84 research outputs found

    Preservice teachers’ perceptions of linguistic abilities and privacy policies in the use of visual materials during their own and their tutors’ lessons

    Get PDF
    This article analyzes the capacity for improvement of digital observation in initial teacher training to investigate whether the implementation of visual materials is effective for the reinforcement of previously taught content, the assessment of one’s own linguistic abilities and whether it motivates learners. To do so, the subjects analyzed classroom behavior and learning typology through the reflection of their own videos recorded with children and tutors. Data was collected through 12 closed-ended questions that follow the Likert scale and one open-ended question for general reflection. The questions focused on the motivation and interest of the students with respect to the videos viewed, comprehension, learning, perceived usefulness, and the problem arising with the privacy of the Students’ personal data. The responses were classified and their frequencies and percentages were calculated. The results show that implementing video tools in the classroom and reflecting on their content afterward can be an effective means of assessing one’s learning and language skills. In addition, the study highlights the inherent complexities posed by EU GDPR regulations and the significant barriers to integrating video technology into the classroom for schoolchildren in these contexts.Xunta de Galicia | Ref. ED431C-2021/5

    Numerical analysis of high velocity impacts on unidirectional laminates

    Get PDF
    In this work a numerical methodology to predict the behavior of composite unidirectional laminates under high velocity impact is developed. In order to validate the model, experimental results of high velocity impacts of steel sphere against laminate coupons, were accomplished. The residual velocity in case of penetration and the damaged area in the panel are the variables chosen to validate the results obtained in the numerical methodology proposed. Finally an analysis of the influence of the projectile geometry is accomplished. (C) 2013 Elsevier Ltd. All rights reserved

    Pulsed 193 nm Excimer laser processing of 4H–SiC (0001) wafers with radiant exposure dependent in situ reflectivity studies for process optimization

    Get PDF
    Apoyo científico y técnico del CACTI193 nm Excimer lasers are efficient tools to process group-IV semiconductors for advanced microelectronic and photonic devices through crystallization annealing, or strain engineering. The combination of both, high photon energy and low penetration depth of the 193 nm laser pulses allow breaking most covalent bonds with a single photon, and low thermal budget treatments through a precise control of the laser processed volume. Up to now, studies using 193 nm lasers for silicon carbide (SiC) processing are mostly limited to ablation processes for micromachining purposes. This paper presents a first study to demonstrate that the optimization of other processes, like the creation or annealing of vacancies, the alloying of SiC surfaces or the selective ablation of silicon or carbon should also be feasible. To develop such laser assisted processes and optimize process parameters, a numerical simulation of the laser/material interaction is essential. This implies that the temporal evolution of the laser pulse must be well known, and that an “in-situ measurement” of the response of the material to the laser pulse should be available. This study therefore evaluates the temporal profile of a new high-power Excimer laser, and presents the results of in-situ Time Resolved Reflectivity (TRR) measurements obtained when irradiating 4H–SiC(0001) wafers with radiant exposures ranging from 0,1 J/cm2 to 3,0 J/cm2. The temporal pulse profile is determined, fitted and applied in a 1-D numerical simulation of the temperature gradients for Si(100) as reference sample, to validate the experimental findings. Radiant exposure thresholds at around 1,4 J/cm2 to locally produce molten surfaces and 1,8 J/cm2 to ablate and create carbon-rich regions with graphene, are determined in-situ and confirmed by Raman spectroscopy.Los láseres Excimer de 193 nm son herramientas eficaces para procesar semiconductores del grupo IV para dispositivos microelectrónicos y fotónicos avanzados mediante recocido de cristalización o ingeniería de deformación. La combinación de la alta energía fotónica y la baja profundidad de penetración de los pulsos láser de 193 nm permite romper la mayoría de los enlaces covalentes con un solo fotón, y tratamientos de bajo presupuesto térmico mediante un control preciso del volumen procesado por láser. Hasta ahora, los estudios que utilizan láseres de 193 nm para el procesado de carburo de silicio (SiC) se limitan principalmente a procesos de ablación con fines de micromecanizado. Este trabajo presenta un primer estudio para demostrar que la optimización de otros procesos, como la creación o recocido de vacantes, la aleación de superficies de SiC o la ablación selectiva de silicio o carbono también debería ser factible. Para desarrollar estos procesos asistidos por láser y optimizar los parámetros del proceso, es esencial realizar una simulación numérica de la interacción entre el láser y el material. Esto implica que debe conocerse bien la evolución temporal del pulso láser y que debe disponerse de una "medición in situ" de la respuesta del material al pulso láser. Por lo tanto, este estudio evalúa el perfil temporal de un nuevo láser Excimer de alta potencia, y presenta los resultados de las medidas in-situ de Reflectividad Resuelta en el Tiempo (TRR) obtenidas al irradiar obleas de 4H-SiC(0001) con exposiciones radiantes que oscilan entre 0,1 J/cm2 y 3,0 J/cm2. El perfil temporal del pulso se determina, ajusta y aplica en una simulación numérica 1-D de los gradientes de temperatura para Si(100) como muestra de referencia, para validar los resultados experimentales. Los umbrales de exposición radiante en torno a 1,4 J/cm2 para producir localmente superficies fundidas y 1,8 J/cm2 para ablacionar y crear regiones ricas en carbono con grafeno, se determinan in situ y se confirman mediante espectroscopia Raman.Xunta de Galicia | Ref. ED431C-2021/49Agencia Estatal de Investigación | Ref. TED2021-131760B-I00Universidade de Vigo/CISU

