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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

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

In Networked Control Systems, time-varying delays and loss of data are two important problems to be taken into account. In this paper, in order to face them, the design of a predictor-observer for possible unstable systems is proposed. A delay-dependent time varying stability condition is expressed in terms of LMIs. Stability and robustness is proved.

Theoretically, electron microscopy and scanning probe microscopy offer information on a scale beyond the optical microscope. However, the quality of the micrograph and the obtained information is limited by the sample preparation. Each sample has its own characteristics that need special precautions, meaning that sample preparation is a continuously developing science. In this thesis several micro

Synovial fluid was collected from patients with recent knee injury and from patients with early or late stage osteoarthritis. Chondroitin sulfate-substituted aggrecan fragments present in these fluids, and in normal bovine synovial fluid, were purified by cesium chloride gradient centrifugation, enzymically deglycosylated and fractionated by gel filtration on Superose-12. Each sample contained two

Objective: To update evidence for available therapies in the treatment of hip and knee osteoarthritis (OA) and to examine whether research evidence has changed from 31 January 2006 to 31 January 2009. Methods: A systematic literature search was undertaken using MEDLINE, EMBASE, CINAHL, AMED, Science Citation Index and the Cochrane Library. The quality of studies was assessed. Effect sizes (ESs) an