18,636 research outputs found

    On a heuristic point of view concerning the motion of matter. From random metric to Schroedinger equation

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    The motion of a particle is studied in a random space-time. It is assumed that the velocity is small enough for the non-relativistic approximation to be valid. The randomness of the metric induces a diffusion in coordinate space. Hence it is shown that the evolution of the probability density is given by Schroedinger equation.Comment: 13 pages, minor changes, publication reference give

    Real-space study of the growth of magnesium on ruthenium

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    The growth of magnesium on ruthenium has been studied by low-energy electron microscopy (LEEM) and scanning tunneling microscopy (STM). In LEEM, a layer-by-layer growth is observed except in the first monolayer, where the completion of the first layer in inferred by a clear peak in electron reflectivity. Desorption from the films is readily observable at 400 K. Real-space STM and low-energy electron diffraction confirm that sub-monolayer coverage presents a moir\'e pattern with a 1.2 nm periodicity, which evolves with further Mg deposition by compressing the Mg layer to a 2.2 nm periodicity. Layer-by-layer growth is followed in LEEM up to 10 ML. On films several ML thick a substantial density of stacking faults are observed by dark-field imaging on large terraces of the substrate, while screw dislocations appear in the stepped areas. The latter are suggested to result from the mismatch in heights of the Mg and Ru steps. Quantum size effect oscillations in the reflected LEEM intensity are observed as a function of thickness, indicating an abrupt Mg/Ru interface.Comment: 21 pages, 10 figure

    Do Natural Disasters Affect Human Capital? An Assessment Based on Existing Empirical Evidence

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    The last few years have seen a notable increase in the number of studies investigating the causes and effects of natural disasters in many dimensions. This paper seeks to review and assess available empirical evidence on the ex-post microeconomic effects of natural disasters on the accumulation of human capital, focusing on consumption, nutrition, education and health, including mental health. Three major findings come forward from this work. First, disasters appear to bring substantial damages to human capital, including death and destruction, and produce deleterious consequences on nutrition, education, health and many income-generating processes. Furthermore, some of these detrimental effects are both large and long-lasting. Second, there is a large degree of heterogeneity in the size – but not much in the direction – of the impacts on different socioeconomic groups. Yet, an empirical regularity across natural hazards is that the poorest carry the heaviest burden of the effects of disasters across different determinants and outcomes of human capital. Finally, although the occurrence of natural hazards is mostly out of control of authorities, there still is a significant room for policy action to minimize their impacts on the accumulation of human capital. We highlight the importance of flexible safety nets as well as the double critical role of accurate and reliable information to monitor risks and vulnerabilities, and identify the impacts and responses of households once they are hit by a disaster. The paper also lays out existing knowledge gaps, particularly in regard to the need of improving our understanding of the impacts of disasters on health outcomes, the mechanisms of transmission and the persistence of the effects in the long-run.natural disasters, human capital accumulation

    Estudio de un sistema de almacenamiento energético híbrido para vehículo eléctrico

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    Los sistemas de almacenamiento energético basados exclusivamente en baterías tienen la desventaja de que no pueden absorber mucha potencia en comparación con la energía para la cual son dimensionados. Para evitar este inconveniente, se recurre a la hibridación de sistemas de almacenamiento consistentes en un conjunto de baterías y un banco de capacitores, de tal manera que haciendo que la energía pueda fluir entre los distintos dispositivos de almacenamiento, se puede disponer de un sistema de almacenamiento eléctrico que combina alta capacidad energética y potencia de uso. En este trabajo se presenta una forma de hibridación de sistemas de almacenamiento energético, una estrategia para su gestión, y una herramienta de cålculo. Mediante esta herramienta de cålculo, se puede conocer el desempeño del sistema híbrido presentado en base a las características del propio sistema de almacenamiento y del vehículo, utilizando como escenario distintos ciclos de conducción homologados.Departamento de Ingeniería Energética y FluidomecånicaMåster en Ingeniería de Automoció

    GPR clutter amplitude processing to detect shallow geological targets

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    The analysis of clutter in A-scans produced by energy randomly scattered in some specific geological structures, provides information about changes in the shallow sedimentary geology. The A-scans are composed by the coherent energy received from reflections on electromagnetic discontinuities and the incoherent waves from the scattering in small heterogeneities. The reflected waves are attenuated as consequence of absorption, geometrical spreading and losses due to reflections and scattering. Therefore, the amplitude of those waves diminishes and at certain two-way travel times becomes on the same magnitude as the background noise in the radargram, mainly produced by the scattering. The amplitude of the mean background noise is higher when the dispersion of the energy increases. Then, the mean amplitude measured in a properly selected time window is a measurement of the amount of the scattered energy and, therefore, a measurement of the increase of scatterers in the ground. This paper presents a simple processing that allows determining the Mean Amplitude of Incoherent Energy (MAEI) for each A-scan, which is represented in front of the position of the trace. This procedure is tested in a field study, in a city built on a sedimentary basin. The basin is crossed by a large number of hidden subterranean streams and paleochannels. The sedimentary structures due to alluvial deposits produce an amount of the random backscattering of the energy that is measured in a time window. The results are compared along the entire radar line, allowing the location of streams and paleochannels. Numerical models were also used in order to compare the synthetic traces with the field radargrams and to test the proposed processing methodology. The results underscore the amount of the MAEI over the streams and also the existence of a surrounding zone where the amplitude is increasing from the average value to the maximum obtained over the structure. Simulations show that this zone does not correspond to any particular geological change but is consequence of the path of the antenna that receives the scattered energy before arriving to the alluvial depositsPeer ReviewedPostprint (published version

