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Popular Abstract in Swedish Idag tar de flesta för givet att man när och var som helst kan komma åt sin e-post, ladda upp bilder till Facebook eller söka kunskap på Wikipedia från sin mobiltelefon eller dator. Den trådlösa teknologi som gjort detta möjligt har utvecklats oerhört det senaste årtiondet, men behöver utvecklas ännu mer för att möta det ökande behovet av trådlös kommunikation. I dennaThe traffic in wireless networks has been showing an exponential growth over the last decade. In order to meet the demand, and support a continuation of this growth, the scarce radio resources need to be efficiently used. The use of multiple antenna (MIMO) systems and iterative (turbo) receivers has significantly improved the realizable system performance. Still, many challenges exist in the devel

This paper discusses importance of a strategic planning and design process when developing long-term space exploration missions both robotic and manned. The discussion begins with reviewing current and/or traditional international perspectives on space development at the American, Russian and European space agencies. Some analogies and comparisons will be drawn upon analysis of several internation

The normal approach to digital control is to sample periodically in time. Using an analog of integration theory we can call this Riemann sampling. Lebesgue sampling or event based sampling is an alternative to Riemann sampling. It means that signals are sampled only when measurements pass certain limits. In this paper it is shown that Lebesgue sampling gives better performance for some simple syst

Using DTT and iodoacetamide as a novel irreversible method to inhibit endogenous violaxanthin de-epoxidase, we found that violaxanthin could be converted into zeaxanthin from both sides of the thylakoid membrane provided that purified violaxanthin de-epoxidase was added. The maximum conversion was the same from both sides of the membrane. Temperature was found to have a strong influence both on th

The max-bisection and min-bisection problems are to find a partition of the vertices of a graph into two equal size subsets that, respectively, maximizes or minimizes the number of edges with endpoints in both subsets. We design the first polynomial time approximation scheme for the max-bisection problem on arbitrary planar graphs solving a long-standing open problem. The method of solution involv

Background: Exhaled breath condensate (EBC) is simple to cottect and as such a non-invasive method that has attracted substantial interest in the last few years. However, several methodological concerns have been raised and it has been difficult to reproduce results between different centres. Because of low concentrations of inflammatory markers, potential loss in the sampling system may have grea

In this paper, a number of challenges, which need to be overcome if multivariate monitoring of wastewater treatment operation is to be successful, are presented. For each challenge, one or several solutions are discussed. The methodologies are illustrated using an example from full-scale wastewater treatment operation. Some guidelines regarding choices of methods and implementation aspects are giv

There is a need for objective and quantitative methods for measuring posture and movement, so that, for instance, exposure-response relationships for work-related musculoskeletal disorders can be established. Inclinometry data have been obtained from triaxial accelerometers based on uniaxial solid-state accelerometers used in conjunction with a computer program to perform co-ordinate transformatio

The utilisation of biofuels is attracting growing support from the European Union and member states as a strategy to tackle climate change, enhance energy security, and contribute to regional development. This paper describes, compares, and analyses the markets for biofuels in Germany and the UK. The introduction of biofuels for transport in these member states provides contrasting pictures, and t

PURPOSE: CT and MR imaging are appropriate modalities for imaging of the liver. Contrast media are used to obtain a greater difference in attenuation and signal intensity, respectively, between normal liver tissue and focal lesions. However, no studies have attempted to determine whether physiological nutritional status of the liver during fasting is of importance for the native signal of normal l

Medical physics education and training requires the use of extensive imaging material and specific explanations. These requirements provide an excellent background for application of e-Learning. The EU projects Consortia EMERALD and EMIT developed five volumes of such materials, now used in 65 countries. EMERALD developed e-Learning materials in three areas of medical physics (X-ray diagnostic rad

This paper presents an application of the Hilbert-Huang transform (HHT) and ensemble correlation for detection of the transient evoked otoacoustic emissions (TEOAEs), and high resolution time-frequency mapping. The HHT provides a powerful tool for nonlinear analysis of nonstationary signals such as TEOAEs. Since the HHT itself does not distinguish between signal and noise it was used with ensemble

We present a flexible and efficient program package written in C++, PROFASI, for simulating protein folding and aggregation. The systems are modeled using an all-atom description of the protein chains with only torsional degrees of freedom, and implicit water. The program package has a modular structure that makes the interaction potential easy to modify. The currently implemented potential is abl

This thesis concerns two interrelated subjects of heat and mass transfer processes. The first one concerns mainly experimental measurements, with a subsequent development of a calculation procedure, of the thermal and hydraulic performances, experimental methods and evaluation procedures applied on various plate heat exchangers (PHEs) as evaporators with the refrigerant ammonia as working medium.

Women are a neglected group for cardiovascular disease. Whereas young women tend to have lower incidences of coronary artery disease, stroke and myocardial infarctions than men, the situation changes drastically at menopause, after which women are at greater risk than men. Despite this, women at all ages receive less treatment, less attention and not enough information about health risks. Most ris

We present the FERRUM Project, an international collaboration aiming at a production and evaluation of oscillator strengths (transition probabilities) of selected spectral lines of singly ionized iron group elements, that are of astrophysical relevance. The results obtained include measurements and calculations of permitted and forbidden lines of Fe II. The data have been applied to both emission

Absorption microspectrophotometry has been shown to be of considerable help to probe crystalline proteins containing chromophores, metal centres, or coloured substrates/co-factors. Absorption spectra contribute to the proper interpretation of crystallographic structures, especially when transient intermediate states are studied. Here it is shown that fluorescence microspectrophotometry might also

Background Many patients who are discharged from the hospital without receiving a clear-cut diagnosis of their chest pain continue to consume health care because of disabling physical and psychological symptoms. By identifying their experiences and concerns following hospitalization, an empirical basis for discussions on ways of improving the care of these particular patients will be obtained. Me