    rDock: A Fast, Versatile and Open Source Program for Docking Ligands to Proteins and Nucleic Acids

    Full text link
    Identification of chemical compounds with specific biological activities is an important step in both chemical biology and drug discovery. When the structure of the intended target is available, one approach is to use molecular docking programs to assess the chemical complementarity of small molecules with the target; such calculations provide a qualitative measure of affinity that can be used in virtual screening (VS) to rank order a list of compounds according to their potential to be active. rDock is a molecular docking program developed at Vernalis for high-throughput VS (HTVS) applications. Evolved from RiboDock, the program can be used against proteins and nucleic acids, is designed to be computationally very efficient and allows the user to incorporate additional constraints and information as a bias to guide docking. This article provides an overview of the program structure and features and compares rDock to two reference programs, AutoDock Vina (open source) and Schrodinger's Glide (commercial). In terms of computational speed for VS, rDock is faster than Vina and comparable to Glide. For binding mode prediction, rDock and Vina are superior to Glide. The VS performance of rDock is significantly better than Vina, but inferior to Glide for most systems unless pharmacophore constraints are used; in that case rDock and Glide are of equal performance. The program is released under the Lesser General Public License and is freely available for download, together with the manuals, example files and the complete test sets, at http://rdock.sourceforge.net

    Studying the Effect and Treatment of Misspelled Queries in Cross-Language Information Retrieval

    Get PDF
    [Abstract] The performance of Information Retrieval systems is limited by the linguistic variation present in natural language texts. Word-level Natural Language Processing techniques have been shown to be useful in reducing this variation. In this article, we summarize our work on the extension of these techniques for dealing with phrase-level variation in European languages, taking Spanish as a case in point. We propose the use of syntactic dependencies as complex index terms in an attempt to solve the problems deriving from both syntactic and morpho-syntactic variation and, in this way, to obtain more precise index terms. Such dependencies are obtained through a shallow parser based on cascades of finite-state transducers in order to reduce as far as possible the overhead due to this parsing process. The use of different sources of syntactic information, queries or documents, has been also studied, as has the restriction of the dependencies applied to those obtained from noun phrases. Our approaches have been tested using the CLEF corpus, obtaining consistent improvements with regard to classical word-level non-linguistic techniques. Results show, on the one hand, that syntactic information extracted from documents is more useful than that from queries. On the other hand, it has been demonstrated that by restricting dependencies to those corresponding to noun phrases, important reductions of storage and management costs can be achieved, albeit at the expense of a slight reduction in performance.Ministerio de Economía y Competitividad; FFI2014-51978-C2-1-RRede Galega de Procesamento da Linguaxe e Recuperación de Información; CN2014/034Ministerio de Economía y Competitividad; BES-2015-073768Ministerio de Economía y Competitividad; FFI2014-51978-C2-2-

