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Wireless Channel Modeling and Reconstruction in Massive MIMO Systems

The past few years have witnessed dramatic growth in the number of wirelessly connected devices, which will continue to increase in the future. Following this trend, the capacity of the wireless networks has been enhanced to provide high-quality service to tens of billions of devices. At the same time, in response to the network enhancement, each device unashamedly requests more and more throughpu

Properties of the CsI(Tl) detector elements of the CALIFA detector

In the RB experiment at FAIR, charged particles with energies up to 600 MeV and forward boosted -rays with energies up to 20 MeV need to be detected in scattering experiments. Calorimeters for nuclear physics experiments of this kind, using relativistic radioactive ion beams, require high energy resolution and high efficiency for simultaneous detection of strongly Doppler shifted -rays and high-en

Genetic correlations and their dependence on environmental similarity : insights from livestock data

Genetic correlations for a trait across environments are predicted to decrease as environments diverge. However, estimates ofgenetic correlations from natural populations are typically defined across a limited environmental range and prone to very largestandard errors, making it difficult to test this prediction. We address the importance of environmental distance on genetic cor-relations by employiGenetic correlations for a trait across environments are predicted to decrease as environments diverge. However, estimates of genetic correlations from natural populations are typically defined across a limited environmental range and prone to very large standard errors, making it difficult to test this prediction. We address the importance of environmental distance on genetic correlations by empl

Future development plans for the MAX IV light source: Pushing further towards higher brightness and coherence

The commissioning of the MAX IV synchrotron radiation facility in Lund marks the dawn of a new generation of storage-ring-based light sources. This new generation delivers one order of magnitude higher performance and allows realization of groundbreaking experiments on a variety of systems and materials at the atomic and molecular levels. This paper reviews the conceptual basis of the MAX IV desig

Metallmatriskompositer i masstillverkade komponenter och produkter : - MMC 2016-2018

Föreliggande rapport beskriver forskningsarbetet inom projektet: ”Utveckling av MMC för högpresterande aluminiumkomponenter – Vinnova 2015–05072 som leds av Marie Fredriksson vid Swerea SWECAST i Jönköping. Redovisade resultat bygger också på tidigare kunskaper och tidigare projekt som forskargruppen vid Lunds universitet genomfört. Resultaten från detta arbete visar att det kan vara fullt möjligt

Fake drugs that could kill are on the rise in Western countries – here’s why

Fake medicines – illegal and substandard pharmaceuticals – have until now largely been a problem in low and middle-income countries. Ranging from lifestyle products to lifesaving medicines, such products are now also on the rise in the Western world. The spread is concerning, as fake medicines can be completely ineffective or extremely toxic.

Rare orbital manifestations and vasculitis, giant cell arteritis or side effects of zoledronic acid infusion?

Giant cell arteritis (GCA), affects an age group where osteoporosis is common. A well-established treatment for osteoporosis is medication with bisphosphonates. Bisphosphonates are overall well-tolerated but can trigger several different acute inflammatory reactions with systemic features and symptoms and signs from the ocular and musculoskeletal system, all of which resemble those of GCA. Here is

The European Union and the Brexit Dilemma : A very British Problem?

This paper discusses the key legal issues arising from the constitutional conceptions of both the EU and the UK in the latter’s withdrawal process. It argues that the adherent Brexit dilemma is mainly the result of the UK’s non-codified constitution on the one hand, exposing legal uncertainty over institutional procedures, regional involvement, or the precise status of international law. Neverthel

Observation of coherent synchrotron radiation from a 1 mm electron bunch at the MAX-I storage ring

The coherent generation of synchrotron radiation by an electron storage ring is predicted for wavelengths equal to or longer than the electron bunch length. With typical bunch lengths of approximately 1 cm, diffraction and chamber- screening effects have so-far blocked observation of coherent radiation from a conventional radiation beam line. In the low-energy, second-generation light source MAX-I

Landau cavities at MAX II

Passive Landau cavities have been built, installed and taken into regular operation in the MAX II ring. The purpose of the Landau damping system is twofold: to decrease the energy spread of the beam induced by coupled bunch oscillations and to increase the Touschek life-time. The cavities are of the pillbox type operated at 1500 MHz, the third harmonic of the main RF. This paper describes the desi

Experiences with the narrow gap undulator at MAX-lab

An undulator with short poles (period 24 mm) and extremely narrow gap (magnet gap 7.7 mm) using a squeezable vacuum chamber has been installed and is in operation at the MAX-lab 550 MeV storage ring. The device operates with a vacuum chamber aperture down to 6.2 mm. The behaviour of the storage ring concerning lifetime, emittance, tune shift and closed orbit is well described by conventional model

Beam profile measurements at MAX

An electron beam profile monitor system is described. It utilizes the visible bending magnet synchrotron radiation (SR) to form an image of the beam. A model for calculating diffraction and depth of field effects is introduced. Assuming a Gaussian distributed electron beam, the relation between beam image size and actual beam size is then calculated with this model, for a number of practical measu

Some experiments on synchrotron radiation induced desorption at MAX

At the synchrotron radiation facility MAX, the rest gas pressure in the storage rings is dominated by synchrotron radiation induced gas desorption. This desorption decreases with accumulated photon dose. The rate of decrease, or conditioning, is of greatest importance, since an acceptable machine performance, after opening the vacuum system, is highly dependent on the vacuum recovery. In MAX II th

Positron production for ESRF

In this report, we first discuss some different pre-injector possibilities for the ESRF booster synchrotron, using estimated machine performances. We then focus on the commercially available linac schemes carrying out more detailed calculations. We also look into the possibility of recyling the particles through the linacs.