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Estereotips a secundària. Proposta de dinàmiques per incrementar la presència femenina a l'àrea de Tecnologia als centres d'educació secundària

  • Gómez Cordellat, Victòria
Aquest Treball Final de Màster té com a objectiu ajudar a reduir la diferència de gènere a Tecnologia de 4t d'ESO. Per aquest fi, es proposen didàctiques educatives innovadores per implantar als centres de secundària. Per arribar a aquest objectiu, es realitza una enquesta als centres de secundària, públics i concertats, de Catalunya i a més, per tal de garantir el caràcter innovador de les propostes, s'estudien les polítiques d'Igualtat de la UPC. Els resultats d'aquest estudi revelen que a Tecnologia de 4t d'ESO ja existeix una diferència de gènere que concorda amb la diferència que hi ha als estudis superiors. Dels centres adherits a l'estudi, només el 8% d'ells té un grup de Tecnologia en el que hi ha més noies que nois. A més, les dades mostren que la distribució de noies i nois dintre del grup se situa en 1 noia cada 3 nois. De l'enquesta també es desprèn que la principal causa d'aquest problema radica en la personalitat pròpia de l'alumne. Com a solució principal al biaix de gènere, els enquestats assenyalen que cal un canvi en la matèria i, a més, comenten que caldria començar les mesures correctores a Infantil. Un cop estudiades totes aquestes variables, tant l'enquesta com les polítiques d'igualtat de la UPC, es proposa realitzar una revista tecnològica que ajudarà a reduir la diferència de gènere a Tecnologia de 4t d'ESO.

Seawater intrusion barrier in the deltaic Llobregat aquifer (Barcelona, Spain): performance and pilot phase results

  • Ortuño Gobern, Felip
  • Molinero Huguet, Jorge José
  • Custodio Gimena, Emilio
  • Juárez Álvarez, Iker
  • Garrido, Teresa
  • Fraile, Josep
The main aquifer of the Llobregat Delta (Barcelona, Spain) is affected by seawater intrusion processes since the 1960s. The Catalan Water Agency is currently promoting several actions of artificial aquifer recharge, including the construction of a positive hydraulic barrier in order to stop the advance of the seawater intrusion. Such a positive hydraulic barrier works by injecting reclaimed water in 14 wells. This is the first time that a project of this type is performed in Spain and it is also pioneer in Europe. The positive hydraulic barrier produces the rise of the groundwater head near the coast in order to halt seawater penetration inland. The injected reclaimed water comes from the WWTP of the Baix Llobregat after passing through several treatments (ultrafiltration, reverses osmosis and disinfection). The pilot phase of the project has been working during the last 3 years. Hydrogeochemical analyses show highly positive results and is effectively reducing the salt water intrusion process. Substantial improvement of the groundwater quality has been observed in wells surrounding the injection points and no clogging has appeared. Currently the whole planned project is under operation.

Ectopic beats arise from micro-reentries near infarct regions in simulations of a patient-specific heart model

  • sachetto Oliveira, Rafael
  • Alonso Muñoz, Sergio
  • Otaviano Campos, Fernando
  • Martins Rocha, Bernardo
  • Filipe Fernandes, João
  • Kuehne, Titus
  • Weber dos Santos, Rodrigo
Ectopic beats are known to be involved in the initiation of a variety of cardiac arrhythmias. Although their location may vary, ectopic excitations have been found to originate from infarct areas, regions of micro-fibrosis and other heterogeneous tissues. However, the underlying mechanisms that link ectopic foci to heterogeneous tissues have yet to be fully understood. In this work, we investigate the mechanism of micro-reentry that leads to the generation of ectopic beats near infarct areas using a patient-specific heart model. The patient-specific geometrical model of the heart, including scar and peri-infarct zones, is obtained through magnetic resonance imaging (MRI). The infarct region is composed of ischemic myocytes and non-conducting cells (fibrosis, for instance). Electrophysiology is captured using an established cardiac myocyte model of the human ventricle modified to describe ischemia. The simulation results clearly reveal that ectopic beats emerge from micro-reentries that are sustained by the heterogeneous structure of the infarct regions. Because microscopic information about the heterogeneous structure of the infarct regions is not available, Monte-Carlo simulations are used to identify the probabilities of an infarct region to behave as an ectopic focus for different levels of ischemia and different percentages of non-conducting cells. From the proposed model, it is observed that ectopic beats are generated when a percentage of non-conducting cells is near a topological metric known as the percolation threshold. Although the mechanism for micro-reentries was proposed half a century ago to be a source of ectopic beats or premature ventricular contractions during myocardial infarction, the present study is the first to reproduce this mechanism in-silico using patient-specific data., Peer Reviewed

El sonido como herramienta narrativa en los videojuegos

  • Berenguer Ibar, Eric
L'objecte d'aquest treball es basa en la investigació del so com a element narratiu en els videojocs. S'estudien i es contraposen diferents teories prèvies a aquesta, s'analitzen diferents referents tenint en compte el marc teòric i es posa en pràctica en un projecte un videojoc real. S'obtenen els resultats de la investigació i del cas pràctic, i es conclou de quina manera es pot interpretar el discurs narratiu en un videojoc.

