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Eficiència energètica pel Desenvolupament Sostenible

  • Amo Hernández, Alejandro
Som una societat totalment ineficient, tenim molta energia barata per introduir al balanç energètic del medi i fer-lo més gran energèticament i no físicament. Aquesta energia contamina el medi en totes les formes que se’n deriven, l’avenç tecnològic implica increment del consum d’energia i per tant una necessitat d’afegir més energia. Contaminació Eespecífica Contaminació E'1 E1 E2 E'2 La Dintre de la cultura de l’ “un sol ús”, l’ “stand by” dels electrodomèstics, les retencions de tràfic, els correus brossa, les llums incandescents, els embolcalls excessius i milers d’altres exemples, l’eficiència és una anècdota. En un món regulat pels costos/beneficis, l’eficiència depèn que el resultat de la següent equació sigui positiu: Beneficis – (Cost Inversió Eficiència + Cost Producte) = Resultats Necessitem buscar la màxima eficiència en tots els aspectes per tal d’apropar-nos a una societat sostenible. Actualment i gestionant correctament les tecnologies de que disposem, podem ser més eficients i s’ha de planificar les futures per tal que acompleixin aquesta filosofia. L’eficiència és la forma de quantificar la sostenibilitat. En l’article es donarà una sèrie de recomanacions per avançar en la sostenibilitat, des d’aspectes que a dia d’avui ja es podrien ficar en pràctica a d’altres que; per la investigació que necessiten, són a llarg termini. S’enfocarà tant a nivell tècnic com social, d’educació i formació energètica; tot indicant cinc punts bàsics a seguir com són 1. Identificació i avaluació de la sostenibilitat, 2. Conscienciació, 3. Educació, 4. Inducció i Obligatorietat, 5. Investigació, Peer Reviewed
Proyecto:


Ecosistemes sota stress

  • Margalef López, Ramon
Peer Reviewed
Proyecto:


Projet Gaia 3: Résidence Universitaire International du Futur

  • Bencomo Garcia, Oscar
Dans le projet de construction de la résidence universitaire internationale du futur, les élèves du EEIGM ont pris le défi de nous adapter à un projet tellement différent qu’eux à que nous sommes habitués. Pour cela, l’intention à l’heure de confronter le projet est d’essayer de mettre en pratique tous les techniques possibles que nous avons appris pendant les études d’ingénierie. Nous avons aussi la volonté de sortir de la zone de confort, et essayer d’aller toujours plus loin et parcourir des champs qui peuvent être outils pour notre futur mais que nous n’avons pas vu pendant nôtres études. Nous confrontons ce projet aussi avec la volonté de créer une équipe forte, unie et avec un objectif commun. Nous voulons utiliser des techniques de management et communication appris en la lecture des différents documents (livres, articles, etc.) au cours des années, en tenant en compte les limitations du projet et les différences culturelles dans le group. Pour nous, ce projet c’est une grande opportunité pour apprendre comment manager un projet assez long et avec une groupe assez grande et varié. Aucun des élèves de l’EEIGM a jamais travaillé en un projet semblable. Dans ce document, les élèves de l’EEIGM présentent son travail réalisé. Le lecteur pourra apprécier un champ de travail très ample, dès l’étude des matériaux jusqu'à l’utilisation de techniques modernes de marketing.
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Circuit modeling of a MEMS varactor including dielectric charging dynamics

  • Giounanlis, Panagiotis
  • Andrade Miceli, Dennis
  • Gorreta Mariné, Sergio
  • Pons Nin, Joan
  • Domínguez Pumar, Manuel
  • Blokhina, Elena
Electrical models for MEMS varactors including the effect of dielectric charging dynamics are not available in commercial circuit simulators. In this paper a circuit model using lumped ideal elements available in the Cadence libraries and a basic Verilog-A model, has been implemented. The model has been used to simulate the dielectric charging in function of time and its effects over the MEMS capacitance value., Peer Reviewed
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Optimal harmonic response in a confined Bödewadt boundary layer flow

