Novetats

Facultad de Nautica en la nueva bocana Nord, Barcelona.

UPCommons - dj., 01/18/2018 - 12:46
Facultad de Nautica en la nueva bocana Nord, Barcelona. Rodriguez Gil, Adriana Qualificació obtinguda: 9,5 M.H.
Categories: Novetats

Time-resolved near infrared light propagation using frequency domain superposition

UPCommons - dj., 01/18/2018 - 11:57
Time-resolved near infrared light propagation using frequency domain superposition Wojtkiewicz, Stanislaw; Durduran, Turgut; Dehghani, Hamid Time-resolved temporal point spread function (TPSF) measurement of near infrared spectroscopic (NIRS) data allows the estimation of absorption and reduced scattering properties of biological tissues. Such analysis requires an iterative calculation of the theoretical TPSF curve using mathematical and computational models of the domain being imaged which are computationally complex and expensive. In this work, an efficient methodology for representing the TPSF data using a superposition of cosines calculated in frequency domain is presented. The proposed method is outlined and tested on finite element realistic models of the human neck and head. Using an adult head model containing ~140k nodes, the TPSF calculation at each node for one source is accelerated from 3.11 s to 1.29 s within an error limit of ± 5% related to the time domain calculation method.
Categories: Novetats

Compact, multi-exposure speckle contrast optical spectroscopy (SCOS) device for measuring deep tissue blood flow

UPCommons - dj., 01/18/2018 - 11:09
Compact, multi-exposure speckle contrast optical spectroscopy (SCOS) device for measuring deep tissue blood flow Dragojević, Tanja; Hollmann, Joseph L.; Tamborini, Davide; Portaluppi, Davide; Buttafava, Mauro; Culver, Joseph P.; Villa, Federica; Durduran, Turgut Speckle contrast optical spectroscopy (SCOS) measures absolute blood flow in deep tissue, by taking advantage of multi-distance (previously reported in the literature) or multi-exposure (reported here) approach. This method promises to use inexpensive detectors to obtain good signal-to-noise ratio, but it has not yet been implemented in a suitable manner for a mass production. Here we present a new, compact, low power consumption, 32 by 2 single photon avalanche diode (SPAD) array that has no readout noise, low dead time and has high sensitivity in low light conditions, such as in vivo measurements. To demonstrate the capability to measure blood flow in deep tissue, healthy volunteers were measured, showing no significant differences from the diffuse correlation spectroscopy. In the future, this array can be miniaturized to a low-cost, robust, battery operated wireless device paving the way for measuring blood flow in a wide-range of applications from sport injury recovery and training to, on-field concussion detection to wearables.
Categories: Novetats

Model calibration for leak localization, a real application

UPCommons - dj., 01/18/2018 - 10:58
Model calibration for leak localization, a real application Sanz, Gerard; Meseguer Amela, Jordi; Pérez Magrané, Ramon The localization of leaks in Water Distribution Networks has a major relevance in terms of environmental and economic efficiency. This localization is generally carried on in situ by human operators using time consuming methods like acoustic loggers. Nevertheless, the automated aid provided to the operators is continuously increasing thanks to the exhaustive use of models. Models that have to be calibrated and updated in order to provide proper help and an improvement in the leak search. This paper presents an experience of leak localization using steady state models combined with a demand calibration algorithm. The calibration produces a notable improvement of the localization accuracy and signals changes in the network configuration. Results presented are based on real data and a real leak provoked for the test.
Categories: Novetats

Leak detection in a DMA, a real application of flow modelling

UPCommons - dj., 01/18/2018 - 10:51
Leak detection in a DMA, a real application of flow modelling Jiménez, Víctor; Grau, Sergi; Pérez Magrané, Ramon This paper presents a versatile methodology to calculate parameters that characterise the demand of a DMA. This parameters are used for the leak modelling so that a predictive model is built and trained with historical data and used to detect on-line new leaks so that the repair time can be reduced applying proper leak localisation techniques. This methodology has been programmed using R where the modelling packages available provide assortment of predictive models easily to implement. It has been integrated in a Data analysis tool in order to utilise the great amount of information coming continuously from the WDN. Once the methodology and the tool are described the results applied to a real DMA are presented. This work has been carried out by the fundació CTM Centre Tecnològic (CTM) collaborating with Research Center for Supervision, Safety and Automatic Control (CS2AC) within a research project of Aigües de Manresa.
Categories: Novetats

