5,126 research outputs found

    La atención de los estudiantes durante la clase de educación física basada en el rendimiento académico

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    Attention is an important variable that can dictate the success and failure of an activity or task. This variable is characterized by the ability to direct cognitive resources to a given situation. The purpose of this research was to find patterns in the students’ attention profiles, according to their academic achievement, during the physical education class and in different sports. We used the ATEST-EF questionnaire (Petrica, 2010) in which students had to answer the question «What were you thinking the moment you heard the signal?» The study involved 156 students from the 3th cycle of basic education, aged between 12 and 16 years old ( = 14,7 ± 1,3) evaluated in four different sports taught in the discipline of physical education (athletics, gymnastics, basketball and football), and in four moments of the class. Considering our variables, we used Chi-Square and Kruskal-Wallis statistical tests. The results show that task attendance holdsthehighestpercentagevalues throughouttheclassinrelationtotheremainingcategories,regardlessoftheiracademicperformance and sport, but we observed that students with satisfactory and good academic performance have more stable values of attention regarding the students with less academic performance. We found statistical significance at the end of the class between students with good academic performance and affective attention, and among students with lower academic performance and attention to other things. Subsequently, we used the same classification to compare the profiles of attention among the four mentioned sports. We observed some patterns between team and individual sports, but did not find statistically differences, however the results suggest a positive relationship between attention and academic performance.La atención es una variable importante que puede dictar el éxito y el fracaso de una actividad o tarea. Esta variable se caracteriza por la capacidad de dirigir recursos cognitivos a una situación dada. El propósito de esta investigación fue encontrar patrones en los perfiles de atención de los estudiantes, de acuerdo con sus logros académicos, durante la clase de educación física y en diferentes deportes. Utilizamos el cuestionario ATEST-EF (Petrica, 2010) en el que los estudiantes tenían que responder la pregunta «Qué estaba pensando en el momento en que escuchó la señal?» En el estudio participaron 156 estudiantes del tercer ciclo de educación básica, con edades comprendidas entre 12 y 16 años (= 14,7 ± 1,3) evaluados en cuatro deportes diferentes que se imparten en la disciplina de educación física (atletismo, gimnasia, baloncesto y fútbol), y en cuatro momentos de la clase. Considerando nuestras variables, utilizamos las pruebas estadísticas Chi-Square y Kruskal-Wallis. Los resultados muestran que la asistencia a las tareas tiene los valores porcentuales más altos en toda la clase en relación con las categorías restantes, independientemente de su rendimiento académico y deporte, pero observamos que los estudiantes con un rendimiento académico satisfactorio y bueno tienen valores de atención más estables con respecto a los estudiantes con Menos rendimiento académico. Encontramos significación estadística al final de la clase entre estudiantes con buen rendimiento académico y atención afectiva, y entre estudiantes con bajo rendimiento académico y atención a otras cosas. Posteriormente, utilizamos la misma clasificación para comparar los perfiles de atención entre los cuatro deportes mencionados. Observamos algunos patrones entre el equipo y los deportes individuales, pero no encontramos diferencias estadísticas, sin embargo, los resultados sugieren una relación positiva entre la atención y el rendimiento académico.info:eu-repo/semantics/publishedVersio

    Microstructured transparent conductive metallic electrodes fabricated by colloidal lithography

