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EMERALD: Evidence Management for Continuous Certification as a Service in the Cloud
No full textPublisher Copyright: Copyright © 2025 by SCITEPRESS - Science and Technology Publications, Lda.The conspicuous lack of cloud-specific security certifications, in addition to the existing market fragmentation, hinder transparency and accountability in the provision and usage of European cloud services. Both issues ultimately reflect on the level of customers’ trustworthiness and adoption of cloud services. The upcoming demand for continuous certification has not yet been definitively addressed and it remains unclear how the level’high’ of the European Cybersecurity Certification Scheme for Cloud Services (EUCS) shall be technologically achieved. The introduction of AI in cloud services is raising the complexity of certification even further. This paper presents the EMERALD Certification-as-a-Service (CaaS) concept for continuous certification of harmonized cybersecurity schemes, like the EUCS. EMERALD CaaS aims to provide agile and lean re-certification to consumers that adhere to a defined level of security and trust in a uniform way across heterogeneous environments consisting of combinations of different resources (Cloud, Edge, IoT). Initial findings suggest that EMERALD will significantly contribute to continuous certification, boosting providers and users of cloud services to maintain regulatory compliance towards the latest and upcoming security schemes.Peer reviewe
Plasma nitrided ferritic stainless steel surfaces as hydrogen permeation barriers
Get PDFPublisher Copyright: © 2025 The AuthorsHydrogen has the potential to replace fossil fuels in certain sectors where decarbonization presents significant challenges. However, components manufactured in metallic alloys that come into contact with hydrogen are susceptible to hydrogen induced embrittlement (HE) to varying degrees. Plasma based surface treatments might provide a barrier to hydrogen diffusion, a prerequisite for HE. This study aims at investigating the performance as hydrogen diffusion barrier of active screen plasma nitrided treatments on a ferritic stainless steel (X6Cr17). The research has focused on the nitriding parameters (mainly processing temperature), as well as the thickness and microstructure of the steel. A variety of techniques, including X-ray diffraction spectroscopy, microscopy, indentation and hydrogen permeation tests were employed throughout the study on different nitrided surfaces. The findings of the study indicate that plasma nitrided surfaces act as effective hydrogen permeation barriers. Results show a reduction of the hydrogen permeation flow by up to two orders of magnitude compared to the same untreated steel alloy (2.0 × 10−9 vs. 4.2 × 10−7 Pa.m3/s). This is accompanied by a delay in the hydrogen permeation uptake of >25 times compared to the same untreated steel alloy. However, the findings also indicate that the surface treatment effectiveness is influenced by both the presence of surface defects and the depths and microstructure of the nitrided surfaces.Peer reviewe
Sustainable Building Standards in the Galapagos Islands: Definition, Simulation, and Implementation in Representative Living Labs
Get PDFPublisher Copyright: © 2025 by the authors.The Galapagos Islands are undeniably a highly attractive ecosystem for scientists worldwide. However, the energy efficiency and sustainability aspects of their building stock have not yet been studied in depth, which directly hinders the achievement of sustainability goals for the Archipelago, such as reducing resource consumption, minimizing emissions, and improving overall comfort in buildings. Addressing these issues is critical to preserving the islands’ unique ecosystem, as current construction practices are unsustainable and exacerbate environmental pressures, causing over-consumption of local resources and upsetting the delicate ecological balance that sustains this fragile environment. In line with the National Energy Efficiency Plan promoted by the Government of Ecuador for the Archipelago, this study provides transparent and reliable information and data on the building stock of the islands. This work quantifies the impact of buildings on the use of resources and analyses the potential savings of different strategies for reducing greenhouse gas emissions. Various representative typologies are established based on the collection of architectural, construction, and usage information. For each of these typologies, various energy models are developed to establish the baseline and to analyse the demand and comfort of the buildings under different renovation scenarios in order to validate the sustainable construction strategies to be implemented. Moreover, new standards are also defined in order to reduce energy and water consumption and increase indoor air quality and comfort in buildings. In an attempt to generate evidence and facilitate the replication and implementation of sustainable construction standards, three Living Labs (LLs) are created to validate different strategies and technological solutions in different locations, according to the defined standards: a school in Santa Cruz, a hotel in Isabela, and a residential building in San Cristóbal. The findings highlight the effectiveness of specific energy-saving strategies and water conservation measures validated through Living Labs implemented in different locations across the islands. Furthermore, the knowledge generated is transferred through local training of the agents of the construction chain and administration.Peer reviewe
