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UPCommons, el portal d'accés obert al coneixement de la UPC, està format pel conjunt de dipòsits institucionals oberts de la UPC i té com a missió garantir la preservació de la producció docent i de recerca cientificotècnica de la Universitat, maximitzant-ne la visibilitat i, conseqüentment, incrementant-ne l’impacte en la docència i la recerca de tot el món.
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Electromagnetic evaluation of an in-wheel double rotor axial-flux switched reluctance motor for electric traction

dv., 02/09/2018 - 11:37
Electromagnetic evaluation of an in-wheel double rotor axial-flux switched reluctance motor for electric traction Andrada Gascón, Pedro; Martínez Piera, Eusebio; Torrent Burgués, Marcel; Blanqué Molina, Balduino In this paper, a novel in-wheel double rotor axialflux switched reluctance motor for electric traction is presented. The proposed double rotor axial-flux switched reluctance motor has a particular disposition of the stator and rotor poles that provides short flux path without flux reversal. The ferromagnetic pieces of the stator and the rotor are built using soft magnetic composites. Electromagnetic analysis is performed using three dimensional finite element analyses, 3D FEA. Matlab-Simulink simulation coupled with the results of finite element analysis proves that the proposed motor drive is suitable for the propulsion of a given E-scooter.
Categories: Novetats

Wave storm tracking at the NW Mediterranean Sea

dv., 02/09/2018 - 11:31
Wave storm tracking at the NW Mediterranean Sea Flores Osuna, Carla Wave storms play a key role in micro-tidal environments like the NW Mediterranean Sea. However, the physics of wave generation and propagation involve uncertainty, specially because most of the measurements that we have are in local points (i.e. buoys). This shortcoming can be alleviated with spatial characterization derived from regional wave models. The aim of this TFM is to characterize the main spatial features (tracking) of a subset of recent wave storm events at the Catalan Coast. Results will serve for improving a coastal early warning system.
Categories: Novetats

MeRLiN: Exploiting dynamic instruction behavior for fast and accurate microarchitecture level reliability assessment

dv., 02/09/2018 - 11:29
MeRLiN: Exploiting dynamic instruction behavior for fast and accurate microarchitecture level reliability assessment Kaliorakis, Manolis; Gizopoulos, Dimitris; Canal Corretger, Ramon; González Colás, Antonio María Early reliability assessment of hardware structures using microarchitecture level simulators can effectively guide major error protection decisions in microprocessor design. Statistical fault injection on microarchitectural structures modeled in performance simulators is an accurate method to measure their Architectural Vulnerability Factor (AVF) but requires excessively long campaigns to obtain high statistical significance. We propose MeRLiN1, a methodology to boost microarchitecture level injection-based reliability assessment by several orders of magnitude and keep the accuracy of the assessment unaffected even for large injection campaigns with very high statistical significance. The core of MeRLiN is the grouping of faults of an initial list in equivalent classes. All faults in the same group target equivalent vulnerable intervals of program execution ending up to the same static instruction that reads the faulty entries. Faults in the same group occur in different times and entries of a structure and it is extremely likely that they all have the same effect in program execution; thus, fault injection is performed only on a few representatives from each group. We evaluate MeRLiN for different sizes of the physical register file, the store queue and the first level data cache of a contemporary microarchitecture running MiBench and SPEC CPU2006 benchmarks. For all our experiments, MeRLiN is from 2 to 3 orders of magnitude faster than an extremely high statistical significant injection campaign, reporting the same reliability measurements with negligible loss of accuracy. Finally, we theoretically analyze MeRLiN's statistical behavior to further justify its accuracy.
Categories: Novetats

Gradient based porosity calculation in casting simulation

dv., 02/09/2018 - 11:27
Gradient based porosity calculation in casting simulation Díez Rodríguez, Daniel Porosity is one of the most common defects in casting production. When some parts of the casting begin to solidify they contract due to the difference of densities between the liquid and solid phases. The areas that are still liquid feed the solidifying regions until at some point feeding is not longer possible due to the growth of the solid phase and porosity begins to form. If the feeding cut is due to the growth of dendrites, pores will have a very small size and will be usually mentioned as microporosity. When a pool of liquid is isolated, surrounded by solid material, a big void will appear known as macroporosity. If the liquid pool is connected to the exterior it will form pipe shrinkage. The aim of this work is the implementation of a microporosity model inside the commercial casting software Click2Cast, based on the general finite elements framework Kratos Multiphysics. The model that has been implemented is based on the Dimensionless Niyama method developed by Carlson and Beckermann in 2008. This approach requires the recover of the gradient of the temperature. In order to do this, several methods to compute the gradients were developed and implemented inside the code. Finally, another model to calculate macroporosity and pipe shrinkage is being currently implemented. This method is based on the calculation of the pressure during the solidification. No results are provided for this model as still further work is needed to expect a correct under different circumstaces .The objective is that after validation, this model will be also included in Click2Cast.
Categories: Novetats