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    This thesis focuses on the development and optimization of a technique known as self-assembly colloidal lithography (CL) to fabricate transparent conductive electrodes. These contacts are of utmost importance for high performance optoelectronic devices, such as thin film solar cells. As of this moment, indium tin oxide (ITO) is the preferred transparent conductive oxide (TCO), but to improve the cell efficiency new materials with lower sheet resistance and better optical properties should be used. Besides, ITO is relatively expensive, so alternative Earth-abundant materials are highly desired to improve the devices’ cost-effectiveness. Conductive metallic micro-meshes within two thin TCO layers were investigated to improve the sheet resistance while maintaining an anti-reflection coating (ARC) type layer. The meshes were fabricated by CL after studying the influence of the main process parameters: polystyrene sphere sizes, etching times, aluminum and silver for the mesh and indium zinc oxide (IZO) and aluminum zinc oxide (AZO) for the TCO layer were studied. The resulting contacts were analyzed through UV-VIS-NIR spectrophotometry, hall-effect, scanning electron microscopy (SEM) equipped with energy dispersive spectroscopy (EDS) and atomic force microscopy (AFM). The results showed that 1.6 μm precursor spheres etched for 150s were the most reliable to produce closely-packed structures and to obtain low sheet resistance, while 5 μm spheres etched for 120s showed the best optical performance over the UV-VIS-NIR range. The contacts which showed the best optical and electrical results were produced with silver and IZO: when produced with 1.6 μm spheres the contacts presented sheet resistances as low as 10.6 Ω/sq and transmittances up to 75 %, and when produced with 5 μm spheres obtained transmittance up to 85 % with sheet resistance of 121 Ω/sq. The results reveal that our innovative large-area micro-meshed metallic electrodes fabricated by CL can attain performances close to those off state-of-art ITO (10 Ω/sq for 80 % transmittance and 100 Ω/sq for 90 % transmittance), but with superior transmittance mainly in the near-infrared range. This can be highly interesting, for instance, for the intermediate electrodes in multi-terminal multi-junction solar cell architectures

    Supervised Topical Key Phrase Extraction of News Stories using Crowdsourcing, Light Filtering and Co-reference Normalization

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    Fast and effective automated indexing is critical for search and personalized services. Key phrases that consist of one or more words and represent the main concepts of the document are often used for the purpose of indexing. In this paper, we investigate the use of additional semantic features and pre-processing steps to improve automatic key phrase extraction. These features include the use of signal words and freebase categories. Some of these features lead to significant improvements in the accuracy of the results. We also experimented with 2 forms of document pre-processing that we call light filtering and co-reference normalization. Light filtering removes sentences from the document, which are judged peripheral to its main content. Co-reference normalization unifies several written forms of the same named entity into a unique form. We also needed a "Gold Standard" - a set of labeled documents for training and evaluation. While the subjective nature of key phrase selection precludes a true "Gold Standard", we used Amazon's Mechanical Turk service to obtain a useful approximation. Our data indicates that the biggest improvements in performance were due to shallow semantic features, news categories, and rhetorical signals (nDCG 78.47% vs. 68.93%). The inclusion of deeper semantic features such as Freebase sub-categories was not beneficial by itself, but in combination with pre-processing, did cause slight improvements in the nDCG scores.Comment: In 8th International Conference on Language Resources and Evaluation (LREC 2012

    Resistance to fatigue of self-healed concrete based on encapsulated polymer precursors

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    Moving cracks are often present in concrete structures and in those circumstances any self-healing technique for concrete must satisfy specific performance requirements, to guarantee its increased durability. These requirements include the capability of withstanding multiple cycles of crack movement without failing to keep healed cracks sealed. This paper shows early results from a testing protocol suggested by the authors to assess the performance of polymers as healing materials for moving cracks. Ultrasound (US) shear waves were used for continuous monitoring of small prismatic mortar specimens containing a single healed crack under a cyclic load. The maximum amplitude of US waves transmitted across healed cracks was correlated to the area effectively healed and the magnitude of crack movement. A decreasing trend of the maximum amplitude during cyclic loading was observed for strain levels on the polymer corresponding to 70% of its strain limit, but soundness at lower strain levels was confirmed after 300 cycles

    Interaction systems design and the protocol- and middleware-centred paradigms in distributed application development

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    This paper aims at demonstrating the benefits and importance of interaction systems design in the development of distributed applications. We position interaction systems design with respect to two paradigms that have influenced the design of distributed applications: the middleware-centred and the protocol-centred paradigm. We argue that interaction systems that support application-level interactions should be explicitly designed, using the externally observable behaviour of the interaction system as a starting point in interaction systems design. This practice has two main benefits: to promote a systematic design method, in which the correctness of the design of an interaction system can be assessed against its service specification; and, to shield the design of application parts that use the interaction system from choices in the design of the supporting interaction system
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