Comprehensive prospective environmental assessment of innovative photovoltaic technologies: Integration into electricity grids in Finland, Germany, and Spain
Get PDFPublisher Copyright: © 2025This study evaluates the environmental performance of advanced solar photovoltaic technologies, including floating, bifacial ground-mounted, and building-integrated photovoltaics systems, compared to conventional technologies in Finland, Germany and Spain from 2022 to 2050. A novel aspect of this research is the integration of multiple photovoltaics technologies, time horizons (2022, 2030, and 2050), and climatic zones, providing a more complete understanding of their lifecycle impacts. The study uses a prospective life cycle assessment approach, offering scenario-based projections to assess future environmental impacts under changing energy mixes and climatic conditions. The results highlight the critical role of local solar irradiation, as seen in the higher carbon footprint of floating photovoltaic systems in Murcia (30.2 gCO2/kWh, 2022) than in Lappeenranta (15.7 gCO2/kWh). Over time, environmental impacts decrease significantly; floating photovoltaics in Murcia reduces to 17.5 gCO2/kWh in 2050, and bifacial systems drop from to 14.9 gCO2/kWh. Overall, bifacial systems have the lowest environmental impact, followed by floating photovoltaics, while building-integrated systems show the highest impact. The findings highlight the critical importance of transitioning to renewable energy in electricity grids to reduce environmental impacts, while emphasizing the role of location-specific factors, technological advancements, and evolving energy systems in shaping the environmental performance of photovoltaics technologies.Peer reviewe
Hydrogen Station Model Design Using Functional Mock-Up Units and Metaheuristics Optimization
No full textPublisher Copyright: © The Author(s) 2025.Hydrogen-powered heavy-duty vehicles will transform the logistics landscape, but their extensive adoption presents substantial challenges. Matching hydrogen demand with supply, scaling up infrastructure, controlling carbon emissions targets, and integrating with renewable energy sources are significant obstacles to overcome. This paper addresses these challenges by modeling a hydrogen station for heavy-duty vehicle fleets using Matlab-Simulink software. The hydrogen station components proposed are individually modeled: (1) the electrolyzer model generates hydrogen and oxygen by electrolysis consuming water and electricity; (2) the hydrogen reformer model generates hydrogen and carbon dioxide through steam methane reforming or ethanol reforming; (3) the hydrogen storage tank; and (4) carbon capture and storage. These models were compiled into functional mock-up units (FMU) to facilitate further exploration. This paper incorporates metaheuristic optimization techniques to address the design complexities and enhance the performance of hydrogen stations under various operating conditions. Multiple optimization objectives have been considered, including reducing carbon emissions and reducing the total monetary cost. Furthermore, several critical constraints are integrated to ensure realistic scenarios. These constraints include the accumulated hydrogen production that meets daily demand and the limitations in resource consumption. Finally, the combination of the FMU approach with metaheuristics techniques demonstrates the potential for the optimal hydrogen infrastructure design.Peer reviewe
Transfer of knowledge through reverse annealing: a preliminary analysis of the benefits and what to share
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Detecting Scam Tokens and Backdoor Functions in EVM Based Networks
No full textPublisher Copyright: © The Author(s), under exclusive license to Springer Nature Switzerland AG 2025.The blockchain ecosystem is currently becoming an intricate landscape given the large number of attacks, scams, and hacks that occur. With such risk surrounding Blockchain DApps and users, we propose a method to help in the earlier detection of scam tokens. While blockchain technology continues to grow in multiple industries, the proliferation of fraudulent activities in the decentralized ecosystem has become a significant threat to the well-being and trustworthiness of the whole ecosystem. This scam tokens are deployed in plain sight in decentralized networks and listed in platforms such as CoinMarketCap and other token issuance platforms. In this paper, we identify over 1450 unreported scam tokens, 167 different backdoor functions, and 1428 malicious contract creators. By increasing the collaboration between industry stakeholders and web3 companies, our scam tokens dataset and detection tools can help in web3 threat detection while creating a more secure and resilient blockchain environment, fostering trust and innovation in the decentralized space.Peer reviewe
