A new peak-to-average power reduction approach for OFDM has been addressed. Two-dimensional pilot-symbol assisted modulation (2D-PSAM) is employed in coherent OFDM for channel estimation and it is based on inserting known symbols spreaded out throughout the 2D time-frequency grid. We show that these scattered symbols can also be employed to perform distortionless peak power reduction, with a negli

In this thesis I have summarised my work on the analysis and improvement of xylose utilisation by recombinant S. cerevisiae. A metabolic flux model was developed and used to analyse the intracellular fluxes in the recombinant xylose utilising S. cerevisiae TMB 3001 cultivated in chemostat at various dilution rates and xylose/glucose concentrations. Xylose uptake increased with xylose concentration

The principal noise source for a jet engine is associated with the jet exhaust. The acoustical field that is generated by a jet engine before the take-off is considered. The turbulent jet and the mixing of the hot exhaust gas with the cold surrounding air forms an acoustical source. The compressible Navier-Stokes equations describe both flow field as well as sound generation. The acoustic theory u

Popular Abstract in Swedish Polymergeler och deras interaktioner med joniska surfaktanter. Olika typer av hydrofoba polymerer och hydrophobmodifierade polymerer tvärbinds kemisk till geler. Dessa geler tillhör gruppen responsiva geler, vilket betyder att gelerna ändrar sin volym under yttre påverkan. Gelernas volymändring studeras vid tillsats av olika joniska surfaktanter, vid tillsats av saltThe response on chemically crosslinked gels and polymer solutions on the addition of ionic surfactants and/or addition of salt at different temperatures have been studied. All polymers studied are water soluble and slightly hydrophobic or hydrophobically modified. Because of their hydrophobicity the polymers have a strong tendency to associate, both with themselves and with surfactants. Another i

Abstract is not available

The Simplex S^D is the sample space of a D-part composition. There are only a few distributions defined on the Simplex and even fewer defined on the Cartesian product S^D x S^D. Based on the Dirichlet distribution, defined on S^D, we propose a new bicompositional Dirichlet distribution defined on S^D x S^D, and examine some of its properties, such as moments as well as marginal and conditional dis

Popular Abstract in Swedish Inom området diagnostisk nuklearmedicin används radioaktiva läkemedel som ges (administreras) till patienterna i syfte att diagnostisera ett antal olika sjukdomstillstånd. Då man tar fram nya radioaktiva läkemedel för användning inom diagnostisk nuklearmedicin handlar det många gånger om att uppskatta mängden av ett visst upptag av radiofarmakat i olika organ och vävnadAn essential part of the development of new radiopharmaceuticals for use in diagnostic nuclear medicine is the determination of its biokinetic properties. The uptake and turn-over of the radiopharmaceutical in the source organs is of great interest since this could determine whether the radiopharmaceutical would be suitable for clinical use or not. It is also important that the biokinetics and dos