Màquina de vectors de suport i aplicació a un problema d’anàlisi d’àudio

Treballs Finals de Grau de Matemàtiques, Facultat de Matemàtiques, Universitat de Barcelona, Any: 2016, Director: Oriol Pujol VilaThe present work aims to find a mathematical model for classifying musical instruments from their timbres, so that we can use it for building an Android application which is able to classify a recorded instrument efficiently. To do so, we train a support vector machine with samples of such an instrument spectra as vectors, in order to obtain a pattern that let us classify new samples of these instruments

Single-pulsed supercontiuum generation in millimeter pieces of a birefringent microstructured silica fiber under femtosecond laser injection

Projecte fet en col.laboració amb l'ICFO (Institut de Ciències Fotòniques)Microstructured optical bers (MOF) are a new generation of optical bers that have a huge exibility on choosing the location of the zero dispersion wavelength, ZD which can be chosen to be very close to the visible and even in the visible, allowing soliton propagation in the near infrared. Moreover, the nonlinearity of silica with femtosecond radiation produces a broadening of the spectra, which is called supercontinuum (SC), due to several nonlinear e ects, as self phase modulation (SPM), cross phase modulation (XPM), dispersive wave generation and stimulated Raman scattering. I focused my work on the study of visible dispersive waves generated when a special phase matching condition between initial input pulse and some wave in the normal dispersion regime is ful lled

Methodological analysis about the potential avoidability of motor vehicles colliding against pedestrians in urban areas

The main motivation of the authors of this article is to establish a rigorous definition of the potential capacity that a motor vehicle driver has to avoid a collision against a pedestrian. Henceforth we will call this capacity avoidability. To calculate the avoidability, it is necessary to analyze time, distance and itinerary, initial position of the pedestrian when exposed to the risk, initial speed; theoretical maximum speed developed by the vehicle and road limit speed; the driver’s reaction time and the influence of the environment; and the interrelation of the initial positions of vehicle and pedestrian with respect to the transversal axis of the road. The definition, categorized by variables, of a driver’s ability to avoid run over a pedestrian in an urban area has an evident usefulness: it allows knowing the influence of the initial speed of a vehicle as an isolated variable and the importance of the road limit speed in the ability to prevent an accident.Postprint (published version

Translation and adaptation of terror: Two books for children and teenagers on 9/11 15TH anniversary

[EN] After the 9/11 attacks to the Twin Towers, the literary world witnessed the publication of a huge and varied quantity of books for children and teenagers, from picture books to more traditional texts, all of them illustrating an event which would become a turning point in world’s history and set its course towards a new world order. Fifteen years on, there is a young generation quite unaware of the events, even questioning that they really happened and were not part of a Hollywood disaster movie. Authors themselves wonder if the memories they hold have not already become but blurred images of that day. It is the aim of this paper to show how literature translates and adapts the events of that September morning to those who were not yet born or too young to understand the abrupt end of the past century[ES] La literatura destinada a un público infantil y juvenil tras los atentados del 11-S fue muy numerosa y diversa. Tanto los más pequeños, a través del álbum ilustrado, como los adolescentes de la primera década del siglo XXI, tuvieron acceso directo a multitud de textos que plasmaban uno de los acontecimientos que marcaría un antes y un después y señalaría el comienzo de un nuevo orden mundial. Quince años más tarde, nos encontramos ante una generación que no fue testigo directo de la caída de las torres y todo lo que con ellas desapareció, e incluso se cuestiona la realidad del suceso debido a la distancia temporal y puede llegar a asimilarlo a una de esas grandes producciones cinematográficas sobre catástrofes. Los propios autores se preguntan si aquellos recuerdos que un día fueron tan vívidos no estarán perdiendo nitidez en sus mentes. Es el propósito de este artículo mostrar cómo la literatura trata de traducir y adaptar el terror de una mañana de septiembre a los jóvenes que no presenciaron el abrupto final del siglo XX

Efecte filtre d'espín en complexos de Fe

En aquest article es presenta un efecte filtre d'espín d'àmbit unimolecular sota condicions de corrent polaritzat. En ell demostrem com en capturar una molècula d'un complex thermal spin-crossover de Fe entre dos elèctrodes, quan un d'ells és o bé a o bé b polaritzat, el darrer cas presenta una conductància com a mínim cent vegades superior respecte al primer. Aquesta és la primera vegada que s'ha pogut estudiar experimentalment un fenomen de filtratge d'espín a temperatura ambient.In this article a single-molecule spin-filter effect under polarized current conditions is presented. We demonstrate that, on capturing a molecule with a Fe thermal spin-crossover complex between two electrodes, when one of these is either a or b polarized, the b polarized electrode is at least one hundred times more conductive than the a electrode. This is the first time that it has been possible to study a spin-filter phenomenon at room temperature conditions

