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Ultra-wideband (UWB) communication is a potential technique for future high-speed networks. In this paper, we investigate low complexity signal detection approaches for OFDM based UWB systems. In particular, we develop practical approaches for channel estimation and interference suppression. Computer simulation results show that these techniques can be effectively used in OFDM based UWB systems fo

Popular Abstract in Swedish Vilken typ av mat vi konsumerar och hur den produceras har stor inverkan på vår miljö och hälsa. Den globala livsmedelsproduktionen ockuperar drygt en tredjedel av världens markyta, står för runt 30 % av den totala klimatpåverkan och är identifierad som ett av de största hoten mot vår miljö. Vi lever också i en värld där nästan en miljard människor går hungriga och ännuFood production and consumption are key drivers of environmental pressures and essential factors in the promotion and maintenance of health. Production of food occupies more than 1/3 of global land areas and is estimated to be responsible for some 30% of global greenhouse gas emissions. At the same time, we live in a world where nearly one billion people go hungry and even more people suffer from

Throughout this thesis, samples of various materials with applications in energy converting devices have been prepared by focused ion beam machining and investigated by transmission electron microscopy. Energy converting devices can be solar cells or light emitting diodes, which turn light into electricity or vice versa. They can also be fuel cells or electrolyzer cells, which turn chemical energy

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The concentrations of sulfur and several more elements were measured in a network of six sites in southern Sweden. High time resolution samples were taken using a continuous filter sampler and analysed by particle induced X-ray emission (PIXE). Simultaneous increases in the sulfur concentrations were seen along the network due to the inflow of polluted air masses. High sulfur concentrations genera

Approaches to determining the factuality of diagnoses and findings in clinical text tend to rely on dictionaries of marker words for uncertainty and negation. Here, a method for semi-automatically expanding a dictionary of marker words using distributional semantics is presented and evaluated. It is shown that ranking candidates for inclusion according to their proximity to cluster centroids of se

Today’s multimedia systems use different types of media with different play-out devices. Currently we are heading towards a situation where for example cellular content providers, the home entertainment industry and networked multimedia over the Internet provide different content and dirferent formats that are incompatible with devices from the other systems. This is in stark contrast with the cur

Addressing climate change and the collapse of ecosystems without threatening the economy, while simultaneously improving the well-being of all people, and ensuring social justice and equality seems to be the largest challenge in the history of mankind. So far, all the efforts to address growing environmental and human problems through technological solutions and half-hearted policy measures have b