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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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Damage investigation of a tunnel subjected to an unplanned surface load through non-linear analysis

dv., 09/08/2017 - 17:26
Damage investigation of a tunnel subjected to an unplanned surface load through non-linear analysis Arnau Lloveras, Oriol; Molins i Borrell, Climent; Marí Bernat, Antonio Ricardo A description of the deformations and damage that occurred in a segmental tunnel lining as a consequence of an unplanned surface load is presented, as well as the numerical analyses performed for its safety assessment. The tunnel in study is located in soft soil conditions and presents a low overburden. Few months after tunnel drilling, a new bridge was constructed at surface level, placing an access embankment over the tunnel path. Monitoring points were installed along the affected section which recorded the deformation of the tunnel caused by the embankment weight. More worryingly, despite no additional loads were introduced, the deformation of the lining continued increasing significantly along the next months, indicating the existence of soil consolidation phenomena. As a consequence, structural cracks emerged along the affected section. Non-linear finite element models that realistically simulate the behaviour of the non-linear segment joints and the concrete cracking were used to characterize the actual response and strength of the lining. The results showed that most significant damages should occur at the non-visible extrados side, and characterized how they evolve along the soil consolidation process. Finally, the adopted tunnel strengthening procedure is described. First published by the International Association for Bridge and Structural Engineering (IABSE), Zurich, Switzerland, www.iabse.org; in Structural Engineering International 2017, Vol.27, issue 3, pg. 422-428.
Categories: Novetats

Study of the efflux velocity induced by two propellers

dv., 09/08/2017 - 17:08
Study of the efflux velocity induced by two propellers Mujal Colilles, Anna; Gironella Cobos, Xavier; Jaquet, A.; Gómez Gesteira, Moncho; Sánchez-Arcilla Conejo, Agustín Present analysis is related with seabed erosion caused during docking and undocking maneuvering. Twin propellers without rudder were studied using a physical model with a fixed clearance distance and three different rotating velocities. Experimental results were compared to theoretical expressions of the efflux velocity, axial velocity and finally maximum bed velocity. Efflux velocity equations overestimate the experimental results, whereas axial velocity computed using the Dutch method fits reasonably well the experimental data. However, when maximum bed velocity expressions are compared to experimental results, German method behaves better with an over estimation if a quadratic superposition of the single jets is used.
Categories: Novetats

Estimation of synaptic conductances in presence of nonlinear effects caused by subthreshold ionic currents

dv., 09/08/2017 - 14:30
Estimation of synaptic conductances in presence of nonlinear effects caused by subthreshold ionic currents Vich Llompart, Catalina; Guillamon Grabolosa, Antoni; Ditlevsen, Susanne; Berg, Rune W. Subthreshold fluctuations in neuronal membrane potential traces contain nonlinear components, and employing nonlinear models might improve the statistical inference. We propose a new strategy to estimate synaptic conductances, which has been tested using in silico data and applied to in vivo recordings. The model is constructed to capture the nonlinearities caused by subthreshold activated currents, and the estimation procedure can discern between excitatory and inhibitory conductances using only one membrane potential trace. More precisely, we perform second order approximations of biophysical models to capture the subthreshold nonlinearities, resulting in quadratic integrate-and-fire models, and apply approximate maximum likelihood estimation where we only suppose that conductances are stationary in a 50–100 ms time window. The results show an improvement compared to existent procedures for the models tested here.
Categories: Novetats

