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Biodiversity in Agricultural Landscapes: Landscape and Scale-Dependent Effects of Organic Farming

Popular Abstract in Swedish Brukandet av jordbrukslandskapet har förändrats dramatisk under det senaste århundradet. Det tidigare mosaikartade landskapet, med en blandning av små åkrar, ängar, hagar och våtmarker, har idag i många områden ersatts av ett likformigt landskap som domineras av vidsträckta åkrar. Samtidigt har användandet av konstgödsel och kemiska bekämpningsmedel ökat. Tillsammans meDeclines in the distribution and abundance of many farmland species during recent decades have been attributed to agricultural intensification. Agri-environment schemes are commonly used in Europe to reduce this loss of farmland biodiversity, but their effectiveness may depend on several external factors. In this thesis, I have used one such scheme, organic faming, as a landscape scale experiment

Large Eddy Simulation of a turbulent flow past a pair of symmetric backward-facing steps: A sensitivity analysis

Large Eddy Simulation is used to study the flow behind a pair of symmetric backward facing steps. As reported in the literature, the flow exhibits an asymmetric pattern characterized by the deflection of the jet toward of the walls. The LES results are compared to LDA measurements showing the ability of the present numerical tool to capture the complex features of the flow. Furthermore, a sensitiv

NMR Diffusion Studies in Heterogeneous Systems. Surfactant solutions, Polymer solutions and Gels

The aim of this study has been to investigate the self-diffusion behaviour in polymer solutions and in surfactant solutions using the pulsed field gradient (PFG) NMR technique. The NMR self-diffusion experiment was shown to provide detailed information in complex surfactant mixtures. In particular, the microemulsion phase and the hexagonal phase of Didodecyldimethylammoniumsulphate (DDAS) formed

Beyond von Neumann: weakly programmable processor arrays and their programming

The age of parallelism is here. For a sustainable software development for massively parallel architectures the von Neumann model need to be replaced by one with native support for parallelism. We suggest a data flow model for signal processing applications. This will make it possible to reuse software implementations for different targets and future platform generations. We also outline our devel

Comparison of Ray Tracing and Channel-Sounder Measurements for Vehicular Communications

This paper presents the results of an accuracy study of a deterministic channel model for vehicle-to-vehicle (V2V) communications. Channel simulations obtained from the ray-tracing model developed by TU Braunschweig are compared to data gathered during the DRIVEWAY V2V channel measurement campaign at 5.6 GHz in the city of Lund in summer 2009. The analysis focuses on PDP and channel gains in an ur