Finite element analysis of the Girkmann problem using the modern hp-version and the classical h-version

We perform finite element analysis of the so called Girkmann problem in structural mechanics. The problem involves an axially symmetric spherical shell stiffened with a foot ring and is approached (1) by using the axisymmetric formulation of linear elasticity theory and (2) by using a dimensionally reduced shell-ring model. In the first approach the problem is solved with a fully automatic hp-adaptive finite element solver whereas the classical h-version of the finite element method is used in the second approach. We study the convergence behaviour of the different numerical models and show that accurate stress resultants can be obtained with both models by using effective post-processing formulas.     

Physical layer enhancements in 5G-NR for direct access via satellite systems

Among the several features and capabilities introduced by every new 3GPP release on 5G cellular systems, the latest Release 17 will be remembered as the first that specifies a set of enhancements and adaptations to support mobile broadband services via satellite direct access. Specifically focused on the necessary physical layer mechanism and procedure modifications, this paper will present in detail the 3GPP work about the inclusion of satellite systems in 5G networks.     

A 3-D hp finite/infinite element method to calculate power deposition in the human head

The electromagnetic power deposition and transfer properties of a G1 continuous head model reconstructed from magnetic resonance imaging (MRI) data are investigated by using the coupled hp finite/infinite element (FE/IE) method. The discretization error is controlled by a self-adaptive process driven by an explicit a posteriori error estimate. Based on the benchmark problem of reproducing the Mie series solution, the scattering of a plane wave on the curvilinear head model is used to evaluate the hp FE/IE approach and calibrate the error bound. The radiation pattern from a short dipole antenna modeling a cell phone, is analyzed in terms of the level and distribution of the specific absorption rates (SAR). The numerical experiments show that the hybrid hp FE/IE implementation is a competitive tool for accurate assessment of human electromagnetic exposure.     

Trichlorosilanes as Anchoring Groups for Phenylene‐Thiophene Molecular Monolayer Field Effect Transistors

Self assembled monolayer field effect transistors (SAMFETs) are reported using a phenylene‐thiophene containing semiconducting mesogen attached through a trichlorosilane anchoring group. Monolayer films, covalently attached to silicon dioxide substrates, form in less than 10 h from solution, thanks to the accelerated reaction of the trichlorosilane anchor. Devices exhibit mobilities as high as 1.7 × 10^?2 cm² V^?1 s^?1, currents of up to 15 μA (on/off current ratio of 10⁶) with device yields close to unity over large areas for channel lengths up to 100 μm.     

PADLOC: a powerful tool to assign disulfide bond connectivities in peptides and proteins by NMR spectroscopy

The determination of the disulfide bond connectivity in a peptide or protein represents a significant challenge. It is notoriously difficult to use NMR spectroscopy to assign disulfide connectivities because NMR spectra lack direct evidence for disulfide bonds. These bonds are typically inferred from three-dimensional structure calculations, which can result in ambiguous disulfide assignment. Here, we present a new NMR based methodology, in which the disulfide connectivity is obtained by applying Bayesian rules of inference to the local topology of cysteine residues. We illustrate how this approach successfully predicts the disulfide connectivity in proteins for which crystal structures are available in the protein data bank (PDB). We also demonstrate how this methodology is used with experimental NMR data for peptides with complex disulfide topologies, including hepcidin, Kalata-B1, and μ-Conotoxin KIIIA. In the case of μ-Conotoxin KIIIA, the PADLOC connectivity (1-15,2-9,4-16) differs from previously published results; additional evidence is presented demonstrating unequivocally that this newly proposed connectivity is correct.     

Application of neural networks for the prediction of continuous cooling transformation diagrams

In the paper the method of forecasting of Continuous Cooling Transformation (CCT) diagrams for steels by the use of neural networks has been presented. Input data are chemical composition and austenitising temperature. Results of calculation of neural networks consist of temperature of the beginning and the end of transformation in the function of cooling rate, the participation of the structural components and the hardness of steel cooled from austenitising temperature with a fixed rate. Presented quantities enable to draw the CCT diagram. The model presented in the paper enables the analysis of the influence of the chemical composition and austenitising temperature on CCT diagrams. In order to work out the methods, the set of experimental data worked out on the basis of information available in the literature consisting of 400 CCT diagrams made for constructional and machinable steels were used.     

XAFS study of europium chloride at high temperatures

Local structural changes in europium dichloride around europium ion at high temperature are evaluated by using X-ray absorption fine structure technique. A distinct phase shift in EXAFS oscillation observed between 700 and 950K arises from Eu²⁺ to Eu³⁺ oxidation. Referring to the difference in EXAFS oscillation between oxide and oxychloride of lanthanum, the chemical state of europium on oxidation is identified mainly as Eu₂O₃.