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Showing result 1 - 5 of 47 swedish dissertations matching the above criteria.

  2. 1. Mathematical analysis and approximation of a multiscale elliptic-parabolic system

    Author : Omar Richardson; Adrian Muntean; Alfred Schmidt; Karlstads universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Two-scale modelling; two-scale Galerkin approximation; inverse Robin estimates; elliptic-parabolic system; a priori analysis; a posteriori error estimators; Matematik; Mathematics;

    Abstract : We study a two-scale coupled system consisting of a macroscopic elliptic equation and a microscopic parabolic equation. This system models the interplay between a gas and liquid close to equilibrium within a porous medium with distributed microstructures. We use formal homogenization arguments to derive the target system. READ MORE

  4. 2. Asymptotic analysis of solutions to elliptic and parabolic problems

    Author : Peter Rand; Vladimir Kozlov; Mikael Langer; Vitali Liskevich; Linköpings universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Asymptotic behaviour; The Emden-Fowler equation; Parabolic system; Spectral splitting; Cylinder; Perturbation; MATHEMATICS; MATEMATIK;

    Abstract : In the thesis we consider two types of problems. In Paper 1, we studysmall solutions to a time-independent nonlinear elliptic partial differential equation of Emden-Fowler type in a semi-infnite cylinder. The asymptotic behaviour of these solutions at infnity is determined. First, the equation under the Neumann boundary condition is studied. READ MORE

  5. 3. A pseudoparabolic reaction-diffusion-mechanics system : Modeling, analysis and simulation

    Author : Arthur Vromans; Adrian Muntean; Martin Lind; Mohammad Asadzadeh; Karlstads universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; reaction-diffusion-mechanics model; parameter delimitation; parabolic-pseudoparabolic equations; weak solvability; Rothe method; periodic homogenization; Matematik; Mathematics;

    Abstract : In this thesis, parabolic-pseudoparabolic equations are derived coupling chemical reactions, diffusion, flow and mechanics in a heterogeneous medium using the framework of mixture theory. The weak solvability in 1-D of the obtained models is studied. READ MORE

  6. 4. Qualitative Aspects of Nonlinear Parabolic Partial Differential Equations and Systems

    Author : Joakim Petersson; Matematik (naturvetenskapliga fakulteten); []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Matematik; Mathematics; Optimal constants; Global existence; Parabolic equations; Quenching;

    Abstract : This thesis contains four papers about some aspects of nonlinear parabolic equations and systems. Paper 1. A note on quenching for parabolic equations with dynamic boundary conditions We present a quenching result for semilinear parabolic equations with dynamic boundary conditions in bounded domains with a smooth boundary. Paper 2. READ MORE

  7. 5. Optical Efficiency of Low-Concentrating Solar Energy Systems with Parabolic Reflectors

    Author : Maria Brogren; Arne Roos; Björn Karlsson; Andreas Häberle; Uppsala universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Engineering physics; Photovoltaic cells; Photovoltaic-thermal systems; Parabolic reflectors; Optical properties; Reflector materials; Optical efficiency; Accelerated ageing; Outdoor ageing; Building-integrated photovoltaics; Teknisk fysik; Engineering physics; Teknisk fysik;

    Abstract : Solar electricity is a promising energy technology for the future, and by using reflectors for concentrating solar radiation onto photovoltaic cells, the cost per produced kWh can be significantly reduced. The optical efficiency of a concentrating system determines the fraction of the incident energy that is transferred to the cells and depends on the optical properties of the system components. READ MORE