Data setup for water distribution system supervision

UPCommons - dj., 01/18/2018 - 10:14
Data setup for water distribution system supervision Pérez Magrané, Ramon; Grau, Sergi; Jimenez, Victor; Martínez, Xavier; Tomas, Ricard The availability of on-line data coming from the water distribution systems (WDS) allows the monitoring of such critical infrastructures. Nevertheless the huge amount of data that come to the control centre implies an enormous processing challenge [4]. The use of data avoids any physical theory and relies on statistical correlations and inferences. Nevertheless the previous efforts in modelling the networks encourage the companies to fusion information coming from both sources. Models help validating data and data update these models. This paper presents the first stage of an ongoing project focused in the integration of data and models. Data are collected, harmonised and validated using the models so that they will be used in following stages of the project for the supervision of the WDS (water balance and quality). A tool is being developed in R where the different modules will be integrated.
Categories: Novetats

Adaptación y cambio de uso de la masía d'en Cabanyes a hotel

UPCommons - dj., 01/18/2018 - 09:27
Adaptación y cambio de uso de la masía d'en Cabanyes a hotel Ortigosa García, Raúl Este proyecto consiste en la adaptación y cambio de uso de una masía para convertirla en un hotel. Escogiendo como punto de partida La Masía Cabanyes, situada a las afueras de Vilanova y la Geltrú. La casa perteneció en sus orígenes a la familia Cabanyes, pasando como herencia de padres a hijos, hasta que cosas del destino, cae en abandono y es adquirida por el ayuntamiento de Vilanova i la Geltrú a principios de los años 80. Tras varias consultas en el archivo municipal del garraf, para localizar documentación, encontré una serie de planos sin escala ni medidas, con lo cual, comencé a realizar una serie de croquis para poder hacer el levantamiento de los diferentes planos. Podemos constatar que esta construcción tiene unos 200 años de antigüedad y se han realizado en ella diversas reformas, hasta llegar al estado actual. A continuación, en la presente memoria encontrarán información sobre la historia de la casa y la evolución a lo largo de los años hasta nuestros días. El edificio consta de una planta cuadrangular, compuesto de planta baja, planta principal, planta piso y cubierta central con un cuerpo en U en la planta baja que forma una galería superior con arcos de medi punto. Muros de carga de mampostería común y ladrillo. La fachada principal compuesta simétricamente con los paramentos lisos enmarcados por pilastras de ladrillo visto de tres alturas, definiendo tres paños que soportan un entablamiento y frontón triangular. El proyecto está pensado aplicando la normativa del Código Técnico de la Edificación y contemplando aspectos de la ley de accesibilidad, respetando en todo momento temas medioambientales. Esta memoria va acompañada de planos y unos anexos para complementar y dejar definidos todos estos puntos.
Categories: Novetats

Jornada de propagació del foc per façanes

UPCommons - dj., 01/18/2018 - 09:21
Jornada de propagació del foc per façanes Rodríguez Cantalapiedra, Inma; Haurie Ibarra, Laia; Giraldo Forero, María Pilar; Massagué, Sebastià; Diego Cortés, Alberto; Gonzalez Mayans, Albert; Lacasta Palacio, Ana María; Rovira Vallhonesta, Santiago; Diez García, Xavier; Vilardaga Meseguer, Montserrat La propagació del foc per façana és considerada una de les vies de desenvolupament dels incendis més ràpides en un edifici. Per això, les mesures per limitar la propagació exterior del foc són un aspecte molt important a considerar, més encara quan parlem d'edificis en alçada. Els nombrosos incendis ocorreguts durant els últims anys en països com els Emirats Àrabs Units, on es construeixen regularment edificis en alçada, o el lamentable incendi de la Torre Grenfell de Londres ocorregut el juny d'aquest any han reobert el debat sobre la capacitat de les normatives per aconseguir nivells de seguretat contra incendis òptims, que evitin que es repeteixin aquest tipus de tragèdies. En aquest context cal avaluar si alguna cosa així podria passar en el nostre entorn, i si és així, què es podria fer per evitar-ho. Aquesta jornada pretén debatre sobre els diferents aspectes relacionats amb aquest interessant tema de la mà de diferents experts.
Categories: Novetats

TÈCNIQUES DE REPRESENTACIÓ GRÀFICA

UPC OpenCourseware - dj., 01/18/2018 - 00:00
Facilitar i potenciar la capacitat d'abstracció.
Desenvolupar i exercitar la imaginació espacial.
Introduir conceptes, tècniques i metodologies pròpies de l'àrea de l'Expressió Gràfica a l'Enginyeria.
Interpretar i representar plànols.
Conèixer les tècniques de representació en el disseny d'objectes ( esbossos 2D i 3D, representacions tècniques i CAD paramètric).

