Utilización de la cámara plenóptica como sensor de frente de onda para óptica adaptiva en astrofísica

La Cámara Plenóptica es un concepto que proviene del campo de la fotografía computacional, y que surge como herramienta para capturar una cantidad aprovechable de muestras de la Función Plenóptica, o ¿Light Field¿. Esta función, de cuatro variables espaciales que recorren la apertura y el plano focal de un sistema óptico que genera imagen, constituye una descripción completa de la información disponible en el interior de dicho sistema, de la que la imagen es únicamente un caso particular. Por otro lado, la Óptica Adaptativa para compensación de la turbulencia atmosférica en la observación astrofísica se ha convertido en un objetivo irrenunciable cuando los telescopios han pasado a tener diámetros de decenas de metros. Los sensores convencionales como Shack-Hartmann, Curvatura y Pirámide, presentan problemas importantes a la hora de medir las diferencias de fase asociadas a la turbulencia atmosférica a partir de objetos extensos o cuando se pretende corregir de turbulencia atmosférica en un amplio campo visión, más allá del eje óptico. Tal y como se muestra en esta Tesis, la cámara plenóptica puede ser usada para medir la fase del frente de onda, con la ventaja añadida de contener a los citados sensores convencionales como casos particulares, y de manera casi natural resolver una gran parte de los problemas asociados al uso de los mismos. El trabajo realizado en esta Tesis resulta especialmente completo teniendo en cuenta que engloba simulaciones informáticas, pruebas de laboratorio, y observaciones reales en telescopio, todos ellos guardando entre sí una exquisita coherencia. Contiene además un estudio profundo de calibración de la Cámara Plenóptica, absolutamente indispensable para medir correctamente las diferencias de fase de frente de onda. Como principal resultado final cabe citar la introducción de un nuevo sensor de frente de onda para Óptica Adaptativa en Astrofísica, acompañado de un análisis exhaustivo de su uso en observaciones reales y de la comparación con los sensores convencionales de frente de onda. Además, se ha planificado un diseño sobre hardware electrónico especializado que garantice la medida de la fase del frente de onda, dentro del tiempo de estabilidad de la atmósfera, en los actuales y futuros telescopios de gran diámetro

Paulo Freire: Pedagogía del oprimido.

El siguiente Trabajo Final de Grado, es un proyecto de análisis de la teoría de Paulo Freire, más concretamente de “La pedagogía del oprimido” y de la influencia que esta manera de entender la sociedad y la vida en general tiene en la educación, explicando una breve biografía, contexto histórico, seguido de la importancia que este tiene en el desarrollo de la obra de Paulo Freire, incluyendo un análisis de una de sus obras más emblemáticas.The next final graduate work is a project of analysis of the theory of Paulo Freire, more specific, The Pedagogy of the oppressed, and the influence that this way understanding society and life and education. Explaining a little bibliography, historial context and importance it has in the devolpment of the work of Paulo Frere

Initial Conceptions in the Statistical Reasoning and Modeling Processes in Engineering Students

The cognitive view in educational psychology is considered one of the traditional perspectives for psychologists, who recognize that students may have different but identifiable conceptions of learning. The work aimed to compare initial conceptions of statistical modeling processes and levels of statistical reasoning in engineering students. The research had a qualitative approach with a multiple-case design. As a source of data collection, a questionnaire was designed and applied to 38 students taking the subject Probability and Statistics. The results and data analysis showed that none of the participants went through all the phases of statistical modeling, evidencing a low ability to establish relationships in the data and interconnect statistical concepts. Consequently, the students failed to reach the maximum level of statistical reasoning. The participants also identified difficulties in establishing coherent interpretations when making representations of statistical models such as frequency tables, graphs and measures of central tendency. Therefore, there is a need to continue developing research that provides theoretical foundations for the characterization of the modeling and statistical reasoning processes to improve the learning of statistics and probability in university students

Alcohol-related stimuli modulate functional connectivity during response inhibition in young binge drinkers

