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Spanish labour market, mobility and labour shortages
No full textWe use a simple yet powerful approach to investigate the dynamics of worker flows across sectors in the Spanish economy. The method imposes a minimal amount of structure on the data by assuming sector-specific matching functions, and backs out the direction of workers’ search intensities across sectors using data on realised worker flows and vacancies.We find that aggregate search intensity in Spain has been increasing since the pandemic and has led aggregate labour shortages to be below pre-pandemic levels by 2023. However, this boost of search intensity is directed to industries with low matching efficiencies and job finding rates. As a result, aggregate match formation is near to a 10-years low relative to the number of matches that would result if search intensity was allocated to maximise total matches given the observed vacancy distribution and match efficiencies across sectors.Funding from Fundación BBVA, an impact grant from the University of Edinburgh, and by grants CEX2021- 001181-M andATR2023-145734 funded by MICIU/AEI /10.13039/501100011033 (Unidades de Excelencia Maria de Maeztu, and Programa ATRAE, Spanish Government) is gratefully
acknowledged
Effect of Plasma Treatment on Coating Adhesion and Tensile Strength in Uncoated and Coated Rubber Under Aging
Get PDFThe degradation of rubber materials under environmental and mechanical stress presents a significant challenge, particularly due to UV (ultraviolet light) exposure, which severely impacts the material’s physical properties. This study aims to enhance the UV stability and longevity of rubber by evaluating the performance of modified polyurethane and silicone coatings as protective stabilizers. Natural rubber—styrene–butadiene rubber (NR-SBR), known for its exceptional mechanical properties, was selected as the base material. To ensure strong adhesion, cold atmospheric plasma treatment was applied, increasing the surface energy by 250%, primarily through an enhancement of the polar component. After treatment, supplier-recommended coatings were applied and tested for adhesion using the pull-out method. Aging tests under UV exposure, water immersion, and high temperatures were conducted to assess durability, with tensile tests used to monitor changes over time. Coatings exhibiting cracking after UV exposure were excluded from further analysis. A silicone coating demonstrating superior moisture resistance and durability under extreme conditions was identified as a promising candidate for future UV stabilization applications. These findings provide a foundation for developing advanced coatings to significantly extend the service life of rubber materials in demanding environments
Testing mirror symmetry in the Universe with LIGO-Virgo black-hole mergers
No full textCertain precessing black-hole mergers produce gravitational waves with net circular polarization, understood as an imbalance between right- and left-handed amplitudes. According to the cosmological principle, such emission must average to zero across all binary mergers in our Universe to preserve mirror-reflection symmetry at very large scales. We present a new independent gravitational-wave test of this hypothesis. Using a novel observable based on the Chern-Pontryagin pseudoscalar, we measure the emission of net circular polarization across 47 black-hole mergers recently analyzed by [T. Islam et al., arXiv:2309.14473.] with a state-of-the art model for precessing black-hole mergers in general relativity. The average value obtained is consistent with zero. Remarkably, however, we find that at least 82% of the analyzed sources must have produced net circular polarization. Of these, GW200129 shows strong evidence for mirror asymmetry, with a Bayes factor of 12.6 or, equivalently, 93.1% probability. We obtain consistent (although stronger) results of 97.5% and 94.3%, respectively, using public results on this event from [M. Hannam et al., Nature (London) 610, 652 (2022).] and performing our own parameter inference. This finding further implies evidence of astrophysical sources that can spontaneously emit circularly polarized photons by quantum effects. Forthcoming black-hole merger detections will enable stronger constraints on large-scale mirror asymmetry and the cosmological principle.JCB is funded by a fellowship from “la Caixa” Foundation (ID100010474) and from the European Union’s Horizon2020 research and innovation programme under the Marie Skodowska-Curie grant agreement No 847648. The fellowship code is LCF/BQ/PI20/11760016. JCB is also supported by the research grant PID2020-118635GB-I00 from the Spain-Ministerio de Ciencia e Innovación and by its Ram´on y Cajal program (grant RYC2022-036203-I). ADR acknowledges support through (i) Maria Zambrano grant ZA21-048 with reference UP2021-044 from the Spanish Ministerio de Universidades, funded within the European Union-Next Generation EU, and (ii) Atraccion de Talento Cesar Nombela grant No 2023-T1/TEC-29023, funded by Comunidad de Madrid (Spain). ADR further acknowledges financial support via the Spanish Grants PID2020-116567GBC21, funded by MCIN/AEI/10.13039/501100011033, and PID2023-149560NB-C21, funded by MCIU /AEI/10.13039/501100011033/FEDER, UE. NSG acknowledges support from the Spanish Ministerio de Universidades, through a Mar´ıa Zambrano grant (ZA21-031) with reference UP2021-044, funded within the European Union-Next Generation EU, and from the Spanish Ministry of Science and Innovation via the Ramón y Cajal programme (grant RYC2022-037424-I), funded by MCIN/AEI/ 10.13039/501100011033 and by “ESF Investing in your future”. NSG is further supported by the Spanish Agencia Estatal de Investigaci ´on (Grant PID2021-125485NB-C21) funded by MCIN/AEI/10.13039/501100011033 and ERDF A way of making Europe, and by the European Union’s Horizon 2020 research and innovation (RISE) programme H2020-MSCA-RISE-2017 Grant No. FunFiCO-777740 and by the European Horizon Europe staff exchange (SE) programme HORIZON-MSCA2021-SE-01 Grant No. NewFunFiCO-101086251. KC acknowledges the support through NSF grant numbers PHY-2207638, AST-2307147, PHY-2308886, and PHY-2309064. We acknowledge the use of IUCAA LDG cluster Sarathi for the computational/numerical work. The authors acknowledge computational resources provided by the CIT cluster of the LIGO Laboratory and supported by National Science Foundation Grants PHY-0757058 and PHY0823459; and the support of the NSF CIT cluster for the provision of computational resources for our parameter inference runs
Is a single model enough? The systematic comparison of computational approaches for detecting populist radical right content
Get PDFGermanophone test datasets and how their performance is affected by different modes of text preprocessing. In addition to individual models, we examine the performance of 330 ensemble models combining the above-mentioned approaches for the dataset with a particularly high volume of noise. Our findings demonstrate that the DL models, in combination with more computationally intense forms of preprocessing, show the best performance among the individual models, but it remains suboptimal in the case of more noisy datasets. While the use of ensemble models shows some improvement for specific modes of preprocessing, overall, it mostly remains on par with individual DL models, thus stressing the challenging nature of computational detection of PRR content
Wireless Charger for Pacemakers Controlled from Primary Current Without Communication with Secondary Side
No full textThis paper discusses the implementation of a wireless inductive power transfer system for pacemaker applications. One of the inherent challenges in these systems is regulating the output voltage, as there is no direct physical connection from the primary. Additionally, there are other challenges, such as variability in magnetic coupling. First, resonant converters for inductive charging topologies are investigated for biomedical applications. Then, a control method based on the system's modeling is proposed, eliminating the need for communication. This method is designed for systems with variable and unknown coupling and specifically for a resonant series¿parallel topology. For an operation point, determined by the coupling factor, the primary current is measured to regulate the output voltage by adjusting the input voltage. The relationship between the input current and the input voltage is set by a look-up table. The effectiveness of this control strategy is validated in the PSIM simulator and with experimental results for a coupling range between 0.3 and 0.5, achieving a regulated output current error of less than 1%, and an output voltage range within the limits of the battery charger.This work has been partially supported by the Spanish Ministry of Science, Innovation, and Universities through the research project HIDRON (PID2020-116500RB-I00/AEI/10.13039/501100011033); by the Regional Council of Science, Universities, and Innovation of the Community of Madrid through the research project DROMADER-CM (Y2020/NMT-6584/SINERGICOS), and Grant TED2021-129240B-I00 funded by MICIU/AEI/10.13039/501100011033 and, as appropriate, by the “European Union NextGenerationEU/PRTR”
Green growth in the mirror of history
No full text'Green growth' is a cornerstone of global sustainability debates and policy agenda. Although there is no consensus definition, it is commonly associated with the absolute decoupling of economic growth from greenhouse gas emissions, which is indeed occurring in high-income countries today. Nevertheless, green growth thus defined could be insufficient to reach global mitigation goals. Here we examine long-term historical data and develop a framework to identify global, regional, and national patterns of decoupling between economic output and anthropogenic greenhouse gas emissions. We show that 60% of cumulative fossil-fuel CO2 reduction during 1820-2022 took place under recessions rather than during instances of green growth, with just 5 global crises accounting for about 40%. While in the last 50 years national episodes of green growth became more common, they have not been sustained over time. Crucially, historical episodes compatible with sustained growth and the required emission reductions are anecdotal.This project has been partially financed by the State Research Agency (SRA) and the European Regional Development Fund (ERDF) (grant numbers AEI/PID2021-124394NB-I00, with E.T. as a member of the research team, and AEI/PID2021-123220NB-I00, awarded to J.I.A.), Areces Foundation (grant number CISP19A6420, awarded to J.I.A.) and the European Research Council (ERC) under the European Union’s Horizon Europe research and innovation program (ERC StG Project 101115126 “WHEP,” awarded to E.A.). E.A. is supported by a Ramón y Cajal Grant (RYC2022-037863-I), funded by MICIU/AEI /10.13039/501100011033 and by the European Social Fund Plus (ESF+)
Si nanowires versus Si bulk systems: a comparative study of their optical properties