Plan Piloto de Lima (1949): significado histórico

dv., 09/08/2017 - 14:23
Plan Piloto de Lima (1949): significado histórico Ortiz Agama, Robinson Constantino El Plan Piloto de Lima (PPL), 1949, es el primer plan realizado bajo los preceptos de la Carta de Atenas que se oficializa y ejecuta en el mundo (1949). Desde que “Corbu” plantea su Plan Voisin (1925) y publica la Carta de Atenas (1942) muchos intentaron llevar a la práctica la nueva forma de planificar ciudades. Este mérito recayó en la ONPU, Lima, creada por gestión del Diputado Belaúnde (1946) cuyo primer encargo fue elaborar el Plan Regulador de Lima (PRL), del cual el PPL –su primera etapa- proponía el modelo de ciudad. El PPL, dirigido por Dorich y asesorado por Sert, Wiener y Rogers, propone los límites del crecimiento, articulado por una trama vial perimétrica y otra interna. El centro se propone cual Plan Voisin “marinado”, tabula rasa incluida. Sus grandes omisiones fueron el mar, el río y los inmigrantes. El PPL es hito de la urbanística moderna internacional.; The Pilot Plan of Lima (PPL), 1949, is the first comprehensive plan made under the provisions of the Charter of Athens became official and runs in the world. Since Le Corbusier raises his Plan Voisin and publishes the Athens Charter (1942) were many attempts to implement the new way of planning cities. This merit went to the ONPU, institution created by Arch. and Deputy Fernando Belaúnde (1946) who first assignment was the development of the Regulatory Plan of Lima, which the PPL was the first stage and proposing the city model. This plan, directed by Dorich and advised by Sert, Wiener and Rogers, Proposes the limits of growth, articulated by a perimetric road and an inner frame. The city is proposed as kind of Plan Voisin "marinated”, including tabula rasa. Its big omissions were the sea, river and migrants. The PPL is a landmark of international modern planning.
Categories: Novetats

Does the energy label (EL) matter in the residential market?: a stated preference analysis in Barcelona

dv., 09/08/2017 - 14:15
Does the energy label (EL) matter in the residential market?: a stated preference analysis in Barcelona Marmolejo Duarte, Carlos Ramiro; Bravi, M. Energy performance in buildings has become a milestone in EU environmental policy in the last 15 years. Nonetheless, in some countries such as Spain the full acceptance of the Energy Performance of Buildings Directive is still relatively rare and novel, with little evidence as to how relevant it is in the real estate market. There are different reasons for this phenomenon: on the one hand, the real estate crisis has paralyzed the completion of most of the works in new/refurbished efficient buildings (which renders it impossible to use revealed preference methods); on the other hand, information is not complete and the consumer's perception of the relevant cost/benefits could be incorrect. For this reason, assessing the trade-off between the energy label and other specific attributes of the housing market has become important. To that end, a choice experiment following an RPL (Random Parameter Logit) model was employed. This form is suitable to accommodate various empirical situations where the assumptions of the Conditional Logit model have to be relaxed. Results suggest that the Energy Label (EL) does matter in the real estate market in relation to other residential attributes. Marginal willingness to pay for an
Categories: Novetats

Estudio de la placa STM32F4 Discovery orientado a periféricos para un robot autónomo

dv., 09/08/2017 - 14:15
Estudio de la placa STM32F4 Discovery orientado a periféricos para un robot autónomo Fernández Sánchez, Jordi
Categories: Novetats

Measurement of the environmental broadband electromagnetic waves in a mid-size European city

dv., 09/08/2017 - 14:08
Measurement of the environmental broadband electromagnetic waves in a mid-size European city Fernández García, Raúl; Gil Galí, Ignacio In this paper, the level of exposure to broadband radiofrequency electromagnetic field in a mid-size European city was evaluated in accordance with the International Commission on Non-ionizing Radiation Protection guidelines from 1998. With the aim to analyse all the potential electromagnetic waves present in the city up to 18 GHz, a total of 271 locations distributed along Terrassa (Spain) have been measured. To show the results in an easy-to-interpret way by the citizen, the results have been represented in a set of raster maps. The measurement results obtained showed that the electromagnetic wave measured in all broadband frequency range along the city is much lower than the safety level according to the international regulations for both public and occupational sectors.
Categories: Novetats

Estudio de algoritmos de control de trayectoria de un vehículo virtual

dv., 09/08/2017 - 13:56
Estudio de algoritmos de control de trayectoria de un vehículo virtual Pérez Padial, Pau
Categories: Novetats

A methodology for energy prediction and optimization of a system based on the Energy Hub Concept using Particle Swarms

dv., 09/08/2017 - 13:48
A methodology for energy prediction and optimization of a system based on the Energy Hub Concept using Particle Swarms Kampouropoulos, Konstantinos; Andrade, Fabio; Cárdenas Araújo, Juan José; Romeral Martínez, José Luis In this paper, a methodology for the energy prediction for the different consumptions of a system based in the Energy Hub concept is presented. The methodology that has been used for the energy prediction is based on an Adaptive Neuro-Fuzzy Inference System. An optimization method based on Particle Swarms has been used to minimize the energy cost of a system with multiple sources such as, photovoltaic, electrical grid and natural gas.
Categories: Novetats