Binge drinking is a pattern of intermittent excessive alcohol consumption that is highly prevalent in young people. Neurocognitive dual-process models have described substance abuse and adolescence risk behaviours as the result of an imbalance between an overactivated affective-automatic system (related to motivational processing) and damaged and/or immature reflective system (related to cognitive control abilities). Previous studies have evaluated the reflective system of binge drinkers (BDs) through neutral response inhibition tasks and have reported anomalies in theta (4–8 Hz) and beta (12–30 Hz) bands. The present study aimed to investigate the influence of the motivational value of alcohol-related stimuli on brain functional networks devoted to response inhibition in young BDs. Sixty eight BDs and 78 control participants performed a beverage Go/NoGo task while undergoing electrophysiological recording. Whole cortical brain functional connectivity (FC) was evaluated during successful response inhibition trials (NoGo). BDs exhibited fast-beta and theta hyperconnectivity in regions related to cognitive control. These responses were modulated differently depending on the motivational content of the stimuli. The increased salience of alcohol-related stimuli may lead to overactivation of the affective-automatic system in BDs, and compensatory neural resources of the reflective system will thus be required during response inhibition. In BDs, inhibition of the response to alcohol stimuli may require higher theta FC to facilitate integration of information related to the task goal (withholding a response), while during inhibition of the response to no-alcoholic stimuli, higher fast-beta FC would allow to apply top-down inhibitory control of the information related to the prepotent responseFunding for this research was provided by the Plan Nacional Sobre Drogas (PNSD 2015/034) and Ministerio de Economía, Industria y Competitividad together with European Regional Development Fund (PSI2015-70525-P), Ministerio de Ciencia e Innovación (PID2020-113487RB-I00) and Xunta de Galicia (ED431C 2917/06). JBR was supported by the FPU program (FPU2015-03591) of the Spanish Ministry of Education, Culture and Sports. SSS was supported by a predoctoral fellowship from the Spanish Ministerio de Economía y Competitividad (BES-2016-076298).S

Avance en la caracterización de modelos didácticos para mejorar el razonamiento estadístico en estudiantes universitarios.

Tradicionalmente el estudiante de nivel universitario, tiene la concepción de que la estadística es una serie de fórmulas a seguir para el manejo de datos. Estas concepciones se evidencian en una forma de aprender de memoria, una serie de conceptos estadísticos ajenos al estudiante, en contraste con la elaboración de formas de interpretar, analizar y razonar estadísticamente. Los modelos didácticos bien elaborados pueden contribuir a mejorar esta problemática. El presente escrito tiene como intención, presentar avances en la revisión del estado del arte acerca de los constructos razonamiento estadístico y modelos didácticos, como una estrategia que contribuya en el diseño y realización de la investigación que tiene como propósito responder la pregunta de investigación: ¿Cómo los modelos didácticos mejoran los procesos de razonamiento estadístico en los estudiantes universitarios? Los resultados de la revisión de la literatura muestran claramente que hay dos vertientes acerca de la caracterización del razonamiento estadístico: la primera, la concepción acerca del razonamiento estadístico como formas o maneras de razonar estadísticamente y no como un proceso. Desde la mirada de otros investigadores, es un proceso de integración cognitiva, caracterizado por cinco niveles de razonamiento estadístico. Por su parte los modelos didácticos son categorizados de diferentes maneras

An instrumental puzzle: the modular integration of AOLI

The Adaptive Optics Lucky Imager, AOLI, is an instrument developed to deliver the highest spatial resolution ever obtained in the visible, 20 mas, from ground-based telescopes. In AOLI a new philosophy of instrumental prototyping has been applied, based on the modularization of the subsystems. This modular concept offers maximum flexibility regarding the instrument, telescope or the addition of future developments.Comment: 10 pages, 8 figures, Proc. SPIE 9908, Ground-based and Airborne Instrumentation for Astronomy VI, 99082Z (August 9, 2016

A Dynamic Equilibrium View of Caching Systems

In this paper, we present a simple analytical study of caching systems based on the idea of dynamic equilibrium of cache blocks, assuming the Independent Reference Model (IRM) of references. This method allows us to obtain simple closedform expressions for parameters that are usually excluded from cache studies, such as the mean number of reads or writes per cache block while in the cache. We finally present some simulation results in order to validate the analysis.Ministerio de Educación y Ciencia TIN2006-15617- C03-03Junta de Andalucía P06-TIC-229

Error adaptive tracking for mobile robots

In mobile robots it is usual that the desired trajectory is memorized or previously generated. When following a trajectory, there are several possibilities attending to the way in which the actual robot state can be related with the whole trajectory. One of them is the extension of the servosystem approach, usually called "trajectory tracking". This is the only possibility if we need strict temporal deterministic requirements. But if not, other possibilities appear. One of them is called "path following", where the path's point to track is the "nearest" (under several conditions) to the actual robot's position. In this paper we present another method suitable for nondeterministic systems, which we may call "error adaptive tracking", because the tracking pace adapts to the errors. Its benefits and advantages are identified. Afterwards, we determine how to construct this method and we apply it to the case of SIRIUS, an advanced wheelchair. Then a control law that ensures asymptotic stability is extracted using the second Lyapunov method and under the error adaptive tracking approach. Finally, we show the benefits of the new method, comparing it with the trajectory tracking approach.Ministerio de Ciencia y Tecnología TIC-2000-0087-P4-