Numerical simulation of the undrained stability of slopes in anisotropic fine-grained soils

  • Conesa, Sergi
  • Mánica Malcom, Miguel Ángel
  • Gens Solé, Antonio
  • Huang, Y.
This is an Accepted Manuscript of an article published by Taylor & Francis Group in Geomechanics and geoengineering on 2019, available online at: http://www.tandfonline.com/10.1080/17486025.2018.1490460, The undrained stability of slopes in anisotropic fine-grained soils is studied in this paper using the finite element method (FEM). A constitutive model is presented, able to account for the observed variation of undrained strength with loading direction. The model is able to encompass the different strength distributions observed in normally, slightly overconsolidated and heavily overconsolidated soils. A series of stability analyses have been performed to explore the effect of the type of undrained strength anisotropy on the stability and failure mechanisms of slopes of different inclinations. In addition, a real case study of the failure of an underwater slope is analysed with the numerical approach presented. It suggests that, by considering undrained strength anisotropy, the failure can be satisfactorily explained., Peer Reviewed

El Año de la Astronomía

  • Barceló Garcia, Miquel

Robust admittance shaping approach to grid current harmonic attenuation and resonance damping

  • Cóbreces Álvarez, Santiago
  • Wang, Xiongfei
  • Pérez Serrano, Jorge
  • Griñó Cubero, Robert
  • Blaabjerg, Frede
© 2018 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting /republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works, This paper presents a novel grid current control of a grid-connected voltage source converter with an LCL filter. The proposed control method uses an H 8 synthesis method to shape the input admittance of the converter, to track a given current reference, and/or to limit the controller actuation at different frequency ranges. The converter admittance is shaped, both in magnitude and phase, following a model reference defined by the designer in the frequency domain. By specifying a low admittance magnitude reference, the optimization algorithm will obtain a controller that actively damp the filter resonance and attenuate/reject the grid voltage oscillations, either in a wide frequency range or concentrated at the main harmonic frequencies. Additionally, the proposed controller design methodology takes advantage of its admittance phase shaping capability to improve the system robustness in front of grid uncertainties and minimizing converter impact over grid stability due to its positive-real nature. The synthesized controller only measures the grid current and voltage to achieve the aforementioned results, reducing the number of sensors (and their associated cost) required for its implementation. Experimental results illustrate the correct behavior of the closedloop system with the designed controller in time and frequency domain.

Seguimos en Uganda

  • Barceló Garcia, Miquel

Long-range transport of Saharan dust to northern Europe: The 11-16 October 2001 outbreak observed with EARLINET

  • Ansmann, Albert
  • Bösenberg, Jens
  • Chaikovsky, Anatoli
  • Comerón Tejero, Adolfo
  • Eckhardt, Sabine
  • Eixmann, Ronald
  • Freudenthaler, Volker
  • Ginoux, Paul
  • Komguem, Leonce
  • Linné, Holger
  • López Márquez, Miguel Ángel
  • Matthias, Volker
  • Mattis, Ina
  • Mitev, Valentin
The spread of mineral particles over southwestern, western, and central Europe resulting from a strong Saharan dust outbreak in October 2001 was observed at 10 stations of the European Aerosol Research Lidar Network (EARLINET). For the first time, an optically dense desert dust plume over Europe was characterized coherently with high vertical resolution on a continental scale. The main layer was located above the boundary layer (above 1-km height above sea level (asl)) up to 3–5-km height, and traces of dust particles reached heights of 7–8 km. The particle optical depth typically ranged from 0.1 to 0.5 above 1-km height asl at the wavelength of 532 nm, and maximum values close to 0.8 were found over northern Germany. The lidar observations are in qualitative agreement with values of optical depth derived from Total Ozone Mapping Spectrometer (TOMS) data. Ten-day backward trajectories clearly indicated the Sahara as the source region of the particles and revealed that the dust layer observed, e.g., over Belsk, Poland, crossed the EARLINET site Aberystwyth, UK, and southern Scandinavia 24–48 hours before. Lidar-derived particle depolarization ratios, backscatter- and extinction-related A ° ngstro¨m exponents, and extinction-to-backscatter ratios mainly ranged from 15 to 25%, 0.5 to 0.5, and 40–80 sr, respectively, within the lofted dust plumes. A few atmospheric model calculations are presented showing the dust concentration over Europe. The simulations were found to be consistent with the network observations.

On the zero- and first-order interpolation in synthesized wave for testing purposes

  • Lozano Nieto, Alberto
  • Rosell Ferrer, Francisco Javier
  • Pallàs Areny, Ramon
This paper deals with the quality requirements of synthesized sine waves reconstructed through a zero- or first- order hold for testing purposes, in particular when a switching demodulator is used. In this case, the interest is to have great spectral purity near the carrier rather than in all of the band. We show that the best method to obtain great spectral purity in the frequency band close to the synthesized frequency is by using zero-order hold instead of a first-order hold. Results show that even though a first-order hold implies a decrease of total harmonic amplitude distortion (THD), the measured spurious harmonics are kept lower or equal when using a zero-order hold in the 15 closest components. We conclude that in testing applications a zero-order hold (in spite of its greater THD) yields better results., Peer Reviewed

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