10784 research outputs found
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Flexible Constraint-Based Controller Framework for Ros_Control
Full text linkPublisher Copyright: © 2025 by the authors.Generating robot behaviors in dynamic real-world situations generally requires the programming of multiple, often redundant degrees of freedom to meet multiple goals governing the desired motions. In this work, we propose a constraint-based controller specification methodology. A novel declarative language is used to combine semantically specialized building blocks into composite controllers. This description is automatically transformed at runtime into an executable form, which can automatically leverage multiple threads to parallelize computations whenever possible. Enabling runtime definition of controller topologies out of declarative descriptions not only reduces the work required to develop such controllers, but it also allows one to dynamically synthesize new controllers based on higher-level task planners or by user interaction through Graphical User Interfaces (GUIs). Our solution adds new functionality to the Robot Operating System (ROS)/ros_control ecosystem, where robot behaviors are typically achieved by deploying single-objective, off-the-shelf controllers for tasks like following joint trajectories, executing interpolated point-to-point motions in Cartesian space, or for basic compliant behaviors. Our proposed constraint-based framework enhances ros_control by providing the means to easily construct composite controllers from existing primary elements using our design language. Building on top of the ros_control infrastructure facilitates the usage of our controller with a wide range of supported robots and enables quick integration with the existing ROS ecosystem.Peer reviewe
Prioritising Critical Factors for Local Economic Development in Urban Regeneration Strategies
Full text linkPublisher Copyright: © 2025 by the authors.Local economic development (LED) strategies at the district level—such as sub-city or neighbourhood initiatives—play a crucial role in fostering sustainable and inclusive urban growth. This study explores the critical factors influencing LED and urban regeneration at the district scale, emphasising the integration of sustainability, digital technologies, inclusivity, energy efficiency, community engagement, and innovation into strategic planning. To prioritise these CFs, a tailored survey was distributed among a group of 13 city experts from European cities, involved in research projects focused on district-level quality-of-life enhancements through building retrofits, urban space interventions, energy community promotion, and technological deployment. By focusing on the district level, this research highlights the importance of tailoring strategies to local contexts and leveraging the unique characteristics of each neighbourhood. The findings reveal the need for local governments to enhance the capacity of administrative staff to engage citizens and direct external support for development projects. The normative recommendations derived from this study are specifically grounded in district-level research and practice, ensuring their applicability to sub-city areas. This paper concludes that a context-specific and collaborative approach is essential for achieving equitable and sustainable economic development at the district level.Peer reviewe
Hydrogen Evolution Reaction of Electrodeposited Ni-W Films in Acidic Medium and Performance Optimization Using Machine Learning
No full textPublisher Copyright: © 2024 The Authors. ChemSusChem published by Wiley-VCH GmbH.Ni−W alloy films were electrodeposited from a gluconate aqueous bath at pH=5.0, at varying current densities and temperatures. While there is little to no difference in composition, i. e., all films possess ~12 at.% W, their activity at hydrogen evolution reaction (HER) in acidic medium is greatly influenced by differences in surface morphology. The kinetics of HER in 0.5 M H2SO4 indicates that the best performing film was obtained at a current density of −4.8 mA/cm2 and 50 °C. The Tafel slopes (b) and the overpotentials at a geometric current density of −10 mA/cm2 (η10) obtained for 200 cycles of linear sweep voltammetry (LSV) from a set of films deposited using different parameters were fed into a machine learning algorithm to predict optimum deposition conditions to minimize b, η10, and the degradation of samples over time. The optimum deposition conditions predicted by the machine learning model led to the electrodeposition of Ni−W films with superior performance, exhibiting b of 33–45 mV/dec and an η10 of 0.09–0.10 V after 200 LSVs.Peer reviewe
Heritage valorisation as a means of rural regeneration: the RURITAGE inventory of Lessons Learnt
No full textPublisher Copyright: © 2025, Emerald Publishing Limited.Purpose: Cultural and natural heritage play a crucial role in the enhancement of sustainable development strategies in rural areas, even though their full potential is still under-explored. Rural areas are currently facing common challenges related to depopulation, unemployment, poverty and ageing, making knowledge and experiences sharing a way to inspire and get insight on how to develop and implement rural regeneration strategies. The purpose of this study is to propose a knowledge framework assessment based on the analysis, documentation and mapping of successful heritage-led practices, to obtain and gather replicable lessons learnt in the form of inventory, to facilitate replicable regeneration strategies. Design/methodology/approach: The paper draws on good practices implemented by 20 Role Models and analysed in the context of the RURITAGE project, introducing the inventory of Lessons Learnt, a tool aimed at supporting and improving the use of evidence in decision-making processes and facilitating replication. Findings: The multilevel analysis described in this paper allowed to identify 40 Lessons Learnt, which were clustered according to their main area of knowledge and cross-cutting issues, demonstrating and reinforcing the importance of culture and heritage in the sustainable development of rural areas. Originality/value: This paper, through the structured analysis of information provided, contributes to support the decision-making process by improving the use of evidence and knowledge integration.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
No full textPeer reviewe
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
Full text linkPublisher 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
Full text linkPublisher 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
Full text linkPublisher 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