Parsing logical grammar: CatLog3

dv., 02/09/2018 - 11:11
Parsing logical grammar: CatLog3 Morrill, Glyn CatLog3 is a Prolog parser/theorem-prover for (type) logical (categorial) grammar. In such logical grammar, grammar is reduced to logic: a string of words is grammatical if and only if an associated logical statement is a theorem. CalLog3 implements a logic extending displacement calculus, a sublinear fragment including as primitive connectives the continuous (Lambek) and discontinuous wrapping connectives of the displacement calculus, additives, 1st order quantifiers, normal modalities, bracket modalities and subexponentials. In this paper we survey how CatLog3 is implemented on the principles of Andreoli’s focusing and a generalisation of van Benthem’s count-invariance.
Categories: Novetats

Experimental thermal model of a high temperature fuel cell stack

dc., 02/07/2018 - 14:34
Experimental thermal model of a high temperature fuel cell stack Serri, Flavia; Serra, Maria; Costa Castelló, Ramon HT- PEM fuel cells (operating termperature >100°C), in comparison to PEM fuel cells: have better reaction kinetics; have higher CO tolerance; do not present problems with liquid water formation; and can be used as a CH&P generator. The main objective of this work is to obtain a thermal model of a HT-PEMFC based on experimental data. The model is aimed at the design of temperature controllers. Second order transfer functions have shown to achieve fittings to the experimental data greater than 87% both for closed and open heat management openings.
Categories: Novetats

Growth of sobolev norms for the cubic defocusing NLS with a convolution potential

dc., 02/07/2018 - 14:26
Growth of sobolev norms for the cubic defocusing NLS with a convolution potential Guàrdia Munarriz, Marcel Fix s > 1. Colliander et al. proved in (Invent Math 181:39–113, 2010 )the existence of solutions of the cubic defocusing nonlinear Schrödinger equation in the two torus whose s -Sobolev norm undergoes arbitrarily large growth as time evolves. In this paper we generalize their result to the cubic defocusing nonlinear Schrödinger equation with a convolution potential. Moreover, we show that the speed of growth is the same as the one obtained for the cubic defocusing nonlinear Schrödinger equation in Guardia and Kaloshin (Growth of Sobolev norms in the cubic defocusing Nonlinear Schrödinger Equation. To appear in the Journal of the European Mathematical Society, 2012 )
Categories: Novetats

Wind speed time series reconstruction using a hybrid neural genetic approach

dc., 02/07/2018 - 14:17
Wind speed time series reconstruction using a hybrid neural genetic approach Rodriguez Rangel, Hector; Flores, J; Puig Cayuela, Vicenç; Morales, L; Guerra, A; Calderon, F Currently, electric energy is used in practically all modern human activities. Most of the energy produced came from fossil fuels, making irreversible damage to the environment. Lately, there has been an effort by nations to produce energy using clean methods, such as solar and wind energy, among others. Wind energy is one of the cleanest alternatives. However, the wind speed is not constant, making the planning and operation at electric power systems a difficult activity. Knowing in advance the amount of raw material (wind speed) used for energy production allows us to estimate the energy to be generated by the power plant, helping the maintenance planning, the operational management, optimal operational cost. For these reasons, the forecast of wind speed becomes a necessary task. The forecast process involves the use of past observations from the variable to forecast (wind speed). To measure wind speed, weather stations use devices called anemometers, but due to poor maintenance, connection error, or natural wear, they may present false or missing data. In this work, a hybrid methodology is proposed, and it uses a compact genetic algorithm with an artificial neural network to reconstruct wind speed time series. The proposed methodology reconstructs the time series using a ANN defined by a Compact Genetic Algorithm.
Categories: Novetats

Modeling and control of HTPEMFC based combined heat and power for confort control

dc., 02/07/2018 - 14:11
Modeling and control of HTPEMFC based combined heat and power for confort control Martínez Molina, Pau; Serra, Maria; Costa Castelló, Ramon In this work the dynamic model of a domestic heating system is described. The heating system is based on a High Temperature PEM Fuel Cell. The model corresponds to a home placed in the city of Barcelona. The set of equations describing its behavior, the implementation in MATLAB/Simulink and some preliminary results for the control system are described. © 20xx 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
Categories: Novetats

