The influence of a barrier on the acoustic field is investigated using an expansion of the compressible Navier-Stokes equations. Large Eddy Simulations (LES) is used to account for the acoustical sources and the equation for the acoustic density fluctuation accounts for the propagation of the acoustics waves. This combined approach enhances numerical efficiency while maintaining good accuracy. The

A low phase noise 2.4 GHz voltage controlled oscillator (VCO) with 1 V supply is presented. The VCO is based on the differential negative resistance oscillator with the tail current source replaced by an inductor. The inductor both improves the noise factor of the oscillator and enables maximum voltage swing over the tank. The amplitude limitation which is usually set by the tail current source is

In Southern Sweden, production of renewable energy from crop residues digestion is viewed as a worthwhile alternative. Also, the process gives valuable mineralised nitrogen as a by-product, which when produced at farm-scale can be recycled for ecological farming. It is difficult to achieve economic utilisation of crop residues in centralised slurry digestion, mainly because of the greater transpor

Machining is an important and widely spread manufacturing method which should not be neglected while striving towards sustainable production. Several previous articles have discussed sustainable machining and different approaches towards reaching this goal. However, few have discussed the influence of the cutting tool utilization on the sustainability during machining. This article presents a nove

Popular Abstract in Swedish Helkroppsinnehållet av radioaktivt cesium mättes regelbundet hos en grupp individer bosatta i Lund med omnejd mellan åren 1960 och 1994. I denna avhandling presenteras en utvärdering av resultaten från denna mätserie. Ekologisk halveringstid och överföring från markbeläggning till människa via livsmedel har bestämts genom analys av den genomsnittliga helkroppsinnehålletThe whole-body content of radiocaesium was measured in a South-Swedish urban group of people residing in the city of Lund (55.7°N, 13.2°E) between 1960 and 1994. The results from the survey have been analysed in order to estimate the ecological half-time, Teco,eff, of fallout radiocaesium and the aggregate transfer from ground deposition to man in the region. After 1987, the biological half-times,

Multi-particle production in the central and forward (proton) rapidity region is studied in photoproduction and deep inelastic scattering (DIS). The measurements in the forward region are a factor of similar to 2 larger than QCD predictions based on the DGLAP evolution equations. The central rapidity region is rather well described. Searches for instanton induced processes in DIS are presented.

Popular Abstract in Swedish Malign hypertermi, ärftligt och farligt vid narkos – hur diagnostiseras det ? I april 1960 sövdes en yngling i Australien. Han var mycket orolig därför att tio släktingar dött av eter-narkos. Han sövdes i stället med ett nytt medel – halotan, det höll på att kosta även honom livet. En kortfattad fallbeskrivning i Lancet fick stor uppmärksamhet och på andra ställen i väMalignant hyperthermia (MH) susceptibility is a rare inherited muscular disorder, which may cause a lethal increase in metabolism during anaesthesia with certain commonly used anaesthetic. Susceptible individuals are without any signs or symptoms. It is important to identify individuals at risk, since the MH reaction is preventable. Susceptibility to MH is diagnosed with an in vitro contracture te

Summary form only given. Resonant tunneling based devices are an intriguing set of devices with promising high speed, low power and high functionality capabilities. We have developed an technology to embed metallic features on the nm-scale inside a semiconductor. By combining such metallic features and heterostructures we have developed a new type of tunneling transistor, the so called Resonant Tu