonomi och organisation; Industrial Economics and Management;

   Abstract : Societal and environmental challenges present challenges for our current industrial systems. In order to respond to these difficulties, various alternative systems have been suggested, as they promise sustainability and increased societal quality of life enabled by innovative technologies. READ MORE

6. 24. On Monte Carlo Operators for Studying Collisional Relaxation in Toroidal Plasmas

   Author : Qaisar Mukhtar; Torbjörn Hellsten; Tainia Kurki-Suonio; KTH; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Fusion plasma; thermonuclear fusion; tokamak; Coulomb collisions; stochastic differential equations with singular diffusion coefficients; Monte Carlo schemes; spatial diffusion; modelling; Fokker-Planck equation; RF-heating.;

   Abstract : This thesis concerns modelling of Coulomb collisions in toroidal plasma with Monte Carlo operators, which is important for many applications such as heating, current drive and collisional transport in fusion plasmas. Collisions relax the distribution functions towards local isotropic ones and transfer power to the background species when they are perturbed e. READ MORE

7. 25. Photonic devices with MQW active material and waveguide gratings : modelling and characterisation

   Author : Nadeem Akram; Lars Thylén; Hartmut Hillmer; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Method of Lines; Grating; ARROW Waveguide; Semiconductor laser; quantum well; Photonics; Fotonik;

   Abstract : The research work presented in this thesis deals with modelling, design and characterisation of passive and active optical waveguide devices. The rst part of the thesis is related to algorithm development and numerical modelling of planar optical waveguides and gratings using the Method of Lines (MoL). READ MORE