De forma més concreta, les competències específiques d'aquesta assignatura són les següents:

Conèixer les formes planes i la seva construcció, relació i composició en el pla
Aplicar les superfícies en el disseny de objectes de formes simples i complexes.
Dissenyar objectes mitjançant projeccions de croquis i les seves corbes en l'espai.
Interpretació i lectura de plànols
Aprendre a esbossar en perspectiva.
Aprendre a esbossar objectes en planimetria.
Us de les tècniques de disseny d'objectes en 3D.
Interpretació d'objectes dissenyats en 3D.
Com presentar una part de la documentació tècnica del disseny d'objectes (plànols).
Com representar objectes amb més de dos components: CAD 3D , plànols i introducció a la presentació virtual i animació.
Categories: Novetats

METODOLOGIA DEL DISSENY

UPC OpenCourseware - dj., 01/18/2018 - 00:00
OAG1: adquirir una visió global de les metodologies aplicades durant les diferents etapes que integren el procés de disseny industrial.
OAG2: capacitar per resoldre problemes de disseny en les seves etapes bàsiques (preliminar, conceptual i aplicat)
OAG3: introduir algunes de les tècniques metodològiques més habituals associades al disseny industrial.
OAG4: treballar amb casos pràctics de creativitat, disseny i re-disseny industrial.
Categories: Novetats

Community sharing of spare network capacity

UPCommons - dc., 01/17/2018 - 23:24
Community sharing of spare network capacity Dimogerontakis, Emmanouil; Meseguer Pallarès, Roc; Navarro Moldes, Leandro; Ochoa, Sergio; Veiga, Luis In several community scenarios, people share benevolently their spare broadband Internet access connectivity with other people who cannot afford it. Although laudable, this sharing process can negatively affect the service received by the primary users, thus jeopardizing the continuity of this community service. In this paper we propose the use of a gateway that separates the traffic of the primary users from that of the secondary users, the beneficiaries of this sharing. We analyze the impact and behavior of several mechanisms for using this gateway, to determine how to maximize network utilization, use of the excess network capacity, and minimize the impact on the primary traffic. As a result we present a set of lessons learned and recommendations. Particularly, some strategies that use tunneling for managing the primary and secondary traffic achieve the best performance isolation for the primary user, while the secondary user obtains the spare capacity equivalent to non-differentiated best effort, with a limited penalty (around 20%). Combined with complementary queueing techniques (instead of FIFO), other important flows for the user experience (such as DNS or ICMP) can be practically unaffected.
Categories: Novetats

Client-side routing-agnostic gateway selection for heterogeneous wireless mesh networks

UPCommons - dc., 01/17/2018 - 23:18
Client-side routing-agnostic gateway selection for heterogeneous wireless mesh networks Dimogerontakis, Emmanouil; Neto, João; Meseguer Pallarès, Roc; Navarro Moldes, Leandro; Veiga, Luis Citizens develop Wireless Mesh Networks (WMN) in many areas as an alternative or their only way for local interconnection and access to the Internet. This access is often achieved through the use of several shared web proxy gateways. These network infrastructures consist of heterogeneous technologies and combine diverse routing protocols. Network-aware state-of-art proxy selection schemes for WMNs do not work in this heterogeneous environment. We developed a client-side gateway selection mechanism that optimizes the client-gateway selection, agnostic to underlying infrastructure and protocols, requiring no modification of proxies nor the underlying network. The choice is sensitive to network congestion and proxy load, without requiring a minimum number of participating nodes. Extended Vivaldi network coordinates are used to estimate client-proxy network performance. The load of each proxy is estimated passively by collecting the Time-to-First-Byte of HTTP requests, and shared across clients. Our proposal was evaluated experimentally with clients and proxies deployed in guifi.net, the largest community wireless network in the world. Our selection mechanism avoids proxies with heavy load and slow internal network paths, with overhead linear to the number of clients and proxies.
Categories: Novetats

Les vies del morrot: El moll de San Bertrán, Barcelona.