Flame Spread on an Active Photovoltaic–Roof System
Get PDFPublisher Copyright: © 2025 by the authors.Solar photovoltaic (PV) systems in buildings must comply with both electrotechnical standards for module safety and local building codes, which typically do not address their electrical nature. This regulatory gap creates challenges in assessing the fire performance of PV systems. This paper presents a procedure to adapt a common test method used in some building codes to assess external fire conditions for roofs, while maintaining operative PV modules. Two configurations were tested: an organic PV thin film on a metallic sandwich panel and a glass–glass-encapsulated organic PV module. The tests were conducted under high voltage and current conditions to simulate the systems’ behavior within a larger PV array. Significant electric arcs were observed during testing of the metallic sandwich panel configuration without glass protection when subjected to high voltages or currents. In these cases, total heat release increased by at least 30% compared to non-electrically loaded scenarios or glass-insulated PV modules, likely due to a greater damaged surface area. Electric arcs created new ignition sources, damaging whole PV modules, whereas in the case with no electrical load, propagation flames advanced toward both the upper edge and the corners of the sample, ultimately damaging the entire triangular area above the fire source. The results indicate that the electrical characteristics of PV systems can significantly impact external fire spread behavior. The study identifies challenges in maintaining system activity during testing and simulating real scenarios and proposes for future research directions.Peer reviewe
Foaming and cross-linking of cellulose fibers using phytic acid
Get PDFPublisher Copyright: © 2024 The Author(s)Bio-based compounds have become the focus in the development of next-generation materials. The polyphosphated structure and availability of phytic acid has sparked an interest to understand its properties and apply it to making fire-retardant fabrics. However, its degradative effect on natural fibers sets limitations to its potential uses. In this study, we unveiled a new dimension to explore with phytic acid: cellulose fiber foams. Phytic acid enabled synergistic foaming with carboxymethyl cellulose albeit causing issues in long-term wet foam stability. Adding cellulose fibers to this mixture and drying at 160 °C produced solid foams with increased compressive strength and stiffness; comparable to foams cross-linked with the commonly used citric acid. The reduced contact area in low-density fiber networks allowed the cross-linking between phytic acid and the fiber network to mitigate structural weakening due to fiber degradation. Imaging also revealed the formation of a film encompassing fiber bonds; attributed to the strong interaction between phytic acid and carboxymethyl cellulose. Furthermore, phytic acid imparted self-extinguishing fire-retardant properties to the cellulose fiber foams measured using thermogravimetric analysis and cone calorimetry. This work showcases a simple new application for phytic acid without the use of catalysts or solvents. It serves to encourage further development of green practices to continuously challenge the industrial landscape.Peer reviewe
Prediction of Wear Rate by a New Direct Method Using the Friction Coefficient Curve
Get PDFPublisher Copyright: © 2024 by the authors.This work aims to introduce a new method to predict the wear rate accurately and quickly. Using techniques such as laser scanning confocal microscopy can take a long time to estimate the wear of the experimental alloys in situ. Developing a new method based on calculating the area under the early stages of the friction curve can be a useful and quick tool for estimating wear rate values and comparing wear between different alloys and conditions. The results validated the application of this new method with a regression coefficient of 0.98. This work also demonstrates that wear in the early stages accounts for the highest wear, indicating that the friction coefficient in the steady-state is not always a reliable indicator of the total wear rate. Hardness can be a more influencing parameter on wear rate than steady-state friction coefficient. Using the new method can help reduce time and predict wear more accurately of different alloys.Peer reviewe