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Popular Abstract in Swedish Denna avhandling behandlar två ämnen inom trådlös kommunikation: interferens mellan frekvenshoppande (FH) nätverk och fleranvändardiversitet. I arbetet på FH nätverk undersöks ett system där frekvenshopp används för att möjliggöra samtidig tillgång till kanalen för multipla okoordinerade nätverk. Detta åstadkoms genom att frekvenshoppen sker varje gång ett ny paket skaThis thesis deals with two topics in wireless communications: interference between frequency-hopping (FH) networks, and multiuser diversity. The work on FH treats a system where FH is used to provide simultaneous access to the channel for multiple uncoordinated wireless networks. This is achieved by performing frequency hops on a packet-by-packet basis, and letting the sequence of hopping frequen

The mobile phone is one of the most widespread devices with rendering capabilities. Those capabilities have been very limited because the resources on such devices are extremely scarce; small amounts of memory, little bandwidth, little chip area dedicated for special purposes, and limited power consumption. The small display resolutions present a further challenge; the angle subtended by a pixel i

Abstract is not available

Popular Abstract in Swedish Under kvartärtiden (de senaste 2,6 miljoner åren) har istider (glacialer) och mellanistider (interglacialer) avlös varandra. Mellanistider är perioder (ca 10 000 år) mellan istider (ca 100 000 år), vilket innebär att istid varit det normala under kvartärtiden och att Holocene, den istid vi nu lever i, endast representerar ett kortare intervall. Under istiderna täckte inThe aim of this thesis was to reconstruct the glaciodynamics, deglacial landforms, isostatic uplift and to date the deglaciation. Glaciodynamics and deglacial landforms were focused on to provide a process and depositional model for De Geer moraine and Niemisel moraine and to reveal their internal and spatial relationship, based on detailed sedimentological and structural investigations. The isost

Popular Abstract in Swedish Inledningen syftar till att ge en översikt över Swedenborgs levnadslopp och ge en viss orientering i litteraturen kring honom. Det visar sig att det saknas en grundlig idéhistorisk studie över hans tidiga mekanistiska naturfilosofi. Föreliggande bok kan sägas vara en kognitiv idéhistoria som har siktet inställt på hur han tänkte. I arbetet med Swedenborgs naturfilosofi The Swedish natural philosopher Emanuel Swedenborg (1688–1772) thought in his early scientific career that the world was like a gigantic machine, following the laws of mechanics and geometry. The work presented here is a study of his mechanistic worldview and metaphorical way of thinking up to the year 1734, examining most of his fields of interest, from geometry and metaphysics to technology and

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A new explicit WET model for the turbulent heat fluxes is derived and developed from the transport equation of the scalar passive flux. In order to study the performance of the model itself, all other turbulent quantities are taken from a DNS channel flow data-base and thus the error source has been minimized. This anisotropic eddy diffusivity model can be solved with a two-equation model for the

Abstract is not available

From the existing full set of international policy instruments on forests, eight core components are identified and submitted to two differing assessments. The first (consistency assessment) uses a policy design approach to match the core components with their goals, policy tools, target group preferences and justifications for the choice of goals and policy tools. The second (compatibility assess

This thesis consists of theoretical studies of the evolutionary consequences of environmental change in ecological communities. Paper I and II are concerned with the origin of diversity, i.e. how a single lineage can split into two, under the influence of selection induced by competitive interactions (evolutionary branching). In paper I we find that environmental fluctuations may affect the likeli

Experiments relying on tomographic reconstruction of soot emission and absorption offer relatively simple and inexpensive ways to image both soot concentration and temperature in axisymmetric flames. Because the tomography problem is mathematically ill-posed, however, special measures have to be taken to ensure an accurate solution. This paper describes the application of one such measure, Tikhono

Popular Abstract in Swedish I över 40 år har det varit möjligt att operera förslitning (artros) av höftleden med en konstgjord led. De allra flesta av de cirka 12 000 patienter, som opereras i Sverige varje år med så kallad höftplastik, får en ny höftkula av metall och en ny ledpanna av plast. De nya leddelarna förankras oftast i lårbenet (kulan) respektive bäckenbenet (pannan) med bencement, ett 144 consecutive hip revisions performed with morselized allograft bone and cement were followed up to 5 years after surgery. In 49 hips patient outcome was evaluated with the Nottingham Health Profile (NHP) questionnaire and Charnley hip scores in 47 hips prosthetic fixation was evaluated with radiostereometry (RSA)and in all 144 hips risks and complications were recorded using a prspective protoc

Popular Abstract in Swedish Häri avhandlas tesen att bättre insikt i kemisk jordförorening med tjärämnen kan erhållas genom två analytiska begrepp: tillgänglighet och kemisk aktivitet. Tillgänglighet syftar på andelen av den totala mängden PAH som är tillgänglig för processer vilka sker utanför jordpartiklarna. Det andra begreppet, kemisk aktivitet, är termodynamiskt. Den kemiska aktiviteten är häThis thesis proposes the use of two concepts: accessibility and chemical activity. Accessibility describes the mass quantity of PAHs that is or can become available within a given time span and under given conditions. Chemical activity quantifies the energetic state of the PAHs that determines the potential for spontaneous physicochemical processes, such as diffusion and partitioning. Chemical act