Minas a cielo abierto: seguridad en las voladuras

dc., 02/07/2018 - 14:10
Minas a cielo abierto: seguridad en las voladuras Campoy Pizarro, Ainara El objetivo de este trabajo es realizar un análisis de los riesgos en el proceso de realización de una voladura, en minas de cielo abierto y proponer medidas de seguridad. Para ello he realizado un análisis de la voladura dividiéndola en cinco apartados, cada apartado tendrá subestructuras explicativas, en el primer apartado se contextualiza el proyecto, se hace una explicación de los tipos de minas y voladuras, centrándose en las minas de cielo abierto. Seguidamente, se explica la primera fase de una voladura, donde se encuentran los hecho previos y necesarios para poder realizar el la voladura. El tercer apartado, es durante la manipulación del explosivo, carga de barreno y el disparo de la voladura, a continuación, es el trabajo inmediatamente posterior a la voladura, los posibles barrenos fallidos, la necesidad de destruir parte del explosivo. Estos tres apartados, son el eje central del trabajo ya que a la vez de mencionar el proceso se indicarán los riesgos y las medidas preventivas a aplicar. Para finalizar en el último apartado, mostraré la conclusión del proyecto, en la que contrastando los datos del análisis realizado y datos obtenidos del ministerio de energía y turismo, podemos ver que la realización de una voladura atañe un conjunto de riesgos graves para los trabajadores y que aun siendo la manipulación de explosivo la parte central de una voladura, y siendo una tarea con riesgos elevados, los accidentes se suelen producir más en otros puntos del proceso de voladura teniendo estos consecuencias igual o más graves.
Categories: Novetats

Datos para el conocimiento del patrimonio minero de la comarca aragonesa del Somontano. I Tejeras

dc., 02/07/2018 - 14:05
Datos para el conocimiento del patrimonio minero de la comarca aragonesa del Somontano. I Tejeras Mata Perello, Josep Maria; Alfonso Abella, María Pura; Climent Costa, Ferran; Parcerisa Duocastella, David; Pocoví Juan, Andrés; Vilaltella Farràs, Jaume En este artículo, nos centraremos en el Patrimonio Minero de la comarca aragonesa del Somontano. Se trata de una comarca situada en el centro de Aragón, repartida entre la Depresión Geológica del Ebro (entre afloramientos de materiales cenozoicos) y el Sistema Pirenaico (entre afloramientos de materiales mesozoicos). Dentro de esta comarca existen interesantes elementos del Patrimonio Minero de la Comunidad Aragonesa. En este caso nos centraremos en el patrimonio minero relacionado con las tejeras.
Categories: Novetats

Influence of injection molding parameters on the morphology, mechanical and surface properties of ABS foams

dc., 02/07/2018 - 14:02
Influence of injection molding parameters on the morphology, mechanical and surface properties of ABS foams Gomez Monterde, J.; Sánchez Soto, Miguel; Maspoch Rulduà, Mª Lluïsa In this work, microcellular ABS foams were studied. A series of injection molding samples defined by a design of experiments was carried out to analyze the effect of shot volume, mold temperature, and injection velocity on the morphology, mechanical properties, and surface roughness of microcellular samples. A predominant influence of shot volume on the cell structure and tensile properties was evidenced. Higher cell densities and narrower cell size distributions were obtained at lower injection volume. However, elastic modulus and tensile strength were improved by increasing the shot size. The effect of mold temperature and injection velocity was secondary. Higher levels of mold temperature and injection rate provided finer cell morphologies, but their effects on the elastic modulus and tensile strength were negligible. The decrease in shot volume and increase in gas content led to poor surface quality, whereas it was greatly improved by raising both mold temperature and injection velocity
Categories: Novetats

Datos para el conocimiento del patrimonio minero de la comarca aragonesa del Bajo Cinca / Baix Cinca

dc., 02/07/2018 - 14:01
Datos para el conocimiento del patrimonio minero de la comarca aragonesa del Bajo Cinca / Baix Cinca Mata Perello, Josep Maria; Alfonso Abella, María Pura; Climent Costa, Ferran; Parcerisa Duocastella, David; Pocoví Juan, Andrés; Vilaltella Farràs, Jaume En este artículo, nos centraremos en el Patrimonio Minero de la comarca aragonesa del Bajo Cinca / Baix Cinca. Se trata de una comarca situada en el centro de Aragón, ubicada plenamente dentro de la Depresión Geológica del Ebro, entre afloramientos de materiales cenozoicos. Dentro de esta comarca existen interesantes elementos del Patrimonio Minero de la Comunidad Aragonesa.
Categories: Novetats

