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Single-Mode-Multimode-Single-Mode Fiber (SMS): Exploring Environmental Sensing Capabilities
No full textPublisher Copyright: © 2017 IEEE.In this letter, we study the environmental sensing capabilities of a single-mode-multimode-single-mode (SMS) fiber in a simple low-cost configuration. SMS fibers exhibit sensitivity to temperature, humidity, refractive index, and strain, making them suitable for numerous applications in telecommunications, environmental monitoring, and more. Experimental results demonstrate that the sensor achieves a maximum temperature sensitivity of 4.53 nm/°C. In addition, SMS fibers can also work as humidity sensors by absorbing or releasing moisture, leading to variations in the refractive index. Monitoring these changes allows for precise humidity measurements, with a sensitivity of 0.1548 nm/%RH. Moreover, SMS fibers show a refractive index sensitivity of 39.65 nm/RIU and strain sensitivities as high as 1.062 nm/μϵ, indicating good performance.Peer reviewe
Mini-C(T) specimens for Master Curve analysis of structural steels operating within their ductile-to-brittle transition region
No full textPublisher Copyright: © 2024 The Author(s)This work uses mini-C(T) specimens, validated on nuclear steel grades, to characterize the fracture behavior of structural steels. Mini-C(T) specimens are significantly smaller (4 mm thick) than conventional fracture specimens and allow testing a large number of specimens with limited material. The research involves four common structural steels (S275JR, S355J2, S460M and S690Q), and involves testing, ASTM E1921 application and fractographical analyses. Findings demonstrate that mini-C(T) specimens effectively capture the fracture behavior of structural steels, providing reasonable T0 values. Results show a difference of about ±30 °C comparing mini-C(T) and conventional specimens, suggesting the potential of mini-C(T) specimens for T0 characterization.Peer reviewe
A roadmap towards safe and sustainable by design nanotechnology: Implementation for nano-silver-based antimicrobial textile coatings production by ASINA project
Get PDFPublisher Copyright: © 2024 The AuthorsThis report demonstrates a case study within the ASINA project, aimed at instantiating a roadmap with quantitative metrics for Safe(r) and (more) Sustainable by Design (SSbD) options. We begin with a description of ASINA's methodology across the product lifecycle, outlining the quantitative elements within: Physical-Chemical Features (PCFs), Key Decision Factors (KDFs), and Key Performance Indicators (KPIs). Subsequently, we delve in a proposed decision support tool for implementing the SSbD objectives across various dimensions—functionality, cost, environment, and human health safety—within a broader European context. We then provide an overview of the technical processes involved, including design rationales, experimental procedures, and tools/models developed within ASINA in delivering nano-silver-based antimicrobial textile coatings. The result is pragmatic, actionable metrics intended to be estimated and assessed in future SSbD applications and to be adopted in a common SSbD roadmap aligned with the EU's Green Deal objectives. The methodological approach is transparently and thoroughly described to inform similar projects through the integration of KPIs into SSbD and foster data-driven decision-making. Specific results and project data are beyond this work's scope, which is to demonstrate the ASINA roadmap and thus foster SSbD-oriented innovation in nanotechnology.Peer reviewe
Streamlining Renovation Workflow through Process Digitalization: Enhancing Information Flow, Accelerating Decision-Making, and Reducing Costs in the early stages of the renovation process
No full textPublisher Copyright: © Copyright by Fundacja PLEA 2024 Conference, Wrocław 2024.In typical practice of building renovation design, distributed teams communicate through technical drawings, but the construction industry lags in digitalization. This study addresses this gap by proposing a methodological framework integrated into digital tools for early-stage renovation processes. The framework, implemented as a web-based tool, gathers user inputs related to building details and preferences to generate alternative renovation scenarios. It utilizes databases for building characteristics, technologies, and life cycle assessment (LCA)/life cycle cost (LCC) calculations. The information flow involves user inputs, database storage, and processing layers, enabling simulations and scenario evaluations. The framework facilitates quick, cost-effective, and customized decision-making in the early design phases, aiming for energy-efficient retrofits. Results highlight the importance of databases, such as building characteristics and LCA/LCC, while emphasizing a clear communication protocol among stakeholders. Overall, the study seeks to accelerate and streamline the renovation process, promoting efficient collaboration and reducing time and costs.Peer reviewe
Generation of lossy mode resonances (LMR) using perovskite nanofilms
No full textPublisher Copyright: © The Author(s) 2024. Published by Institute of Optics and Electronics, Chinese Academy of Sciences.The results presented here show for the first time the experimental demonstration of the fabrication of lossy mode resonance (LMR) devices based on perovskite coatings deposited on planar waveguides. Perovskite thin films have been ob-tained by means of the spin coating technique and their presence was confirmed by ellipsometry, scanning electron mi-croscopy, and X-ray diffraction testing. The LMRs can be generated in a wide wavelength range and the experimental results agree with the theoretical simulations. Overall, this study highlights the potential of perovskite thin films for the development of novel LMR-based devices that can be used for environmental monitoring, industrial sensing, and gas de-tection, among other applications.Peer reviewe
Comprehensive Experimental Database and Model Fitting for Electric Arc Behavior in Aircraft Environments