Marcas territoriales de la actividad industrial en el Área Metropolitana del Gran Resistencia: consideraciones para la planificación urbana en torno a su patrimonio industrial

dv., 09/08/2017 - 13:46
Marcas territoriales de la actividad industrial en el Área Metropolitana del Gran Resistencia: consideraciones para la planificación urbana en torno a su patrimonio industrial Mariño, María Patricia; Fernández Crudeli, Belén Originada por la actividad industrial, principalmente taninera, el Área Metropolitana del Gran Resistencia (AMGR) está fuertemente marcada por su infraestructura desplegada para concretar sus fines, a la vez de definir su valor patrimonial. Los poblados tanineros constituyen un claro ejemplo de una política económica liberal, con la inserción de nuevos programas urbanos y tipologías poco usuales. Actualmente, están rodeados de zonas urbanizadas con diversas tipos de funciones, que ignoran consideraciones a su valor arquitectónico y urbano. Se busca exponer la necesidad de integrar la problemática de la conservación del patrimonio industrial del AMGR en la planificación urbana, desde su reconocimiento como emergente de la reunión de diversos factores, que constituyen la planificación territorial. Se considera que a través de una gestión que incluya una visión integral del patrimonio industrial se produciría una revalorización de las marcas territoriales configurando nuevas alternativas a la planificación territorial del AMGR.; The Metropolitan Area of the Great Resistance (AMGR), originated by industrial activity, mainly tannin, is strongly marked by its infrastructure deployed to achieve its goals, while defining its patrimonial value. The tanineros settlements constitute a clear example of a liberal economic policy, with the insertion of new urban programs and unusual typologies. Currently, they are surrounded by urbanized zones with different types of functions, which ignore considerations to its architectural and urban value. It seeks to expose the need to integrate the problems of conservation of the industrial heritage of the AMGR in urban planning, from its recognition as an emergent of the meeting of various factors, which constitute territorial planning. It is considered that through a management that includes a comprehensive view of the industrial heritage would bring about a revaluation of territorial brands by configuring new alternatives to the territorial planning of the AMGR.
Categories: Novetats

Balanç energètic d'equips consumidors. Mesura i càlcul. 6: Calderes d'aigua calenta i fluids tèrmics

dv., 09/08/2017 - 13:43
Balanç energètic d'equips consumidors. Mesura i càlcul. 6: Calderes d'aigua calenta i fluids tèrmics García-Almiñana, Daniel; Cabeza Fabra, Luisa Fernanda Sisè mòdul de la col·lecció "Balanç energètic d'equips consumidors. Mesura i càlcul" que pretén oferir material de formació per a realitzar mesures de camp amb instruments portàtils i conèixer el balanç energètic dels sistemes en estudi, així com proporcionar criteris en la interpretació dels valors obtinguts en les mesures amb aquests instruments. Aquest mòdul pren com a sistema d'estudi la caldera d'aigua calenta. El balanç energètic calcula el rendiment de la caldera contrastant la calor que guanya el fluid que s'escalfa en ella amb la calor que aporta el combustible emprat en aquest procés.
Categories: Novetats

Inter-ocular asymmetry in choroidal thickness and retinal sensitivity in high myopia

