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Abstract Achieving precise spectral and temporal light manipulation at the nanoscale remains a critical challenge in nanophotonics. While photonic bound states in the continuum (BICs) have emerged as a powerful means of controlling light, their reliance on geometrical symmetry breaking for obtaining tailored resonances makes them highly susceptible to fabrication imperfections, and their generally fixed asymmetry factor fundamentally limits applications in reconfigurable metasurfaces. Here, we introduce the concept of environmental symmetry breaking by embedding identical resonators into a surrounding medium with carefully placed regions of contrasting refractive indexes, activating permittivity-driven quasi-BIC resonances (ε-qBICs) without altering the underlying resonator geometry and unlocking an additional degree of freedom for light manipulation through active tuning of the surrounding dielectric environment. We demonstrate this concept by integrating polyaniline (PANI), an electro-optically active polymer, to achieve electrically reconfigurable ε-qBICs. This integration not only demonstrates rapid switching speeds and exceptional durability but also boosts the system’s optical response to environmental perturbations. Our strategy significantly expands the capabilities of resonant light manipulation through permittivity modulation, opening avenues for on-chip optical devices, advanced sensing, and beyond.

With digital ecosystems being questioned around the world, this paper examines the EU’s role in and contribution to the emerging concept of artificial intelligence (AI) governance. Seen by the EU as the key ingredient for innovation, the adoption of AI systems has altered our understanding of governance. Framing AI as an autonomous digital technology embedded in social structures, this paper argues that EU citizens' trust in AI can be increased if the innovation it entails is grounded in a fundamental rights-based approach. This is assessed based on the work of the High-Level Expert Group on AI (which has developed a framework for trustworthy AI) and the European Commission’s recently approved proposal for an Artificial Intelligence Act (taking a risk-based approach).

The article is devoted to a research of an effectiveness of high-level synthesis approach, based on Xilinx's high-level synthesis tool - Vivado, for a hardware implementation of sorting algorithms, which are one of the key algorithm for Big Data analysis, Data Mining, Data Storage and Management. Performance and hardware costs are the measures of the effectiveness in the provided research. The research methods are simulation and comparative analysis. Effectiveness of software implementation of the selected sorting algorithms based on a universal processor is compared with effectiveness of hardware implementation of the same sorting algorithms, obtained by high-level synthesis procedure with help of Xilinxs synthesis tool. The article discusses approaches to optimize the description of the sorting algorithms and assignments in boundaries of high-level synthesis procedure to achieve optimal effectiveness of the final hardware solutions. The article shows that the main effectiveness gain is provided by: the internal features of the sorting algorithm, selected for hardware implementation; the ability to parallelize the processing of the source arrays, which is achieved both by the settings of the Vivado synthesis tool and description style used for source code. Article summarizes research results and provide a direction for the future research works.

Massive multi-core processing has recently attracted significant attention from the research community as one of the feasible solutions to satisfy constantly growing performance demands. However, this evolution path is nowadays hampered by the complexity and limited scalability of bus-oriented intra-chip communications infrastructure. The latest advantages of terahertz (THz) band wireless communications providing extraordinary capacity at the air interface offer a promising alternative to conventional wired solutions for intra-chip communications. Still, to invest resources in this field manufacturers need a clear vision of what are the performance and scalability gains of wireless intra-chip communications. Using the comprehensive hybrid methodology combining THz ray-tracing, direct CPU traffic measurements, and cycle-accurate CPU simulations, we perform the scalability study of x86 CPU design that is backward compatible with the current x86 architecture. We show that preserving the current cache coherence protocols mapped into the star wireless communications topology that allows for tight centralized medium access control a few hundreds of active cores can be efficiently supported without any notable changes in the x86 CPU logic. This important outcome allows for incremental development, where THz-assisted x86 CPU with a few dozens of cores can serve as an intermediate solution, while the truly massive multi-core system with broadcast-enabled medium access and enhanced cache coherence protocols can be an ultimate goal.

Concept of Monoverse, which corresponds to the existing broad interpretation of the second postulate of the special theory of relativity, is not consistent with the modern astrophysical reality — existence of the dark matter and the dark energy, the total mass-energy of which is ten times greater than the mass-energy of the visible universe (which has been considered as the entire universe until very recent) . This concept does not allow to explain their rather unusual properties — invisibility and lack of baryon content — which would seem to even destroy the very modern understanding of the term ‘matter’. However, all numerous alternative concepts of Multiverses, which have been proposed until today, are unable to explain these properties of the dark matter and dark energy. This article describes a new concept: the concept of the hidden Multiverse and hidden Supermultiverse, which mutual invisibility of parallel universes is explained by the physical reality of imaginary numbers. This concept completely explains the phenomenon of the dark matter and the dark energy. Moreover, it is shown that the dark matter and the dark energy are the experimental evidence for the existence of the hidden Multiverse. Described structure of the hidden Multiverse is fully consistent with the data obtained by the space stations WMAP and Planck. An extremely important property of the hidden Multiverse is an actual possibility of its permeation through stargate located on the Earth.