  • Younghae, Do
  • Lopez, Juan M.
  • Marqués Truyol, Francisco
The Bödewadt boundary layer flow on the stationary bottom end wall of a finite rotating cylinder is very sensitive to perturbations and noise. Axisymmetric radial waves propagating inward have been observed experimentally and numerically before the appearance of spiral three-dimensional instabilities. In this study, the sensitivity and response of the finite Bödewadt flow to a harmonic modulation of the rotation rate are analyzed. A comprehensive exploration of response to variations in the amplitude and frequency of the forcing has been carried out. There are sharply delineated linear- and nonlinear-response regimes, with a sharp transition between them at moderate amplitudes. The periodic forcing leads to a steady-streaming flow, even in the linear-response regime, and to a period-doubling bifurcation in the nonlinear regime. Frequency response curves at different forcing amplitudes over a wide range of frequencies have been computed and used to identify the frequency band that excites the axisymmetric radial waves and the forcing frequency that elicits the strongest response. Finally, we have shown that the axisymmetric waves always decay to the steady basic state when the harmonic modulation is suppressed, and conclude that the experimentally observed persistent circular waves are not self-sustained.
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In vivo, non-invasive characterization of human bone by hybrid broadband (600-1200 nm) diffuse optical and correlation spectroscopies

  • Konugolu Venkata Sekar, Sanathana
  • Pagliazzi, Marco
  • Negredo Puigmal, Eugènia
  • Martelli, Fabrizio
  • Farina, Andrea
  • Dalla Mora, Alberto
  • Lindner, Claus
  • Farzam, Parisa
  • Pérez Álvarez, Nuria
  • Puig, Jordi
  • Taroni, Paola
  • Pifferi, Antonio
  • Durduran, Turgut
Non-invasive in vivo diffuse optical characterization of human bone opens a new possibility of diagnosing bone related pathologies. We present an in vivo characterization performed on seventeen healthy subjects at six different superficial bone locations: radius distal, radius proximal, ulna distal, ulna proximal, trochanter and calcaneus. A tailored diffuse optical protocol for high penetration depth combined with the rather superficial nature of considered tissues ensured the effective probing of the bone tissue. Measurements were performed using a broadband system for Time-Resolved Diffuse Optical Spectroscopy (TRS) to assess mean absorption and reduced scattering spectra in the 600–1200 nm range and Diffuse Correlation Spectroscopy (DCS) to monitor microvascular blood flow. Significant variations among tissue constituents were found between different locations; with radius distal rich of collagen, suggesting it as a prominent location for bone related measurements, and calcaneus bone having highest blood flow among the body locations being considered. By using TRS and DCS together, we are able to probe the perfusion and oxygen consumption of the tissue without any contrast agents. Therefore, we predict that these methods will be able to evaluate the impairment of the oxygen metabolism of the bone at the point-of-care., Peer Reviewed
Proyecto:


El nivel medio del mar a escala estacional, anual y decadal. Implicaciones para la ingeniería de puertos y costas

  • Simic Sans, Marcos Miroslav
El presente estudio recoge un análisis sobre el nivel del mar a diferentes escalas temporales. Se correlaciona con las variables atmosféricas más significativas y se elabora un modelo de predicción. Se discute la aparente tendencia menguante del nivel del mar en el Mediterráneo occidental, así como hipotéticas afecciones sobre las diferentes tipologías de infraestructura marítima y portuaria, producto de la extrapolación de las tendencias observadas
Proyecto:


Criterion for the electrical resonance stability of offshore wind power plants connected through HVDC links

