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LOW CO2 FOOTPRINT AND HIGH CIRCULAR CEMENTITIOUS BINDERS FOR BUILDING REHABILITATION BASED ON MINERALIZED RCF AND LF STEEL SLAGS UNDER SYNERGISTIC APPROACH
No full textPublisher Copyright: © 2024, University of Cantabria - Building Technology R&D Group. All rights reserved.The carbon dioxide (CO2) footprint reduction in conventional Portland cement production constitutes a huge challenge due to the limited availability of low carbon footprint and economic Supplementary Cementitious Materials (SCM) supplies to be employed in clinker substitution. This challenge increases when developing specific binders with a low carbon footprint for greener building rehabilitation due to the unique properties that these binders must meet, such as durability, compatibility, application flexibility and ease of use. A Carbon Capture and Utilization (CCU) approach based on mineralization by accelerated carbonation was applied to reduce sectorial carbon footprint and promote new circular building materials. In this work, a CO2 sequestration was performed on different conditions to concrete fines (RCF) and ladle furnace (LF) steel slags wastes. The amount of CO2 captured was calculated and the mineralogical transformation deeply studied and monitored by spectral tools (DRX, Raman, and Hyperspectral image HSI analysis), for process optimization. The effect of mineralization on new binders was assessed through the reactivity and accelerated pozzolanicity analysis. The obtained materials were synergistically employed as SCMin novel cementitious binders for building rehabilitation. As a result, relevant CO2 capture (between50 and 117g eq. CO2/kg by RCF and LF respectively) and lower clinker (K) content (<30%) by replacement yielded high circular low carbon footprint binders. The synergistically use of the obtained mineralized waste streams as SCM on new binders’ dosages, led to increase in pozzolanic phases generation. Carbonated RCF and LF wastes used as SCM in binders induced mechanical performance gains (achieving an increase in accelerated pozzolanic activity of 150%.) and lower environmental footprint (-27% CO2, -270kg/t of binder) than a commercial binder.This research was funded by i) IHOBE, the public environmental management company of theBasque Government (Spain), Heidelberg Materials, and VOLBAS under NEUCLICEM project; ii)the Spanish Ministry of Science and Innovation (MICINN), the Spanish National Research Agency(AEI) and the European Regional Development Fund (ERDF), ref: PID2021-122390OB-C21(CIDECAR); and iii) the Basque Government [IT1619-22 SAREN research group].Peer reviewe
Magnetic field in the extreme low frequency band protects neuronal and microglia cells from oxygen-glucose deprivation
Get PDFPublisher Copyright: Copyright © 2024 Mata, Calovi, Benli, Iglesias, Hernández, Martín, Pérez-Samartín, Ramos-Murguialday, Domercq and Ortego-Isasa.Ischemic stroke consists of rapid neural death as a consequence of brain vessel obstruction, followed by damage to the neighboring tissue known as ischemic penumbra. The cerebral tissue in the core of the lesions becomes irreversibly damaged, however, the ischemic penumbra is potentially recoverable during the initial phases after the stroke. Therefore, there is real need for emerging therapeutic strategies to reduce ischemic damage and its spread to the penumbral region. For this reason, we tested the effect of Extreme Low Frequency Electromagnetic Stimulation (ELF-EMS) on in vitro primary neuronal and microglial cultures under oxygen-glucose deprivation (OGD) conditions. ELF-EMS under basal non-OGD conditions did not induce any effect in cell survival. However, ELF-EMS significantly reduced neuronal cell death in OGD conditions and reduced ischemic induced Ca2+ overload. Likewise, ELF-EMS modulated microglia activation and OGD-induced microglia cell death. Hence, this study suggests potential benefits in the application of ELF-EMS to limit ischemic irreversible damages under in vitro stroke conditions, encouraging in vivo preclinical validations of ELF-EMS as a potential therapeutic strategy for ischemic stroke.Peer reviewe
On the black-box explainability of object detection models for safe and trustworthy industrial applications
Get PDFPublisher Copyright: © 2024 The Author(s)In the realm of human-machine interaction, artificial intelligence has become a powerful tool for accelerating data modeling tasks. Object detection methods have achieved outstanding results and are widely used in critical domains like autonomous driving and video surveillance. However, their adoption in high-risk applications, where errors may cause severe consequences, remains limited. Explainable Artificial Intelligence methods aim to address this issue, but many existing techniques are model-specific and designed for classification tasks, making them less effective for object detection and difficult for non-specialists to interpret. In this work we focus on model-agnostic explainability methods for object detection models and propose D-MFPP, an extension of the Morphological Fragmental Perturbation Pyramid (MFPP) technique based on segmentation-based masks to generate explanations. Additionally, we introduce D-Deletion, a novel metric combining faithfulness and