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A Low Complexity Massive MIMO Detection Scheme Using Angular-Domain Processing

Signal processing complexity and required memory become problematic in massive MIMO systems as the dimension of channel state information (CSI) matrix grows significantly with the large number of antennas and users. To address these challenges, we propose the first angular-domain massive MIMO detection scheme, which is based on three concepts: transferring the baseband processing from the spatial

A Low Latency FFT/IFFT Architecture for Massive MIMO Systems Utilizing OFDM Guard Bands

A considerable part of latency in the baseband of massive multiple-input multiple-output (MIMO) systems is introduced by orthogonal frequency division multiplexing (OFDM) (de)modulation. To address the low-latency demand of massive MIMO systems, a fast Fourier transform (FFT) processor and corresponding reordering scheme are proposed, which reduce the processing latency and reordering latency of O

The Coagulopathy of Acute Type A Aortic Dissection : A Prospective, Observational Study

Objective: To evaluate the hemostatic system in patients undergoing surgery for acute type A aortic dissection (ATAAD) compared with those undergoing elective aortic procedures. Design: This was a prospective, observational study. Setting: The study was performed at a single university hospital. Participants: Twenty-five patients with ATAAD were compared with 20 control patients undergoing electi

A robust method for calibration of eye tracking data recorded during nystagmus

Eye tracking is a useful tool when studying the oscillatory eye movements associated with nystagmus. However, this oscillatory nature of nystagmus is problematic during calibration since it introduces uncertainty about where the person is actually looking. This renders comparisons between separate recordings unreliable. Still, the influence of the calibration protocol on eye movement data from peo

Physical-density integral equation methods for scattering from multi-dielectric cylinders

An integral equation-based numerical method for scattering from multi-dielectric cylinders is presented. Electromagnetic fields are represented via layer potentials in terms of surface densities with physical interpretations. The existence of null-field representations then adds superior flexibility to the modeling. Local representations are used for fast field evaluation at points away from their

Nonlinear Estimation of Variables for Heat Release Calculation Using a Gradient Method

Advanced combustion such as the partially premixed combustion (PPC) is characterized by high energy efficiency. However, they are sensitive to the inlet condition and injection of a combustion engine. Therefore, it is essential to use combustion feedback. The accuracy of the feedback variables, derived from the cylinder pressure signal, is crucial for effective combustion feedback control. This pa

First assessment of the plant phenology index (PPI) for estimating gross primary productivity in African semi-arid ecosystems

The importance of semi-arid ecosystems in the global carbon cycle as sinks for CO 2 emissions has recently been highlighted. Africa is a carbon sink and nearly half its area comprises arid and semi-arid ecosystems. However, there are uncertainties regarding CO 2 fluxes for semi-arid ecosystems in Africa, particularly savannas and dry tropical woodlands. In order to improve on existing remote-se

Comparison of Bayesian techniques for the before–after evaluation of the safety effectiveness of short 2+1 road sections

In evaluating the effectiveness of a road safety treatment, the regression to the mean phenomenon is a cause for concern because of a possible overestimation of benefits. Therefore, Bayesian approaches are usually suggested as the most appropriate methodologies for before—after studies as they account for regression to the mean effects. The empirical Bayes (EB) methodology examines the estimation

A numerical prediction on heat transfer characteristics from a circular tube in supercritical fluid crossflow

Studies on fluids at supercritical pressure have been developed in a rapid-growth manner so that geometries are not restricted to circular tube. This paper is devoted to conduct a brief review of the recent main experiments on supercritical fluids such as CO 2 , water, R134a and n-decane, and to comment the findings. In addition, this paper discusses the probability of supercritical fluids flowi

Magnetic storms disrupt nocturnal migratory activity in songbirds

Birds possess a magnetic sense and rely on the Earth's magnetic field for orientation during migration. However, the geomagnetic field can be altered by solar activity at relative unpredictable intervals. How birds cope with the temporal geomagnetic variations caused by solar storms during migration is still unclear. We addressed this question by reproducing the effect of a solar storm on the geom

CFD-beräkningar vid brandteknisk dimensionering - En Round Robin studie

Föreningen för Brandteknisk IngenjörsVetenskap (BIV) har genomfört en s.k. Round Robinstudie inom beräkningsområdet CFD. I studien utförde nio deltagande aktörer samma beräkningsuppgifter utan att veta vad de andra kommit fram till. Resultat-sammanställningen visar en relativt stor spridning som till största delen kan förklaras med att deltagarna gör olika ingenjörsmässiga val.De två beräkningsfal

Animated adverts impair children’s online reading and text comprehension

In this study we examined the effects of animated adverts on children’s online reading. We conducted an eye-tracking experiment with authentic web pages to assess whether (1) advert animation primarily affects overt visual attention, or (2) animated adverts primarily affect text comprehension, or (3) both eye movements and comprehension are affected. 59 children in third grade (9-year-olds) partic