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The push to reduce size, weight, power, and cost (SWaP-C) has led to the integration of multiple subsystems with different criticality levels onto a single hardware platform. Virtualization has played a crucial role in merging real-time capabilities with complex environments, facilitating the creation of Mixed-Criticality Systems (MCS). However, consolidating various workloads on a single platform often requires shared peripheral access, such as Network Interface Controllers (NICs), among guest Virtual Machines (VMs). VirtIO provides a standardized interface for device para-virtualization, enabling us to deploy device drivers and sharing logic within dedicated VMs. Despite its advantages, VirtIO can introduce latency and reduced throughput due to its reliance on the hypervisor or other VMs for network access, which may exacerbate resource contention and affect time isolation between VMs. Time-Sensitive Networking (TSN) techniques can mitigate these issues by ensuring reliable, low-latency, and deterministic network communication, although its implementation often depends on proprietary Linux-based solutions. In this paper, we present BiRtIO, an infrastructure designed to support a virtual real-time network for VMs on the Bao hypervisor without compromising safety and security. It leverages the VirtIO standard and incorporates TSN mechanisms available in mainline Linux, such as bandwidth limitation, to enhance performance and predictability in a saturated virtualized network. Experiments conducted on the Xilinx ZCU102 high-performance multicore platform demonstrate that our solution achieves performance and predictability levels suitable for real-time workloads on MCS with limited Ethernet ports.

This systematic literature review investigates the factors influencing cloud computing adoption within both educational and organizational settings. By synthesizing a comprehensive body of research, this study finds and analyzes the determinants that shape the decision-making process about cloud technology adoption. Security, cost-effectiveness, scalability, interoperability, and regulatory compliance are examined across educational institutions and organizational contexts. Additionally, socio-economic, political, and technological factors specific to each context are explored to provide a nuanced understanding of the challenges and opportunities associated with cloud computing adoption. The review reveals commonalities and differences in adoption drivers and barriers between education and organizational environments, offering insights into tailored strategies for effective implementation. This research contributes to the existing literature by shedding light on the multifaceted nature of cloud adoption and offering valuable guidance for educators, organizational leaders, policymakers, and technology providers looking to use cloud computing to enhance operations and services.

Virtualization technology has played a pivotal role in consolidating Mixed-Criticality Systems (MCS) onto a single computing platform. However, not all RISC-V processors present in Commercial Off-The-Shelf (COTS) platforms feature the so called Hypervisor extension, which poses a significant challenge in offering hardware virtualization capabilities in existing RISC-V silicon. This paper introduces HSP-V, a ready-to-run low-level software stack to provide static partitioning on RISC-V COTS platforms lacking hardware virtualization support. HSP-V leverages the Domain feature of the RISC-V Open Source Supervisor Binary Interface (OpenSBI) reference implementation to define partitions protected by the Physical Memory Protection (PMP) unit. Additionally, it provides other capabilities such as interrupt partitioning, direct interrupt injection, cache partitioning, and platform-level isolation for DMA-capable devices. The conducted evaluation assesses the impact of HSP-V on different empirical metrics, including domain boot time, interrupt latency, code size, and execution performance using micro and application benchmarks (LMBench and MiBench, respectively). HSP-V achieves highly deterministic interrupt latency with an average execution time of 457 ns (with a standard deviation of only 22 ns), with essentially zero traps in the Domain execution. In scenarios with cache interference, the HSP-V keeps the performance overhead as low as 0.39% for the best case scenario. Finally, all work described in this article is publicly available and open-sourced for the community to further evolve, port, and evaluate HSP-V in other hardware platforms.

The determination of impurities in raw materials intended for the production of pharmaceutical products is important to guarantee the quality of the final product, as well as to avoid damage to health. Metallic impurities can exhibit toxic effects even at low concentrations and so permissible levels are defined by the regulatory agencies and pharmacopeias. However, few methods are presented in official compendia in Brazil. In this sense, fast, sensitive, and precise techniques such as the energy dispersive X-ray fluorescence technique (EDXRF) must be evaluated for the analysis of metals in materials for pharmaceutical use. This way, therefore, there is the need to investigate the presence of contaminants and their concentration levels. The major goal of this research work was to validate a method for using the Energy Dispersive X-Ray Fluorescence (EDXRF) technique to identify and quantify the chemical composition of raw materials and pharmaceutical products. The methodology used was based on the selection of a microcrystalline cellulose matrix, which was spiked with two classes of contaminant elements, Class 1 (Cd, Pb, As, Hg) and Class 2A (Co, V, Ni) as defined by ICH guideline Q3D. The qualitative and quantitative analyses were carried out using the EDXRF technique, which proved to be quite effective and met all the validation parameters required in the mandatory official compendia (Resolution of the Collegiate Board (RDC) of Brazilian Health Regulatory Agency (Anvisa) nº 166, July 24, 2017), such as selectivity, linearity, precision, detection limit, quantification limit and robustness. This study showed that EDXRF can be used as a technique for detection and quantification of elemental impurities belonging to Class 1 and Class 2A.