localization, adapted specifically to meet the unique demands of object detectors. We evaluate these methods on real-world industrial and robotic datasets, examining the influence of parameters such as the number of masks, model size, and image resolution on the quality of explanations. Our experiments use single-stage object detection models applied to two safety-critical robotic environments: i) a shared human-robot workspace where safety is of paramount importance, and ii) an assembly area of battery kits, where safety is critical due to the potential for damage among high-risk components. Our findings evince that D-Deletion effectively gauges the performance of explanations when multiple elements of the same class appear in a scene, while D-MFPP provides a promising alternative to D-RISE when fewer masks are used.Peer reviewe
Development of an Innovative Carbon-Free Ecological Process as an Alternative to Explosion for Manganese Steel Hardening
No full textPublisher Copyright: © 2024 75th World Foundry Congress, WFC 2024. All rights reserved.Explosion hardening is currently the go-to method for increasing manganese steel hardness in critical applications such as railway turnouts. While effective, environmental considerations, sustainability, and competitiveness, are now more critical in industry, exposing this costly method’s weaknesses; transport to external specialists, explosions release greenhouse gases, lack precision, and disrupt the casting’s internal crystallographic network. Follow-up work is also required prior to installation. Consequently, there is a need for a more technological and cost-effective eco-hardening process, better matching today’s ethos and industrial decarbonization goals. This project presents an alternative to explosion treatment, ‘Single Process Hardening’ (SPH), which innovatively combines three established technologies for the first time in a single process: percussion hammering, ultrasonic waves, and shotblasting. Unlike the explosion method, SPH castings would not require follow-up work, e.g. crack repair, prior to installation. Following promising results using simulation software, several trial batches of 5m turnout frogs were cast, and divided between explosion hardening and SPH, prototype equipment being used for the latter. The following were analyzed; contact surface and cross-sectional hardness, permanent and residual stress, and tribological aspects. Empirical data was fed back into the software to improve future results through machine learning (AI). For analysis of all the castings, x-ray diffractometry, USM, hole ring and ring core methods were used to obtain an in-depth picture of the relevant metallurgical characteristics. With the new process, approximately one hour of treatment obtained the 400+/- HB obtained by explosion. Potentially, by tweaking the process, +/- 420HB could be obtained as the internal crystallographic integrity is not disrupted. The estimated reduction in the total cost with this new method is 75% less than using the explosion method. Regarding decarbonization goals, the elimination of road transport, and the use of green electricity, would make this method a valuable contributor.Peer reviewe
Initial Approach to Self-Compacting Concrete with Raw-Crushed Wind-Turbine Blade: Fresh, CFD and Mechanical Analysis
Get PDFPublisher Copyright: © 2024 by the authors.The production of raw-crushed wind-turbine blade (RCWTB) and its addition to conventionally designed self-compacting Concrete (SCC) enable us to provide a second life to wind-turbine blades. However, SCC containing RCWTB must show proper fresh behavior, an aspect evaluated in this paper both experimentally and through simulations based on computational fluid dynamics (CFD) for RCWTB additions up to 3.0% by volume. In experimental terms, RCWTB reduced the flowability and passing ability of SCC, and slowed SCC flow, although the performance of SCC with 1.5% RCWTB was adequate under free-flow conditions. In terms of modeling, RCWTB did not impact yield stress and increased plastic viscosity. CFD modeling under free flow, regardless of the presence or not of obstacles simulating concrete reinforcement, was successful, especially in the long term. Nevertheless, the modeling of the passing ability was not accurate; precision could be improved by simulating the effect of the individual GFRP fibers within the SCC flow. Finally, the mechanical properties of SCC were negatively impacted by RCWTB, the stitching effect of the GFRP fibers not being effective in an SCC with a conventional design. A specific SCC design when adding RCWTB is therefore needed to advance in the use of this waste in this concrete type.Peer reviewe
Repair of Beam End Joints Using Steel Rods and Wood Prosthesis in Heritage Buildings: Implantation in the Structure of the Zabala Palace in Ordizia (Basque Country, Spain)
