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The loss of OH maser emission in the early stage of Post-AGB evolution

Based on the results of an on-going monitoring program of 1612 MHz OH masers in OH/IR stars, we determined a lifetime encompassing late AGB and early post-AGB evolution of at least 4500 years. Fading of the OH masers observed with the Nançay Radio Telescope is detected in several post-AGB OH/IR stars on timescales of decades, while AllWISE/NEOWISE light curves taken almost in parallel show diverse

Integrated millimeter Wave CMOS Power Amplifiers for 5G Systems

The anticipated continuation of the last three decades of growth of global demand for high-speed high-coverage mobile data, calls for massive investments in cellular infrastructure, for the ongoing roll out of the fifth generation of mobile systems, but also later for the sixth generation. A key enabler, for the high-speed part, is for the cellular system to move up in frequency and support commun

Mahalla in Uzbekistan: An Embodiment of Muslim Values of Neighbourliness and Mutual Support

The main purpose of this brief reflection is to examine the relationship between (a) Muslim communal values of neighborliness, mutual support and responsibility for those living together in a defined, spacial community and b)the built environment and structures of mosques and community gathering spaces, with a focus on how the existence of such a built environment and infrastructure helps to devel

Youth handball concussion prevention strategies: A workshop-based study with experts and end users

Sport-related concussion (SRC) is a serious injury in youth team sports, including handball. While research on the prevention of SRC has made progress over the past 5 years, prevention strategies are lacking in handball. The aim was to explore and develop strategies focusing on information, rules and training that may prevent concussion in youth handball by incorporating knowledge from experts and

Multi-fidelity reduced-order surrogate modelling

High-fidelity numerical simulations of partial differential equations (PDEs) given a restricted computational budget can significantly limit the number of parameter configurations considered and/or time window evaluated. Multi-fidelity surrogate modelling aims to leverage less accurate, lower-fidelity models that are computationally inexpensive in order to enhance predictive accuracy when high-fid

Uncertainty quantification for nonlinear solid mechanics using reduced order models with Gaussian process regression

Uncertainty quantification (UQ) tasks, such as sensitivity analysis and parameter estimation, entail a huge computational complexity when dealing with input-output maps involving the solution of nonlinear differential problems, because of the need to query expensive numerical solvers repeatedly. Projection-based reduced order models (ROMs), such as the Galerkin-reduced basis (RB) method, have been

Data-driven analysis of parametrized acoustic systems in the frequency domain

A data-driven method combined with the formulations of boundary integral equations is developed for the frequency-domain analysis of parametrized acoustic systems, arising from the spatial discretization of the linear Helmholtz equation. The method derives surrogate models for the approximation of frequency response functions at selected field points via the construction of neural networks with ra

CONTROL SYSTEM SUITE FOR BEAM POSITION MONITORS AT MAX IV

MAX IV is a fourth generation synchrotron facility at Lund, Sweden. It is composed of a full energy linear accelerator and two storage rings with 1.5 GeV and 3 GeV, which requires hundreds of beam position monitors. In this context, Libera Single Pass E and Libera Brilliance+ are employed as BPM instruments. This paper will present an overview of the control system suite used in the facility, incl

Proposed Drilling into Postglacial Faults : The Pärvie Fault System

The existence of postglacial faults (PGFs) in northern Fennoscandia was first documented in Finland in the last century. Subsequently, over a dozen large PGFs have been observed in Finland, Sweden and Norway. PGFs have been investigated through geophysical methods, trenching and mapping of brittle deformation structures. No direct measurements of the age of faulting exist, although relative ages w

A High-Speed Comparator Using a New Regeneration Latch

This paper presents a high-speed comparator which employs a novel regeneration latch to enhance the comparison process. The regeneration stage employs an innovative mechanism that reduces the RC constant at the output while avoiding static power consumption. Furthermore, the proposed comparator is capable of operating seamlessly with a rail-to-rail input common-mode voltage. This is made possible

BEAM STABILITY IN THE MAX IV 3 GeV STORAGE RING

The MAX IV Laboratory, inaugurated in 2016, hosts a 3 GeV ultra-low emittance storage ring, a 1.5 GeV storage ring and a linear accelerator driven Short Pulse Facility to deliver synchrotron radiation to scientific users. A Stability Task Force has been assigned to ensure the delivery of stable beams since early on in the design phase of the laboratory and is continuing its work in an ongoing and

An Oscillator with Inductively Coupled Resonators for Readout of Stretchable Resistive Strain Sensor

This paper proposes a wireless and stretchable sensor which uses an oscillator with an inductively coupled resonator. By delving into the malleable nature of these cutting-edge electronics, we determine the most effective circuit parameters to optimize signal behavior for specific applications. The findings showed that the simulated frequency shift sensitivity to variations in sensor resistance in