No full textWe theoretically investigate the effects of the embedding media and the geometrical sizes on the optical properties of a periodic square array of Si nanowires (NWs). We compare the above properties with those of Si bulk film. This simulated system is made of four stacked layers along a semi-infinite air space. The stacked layer system is defined by a transparent layer of ITO, the active layer of Si NWs embedded into the filling medium, the polymer layer PMMA and the substrate of SiO2. The Si bulk film system is also characterized by the same layers, but the active layer is constituted by the Si bulk instead of Si NWs. The multilayer absorbance is simulated by the Transfer Matrix Method, while the Si NW system is treated as an homogeneous layer whose effective dielectric function is described by the Bruggeman model. For both s- and p-polarizations at normal and oblique incidences, we report a typical oscillating behavior in the absorbance/reflectance spectra, regardless of the type of system (Si film or Si NWs), the type of embedding medium and sizes in Si NWs. Greater diameter-to-periodicity ratio (D/P) for longer Si NWs benefit the light absorption up to 80 per cent in the VIS range. Indeed, the absorbance values of the Si NW system are higher than those of the Si bulk film when the amount of silicon material is identical in both systems.This work is supported by Comunidad de Madrid under Project TECHNOFUSION III CM-S2018IEMAT-4437. This work has also been supported by Comunidad de Madrid under the agreement with UC3M, within the Excellence of University Professors (EPUC3M14)
A family of experiments to quantify the benefits of adopting WebDriverManager and Selenium-Jupiter
Get PDFContext: While test automation offers numerous benefits, it also introduces significant challenges. Two challenges that developers and testers face on a daily basis, particularly when using Selenium WebDriver to test web applications, are driver management (involving tasks such as version identification, download, installation, and maintenance) and management of test lifecycle phases (using specific test libraries, as for example JUnit, and inserting annotations into the code). These manual tasks make test suite development particularly tedious, error-prone, and expensive. Recently, to ease the burden on developers and testers, some Java libraries have been proposed, called WebDriverManager and Selenium-Jupiter, capable of automatically carrying out the driver management process for Selenium WebDriver and simplifying the development of test suites. These libraries appear to be very promising but until now no one has experimentally evaluated their effectiveness.
Objective: To investigate the effectiveness of WebDriverManager and Selenium-Jupiter in reducing driver management times and boilerplate code.
Method: We designed and conducted a family of experiments (three for WebDriverManager and two for Selenium-Jupiter) with 104 master student participants from the University of Genoa, Italy (across academic years 2021/2022 and 2022/2023) and nine professional participants.
Results: Results indicate that the adoption of Selenium WebDriver with WebDriverManager significantly reduces setup time for multi-browser test suites from 33% to 50% (depending on the tester experience). Additionally, Selenium-Jupiter reduces test suite development time significantly (20% on average). Although it also decreases total code length, the reduction is relatively small compared to overall code length.
Conclusion: WebDriverManager and Selenium-Jupiter can be seen as valuable solutions for enhancing testers' productivity by shortening the time needed to develop test suites and minimizing the amount of code to write.This study was partially carried out within the “EndGame - Improving End-to-End Testing of Web and Mobile Apps through Gamification” project (2022PCCMLF) – funded by European Union – Next Generation EU within the PRIN 2022 program (D.D.104 - 02/02/2022 Ministero dell’Università e della Ricerca). This work has also been partially supported by the “Generation of Reliable Synthetic Health Data for Federated Learning in Secure Data Spaces” Research Project (PID2022-141045OB-C43 (AEI/ERDF, EU)) funded by MCIN/AEI/ 10.13039/501100011033 and by “ERDF A way of making Europe” by “the European Union”, and by the MCIN/AEI/ 10.13039/501100011033 through the H2O Learn Research Project (PID2020-112584RB-C31)
Uplink Non-Orthogonal Multiple Access (NOMA) Decoding based on Successive Parzen Windows Interference Cancellation
Get PDFIn this paper, a novel decoding kernel method based on Successive Parzen Windows Interference Cancellation (SPWIC) is proposed for the Non-Orthogonal Multiple Access (NOMA) uplink. The procedure leverages on the diversity in both angle and received power at a 3D antenna combined with a Parzen Windows based decoding to achieve better interference cancellation, providing the decoding process with robustness against multi-user interference and user discrimination. This is specially convenient in vehicular scenarios in crowded cities. We have evaluated SPWIC in various scenarios and concluded that it outperforms the standard Successive Interference Cancellation (SIC) approach even in Multiple-Input Multiple-Output (MIMO) cases such that up to 9 users can be allocated on the same resources -as long as they are not too close to each other-. Although it is proposed for mmWave, it can be directly adapted to lower frequencies.This work was supported in part by project PID2023-147305OB-C31 (SOFIA-AIR) by MICIU/AEI/10.13039/501100011033/ERDF and in part by project PASSIONATE under CHIST-ERA grant CHIST-ERA-22-WAI-04 by AEI PCI2023-145990-2