Search for dissertations about: "Stochastic modelling"

Showing result 16 - 20 of 173 swedish dissertations containing the words Stochastic modelling.

  2. 16. Element transport in aquatic ecosystems – Modelling general and element-specific mechanisms

    Author : Lena Konovalenko; Clare Bradshaw; Ulrik Kautsky; Linda Kumblad; Dan Baird; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; radionuclides; elements; concentration ratio; bioaccumulation; biomagnification; fish; modelling; aquatic food web; ecosystem; Cs; Sr; environmental risk assessment; marin ekotoxikologi; Marine Ecotoxicology;

    Abstract : Radionuclides are widely used in energy production and medical, military and industrial applications. Thus, understanding the behaviour of radionuclides which have been or may be released into ecosystems is important for human and environmental risk assessment. READ MORE

  4. 17. Stochastic Modelling and Reconstruction of Random Shapes

    Author : Finn Lindgren; Matematisk statistik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; operations research; Statistics; operationsanalys; Statistik; programmering; aktuariematematik; actuarial mathematics; programming;

    Abstract : This thesis originates from the problem of reconstructing the three-dimensional shape of objects, when the only available data are two-dimensional images. The solution presented is based on stochastic models for random object shapes and measurements, in combination with practical surface representation and simulation methods. READ MORE

  5. 18. Element transport in marine coastal ecosystems – modelling general and element-specific mechanisms

    Author : Lena Konovalenko; Clare Bradshaw; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Modelling; bioaccumulation; concentration ratio; radionuclides; marine foodweb.; Marine Ecology; marin ekologi;

    Abstract : Understanding the behaviour of naturally-occurring and anthropogenically-derived radionuclides (isotopes) in the marine environment is important, because there is a need for their effective utilization either as in situ tracers or for industry, medical applications, the planning of waste-disposal facilities, and estimations of human and animal health risks. Radionuclides generally have the same chemical properties as their stable element analogues and thus show similar environmental behaviour and cycling to their stable counterparts. READ MORE

  6. 19. Anisotropy-resolving subgrid-scale modelling using explicit algebraic closures for large eddy simulation

    Author : Amin Rasam; Arne Johansson; Bernard Geurts; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Turbulence; large eddy simulation; explicit algebraic subgridscale model; passive scalar; stochastic modelling; periodic hill flow; Engineering Mechanics; Teknisk mekanik;

    Abstract : The present thesis deals with the development and performance analysis ofanisotropy-resolving models for the small, unresolved scales (”sub-grid scales”,SGS) in large eddy simulation (LES). The models are characterised by a descriptionof anisotropy by use of explicit algebraic models for both the subgridscale(SGS) stress tensor (EASSM) and SGS scalar flux vector (EASSFM). READ MORE

  7. 20. Experimental and Modelling Studies on the Spreading of Non-Aqueous Phase Liquids in Heterogeneous Media

    Author : Fritjof Fagerlund; Auli Niemi; Tissa Illangasekare; Karsten Jensen; Uppsala universitet; []
    Keywords : Hydrology; NAPL; Multi-phase flow; Modelling; Experiment design; Heterogeneity; Constitutive relations; Multi-constituent contaminants; Capillary pressure; Relative permeability; Hysteresis; Hydrologi;

    Abstract : Non-Aqueous Phase Liquids (NAPLs) include commonly occurring organic contaminants such as gasoline, diesel fuel and chlorinated solvents. When released to subsurface environments their spreading is a complex process of multi-component, multi-phase flow. READ MORE