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Spherical Large Intelligent Surfaces

As an emerging technology and evolution that goes beyond massive multi-input multi-output (MIMO), large intelligent surface (LIS) has gained much interest. LIS acts as an electromagnetic surface that can transmit, redirect, and receive radiating signals across its entire contiguous surface. It allows for unprecedented energy-focusing, data-transmission and terminal-positioning, and can fulfill the

Safety and health effects in high and ultra-high field MR

Background: More than 70 million magnetic resonance (MR) examinations are produced every year. Patients and personnel are exposed to electromagnetic fields at levels that exceed those normally found in our surroundings or in industry. Three types of electromagnetic field exposure must be considered in regard to MR safety: the strong force of the static magnetic field, the time-varying gradient mag

Optimal Measurement Projections with Adaptive Mixture Kalman Filtering for GNSS Positioning

Accurate carrier-phase integer ambiguity resolu-tion is fundamental for high precision global navigation satellitesystems (GNSSs). In this paper we extend a recently proposedmixture Kalman filter solution to integer ambiguity resolution.We utilize the Fisher information matrix to project the acquiredmeasurements into a lower-dimensional subspace, formulatingan optimization program to find the proj

Do Preparatory Programming Lab Sessions Contribute to Even Work Distribution in Student Teams?

Unfair work distribution is common in project-based learning with teams of students. One contributing factor is that students are differently skilled developers. To mitigate the differences in a course with group work, we introduced mandatory programming lab sessions. The intervention did not affect the work distribution, showing that more is needed to balance the workload. Contrary to our goal, t

Upgrade Methods for Stratified Sensor Network Self-Calibration

Estimating receiver and sender positions is often solved using a stratified, two-tiered approach. In the first step the problem is converted to a low-rank matrix estimation problem. The second step can be seen as an affine upgrade. This affine upgrade is the focus of this paper. In the paper new efficient algorithms for solving for the upgrade parameters using minimal data are presented. It is als

On Harmonic Approximations of Inharmonic Signals

In this work, we present the misspecified Gaussian Cramér-Rao lower bound for the parameters of a harmonic signal, or pitch, when signal measurements are collected from an almost, but not quite, harmonic model. For the asymptotic case of large sample sizes, we present a closed-form expression for the bound corresponding to the pseduo-true fundamental frequency. Using simulation studies, it is show

Quality of life of ice hockey players after retirement due to concussions

Background: Sports-related concussion (SRC) is increasingly recognized as a potential health problem in ice hockey. Quality of life (QoL) in players retiring due to SRC has not been thoroughly addressed. Materials & methods: QoL using the Sports Concussion Assessment Tool 5th Edition, Impact of Event Scale-Revised and Short Form Health Survey was measured in Swedish ice hockey players who reti

Robust Fundamental Frequency Estimation in Coloured Noise

Most parametric fundamental frequency estimators make the implicit assumption that any corrupting noise is additive, white Gaus-sian. Under this assumption, the maximum likelihood (ML) and the least squares estimators are the same, and statistically efficient. However, in the coloured noise case, the estimators differ, and the spectral shape of the corrupting noise should be taken into account. To

On Statistical Properties of the Gamow–Teller Strength Distribution in 60 Ca

Abstract: The β-decay half-life and the delayed neutron emission of 60Ca are studied within a microscopic model, which is based on the Skyrme interaction T45 to construct single-particle and phonon spaces. We observe a redistribution of the Gamow–Teller strength due to the phonon-phonon coupling and the tensor correlations, considered in the model. For 60Sc, the spin-parity of the ground state is