UPCommons - dt., 01/16/2018 - 13:59
Les vies del morrot: El moll de San Bertrán, Barcelona. Marti Elias, Joan Qualificació obtinguda: 9
Categories: Novetats

Continuing professional education for engineering faculty: transversal integration of Sustainable Human Development in basic engineering sciences courses

UPCommons - dt., 01/16/2018 - 13:59
Continuing professional education for engineering faculty: transversal integration of Sustainable Human Development in basic engineering sciences courses Pérez Foguet, Agustí; Lazzarini, Boris The integration of sustainable development in higher education is increasingly recognised as a priority for a growing number of universities, nonetheless, barriers for change remain and particular attention should be given to the success factors fostering an effective integration. The present contribution analyses the extent to which a professional development programme, aimed at engaging and empowering faculty, has positive effects to integrate sustainable human development principles into existing courses of engineering. Specifically, the research focuses on the effects of the integration of sustainable human development in new teaching modules in a subject of basic engineering science, implemented in regular courses of the first year of the degree in engineering. The methodology includes i) a standardised test to assess sustainability literacy of the students; ii) a focus group conducted with the students of the engineering courses involved in the initiative; and iii) an in-deep interview conducted with the academic coordinator of the subject analysed. The results of the present case study highlight the relevance of professional development programmes addressed to academics with regard to the integration of sustainability principles specifically in formal science disciplines. The conclusions highlight relevant insights from the case study that are useful for supporting further integration of sustainable development in engineering disciplines.
Categories: Novetats

Construction and application of Bayesian networks to support decision-making in the water, sanitation and hygiene sector: a case study of SIASAR initiative in Central America

UPCommons - dt., 01/16/2018 - 13:34
Construction and application of Bayesian networks to support decision-making in the water, sanitation and hygiene sector: a case study of SIASAR initiative in Central America Pérez Foguet, Agustí; Requejo Castro, David; Giné Garriga, Ricard; Martínez Crespo, Gonzalo; Rodríguez Serrano, Antonio The 2030 Agenda includes a dedicated goal on water and sanitation (SDG 6) that sets out to “ensure availability and sustainable management of water and sanitation for all”. SDG 6 expands the MDG focus on drinking water and sanitation to cover the entire water cycle. A clear lesson from the MDGs is that we cannot manage what we do not measure, and there is little doubt about the role of monitoring and evaluation data in providing the evidence base for decision-making. Against this background, a number of composite indicator frameworks have been implemented to make water and sanitation quality services available and accessible to all, particularly to those most in need. Despite their significance in sector monitoring, indicators are not completely adequate to provide an insight into the complex cause and effect relations within water, sanitation and hygiene (WaSH) issues. The flexibility of Bayesian Networks (Bns) have been exploited to integrate multiple and simultaneous cause-effect or dependence relationships and unravel the linkages between poverty and WaSH services. In consequence, Bns have proved to be effective in project planning and monitoring support. Three major weaknesses however hinder a wider use of this monitoring approach in sector planning: i) an increased data demand, ii) software availability to run the networks, and iii) lack of a systematic methodology to deal with networks generation. In this study, open-databases are exploited and free software “R” is applied. One monitoring initiative is selected as initial case study due to its increasing relevance in Latin America in monitoring the WaSH sector: the Rural Water Supply and Sanitation Information System (SIASAR). On the basis of SIASAR’s conceptual framework, a simple Bn model has been applied to reflect the main issues that determine access to WaSH services. Data from Nicaragua is processed and analysed, since the Government has already carried out and completed a national baseline. The paper discusses about i) the proposed methodology to construct the networks, and ii) the potentiality of BNs in terms of evaluation and planning. It concludes that the proposed methodology represents a contribution to facilitate the use of this tool and that Bns are able to accommodate the complexities of WaSH-related issues. Additionally, they emerge as an effective management tool to support decision-makers in formulating and making informed choices between alternative actions.
Categories: Novetats