dv., 09/08/2017 - 13:39
Inter-ocular asymmetry in choroidal thickness and retinal sensitivity in high myopia Alzaben, Zeyad; Cardona Torradeflot, Genís; Zapata Victori, Miguel Ángel; Zaben, Ahmad PURPOSE:: To investigate the normal range of interocular asymmetry in choroidal thickness and retinal sensitivity in high myopia without ocular fundus manifestations and to determine the relationship between interocular asymmetry and refractive error. METHODS:: Forty-three patients (35.07 ± 13.31 years) with high myopia and 45 healthy participants (39.9 ± 14.1 years) were administered an ocular coherence tomography and a microperimetry examination to determine choroidal thickness and retinal sensitivity at the foveal region and at 1, 2, and 3 mm, nasally, temporally, superiorly, and inferiorly. Absolute interocular differences were calculated to determine the normal range of asymmetry, in 95% confidence intervals. RESULTS:: The choroid was thinner in the myopic group at all explored locations (all P < 0.05), with larger absolute interocular differences in most of the choroidal locations under evaluation (all P < 0.05). Similarly, retinal sensitivity was reduced in the myopic group, although statistically significant differences were only encountered at the subfoveal location (P = 0.001). Retinal sensitivity asymmetry was found to increase with refractive error. CONCLUSION:: The expanded range of choroidal thickness and retinal sensitivity asymmetry found in high myopia in the absence of disease is of relevance when exploring these patients for early signs of ocular pathology.
Categories: Novetats

O processo de industrialização na década de 1960 e as transformações da paisagem urbana no bairro da Prata, em Campina Grande

dv., 09/08/2017 - 13:29
O processo de industrialização na década de 1960 e as transformações da paisagem urbana no bairro da Prata, em Campina Grande Alfonso de Albuquerque e Melo, Alcilia Esse texto possui como objeto de estudo, o papel da industrialização no desenvolvimento urbano do bairro da Prata, na cidade de Campina Grande- agreste do estado da Paraíba, nordeste brasileiro- durante a década de 1960. A investigação vem sendo desenvolvida pelo grupo de pesquisa Arquitetura e Lugar, do programa de pós graduação em história da UFCG/ Universidade Federal de Campina Grande, integrada com o curso de arquitetura e urbanismo da mesma instituição, e está inserida na linha voltada para história e cidade, trabalhando com a construção da história urbana campinense, relacionando conceitos de cidade, patrimônio industrial e modernidade. O objetivo é analisar a importância da industrialização no crescimento da cidade durante esse recorte temporal, observando as relações entre os diversos atores urbanos na construção de um cenário de modernidade. Como metodologia optou-se por trabalhar com uma linha de pesquisa arquitetônica e urbanística proposta por Serra (2006) que propõe o diálogo entre processo e sistemas.; This paper aims to study the role of industrialization in the urban development of the district of Prata, in the city of Campina Grande- “agreste” in the state of Paraíba, Northeastern Brazil, during the 1960s. Research has been carried out by the research group Architecture and Place, UFCG / Universidade Federal de Campina Grande, integrated with the course of architecture and urbanism of the same institution, and is inserted in the line directed to history and city, working with the construction of the urban history, relating concepts of City, industrial patrimony and modernity. The objective is to analyze the importance of industrialization in the growth of the city during this temporal cut, observing the relations between the different urban actors in the construction of a scenario of modernity. As a methodology, it was decided to work with a line of architectural and urban research proposed by Serra (2006), who proposes the dialogue between process and systems.
Categories: Novetats

Structural assessment of the Roman wall and vaults of the cloister of Tarragona Cathedral

dv., 09/08/2017 - 13:22
Structural assessment of the Roman wall and vaults of the cloister of Tarragona Cathedral Núñez Andrés, María Amparo; Buill Pozuelo, Felipe; Costa, Agustí; Puche, Josep Maria The Mediterranean city of Tarragona was a capital city in Roman times. Nowadays, the remains of the ancient constructions coexist with many subsequent buildings. This is the case of the Gothic Cathedral cloister, whose walls partially take advantage of the remains of the temenos's wall. This paper focuses on the assessment of that unique overlapping of construction phases. The investigation is performed through an unprecedented topographical survey by means of massive data capture techniques. This information is the basis for the mechanical assessment of the equilibrium conditions of the northern corner of the gallery, which is performed on the well-known theoretical framework of limit analysis by means of thrust lines. The study allowed to enhance the understanding about the equilibrium conditions and the deformation processes of the gallery masonry elements, where the mechanical relation between the Roman and Gothic walls is essential
Categories: Novetats