The general-purpose networks-on-chip (GP-NoC) has recently attracted the attention of the research and industry as a way to support the growing demands of computing systems. The design and the development of the communications and networking functions for such a large-scale versatile systems require knowledge of the traffic exchanged between the computing nodes. The object of the study in this paper is the last-level shared cache interface that is likely to be a traffic bottleneck in future GP-NoC architectures. First, using the direct measurements, we report on the stochastic traffic properties at large-scales, provide first two moments and distribution functions. Complementing measurements with fine-grained cycle-accurate CPU simulations, we then analyze the small-scale traffic behavior. We show that even for the simplest applications such as reading or writing of data, the nature of the traffic is stochastic, depends on the number of active cores, and irrespective of the application type, has an explicit batch structure. We further reveal that the batch sizes and inter-batch intervals can be well approximated by geometric distribution and the approximation becomes better when the number of active cores increases. These properties identify a simple arrival model that can be used in the analytical or simulation-based performance evaluation studies of the shared interface technologies in prospective NoCs.

Modern molecular electronic transfer (MET) angular motion sensors combine high technical characteristics with low cost. Self-noise is one of the key characteristics which determine applications for MET sensors. However, until the present there has not been a model describing the sensor noise in the complete operating frequency range. The present work reports the results of an experimental study of the self-noise level of such sensors in the frequency range of 0.01–200 Hz. Based on the experimental data, a theoretical model is developed. According to the model, self-noise is conditioned by thermal hydrodynamic fluctuations of the operating fluid flow in the frequency range of 0.01–2 Hz. At the frequency range of 2–100 Hz, the noise power spectral density has a specific inversely proportional dependence of the power spectral density on the frequency that could be attributed to convective processes. In the high frequency range of 100–200 Hz, the noise is conditioned by the voltage noise of the electronics module input stage operational amplifiers and is heavily reliant to the sensor electrical impedance. The presented results allow a deeper understanding of the molecular electronic sensor noise nature to suggest the ways to reduce it.

Design of command and data handling subsystems for small satellites is in the focus for many in space industry and academia. For today a plenty of small satellites have been designed, manufactured and launched. However, while the application calls for the highly standardized platform, an overview of the projects shows a vast diversity of different hardware solutions on the market. The aim of this paper is to explore the possibilities of platform-based design for the task. A Universal Module for Managing the Information is presented to be a basic node for an onboard network that comprises a command and data handling subsystem of a spacecraft bus.

Molecular-electronic transducers (MET) have a high conversion coefficient and low power consumption, and do not require precision mechanical components thus allowing the construction of cost- and power-efficient seismic accelerometers. Whereas the instrumental resolution of a MET accelerometer within the 0.1–100 Hz frequency range surpasses that of the best Micro-Electro Mechanical Systems (MEMS) and even some force-balanced accelerometers, the fundamental inability to register gravity or, in other words, zero frequency acceleration, significantly constrains the further spread of MET-based accelerometers. Ways of obviating this inherent zero frequency insensitivity within MET technology have so far, not been found. This article explores a possible approach to the construction of a hybrid seismic accelerometer combining the superb performance of a MET sensor in the middle and high frequency range with a conventional on chip MEMS accelerometer covering the lower frequencies and gravity. Though the frequency separation of a signal is widely used in various applications, the opposite task, i.e., the combining of two signals with different bandwidths is less common. Based on theoretical research and the analysis of actual sensors’ performance, the authors determined optimal parameters for building a hybrid sensor. Description and results for implementation of the hybrid sensor are given in the Experimental section of the article. Completing a MET sensor with a cost-effective MEMS permitted the construction of a low noise DC accelerometer preserving the noise performance of a MET sensing element. The work presented herein may prove useful in designing other combined sensors based on different technologies.

X-ray graphite optics consists of thin layers of Pyrolytic Graphite (PG) attached to a substrate of focusing shape. Pyrolytic Graphite is a perfect artificial graphite obtained by annealing of carbon deposit at temperatures about 3000 °C under deformation. By varying the annealing conditions, one could get PG of different mosaic structure and mechanical properties. A wide variability of the reflecting layer characteristics and optics shape makes the graphite optics useful in an extended range of applications. The optics could be adjusted to applications that require moderate resolution as EDXRF (energy dispersive X-Ray fluorescence) and as well as for high-resolution applications as EXAFS (extended X-ray absorption fine structure), XANES (X-ray absorption near-edge structure) and XES (X-ray emission spectroscopy). To realize the optics with theoretically optimized parameters the relationship between the production procedure and the mosaicity and reflectivity of the optics was experimentally studied. The influence of thickness, the type of PG (Highly Oriented PG (HOPG) or Highly Annealed PG (HAPG)) and substrate characteristics on the optics performance is presented.

In this study, the size of molten pool and the porosity of parts under different processing parameters are studied using numerical simulation. According to the results, the appropriate processing parameters were selected to simulate the temperature and residual stress distribution during the forming process of body-centered cube (BCC), face-centered cube (FCC) and rhombic dodecahedron (Dode) lattice structures. In addition, three lattice structures were fabricated via selective laser melting (SLM) technology, and quasi-static compression experiments were carried out to study their mechanical properties. The results show that the high temperature parts of the three structures are all under the node and their adjacent pillars, and the closer to the nodes, the higher the temperature. The residual stress of the Dode structure is the highest, reaching 1218.2 MPa. It is also found that the residual stress in the Z direction is the largest, which plays a dominant role in the forming process. Through compression experiments, it is found that diagonal shear failure occurs in all three lattice structures, and Dode shows the best compression performance. [ABSTRACT FROM AUTHOR]