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Highlights: The boosted heterogeneous interfaces in titanium nitride (TiN) nanotube/polydimethylsiloxane (PDMS) composite contributed to strong polarization loss relaxation ability. The TiN nanotubes/PDMS composite possessed both good impedance matching behavior and strong dielectric loss ability in wide temperature spectrum. The TiN nanotubes/PDMS composite exhibited excellent EMWA performances (effective absorption bandwidth value of 3.23 GHz and minimum reflection loss value of − 44.15 dB) at the varied temperature from 298 to 573 K. Currently, the microwave absorbers usually suffer dreadful electromagnetic wave absorption (EMWA) performance damping at elevated temperature due to impedance mismatching induced by increased conduction loss. Consequently, the development of high-performance EMWA materials with good impedance matching and strong loss ability in wide temperature spectrum has emerged as a top priority. Herein, due to the high melting point, good electrical conductivity, excellent environmental stability, EM coupling effect, and abundant interfaces of titanium nitride (TiN) nanotubes, they were designed based on the controlling kinetic diffusion procedure and Ostwald ripening process. Benefiting from boosted heterogeneous interfaces between TiN nanotubes and polydimethylsiloxane (PDMS), enhanced polarization loss relaxations were created, which could not only improve the depletion efficiency of EMWA, but also contribute to the optimized impedance matching at elevated temperature. Therefore, the TiN nanotubes/PDMS composite showed excellent EMWA performances at varied temperature (298–573 K), while achieved an effective absorption bandwidth (EAB) value of 3.23 GHz and a minimum reflection loss (RLmin) value of − 44.15 dB at 423 K. This study not only clarifies the relationship between dielectric loss capacity (conduction loss and polarization loss) and temperature, but also breaks new ground for EM absorbers in wide temperature spectrum based on interface engineering. [ABSTRACT FROM AUTHOR]

Advanced composites with superior wave attenuation or vibration isolation capacity are in high demand in engineering practice. In this study, we develop the hybrid dynamic shear-lag model with Bloch's theorem to investigate the hybrid effect of reinforcement on wave attenuation in bioinspired staggered composites. We present for the first time the relationship between macroscopic wave filtering and hybridization of building blocks in staggered composites. Viscoelasticity was taken into account for both reinforcement and matrix to reflect the damping effect on wave transmission. Our findings indicate that reinforcement hybridization significantly enhances wave attenuation performance through two critical parameters: the linear stiffness and linear density of reinforcements. For purely elastic constituents, reinforcement hybridization consistently improves wave attenuation by reducing the initial frequency of the first bandgap and broadening it. For viscoelastic constituents, increasing the heterogeneity of reinforcements can benefit wave attenuation, particularly in ultralow frequency regimes, due to the strengthening of the damping effect. Our case study demonstrates that controlling the difference in linear density can result in up to a 59 % reduction in energy transmission. Our analysis suggests that hybridizing reinforcements could provide a new approach to designing and synthesizing advanced composites with exceptional wave attenuation performance., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

In this paper, a polarization-independent chain Huygens' metasurface is proposed. It is polarization multiplexing of two chain structures. Owing to the polarization-independent property, it can be conveniently applied to design double-layer dual-polarized transmitarray antennas (TAAs) with low profile. The measured results show that, for the designed low-profile dual-polarized TAA, its peak gain is 29.7 dBi at 28 GHz with aperture efficiency of 48.9 %, and the 3-dB gain bandwidths is 8.8 %. With the F/D ratio of only 0.36, the proposed low-profile dual-polarized TAA based on the chain Huygens' metasurface has critical applications in antenna engineering. [ABSTRACT FROM AUTHOR]

This study shows the link between computer science and applied mathematics. It conducts a dynamics investigation of new root solvers using computer tools and develops a new family of single-step simple root-finding methods. The convergence order of the proposed family of iterative methods is two, according to the convergence analysis carried out using symbolic computation in the computer algebra system CAS-Maple 18. Without further evaluations of a given nonlinear function and its derivatives, a very rapid convergence rate is achieved, demonstrating the remarkable computing efficiency of the novel technique. To determine the simple roots of nonlinear equations, this paper discusses the dynamic analysis of one-parameter families using symbolic computation, computer animation, and multi-precision arithmetic. To choose the best parametric value used in iterative schemes, it implements the parametric and dynamical plane technique using CAS-MATLAB@R2011b. The dynamic evaluation of the methods is also presented utilizing basins of attraction to analyze their convergence behavior. Aside from visualizing iterative processes, this method illustrates not only iterative processes but also gives useful information regarding the convergence of the numerical scheme based on initial guessed values. Some nonlinear problems that arise in science and engineering are used to demonstrate the performance and efficiency of the newly developed method compared to the existing method in the literature. [ABSTRACT FROM AUTHOR]

A newly invented structure called Multi-Fin-based FinFET (M-FinFET) device is a promising candidate for future improvisation of the semiconductor industry. In this article, Multi-channel FinFET (Mch-FinFET) is proposed. A comparative investigation of various DC, analog/linearity attributes is studied for gate length variation and oxide thickness through a Sentaurus TCAD tool. The simulation study concluded that the increased number of channels (= 3no.) has enhanced ION by 409.71% compared to single-channel FinFET. The decreased value of Fin width and Fin height has shown an impressive improvement of sub-threshold swing (SS) and leakage current, which helps achieve a better switching ratio. Mch-FinFET device with lower oxide thickness (Tox=1 nm) enhances the transconductance (Gm), drain conductance (Gd), intrinsic gain (Av), and transconductance gain factor (TGF) by 52.42%, 41.17%, 85.03%, respectively. Various linearity parameters like higher-order harmonics (Gm2 and Gm3), voltage intercepts points (VIP2 and VIP3), and 1-dB compression point has improved by 32.32%, 110.71% 77%, 60.09%, 418.86%, 411.5% respectively gate length of 10 nm. Besides that, a symmetric dual spacer material is introduced to the proposed structure to analyze the importance of spacer engineering. The simulation study reveals that the Mch-FinFET device with HfO2 spacer has improved driving current by 21.42%. The optimization of various short channel effects (SCEs) such as threshold voltage roll-off, sub-threshold swing (SS), and leakage current is reflected in introducing HfO2 spacer material. This detailed study is expected to design low-power RF circuits that would benefit future CMOS technology. [ABSTRACT FROM AUTHOR]

This paper presents and evaluates a role-play simulation called 'Theatrical Technology Assessment', in which students learn about complex stakeholder dynamics around emerging technologies. This role-play combines insights from Constructive Technology Assessment, improvisational theatre and educational role-play designs. It was implemented in an online setting with bachelor students of an interdisciplinary engineering programme. Based on collected chat conversations and reflection reports in seven different simulations, we qualitatively analysed what students learned about stakeholder dynamics. The study shows that students gained novel and relevant insights regarding stakeholder perspectives on technologies, the effects of uncertainties on decision making, collective stakeholder dynamics, and strategies to steer technology development. Students considered the role-play simulations to be engaging learning experiences. The dual set-up of the role-play, with students as players and co-designers, and the integral use of improvisational theatre are novel elements of educational role-play designs. [ABSTRACT FROM AUTHOR]