  • Cheah Mañé, Marc
  • Sainz Sapera, Luis
  • Liang, Jun
  • Jenkins, Nicholas
  • Ugalde Loo, Carlos E.
© 2017 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., Electrical resonances may compromise the stability of HVDC-connected offshore wind power plants (OWPPs). In particular, an offshore HVDC converter can reduce the damping of an OWPP at low-frequency series resonances, leading to the system instability. The interaction between offshore HVDC converter control and electrical resonances of offshore grids is analyzed in this paper. An impedance-based representation of an OWPP is used to analyze the effect that offshore converters have on the resonant frequency of the offshore grid and on system stability. The positive-net-damping criterion, originally proposed for subsynchronous analysis, has been adapted to determine the stability of the HVDC-connected OWPP. The reformulated criterion enables the net damping of the electrical series resonance to be evaluated and establishes a clear relationship between electrical resonances of the HVDC-connected OWPPs and stability. The criterion is theoretically justified, with analytical expressions for low-frequency series resonances being obtained and stability conditions defined based on the total damping of the OWPP. Examples are used to show the influence that HVDC converter control parameters and the OWPP configuration have on stability. A root locus analysis and time-domain simulations in PSCAD/EMTDC are presented to verify the stability conditions.
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Lectura remota de comptadors analògics

  • Caldera Sànchez, Raül
Aquest projecte té el propòsit fer possible la lectura a distància de diferents comptadors analògics, per tal de tenir un millor control i seguiment del consum energètic, ja sigui d’ una casa, d’ una empresa, etc… i per facilitar la obtenció i posterior tractament de les dades que els comptadors ofereixen. Malgrat que avui en dia existeixen els comptadors electrònics, els quals alguns ja envien les seves lectures a una base de dades remota, complint així el propòsit d’ aquest projecte, pocs ofereixen encara aquest funcionalitat, i per altra banda encara és molt freqüent l’ ús de comptadors analògics. Per això, en aquest projecte es proposa un sistema capaç de proporcionar la mateixa funcionalitat per a aquests comptadors. Per tal de realitzar això, en aquest projecte s’ ha construït un prototip del sistema, que consta d’ una càmara per a prendre imatges del comptador, una Raspberry Pi que processa les imatges preses per la càmara, n’ extreu les dades desitjades i les envia a un ordinador/servidor remot que guarda aquestes dades en una base de dades, ja preparades per al seu tractament, i també ofereix la possibilitat de poder-les passar a un format que es pugui llegir amb programes com el LibreOfficeCalc. El projecte també consta del desenvolupament d’ una montura que sosté el sistema físic (càmara, Raspberry Pi, comptador) i que conté elements per tal de maximitzar l’ eficiència del sistema (miralls per a prendre imatges dels comptadors amb angles incilinats i que permeten reduïr l’ espai que ocupa el sistema, un braç articulat per a moure la càmara, la possibilitat de incloure-hi díodes LED per a iluminar el comptador a la foscor…).
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Influential variables on the profitability of hospital companies

  • Creixans Tenas, Judit
  • Arimany-Serrat, Núria
Purpose: This study attempts to evidence the economic and financial health of Spanish hospital companies in the period 2008-2015 and discover the variables that explain their profitability for survival and the opportune performance of their assets during a period of technological revolution and austerity. Design/methodology: The study methodology consists of the short and long-term financial analysis of the companies in the study sample during the period 2008-2015, together with analysis is of their economic state, equity and treasury. To add value to the research, the profitability of the hospital companies has been explained in terms of the following independent variables: short-term solvency, debt, business size, legal form, GDP per capita, population density of and indicators of Corporate Social Responsibility. Findings: In the analyzed period, the economic and financial health of hospital companies is characterized by acceptable liquidity and indebtedness that significantly influence its profitability; this is accompanied by good financial and expenditure management, though it is necessary to improve the management of assets. Research limitations/implications: It was not possible to obtain data for 2016, as it was not available in the database used (SABI). These data would have been useful to evaluate the changes in trends that are taking place in the health sector due to the technological revolution and economic policies affecting it. Practical implications: The health sector is one of the pillars on which society is based, and therefore knowing detailed economic and financial information allows us to make appropriate decisions, both on the hospital level and in terms of the economic policies of governments. Social implications: This study provides evidence of the financially relevant indicators that healthcare companies must control for their survival and to provide proper service to society in general. The research also identifies non-financial variables that contribute to improving the profitability of hospital companies, while also having a good impact on society. Originality/value: To indicate financial and non-financial measures to improve the profitability of hospital companies at a time of technological innovation and austerity., Peer Reviewed
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