Get PDFPublisher Copyright: © 2024 by the authors.This paper presents the methodology developed in the repair of three oak beam ends in a protected heritage building: the Zabala Palace in Ordizia (Basque Country, Spain). It describes the structural assessment, design, calculation and execution process, as well as the experimental tests carried out in the laboratory to verify and validate the structural capacity of the repair method. The intervention consisted of cutting and removing the beam ends degraded by fungi and replacing them with wooden prostheses. These elements were connected to the beams by means of threaded steel rods and epoxy resin. Calculations based on standards and the literature were verified by laboratory tests where aspects such as the fluidity, filling and pull-out resistance of four commercial epoxy resins were tested. Once the epoxy resin was selected, three samples of the reinforcement design were also flexure tested. The results of the different tests show capacities much higher than those resulting from the application of the calculation procedures in the current bibliography and standards. The implemented solution allowed the conservation of most of the original patrimonial timber, following the criteria of minimum intervention.Peer reviewe
HAPPENING: an efficient cascade heat pump system for multifamily buildings
Get PDFAn innovative hybrid heat pump system is presented as a novel solution for multifamily building heating system retrofitting. This system is very efficient on the one hand thanks to its innovative configuration in cascade, minimum thermal losses and on the other hand, the maximization of local solar energy self-consumption due to decoupling generation and consumption and applying smart control strategies. It is aimed at facilitating retrofitting of existing heating systems in multifamily buildings, enabling an efficient decarbonization. Three variations of the system have been designed, installed, and tested in real buildings across Europe, within the H2020 project “HAPPENING”. The project is now under monitoring phase and the preliminary results are positive, demonstrating the high efficiency of the concept.This system has been developed within the European project “HAPPENING” with funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 957007.This system has been developed within the European project “HAPPENING” with funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 957007.Non peer reviewe
Enhancing Additive Manufacturing: A Continuum Material Topology Optimization Approach
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Optimización del rendimiento de vehículos eléctricos híbridos: una visión detallada de las estrategias de gestión de energía.
Get PDFPublisher Copyright: © 2024 by the authors.Rising greenhouse gas emissions stemming from road transport have intensified the need for efficient and environmentally friendly propulsion technologies. Hybrid and fuel cell electric vehicles have emerged as a viable solution, integrating internal combustion engines and fuel cells with electric motors to optimize fuel efficiency and reduce emissions. This article reviews and analyzes energy management strategies for the principal powertrain topologies of hybrid electric vehicles, focusing on achieving solution optimality in real-time applications. A thorough and comprehensive overview of rule-based, optimization-based, and learning-based energy management strategies is presented, highlighting their main attributes and providing a comparative analysis in terms of fuel economy improvements, real-time implementation feasibility, and computational complexity, while simultaneously identifying and uncovering areas requiring further research in the field. We found that while rule-based methods offer simplicity and real-time capability, their adaptability remains limited. Optimization-based and learning-based approaches, although often achieving near-optimal solutions, face challenges due to their high computational demands and integration complexities. Our analysis also revealed the importance of leveraging vehicle connectivity and intelligent transportation systems for future energy management developments, which will contribute to broader sustainability goals in the automotive sector.Peer reviewe
Towards Interoperability Testing of Smart Energy Systems - An Overview and Discussion of Possibilities
No full textPublisher Copyright: © The Institution of Engineering & Technology 2024.Interoperability is the key to implementing a wide range of energy systems applications. It involves the seamless cooperation of different methods and components. With smart energy systems, interoperability faces challenges due to integrating different approaches and technologies. This includes dealing with heterogeneous approaches with various communication protocols and data formats. However, it is essential for smart energy systems to carry out thorough interoperability tests. They are usually diverse, and challenging, thus requiring careful consideration of compatibility issues and complex integration scenarios. Overcoming these challenges requires a systematic approach that includes thorough test planning, rigorous testing, and continuous test monitoring. Although numerous testing approaches exist, most are more developed at the component/device level than at the system level. Consequently, there are few approaches and related facilities to test the interoperability of smart energy approaches and solutions at the system level. This work analyses existing interoperability test concepts, identifies enablers and the potential for harmonisation of procedures, and proposes further developments of these approaches.Peer reviewe