    Reconciliation of the carbon budget in the ocean’s twilight zone

    Get PDF
    Photosynthesis in the surface ocean produces approximately 100 gigatonnes of organic carbon per year, of which 5 to 15 per cent is exported to the deep ocean1, 2. The rate at which the sinking carbon is converted into carbon dioxide by heterotrophic organisms at depth is important in controlling oceanic carbon storage3. It remains uncertain, however, to what extent surface ocean carbon supply meets the demand of water-column biota; the discrepancy between known carbon sources and sinks is as much as two orders of magnitude4, 5, 6, 7, 8. Here we present field measurements, respiration rate estimates and a steady-state model that allow us to balance carbon sources and sinks to within observational uncertainties at the Porcupine Abyssal Plain site in the eastern North Atlantic Ocean. We find that prokaryotes are responsible for 70 to 92 per cent of the estimated remineralization in the twilight zone (depths of 50 to 1,000 metres) despite the fact that much of the organic carbon is exported in the form of large, fast-sinking particles accessible to larger zooplankton. We suggest that this occurs because zooplankton fragment and ingest half of the fast-sinking particles, of which more than 30 per cent may be released as suspended and slowly sinking matter, stimulating the deep-ocean microbial loop. The synergy between microbes and zooplankton in the twilight zone is important to our understanding of the processes controlling the oceanic carbon sink

    (árabe - العربية‎) 2022 الرزنامة الدراسية العلمية

    Get PDF
    El proyecto “Calendario Científico Escolar 2022” ha consistido en la elaboración de un calendario dirigido al alumnado de educación primaria y secundaria obligatoria. Cada día se ha recogido un aniversario científico o tecnológico como, por ejemplo, nacimientos de personas de estos ámbitos o conmemoraciones de hallazgos destacables. Además, el calendario se acompaña de una guía didáctica con orientaciones para el aprovechamiento educativo transversal del calendario en las clases, incluyendo actividades adaptadas a cada rango de edad y al alumnado con necesidades especiales.Proyecto FCT-20-16375 de la Fundación Española para la Ciencia y la Tecnología (FECYT); Agencia Estatal de Investigación (España); Ministerio de Ciencia e Innovación; Consejo Superior de Investigaciones Científicas; Universidad de León; Instituto de Ganadería de Montaña (IGM, CSIC-ULE); Cátedra de Cultura Científica de la Universidad del País Vasco/ Euskal Herriko Unibertsitatea (UPV/EHU); Delegación del CSIC en Castilla y León; Unidade de Divulgación Científica e Cultural - Universidade da Coruña; Academia de la Llingua Asturiana; Casa Árabe; Alliance Française de Gijón; University of California-Davis; Teagasc; CSIC-Representación Illes Balears; Balearic Islands Coastal Observing and Forecasting System (SOCIB); Instituto de Física Interdisciplinar y Sistemas Complejos (IFISC, CSIC-UIB); Casa de la Ciència de Valencia (CSIC); Federación Española de Esperanto; Asociación Cultural Nogará Religada; Universidad de Zaragoza; Europa Laica; Museo Didáctico e Interactivo de Ciencias de la Vega Baja del Segura (MUDIC VBS-CV); Universidad Miguel Hernández; PuraVida Software.Mujeres con Ciencia; Asociaţia Secular-Umanistă din România; Instituto Geológico y Minero de España (IGME); Centro de Biología Molecular Severo Ochoa (CSIC-UAM); Asociación Española para el Avance de la Ciencia (AEAC); Centro de Investigación del Cáncer (CIC, CSIC-USAL); Discapacitodos; Universitat de les Illes Balears (UIB); Escuela de Estudios Hispano-americanos (CSIC); PRISMA – Asociación para la diversidad afectivo-sexual y de género en ciencia, tecnología e innovación; Instituto de Recursos Naturales y Agrobiología de Salamanca (IRNASA, CSIC); Círculo Escéptico; Civiencia; Universidad Autónoma de Madrid; Escuela de Estudios Árabes (CSIC); Evento Ciencia.Peer reviewe
    corecore