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Massive MIMO in Real Propagation Environments: Do All Antennas Contribute Equally?

Massive MIMO can greatly increase both spectral and transmit-energy efficiency. This is achieved by allowing the number of antennas and RF chains to grow very large. However, the challenges include high system complexity and hardware energy consumption. Here we investigate the possibilities to reduce the required number of RF chains, by performing antenna selection. While this approach is not a ve

Structure changes in Er-160 from low to ultrahigh spin

A spectroscopic investigation of the gamma decays from excited states in Er-160 has been performed in order to study the changing structural properties exhibited from low spin up toward ultrahigh spin (I similar to 60 h). The nucleus Er-160 was populated by the reaction Cd-116(Ca-48,4n gamma) at a beam energy of 215 MeV, and resulting gamma decays were studied using the Gammasphere spectrometer. N

Laminar burning velocities of n-heptane, iso-octane, ethanol and their binary and tertiary mixtures

Measurements of the adiabatic laminar burning velocities of n-heptane, iso-octane, ethanol and their binary and tertiary mixtures are reported. Non-stretched flames were stabilized on a perforated plate burner at 1 atm. The Heat Flux method was used to determine burning velocities under conditions when the net heat loss from the flame to the burner is zero. Initial temperatures of the gas mixtures

The Ferrum project: experimental and theoretical transition rates of forbidden [Sc II] lines and radiative lifetimes of metastable Sc II levels

Context. In many plasmas, long-lived metastable atomic levels are depopulated by collisions (quenched) before they decay radiatively. In low-density regions, however, the low collision rate may allow depopulation by electric dipole (E1) forbidden radiative transitions, so-called forbidden lines (mainly M1 and E2 transitions). If the atomic transition data are known, these lines are indicators of p

On Microstructural Analysis of Porous Media Existing in Fuel Cells Using the Lattice Boltzmann Method

This Licentiate thesis aims to gain understanding related to the fluid behavior in porous media existent in fuel cells (FCs) at microscale. In order to achieve this; the widely used methodology for solving problems in porous media has been applied, the Lattice Boltzmann Method (LBM). LBM presents several advantages to solve problems where the microstructural architecture is complex. The introduc

Genomics based analysis of interactions between developing B-lymphocytes and stromal cells reveal complex interactions and two-way communication

Background: The use of functional genomics has largely increased our understanding of cell biology and promises to help the development of systems biology needed to understand the complex order of events that regulates cellular differentiation in vivo. One model system clearly dependent on the integration of extra and intra cellular signals is the development of B-lymphocytes from hematopoietic st

Multi-target Tracking Using on-line Viterbi Optimisation and Stochastic Modelling

To study and compare the safety of intersection, traffic scientists today typically manually monitor the intersection during several days and count how often certain events such as evasive manoeuvres occur. This is a laboursome and costly procedure. The aim of this thesis is to provide tools that can reduce the amount of manual labour required by using automated video analytics. Two methods for cr

Genomic profiling of breast cancer by microarray-based technology and bioinformatics

Popular Abstract in Swedish Bröstcancer är den vanligaste cancerformen bland kvinnor i Sverige. Mer än 7000 kvinnor insjuknar varje år i bröstcancer, och cirka 1500 dör i sjukdomen. Incidensen av bröstcancer har stigit kontinuerligt sedan 1970-talet, och man uppskattar att en av tio kvinnor i Sverige kommer att utveckla bröstcancer någon gång under sin livstid. Den relativa överlevnaden i sjukdomeCancer is a genetic disease that arises when a cell acquires unlimited growth potential through a series of mutational events, which target genes essential for normal cell control and maintenance. Breast cancer is one of the most frequent malignancies in women worldwide, and it is characterized by heterogeneous tumor biology, histological subtypes, variable prognosis and variable responsiveness to

High-Quality Spatio-Temporal Rendering using Semi-Analytical Visibility

We present a novel visibility algorithm for rendering motion blur with per-pixel anti-aliasing. Our algorithm uses a number of line samples over a rectangular group of pixels, and together with the time dimension, a two-dimensional spatio-temporal visibility problem needs to be solved per line sample. In a coarse culling step, our algorithm first uses a bounding volume hierarchy to rapidly remove

Conformity assessment for machine graded timber by using output control

In the Nordic countries machine strength grading of structural timber is becoming increasingly important. A new standard, EN 14081, which allows CE-marking of strength graded structural timber was recently accepted. This standard allows both machinecontrol and output control as methods for controlling the graded timber. Machine control is most commonly used in Europe. The project reported here dea

Molecular evidence for hierarchical transcriptional lineage priming in fetal and adult stem cells and multipotent progenitors.

Recent studies implicated the existence of adult lymphoid-primed multipotent progenitors (LMPPs) with little or no megakaryocyte-erythroid potential, questioning common myeloid and lymphoid progenitors as obligate intermediates in hematopoietic stem cell (HSC) lineage commitment. However, the existence of LMPPs remains contentious. Herein, global and single-cell analyses revealed a hierarchical or

Tumour therapy with radionuclides: assessment of progress and problems

Radionuclide therapy is a promising modality for treatment of tumours of haematopoietic origin while the success for treatment of solid tumours so far has been limited. The authors consider radionuclide therapy mainly as a method to eradicate disseminated tumour cells and small metastases while bulky tumours and large metastases have to be treated surgically or by external radiation therapy. The p

Atomic structure studies using fusion plasmas

Atomic spectroscopy plays an important role in fusion research and extensive knowledge of atomic parameters is needed for plasma diagnostics. However, a magnetically confined hot plasma can be considered as a spectroscopic fight source which has some unique properties, including high temperature and low density. Fusion devices can therefore be used to tackle problems in basic atomic physics. This

Secondhand Smoke Exposure Causes Bronchial Hyperreactivity via Transcriptionally Upregulated Endothelin and 5-hydroxytryptamine 2A Receptors.

Cigarette smoke exposure is strongly associated with airway hyperreactivity (AHR) which is the main characteristic seen in asthma. The intracellular MAPK signaling pathways are suggested to be associated with the airway damage to the AHR. In the present study, we hypothesize that secondhand cigarette smoke (SHS) exposure upregulates the bronchial contractile receptors via activation of the Raf/ERK