Balanç energètic d'equips consumidors. Mesura i càlcul. 5: Escomesa elèctrica

dv., 09/08/2017 - 13:05
Balanç energètic d'equips consumidors. Mesura i càlcul. 5: Escomesa elèctrica García-Almiñana, Daniel; Cabeza Fabra, Luisa Fernanda Cinquè mòdul de la col·lecció "Balanç energètic d'equips consumidors" que pretén oferir material de formació per a realitzar mesures de camp amb instruments portàtils i conèixer el balanç energètic dels sistemes en estudi, així com proporcionar criteris en la interpretació dels valors obtinguts en les mesures amb aquests instruments. Aquest mòdul proporciona una metodologia de càlcul i balanç energètic en escomesa elèctrica.
Categories: Novetats

Disseny d'un sistema de detecció de marcadors amb ROS i visió per computador

dv., 09/08/2017 - 12:52
Disseny d'un sistema de detecció de marcadors amb ROS i visió per computador Martínez Céspedes, Cristian
Categories: Novetats

Balanç energètic d'equips consumidors. Mesura i càlcul. 4: Bescanviadors de calor

dv., 09/08/2017 - 12:26
Balanç energètic d'equips consumidors. Mesura i càlcul. 4: Bescanviadors de calor García-Almiñana, Daniel; Cabeza Fabra, Luisa Fernanda Quart mòdul de la col·lecció "Balanç energètic d'equips consumidors" que pretén oferir material de formació per a realitzar mesures de camp amb instruments portàtils i conèixer el balanç energètic dels sistemes en estudi, així com proporcionar criteris en la interpretació dels valors obtinguts en les mesures amb aquests instruments. Aquest mòdul proporciona una metodologia de càlcul i balanç energètic en bescanviadors de calor.
Categories: Novetats

An energy prediction method using adaptive Neuro-Fuzzy Inference System and Genetic Algorithms

dv., 09/08/2017 - 12:21
An energy prediction method using adaptive Neuro-Fuzzy Inference System and Genetic Algorithms Kampouropoulos, Konstantinos; Cárdenas Araújo, Juan José; Giacometto Torres, Francisco; Romeral Martínez, José Luis This document presents an energy forecast methodology using Adaptive Neuro-Fuzzy Inference System (ANFIS) and Genetic Algorithms (GA). The GA has been used for the selection of the training inputs of the ANFIS in order to minimize the training result error. The presented algorithm has been installed and it is being operating in an automotive manufacturing plant. It periodically communicates with the plant to obtain new information and update the database in order to improve its training results. Finally the obtained results of the algorithm are used in order to provide a short-term load forecasting for the different modeled consumption processes.
Categories: Novetats

Improving the design of virtual reality devices applying an ergonomics guideline

dc., 09/06/2017 - 13:38
Improving the design of virtual reality devices applying an ergonomics guideline Mariani Susanne, Catalina; Ponsa Asensio, Pere A methodology with the objective of evaluating the aesthetics and ergonomics of virtual reality glasses is presented. Many developers apply best practices taking into account hardware features, physiological considerations and interactive patterns that provide a safe and comfortable user experience. Usually, the user tests a virtual reality application in laboratory conditions. In this work, authors are paying attention to the first time that a user tries virtual reality glasses. In this initial phase, it is necessary to analyse the first impression considering the comfort of glasses on the face and head of the user. Using ergonomics principles, this work shows the creation of heuristics inside a guideline with the aim of improving the design of low-cost virtual reality glasses.
Categories: Novetats

Minimizing the ergonomic risk and its dispersion in a mixed model assembly line using GRASP

dc., 09/06/2017 - 13:38
Minimizing the ergonomic risk and its dispersion in a mixed model assembly line using GRASP Bautista Valhondo, Joaquín; Alfaro Pozo, Rocío This work addresses a balancing problem approach whose objective is to minimizing the ergonomic risk dispersion between the set of workstations of a mixed-model assembly line and the risk level of the workstation with the greatest hazard. A GRASP procedure is proposed to achieve these two challenges simultaneously. This new procedure is compared with two Mixed Integer Linear Programs, the MILP-1 that minimizes the maximum ergonomic risk of the assembly line, and the MILP-2 that minimizes the average deviation from ergonomic risks of the set of workstations of the line. The results from the case study linked with the automotive sector indicate that the proposed GRASP is a very competitive and promising tool for further researches.
Categories: Novetats

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