The goal of this research was to evaluate the chemical composition of some herbal products consumed in Brazil through the Energy Dispersive X-ray Fluorescence (EDXRF). The methodology used encompassed the selection of 14 plants’ dried extracts and six ground plants. The qualitative and quantitative analyses of samples indicating the presence of As, Cr, Cu, Fe, Ni, Zn, Si, P, S, Cl, K, Ca, Ti, V, Mn, Co, Rb, Zr, Cd, Sn, Ba, Hg, Pb, Bi, Mo, and Pt in different concentrations. It is feasible that part of the contamination found in the herbal products come from the adjuvants/excipients used in the production process. Also, it was found that the extract production process seems to have a low efficiency for the extraction of the main chemical elements present in the ground plants. In the other hand, it has the benefit of reducing the contamination by harmful elements to health, such as heavy metals. EDXRF can replace atomic absorption spectrometry as low-cost and high precision technique to quantify all elements of interest in the pharmaceutical and food industries, within the limits established by regulatory agencies

O cimento Portland é o componente básico do concreto. A espectroscopia de fluorescência de raios X é uma técnica analítica estabelecida usada em fábricas de cimento em todo o mundo. Um estudo comparativo dos constituintes elementares presentes em cimentos Portland produzidos no Brasil foi realizado através da análise via EDXRF. Os principais elementos identificados e quantificados nas amostras de cimento foram Al, Ca, Fe, K, Si, S, Ti, Mn, Zn e Sr. Os principais componentes do cimento são cal (CaO), sílica (SiO2), alumina (Al2O3), óxido de ferro (Fe2O3), magnésia (MgO), álcalis (Na2O e K2O) e sulfatos (SO3). Os componentes C3S, C2S, C3A e C4AF foram calculados pela fórmula de Bogue. Foram feitas argamassa com água, cimento e areia para cada marca de cimento e foram realizadas análises para avaliar a resistência à compressão mecânica. Os corpos foram quebrados após a cura nos seguintes prazos: 1, 3, 7, 28 e 91 dias. Os resultados dos ensaios mecânicos foram correlacionados com os componentes encontrados nas diferentes marcas de cimento. Nossos resultados indicam que a resistência à compressão inicial pode variar muito de uma marca para outra e os valores para os potenciais do Bogue mostram grandes diferenças para C3S e C2S. Foi demonstrado por testes de resistência como é possível prever o comportamento das argamassas feitas com esses cimentos. Os cimentos provaram ser bons para a fabricação de argamassas e atendem às especificações Brasileiras.

Students of business administration in polytechnic higher education are faced with management content that can present specific difficulties when it refers to organisational contexts with which they are generally unfamiliar. This paper examines the way in which a learning and assessment methodology aimed at promoting "proximity" to subjects and course content can be put into practice through the use of a context that is "familiar to students": business and economics news in the media. By performing a critical analysis of a news item in the media, students select and apply the content of the course they are studying to a real event. In parallel to presenting the results obtained using the methodology concerned (student performance and mark obtained), student perception of this active methodology will also be analysed. The conclusion will focus on ways of adapting the teaching of management to students' particular interests and knowledge. (Contains 2 tables, 7 graphs, and 11 footnotes.)

Relations between higher education institutions and local companies are generally considered to be very important to the success of education provision and for the social fabric surrounding the school. This article describes a case study of bringing together two parties with an interest in the school's action: students and companies. Group work as an assessment tool for resolving a specific problem or analysing a business situation in detail, when carried out in businesses, allows learning to take place in an everyday context. This helps both students and companies to achieve their objectives--learning and academic success for the former and the exchange of knowledge with a collaborative school open to its local environment for the latter. (Contains 8 figures and 6 footnotes.)