No full textPublisher Copyright: © 2024, European Association for the Development of Renewable Energy, Environment and Power Quality (EA4EPQ). All rights reserved.The More Electric Aircraft (MEA) paradigm advocates weight reduction by transitioning to electrical components, resulting in increased system voltage and higher arc fault risk. This paper presents a methodology for creating a database of nearly one thousand tests simulating parallel arc faults, using Andrea's arc model for accurate representation. Objectives include the creation of a robust experimental database and the use of a simplified model to analyze arcing behavior. The setup follows the UL 746A standard and considers various pressure and electrode separation conditions. The database includes 960 experiments with PVC and PTFE materials, and model fitting ensures accurate representation of arc currents and voltages. Error analysis shows consistent model performance across materials and highlights sensitivity to electrode spacing, pressure, and source voltage. The paper concludes with a clear 30% error threshold for model validity, enhancing the understanding of the applicability of Andrea's model under various experimental scenarios in aircraft environments.Peer reviewe
“On-The-Fly” Synthesis of Self-Supported LDH Hollow Structures Through Controlled Microfluidic Reaction-Diffusion Conditions
No full textPublisher Copyright: © 2023 The Authors. Small published by Wiley-VCH GmbH.Layered double hydroxides (LDHs) are a class of functional materials that exhibit exceptional properties for diverse applications in areas such as heterogeneous catalysis, energy storage and conversion, and bio-medical applications, among others. Efforts have been devoted to produce millimeter-scale LDH structures for direct integration into functional devices. However, the controlled synthesis of self-supported continuous LDH materials with hierarchical structuring up to the millimeter scale through a straightforward one-pot reaction method remains unaddressed. Herein, it is shown that millimeter-scale self-supported LDH structures can be produced by means of a continuous flow microfluidic device in a rapid and reproducible one-pot process. Additionally, the microfluidic approach not only allows for an “on-the-fly” formation of unprecedented LDH composite structures, but also for the seamless integration of millimeter-scale LDH structures into functional devices. This method holds the potential to unlock the integrability of these materials, maintaining their performance and functionality, while diverging from conventional techniques like pelletization and densification that often compromise these aspects. This strategy will enable exciting advancements in LDH performance and functionality.Peer reviewe
Migration of an industrial application to a Quantum Safe environment: Industrial QKD communications.
Get PDFThis article presents the knowledge transfer carried out between TECNALIA and I3B regarding Quantum Key Distribution (QKD) technology for its deployment in a real industrial application. QKD has been studied for some time, but only recently have commercial devices become available that can meet the requirements of industrial systems. The article addresses the integration of quantum cryptography into a common industrial process, namely the loading of programs onto factory PLCs from the engineering plant. On one hand, a theoretical scenario is proposed, along with a method for integration and a network-level deployment proposal. On the other hand, the article describes the deployment of a QKD link over existing infrastructure, where a series of experiments are conducted to evaluate the maturity of the solution for the presented use case.Non peer reviewe
Decentralized Most Permissive Observer Architecture for Brake Leakage Diagnosis in Automotive Systems
No full textPublisher Copyright: © 2024 The Authors.Brake systems represent one of the most critical components contributing to the safety of modern automotive systems. They are commonly referenced as one of the most vehicle-related factors in fatal crashes. Usually, the faults in this type of component are provoked by brake fluid leaks affecting the performance and response of the entire system, which require manual maintenance procedures to locate the source of the problem. This study presents a novel Discrete Event System (DES) model capable of detecting brake fluid leakage faults using a decentralized Most Permissive Observer (MPO) architecture for fault diagnosis. The developments were verified via an enhanced virtual environment employing a simulation model of the braking system using Simscape and assessing the event-driven fault diagnosis scheme using Stateflow. A ‘Design of Experiment’ method is performed using a factorial design of 3k, where k is the number of levels of a factor in the factorial experiment (in this paper k is 4), to conduct the assessment of test cases that combined edge values. The efficacy of the proposed DES model for fault diagnosis is demonstrated across a wide range of simulated scenarios, including fault locations, pressure drops, and single and multiple fault combinations. The proposed method consistently diagnoses the injected fault conditions, showcasing its efficiency under diverse operational conditions of the braking system.Peer reviewe
Origins and trajectory of the nuclear fuel industry in SpainENUSA, 1972-2022
No full textPublisher Copyright: © 2023 The Author(s)This article aims to examine the deployment of the industrial fabrication of nuclear fuel in Spain, a highly specialized activity linked to the Empresa Nacional del Uranio SA (National Uranium Company, ENUSA) and the supply of foreign technology (Westinghouse and General Electric). ENUSA was founded, at the initiative of the government and with the support of the private sector, to cover the fuel needs of a tremendously ambitious nuclear program, which was later reduced to a quarter of what had been foreseen. After some years of uncertainty, the state-owned company managed to successfully overcome the difficulties arising from the industrial reconversion and the change in the government’s energy policy, reaching the 21st century as a company which is not merely a survivor but a leader in its sector of activity: its plant at Juzbado (Salamanca) has become a technological and industrial reference, with wide geographical and sectorial spillovers. In short, we will try to reconstruct the origins of ENUSA and to search in the past for the reasons for its current position, based on a wide range of mostly archival sources.Peer reviewe