    Moral in Cervantes: From Judgments to cases in Los trabajos de Persiles y Sigismunda

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    El tratamiento de aspectos morales en la literatura de Cervantes es especialmente problemĂĄtico. Considerando que el Persiles es una de las obras de Cervantes que mĂĄs atenciĂłn crĂ­tica ha recibido al respecto, nos proponemos un acercamiento la visiĂłn y configuraciĂłn morales de la obra a partir del anĂĄlisis de las intervenciones del narrador y de la voz de los personajes. A travĂ©s de este mĂ©todo, estudiaremos la articulaciĂłn en la novela del esquema clĂĄsico sentencia-caso (generalidad-particularidad) para establecer conclusiones en relaciĂłn con la moralThe treatment of moral issues in Cervantes’s literature is particularly problematic. Taking into account that Persiles is one of the author’s works that has received most critical attention thereon, we propose an approach to the work’s moral vision and configuration based on the analysis of the narrator’s statements and the characters’ voices. By means of this method, we will study the articulation in the novel of the classical framework judgment-exemplum (generality- particularity) in order to reach conclusions with regards to moral

    QUONDAM, Amedeo: El discurso cortesano, Madrid, Ediciones Polifemo, 2013, ediciĂłn e introducciĂłn de Eduardo Torres Corominas, 462 pĂĄgs

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    Entrevista a Melchora Romanos, Directora del Instituto de Filología y Literaturas Hispánicas. “Dr. Amado Alonso”

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    Entrevista

    Lope y la tragedia “al estilo español”: Hacia "El castigo sin venganza”

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    First, this paper analyzes the common elements of the works called for Lope tragedia, in order to determine the characteristics that configure this genre in the production of our author. Second, we focus on the study of El castigo sin venganza to establish whether this work shares the key aspects of the genre tragedy compared with the rest of works analyzedEn primer lugar, este trabajo analiza los elementos comunes de aquellas obras a las que Lope denomina en algĂșn momento tragedia, para asĂ­ poder determinar cuĂĄles son las caracterĂ­sticas que configuran este gĂ©nero en la producciĂłn dramĂĄtica de nuestro autor. En segundo lugar, nos centramos en el estudio de El castigo sin venganza, para establecer en quĂ© medida comparte los aspectos fundamentales del gĂ©nero tragedia con el resto de obras analizada

    Desarrollo de las habilidades lectoras en base a un método fónico potenciado a través de técnicas de neuro didåctica

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    Every teacher has an image of successful teaching based on the application of teaching-learning methodologies that optimise the brain function of students. Therefore, to educate today's generations, impregnated by technology, we must resort to new motivating systems that awaken their curiosity and interest. In order to achieve quality teaching, it is necessary to innovate and understand how the human brain works. When teachers understand how the brain learns, processes and stores information, they can adapt their teaching style and influence their students' brain development and the way they learn. In this document the importance of applying neuro-didactics techniques in the classroom to ensure that students receive knowledge, manipulate them and participation in the teaching process is highlighted. To achieve this goal, an educational proposal has been designed focusing on group and individual linguistic interventions, in which sensory activities are developed/included, memory is worked on and students' stimuli and attention are captured, pupils learn to control emotions and negative behaviours, thinking routines are developed and the conscious use of non-verbal language is encouraged. This involves increasing students' phonic awareness which develops alongside the development of reading, speaking, writing and listening skills thanks to the procedure used to teach the Spanish language in an environment where English is both the environmental language and the vehicular language.Todo docente tiene una imagen de enseñanza exitosa basada en la aplicaciĂłn de metodologĂ­as de enseñanza-aprendizaje que optimicen el funcionamiento cerebral del alumnado. Por ello, para educar a las generaciones actuales, impregnadas por la tecnologĂ­a se debe recurrir a nuevos sistemas motivadores y que despierten su curiosidad e interĂ©s. Para lograr una enseñanza de calidad es necesario innovar y conocer cĂłmo funciona el cerebro humano. Cuando el o la docente entiende cĂłmo el cerebro aprende, procesa y almacena la informaciĂłn, puede adaptar su estilo de enseñanza e influirĂĄ en el desarrollo cerebral de su alumnado y en la manera en la que aprenden. En el presente trabajo destaco la importancia de aplicar la neuro-didĂĄctica en el aula para lograr que el alumnado reciba conocimientos, los manipulen y participen en sus procesos de enseñanza. Para ello, se ha realizado una propuesta educativa centrada en intervenciones lingĂŒĂ­sticas grupales e individuales, en las que se desarrollan/incluyen actividades sensoriales, se trabaja la memoria y se captan los estĂ­mulos y la atenciĂłn de los estudiantes, se aprende a controlar las emociones y las conductas negativas, se desarrollan rutinas de pensamiento y se fomenta el uso consciente del lenguaje no verbal. Esto supone el incremento en el alumnado de una conciencia fĂłnica que se desarrolla pareja al desarrollo de habilidades lectoras, orales, escritas y de escucha gracias al procedimiento utilizado para enseñar la lengua española en un entorno en el que la lengua inglesa es tanto la lengua ambiental como la lengua vehicular.Grado en EducaciĂłn Infanti
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