Search results
Filter
Filetype
Your search for "*" yielded 540357 hits
Exploiting antenna correlation in measured massive MIMO channels
We investigate antenna correlation of an M-antenna massive multiple-input multiple-output (MIMO) setup with the purpose of obtaining a low-rank representation of the instantaneous massive MIMO channel. Low-rank representation bases using short-term and long-term antenna correlation statistics are defined, and their performance is evaluated with data sets obtained from channel measurements in both
Performance evaluation of CoMP transmission schemes using measurements versus the COST 2100 channel model
Coordinated Multi Point (CoMP) transmission and reception techniques are used in order to improve the performance of single or multiple cells in wireless systems. A system using CoMP techniques is capable of jointly optimizing its transmission and/or reception and, hence, achieving higher performance. In this work, performance evaluation of three CoMP techniques are performed based on simulations
Evaluation of the effect of base station antenna polarization on the performance of CoMP transmission techniques based on synchronous multi-link measurements
In this paper, the effect of polarization on the downlink sum-rate capacity of multi-user Cooperative Multi-Point (CoMP) systems using synchronous multi-link measurement data, for two different antenna arrangements, is studied. In the first setup, four antenna patches each of which with dual-polarized antenna elements at the base station (BS) with inter-patch distance varied from half wavelength tIn this paper, the effect of polarization on the downlink achievable sum-rate of multi-user Cooperative Multi-Point (CoMP) systems is studied using synchronous multi-link channel measurements with two different antenna arrangements. In the first setup, four dual-polarized antenna patches with inter-patch distance varied from half wavelength to 8 m are considered at the base station (BS). In the se
On The Coherence Time of Fiber-Based Distributed Antenna Systems
The possibility of using radio over fiber (RoF) analog transmissions to characterize the wireless propagation channel of distributed antenna systems is investigated. In particular, the coherence time of kilometer-long, fiber-based networks is analyzed. Joint measurements of the phase noise of parallel links to the same site (intra-site) and to different sites (inter-site) in such a network are pre
Analysing documents through fieldwork
Energy/reliability trade-offs in fault-tolerant event-triggered distributed embedded systems
This paper presents an approach to the synthesis of low-power fault-tolerant hard real-time applications mapped on distributed heterogeneous embedded systems. Our synthesis approach decides the mapping of tasks to processing elements, as well as the voltage and frequency levels for executing each task, such that transient faults are tolerated, the timing constraints of the application are satisfie
Variations of information literacy and different views on democracy and citizenship
Recombination dynamics in aerotaxy-grown Zn-doped GaAs nanowires
In this paper we have investigated the dynamics of photo-generated charge carriers in a series of aerotaxy-grown GaAs nanowires (NWs) with different levels of Zn doping. Time-resolved photo-induced luminescence and transient absorption have been employed to investigate radiative (band edge transition) and non-radiative charge recombination processes, respectively. We find that the photo-luminescen
Clinical, optical coherence tomography, and fundus autofluorescence findings in patients with intraocular tumors
PURPOSE: To describe clinical, optical coherence tomography (OCT) and fundus autofluorescence (FAF) findings in patients with intraocular tumors and determine if OCT and FAF could be helpful in the differential diagnosis and management of different choroidal tumors.METHODS: Forty-nine patients with untreated, macular, midperipheral, and extrapapillary intraocular tumors were included. All patients
Tumor-directed immunotherapy can generate tumor-specific T cell responses through localized co-stimulation
The most important goals for the field of immuno-oncology are to improve the response rate and increase the number of tumor indications that respond to immunotherapy, without increasing adverse side effects. One approach to achieve these goals is to use tumor-directed immunotherapy, i.e., to focus the immune activation to the most relevant part of the immune system. This may improve anti-tumor eff
Thyroid function and survival following breast cancer
Background: Thyroid function has been associated with breast cancer risk, and breast cancer cell growth and proliferation. It is not clear whether thyroid function affects prognosis following breast cancer but, if so, this could have an important clinical impact. The present study analysed prospectively collected measurements of free tri-iodothyronine (T3), free thyroxine (T4), thyroid-stimulating
CMOS Integrated Remote Antenna Unit for Fiber-Fed Distributed MIMO Systems
A fully integrated remote antenna unit (RAU) intended for fiber-fed distributed multiple-input multiple-output systems is presented. The circuit is designed for narrowband (60 MHz) time-division duplex systems, where an IF over fiber approach is chosen to facilitate the use of low-cost optical components and integrated photodetectors. A novel antenna switch control scheme is introduced, which enab
Association of breast cancer risk in BRCA1 and BRCA2 mutation carriers with genetic variants showing differential allelic expression : identification of a modifier of breast cancer risk at locus 11q22.3
Purpose: Cis-acting regulatory SNPs resulting in differential allelic expression (DAE) may, in part, explain the underlying phenotypic variation associated with many complex diseases. To investigate whether common variants associated with DAE were involved in breast cancer susceptibility among BRCA1 and BRCA2 mutation carriers, a list of 175 genes was developed based of their involvement in cancer
Safer drug use in primary care - a pilot intervention study to identify improvement needs and make agreements for change in five Swedish primary care units
Background: There is an urgent need to improve patient safety in the area of medication treatment among the elderly. The aim of this study was to explore which improvement needs and strengths, relating to medication safety, arise from a multi-professional intervention in primary care and further to describe and follow up on the agreements for change that were established within the intervention. M
Linking Swedish health data registers to establish a research database and a shared decision-making tool in hip replacement
Background: Sweden offers a unique opportunity to researchers to construct comprehensive databases that encompass a wide variety of healthcare related data. Statistics Sweden and the National Board of Health and Welfare collect individual level data for all Swedish residents that ranges from medical diagnoses to socioeconomic information. In addition to the information collected by governmental ag
Lipid Spontaneous Curvatures Estimated from Temperature-Dependent Changes in Inverse Hexagonal Phase Lattice Parameters : Effects of Metal Cations
Recently we reported a method for estimating the spontaneous curvatures of lipids from temperature-dependent changes in the lattice parameter of inverse hexagonal liquid crystal phases of binary lipid mixtures. This method makes use of 1,2-dioleoyl-sn-glycerol-3-phosphoethanolamine (DOPE) as a host lipid, which preferentially forms an inverse hexagonal phase to which a guest lipid of unknown spont
Association of CD247 (CD3ζ) gene polymorphisms with T1D and AITD in the population of northern Sweden
Background: T1D and AITD are autoimmune disorders commonly occurring in the same family and even in the same individual. The genetic contribution to these disorders is complex making uncovering of susceptibility genes very challenging. The general aim of this study was to identify loci and genes contributing to T1D/AITD susceptibility. Our strategy was to perform linkage and association studies in
Effect of realistic nuclear charge distributions on isotope shifts and progress towards the extraction of higher-order nuclear radial moments
Atomic spectral lines from different isotopes display a small shift in energy, commonly referred to as the line isotope shift. One of the components of the isotope shift is the field shift, which depends on the extent and the shape of the nuclear charge density distribution. The purpose of this work is to investigate how sensitive field shifts are with respect to variations in the nuclear size and