Gestión centralizada de la iluminación en Terminal 1 del aeropuerto Barcelona-El Prat

dc., 02/07/2018 - 13:59
Gestión centralizada de la iluminación en Terminal 1 del aeropuerto Barcelona-El Prat Borraz Rocafull, Óscar Este trabajo consiste en el estudio de una gestión centralizada de iluminación en la Terminal T1 del Aeropuerto de Barcelona-El Prat. Se dan a conocer los sistemas y subsistemas del control de iluminación, con base KNX-EIB (sistema estándar de interconexión de dispositivos) y su central de gestión. También se explican los fallos encontrados al finalizar la obra de construcción de la T1 (terminada en 2009) o los sucedidos durante su operatividad. Así como mejoras para su funcionamiento y uso aplicadas o bien que se podrían ejecutar en un futuro. La conclusión principal que se extrae tras el análisis de todo el seguimiento es la flexibilidad de modificación que permite la base del sistema KNX en las funcionalidades de sus componentes. Unido a un sistema central, ofrece una gran supervisión y control del alumbrado, permitiendo un gran ahorro energético. Como contrapunto, se detecta la necesidad de personal especializado con conocimientos en domótica. Además, se observa que no es necesario usar este sistema en toda la extensión del edificio por su coste elevado, siendo recomendable establecer su aplicación en las zonas comunes y oficinas.
Categories: Novetats

Datos para el conocimiento del patrimonio minero de la comarca aragonesa de los Monegros. Las Tejeras

dc., 02/07/2018 - 13:58
Datos para el conocimiento del patrimonio minero de la comarca aragonesa de los Monegros. Las Tejeras Mata Perello, Josep Maria; Alfonso Abella, María Pura; Climent Costa, Ferran; Parcerisa Duocastella, David; Pocoví Juan, Andrés; Vilaltella Farràs, Jaume En este artículo, nos centraremos en el Patrimonio Minero de la comarca aragonesa de los Monegros, especialmente en el relacionado con las Tejeras. Se trata de una comarca situada en el centro de Aragón, ubicada totalmente dentro de la Depresión Geológica del Ebro, entre afloramientos de materiales cenozoicos. Dentro de esta comarca existen interesantes elementos del Patrimonio Minero de la Comunidad Aragonesa. Estos elementos se hallan relacionados fundamentalmente con Tejeras y con Hornos de Yeso. En esta comunicación, nos centraremos especialmente en el primer grupo: en las Tejeras.
Categories: Novetats

Memòria d'activitats i recull d'actuacions clau 2017

dl., 02/05/2018 - 14:36
Memòria d'activitats i recull d'actuacions clau 2017 Escola Tècnica Superior d'Arquitectura del Vallès. Biblioteca
Categories: Novetats

Influence of gap junction dynamics on the stability of reentrant waves in cardiac tissue

dl., 02/05/2018 - 13:47
Influence of gap junction dynamics on the stability of reentrant waves in cardiac tissue Hawks, Claudia; Elorza Barbajero, Jorge; Echebarría Domínguez, Blas; Rodríguez Cantalapiedra, Inma; Peñaranda Ayllón, Angelina; Bragard, Jean Constant conductances are often assumed when model- ing cardiac tissue. However experimental evidences have shown that gap junctions (GJ) actually connect adjacent cardiac myocytes. These GJ are complex proteins of the connexin family (Cx40; Cx43; Cx45 are the most common in human). These GJ modify the conductances between cardiac cell through a dynamical process. The aim of this study is to develop a bidomain model of the cardiac tis- sue where the dynamics of the connexins is also included. In particular we will compare the differences associated with the use of a monodomain versus bidomain formula- tion in inducing intra-cellular conductance variations. We have found that the monodomain formulation gives con- ductance variations a factor four to five larger with respect to the bidomain formulation.
Categories: Novetats

Memòria: curs 2010-2011. Facultat de Matemàtiques i Estadística (FME)

dl., 02/05/2018 - 13:39
Memòria: curs 2010-2011. Facultat de Matemàtiques i Estadística (FME)
Categories: Novetats

Memòria: curs 2009-2010. Facultat de Matemàtiques i Estadística (FME)

dl., 02/05/2018 - 13:38
Memòria: curs 2009-2010. Facultat de Matemàtiques i Estadística (FME)
Categories: Novetats

Memòria: curs 2008-2009. Facultat de Matemàtiques i Estadística (FME)

dl., 02/05/2018 - 13:37
Memòria: curs 2008-2009. Facultat de Matemàtiques i Estadística (FME)
Categories: Novetats

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