Laboratory and telescope demonstration of the TP3-WFS for the adaptive optics segment of AOLI

AOLI (Adaptive Optics Lucky Imager) is a state-of-art instrument that combines adaptive optics (AO) and lucky imaging (LI) with the objective of obtaining diffraction limited images in visible wavelength at mid- and big-size ground-based telescopes. The key innovation of AOLI is the development and use of the new TP3-WFS (Two Pupil Plane PositionsWavefront Sensor). The TP3-WFS, working in visible band, represents an advance over classical wavefront sensors such as the Shack-Hartmann WFS (SH-WFS) because it can theoretically use fainter natural reference stars, which would ultimately provide better sky coverages to AO instruments using this newer sensor. This paper describes the software, algorithms and procedures that enabled AOLI to become the first astronomical instrument performing real-time adaptive optics corrections in a telescope with this new type of WFS, including the first control-related results at the William Herschel Telescope (WHT)This work was supported by the Spanish Ministry of Economy under the projects AYA2011-29024, ESP2014-56869-C2-2-P, ESP2015-69020-C2-2-R and DPI2015-66458-C2-2-R, by project 15345/PI/10 from the Fundación Séneca, by the Spanish Ministry of Education under the grant FPU12/05573, by project ST/K002368/1 from the Science and Technology Facilities Council and by ERDF funds from the European Commission. The results presented in this paper are based on observations made with the William Herschel Telescope operated on the island of La Palma by the Isaac Newton Group in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofísica de Canarias. Special thanks go to Lara Monteagudo and Marcos Pellejero for their timely contributions

Dimensiones de la reputación corporativa

Los directivos de las empresas reconocen la importancia adquirida por la reputación corporativa considerada, por muchos, como el activo que les agrega valor por lo que debe de ser gestionada eficientemente y de manera sostenible en el tiempo. En la literatura revisada se ha encontrado que algunos autores resaltan la incertidumbre de los directivos para determinar las dimensiones de la reputación corporativa debido a las convergencias y divergencias que tienen los autores acerca de la manera de identificar las que deben aplicarse en sus respectivas empresas. Del análisis de esta literatura, se desprende que no existe consenso para determinar una receta que defina las dimensiones con las que se pueda medir la reputación corporativa de las empresas, motivo por el cual, sobre la base de las convergencias encontradas, se propone en la presente tesis una guía flexible que ayude a los directivos a identificarlas y gestionarlas. La guía desarrollada propone realizar, inicialmente, un análisis del sector al cual pertenece la empresa, lo cual permitirá conocer su actividad principal, el contexto en el que se desenvuelve y el entorno al que está expuesto. Posteriormente se identificarán los grupos de interés más representativos y, finalmente, una vez definidos, se determinarán las dimensiones de la reputación corporativa tomando ahora, como base, los grupos de interés. Adicionalmente, debe considerarse el tiempo que la empresa lleva operando, ya que esto afecta las perspectivas a futuro; en general, mientras más años haya tenido la empresa un comportamiento consistente o similar más fácil es pensar que lo seguirá haciendo en los años venideros.Company managers recognize the importance gained by the corporate reputation, considered by many as the asset which gives them added value for which it must be managed efficiently and, in time, in a sustained manner. In the literature that was reviewed it was found that some authors highlight the uncertainty of managers in determining the dimensions of the corporate reputation due to the convergences and divergences that the authors have about the way to identify the ones that must be applied in their respective companies. From the analysis of this literature, it follows that there is no consensus in determining a recipe that defines the dimensions with which to measure the corporate reputation of companies. This is why a flexible instrument has been developed, in order to help managers identifying and managing their companies’ corporate reputation. The stated instrument consists in, initially, performing an analysis of the sector in which the company belongs and thus knowing its principal activity, the context in which it develops and the environment in which it is exposed. Later, the more representative interest groups will be identified and finally, the dimensions of the corporate reputation will be determined taking into account now, as a base, the interest groups. Additionally, the long term has also being considered, since a company future behavior is expected regarding its past actions. Therefore, the amount of years that any company has been around is taking in consideration, benefiting those that has behaved consistently for long periods of time.Tesi