Periodic points of a Landen transformation

UPCommons - dt., 01/16/2018 - 13:20
Periodic points of a Landen transformation Gasull Embid, Armengol; Llorens, Mireia; Mañosa Fernández, Víctor We prove the existence of 3-periodic orbits in a dynamical system associated to a Landen transformation previously studied by Boros, Chamberland and Moll, disproving a conjecture on the dynamics of this planar map introduced by the latter author. To this end we present a systematic methodology to determine and locate analytically isolated periodic points of algebraic maps. This approach can be useful to study other discrete dynamical systems with algebraic nature. Complementary results on the dynamics of the map associated with the Landen transformation are also presented. Preprint
Categories: Novetats

Analysis of the optimum gain of a high-pass l-matching network for rectennas

UPCommons - dt., 01/16/2018 - 12:14
Analysis of the optimum gain of a high-pass l-matching network for rectennas Gasulla Forner, Manuel; Jordana Barnils, José; Sánchez Robert, Francesc Josep; Berenguer Sau, Jordi Rectennas, which mainly consist of an antenna, matching network, and rectifier, are used to harvest radiofrequency energy in order to power tiny sensor nodes, e.g., the nodes of the Internet of Things. This paper demonstrates for the first time, the existence of an optimum voltage gain for high-pass L-matching networks used in rectennas by deriving an analytical expression. The optimum gain is that which leads to maximum power efficiency of the rectenna. Here, apart from the L-matching network, a Schottky single-diode rectifier was used for the rectenna, which was optimized at 868 MHz for a power range from -30 dBm to -10 dBm. As the theoretical expression depends on parameters not very well-known a priori, an accurate search of the optimum gain for each power level was performed via simulations. Experimental results show remarkable power efficiencies ranging from 16% at -30 dBm to 55% at -10 dBm, which are for almost all the tested power levels the highest published in the literature for similar designs.
Categories: Novetats

Polypropylene-based porous membranes: influence of polymer composition, extrusion draw ratio and uniaxial strain

UPCommons - dt., 01/16/2018 - 12:10
Polypropylene-based porous membranes: influence of polymer composition, extrusion draw ratio and uniaxial strain Castejon Galan, Maria Del Pilar; Habibi, Kian; Saffar, Amir; Ajji, Abdellah; Martínez Benasat, Antonio; Arencón Osuna, David Several commercial grades of homo-polymer and its blends were selected to prepare microporous membranes through melt extrusion-annealing-uniaxial stretching technique (MEAUS). Branched or very fluid polypropylene was employed to modify the polymeric composition. In some blends, micro-sized calcium carbonate was added. We analysed the influence of sample composition, extrusion draw ratio, and we performed a deep study concerning the uniaxial strain rate, using in some cases extreme strain rates and strain extents. The crystalline features were studied by Differential Scanning Calorimetry (DSC), and the morphology of porous structure was analysed through Scanning Electron Microscopy (SEM). Thermal stability and thermomechanical performance was measured by thermogravimetric analysis (TGA) and dynamic-mechanical-thermal (DTMA) study. A close relationship was found between crystalline characteristics, porous morphology and the trends registered for permeability
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Tunable substrate integrated waveguide resonators

UPCommons - dt., 01/16/2018 - 12:09
Tunable substrate integrated waveguide resonators Mira, Fermin; Mateu Mateu, Jordi; Collado Gómez, Juan Carlos This paper presents a novel approach for providing SIW tunable resonators by means of placing an additional metalized via-hole on the waveguide cavity. The via-hole contains an open-loop slot on the top metallic wall. The dimensions, position and orientation of the open-loop slot defines the tuning range. Fabrication of some designs reveal good agreement between simulation and measurements. Additionally a preliminary prototype which sets the open-loop slot orientation manually is also presented, achieving the expected continuous tuning range of at least 8%. Canvi de títol a la versió final publicada per l'editor: "Mechanical tuning of substrate integrated waveguide resonators". ©2012 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

Cooperative work and continuous assessment in an electronic systems laboratory course in a telecommunication engineering degree

UPCommons - dt., 01/16/2018 - 12:08
Cooperative work and continuous assessment in an electronic systems laboratory course in a telecommunication engineering degree Jordana Barnils, José; Sánchez Robert, Francesc Josep
Categories: Novetats

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