El Currículum como Desarrollo de Procesos Cognitivos y Afectivos

Los elementos básicos del currículum que siempre han existido son las capacidades y valores, los contenidos y los métodos / procedimientos. Según se organicen éstos el modelo de Escuela es diferente. La Escuela Clásica convierte los contenidos en objetivos y la Escuela Activa los métodos en objetivos. Hablar de enseñanza centrada en procesos, en este contexto, es imposible. Por el contrario afirmamos, en el marco de las Reformas Educativas actuales que las capacidades y valores se desarrollan por medio de contenidos y métodos. Y ello nos lleva a identificar las actividades como estrategias de aprendizaje, centradas en el sujeto que aprende y orientadas al desarrollo de procesos cognitivos (capacidades, destrezas y habilidades) y afectivos (valores y actitudes). Desde este nuevo paradigma socio – cognitivo hablamos del aprender a aprender para desarrollar el potencial de aprendizaje cognitivo y afectivo de los aprendices. La enseñanza centrada en procesos identifica al profesor como mediador del aprendizaje y mediador de la cultura social

Generalized optimal paths and weight distributions revealed through the large deviations of random walks on networks

Numerous problems of both theoretical and practical interest are related to finding shortest (or otherwise optimal) paths in networks, frequently in the presence of some obstacles or constraints. A somewhat related class of problems focuses on finding optimal distributions of weights which, for a given connection topology, maximize some kind of flow or minimize a given cost function. We show that both sets of problems can be approached through an analysis of the large-deviation functions of random walks. Specifically, a study of ensembles of trajectories allows us to find optimal paths, or design optimal weighted networks, by means of an auxiliary stochastic process (the generalized Doob transform). The paths are not limited to shortest paths, and the weights must not necessarily optimize a given function. Paths and weights can in fact be tailored to a given statistics of a time-integrated observable, which may be an activity or current, or local functions marking the passing of the random walker through a given node or link. We illustrate this idea with an exploration of optimal paths in the presence of obstacles, and networks that optimize flows under constraints on local observables.We thank Juan P. Garrahan, from whom we have learned much about the thermodynamics-of-trajectories formalism used in this paper, for useful suggestions. We are also grateful to H. Touchette for reading the paper and helpful comments. C.P.E. acknowledges C. Giardinà and C. Giberti for insight-ful discussions. The research leading to these results has received funding from the European Union’s Horizon 2020 research and innovation program under Marie Sklodowska-Curie Cofund Programme Athenea3I Grant No. 754446; from the European Regional Development Fund, Junta de Andalucía-Consejería de Economía y Conocimiento, Grant No. A-FQM-175-UGR18; and from MINECO, Spain (Grant No. FIS2017-84151-P). We are grateful for the computing re-sources and related technical support provided by PROTEUS,the supercomputing center of Institute Carlos I in Granada, Spain; and by CRESCO/ENEAGRID High Performance Computing infrastructure and its staff [64], which is funded by ENEA, the Italian National Agency for New Technologies, Energy, and Sustainable Economic Development and by Italian and European research programs

El desarrollo de la televisión local en Vizcaya

En Vizcaya y más concretamente en el Área de Bilbao se concentra la mayor diversidad de medios de comunicación de la Autonomía. Entre ellos destacan las televisiones locales que surgen desde diversos lugares de la provincia impulsados por Ayuntamientos, personas relacionadas con el mundo de la comunicación y grupos empresariales como Local Media, Localia TV y Vocento. En el artículo se hace una mención histórica de las televisiones locales atendiendo aspectos como: origen, promotores, cobertura geográfica, financiación y programación.specifically in the area of Bilbao. Amongst these media we underline the importance of the local television stations established by the town councils, people involved in the communication world and entrepreneurial groups like Local Media, Localia TV and Vocento. In this article we research the historical development of them, especially aspects like the origin, promoters, geographical cover, finance and programs

Forensic Psychological Evaluation in cases of Gender-Based Violence. Common errors and proposals for improvement

Este trabajo consiste en una “revisión de campo” y una recopilación de errores habituales detectados en evaluaciones psicológico-forenses en casos de violencia de género. A lo largo de nuestra experiencia profesional como psicólogos forenses y en nuestra práctica habitual encontramos dictámenes e informes en este ámbito que adolecen, en muchos casos, de rigor metodológico, dejando patente escaso conocimiento sobre la violencia de género, manifestaciones, evolución, victimización y consecuencias, llegando a interpretaciones y conclusiones periciales, cuanto menos, inexactas. Todo ello pudiera provocar no solo efectos de victimización secundaria sino que, además, los informes periciales no cumplirían realmente con su función de auxilio judicial. La propia exposición de errores evaluativos y de interpretación conlleva inherentemente diferentes propuestas de mejora.This work consists in a “field review” and a common mistakes compilation detected in psychological-forensic assessments in events of gender-based violence. In our professional experience being forensic psychologist and our daily job, we have found opinions and reports that, in many cases, suffer from methodological rigor, restricting the knowledge of intimate partner violence, their manifestations, evolution, victimization and consequences, leading to inaccurate and iatrogenic interpretations and conclusions. The evaluative mistakes detected will determine recommendations and expert discussions that could not be real about these complicated affairs, that could cause not only secondary victimization effects in women and children but also the psychological expert reports will not fulfil their basic function of expert advice and legal aid. This explanation about interpretation and evaluative mistakes leads to different proposals of improvement, specialized training, the use of appropriate assessment protocols and to do expert, structured and adapted reports to judicial context