Novetats

Adaptation and validation of the motivated strategies for learning questionnaire-mslq-in engineering students in Colombia

UPCommons - Tue, 09/12/2017 - 13:54
Adaptation and validation of the motivated strategies for learning questionnaire-mslq-in engineering students in Colombia Ramírez Echeverry, Jhon Jairo; García Carrillo, Àgueda; Olarte Dussan, Fredy Andres With the aim of characterizing self-regulated learning of engineering students in a Colombian university, students were asked to answer a Spanish version of the Motivated Strategies for Learning Questionnaire (MSLQ); this questionnaire enables obtaining information on epistemic motivation and learning strategies of the students in the courses they are studying. The data found suggest the dimensional structure of the questionnaire did not meet the context of those students. It was decided to make a new translation of the MSLQ into Spanish and make linguistic and cultural adaptations in order to achieve a valid instrument; this work began with the International Test Commission (ITC) guidelines. As a result, a new questionnaire was attained, MSLQ- Colombia. The objective of this article is to present the method used to obtain the MSLQ-Colombia, and the study of the psychometric properties of the new questionnaire. The psychometric properties studied were the construct validity, content validity and reliability. These properties were determined by factor analysis, Cronbach’s Alpha and experts consultation. The participants of this research were 1218 engineering students and 12 university teachers. The results indicate the new questionnaire is valid and reliable, provide information to those who may use MSLQ-Colombia to comprehend the results of their investigations, and offer the international community new empirical evidences on MSLQ psychometric properties. It led to the conclusion that the MSLQ- Colombia has similar psychometric properties to the original MSLQ in English, and that the new questionnaire can be useful for the Spanish speaking international community. This article can be a valuable guide for those researchers, who desire making translations-adaptations of the MSLQ into languages-cultures different from English or Spanish, and also, to translate-adapt questionnaires of self-report besides the MSLQ.
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A methodology to discover and understand complex patterns: interpreted integrative multiview clustering (I2MC)

UPCommons - Tue, 09/12/2017 - 13:46
A methodology to discover and understand complex patterns: interpreted integrative multiview clustering (I2MC) Sevilla-Villanueva, Beatriz; Gibert, Karina; Sànchez-Marrè, Miquel The main goal of this work is to develop a methodology for finding nutritional patterns from a variety of individual characteristics which can contribute to better understand the interactions between nutrition and health, provided that the complexity of the phenomenon gives poor performance using classical approaches. An innovative methodology based on a combination of advanced clustering techniques and consistent conceptual interpretation of clusters is proposed to find more understandable patterns or clusters. The Interpreted Integrative Multiview Clustering (I2MC) combines the previously proposed Integrative Multiview Clustering (IMC) with a new interpretation methodology NCIMS. IMC uses crossing operations over the several partitions obtained with the different views. Comparison with other classical clustering techniques is provided to assess the performance of this approach. IMC helps to reduce the high dimensionality of the data based on multiview division of variables. Two innovative Cluster Interpretation methodologies are proposed to support the understanding of the clusters. These are automatic methods to detect the significant variables that describe the clusters; also, a mechanism to deal with the consistency between the interpretations inter clusters of a single partition CI-IMS, or between pairs of nested partitions NCIMS. Some formal concepts are specifically introduced to be used in the NCIMS. I2MC is used to validate the interpretability of the participant’s profiles from an intervention nutritional study. The method has advantages to deal with complex datasets including heterogeneous variables corresponding to different topics and is able to provide meaningful partitions.
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Application with data acquisition of a FESTO planar surface gantry EXCM

UPCommons - Tue, 09/12/2017 - 13:25
Application with data acquisition of a FESTO planar surface gantry EXCM Vilanova Bernal, Xavier The following document contains the Final Project Degree of Xavier Vilanova Bernal. It is based on process automation in the field of biomedicine and trying to facilitate the work of a biologist and / or doctor. The implementation of this project is to cultures microorganisms in petri dishes, which so far have been managed manually, can make a big improvement in many aspects for laboratories and hospitals. For this purpose, it has been designed, developed and manufactured a prototype containing a 3-axis robot, an adapted clamp and an OpenSource controller with connectivity to a communication platform with Smartphones. Throughout the entire document has everything you need to understand and reproduce this prototype; El següent document conté el Projecte de Final de Grau (PFG) de Xavier Vilanova Bernal. Es basa en l'automatització de processos en l'àmbit de la biomedicina i que intenta facilitar les tasques d'un biòleg i / o mèdic. L'aplicació d'aquest projecte és als cultius de microorganismes en les plaques de Petri, que fins al moment s'han gestionat de manera manual, pot suposar una gran millora en molts aspectes per a laboratoris i hospitals. Per a aquesta finalitat, s'ha dissenyat, desenvolupat i fabricat un prototip que conté un robot de 3 eixos, una pinça adaptada i una controladora OpenSource amb connectivitat a una plataforma de comunicació amb Smartphones. Al llarg de tot el document es trobarà tot el necessari per entendre i reproduir aquest prototip; El siguiente documento contiene el Proyecto de Final de Grado (PFG) de Xavier Vilanova Bernal. Se basa en la automatización de procesos en el ámbito de la biomedicina y que intenta facilitar las labores de un biólogo y/o médico. La aplicación de este proyecto es a los cultivos de microorganismos en las placas de Petri, que hasta el momento se han gestionado de manera manual, puede suponer una gran mejora en muchos aspectos para laboratorios y hospitales. Para esta finalidad, se ha diseñado, desarrollado y fabricado un prototipo que contiene un robot de 3 ejes, una pinza adaptada y una controladora OpenSource con conectividad a una plataforma de comunicación con Smartphones. A lo largo de todo el documento se encontrará todo lo necesario para entender y reproducir este prototipo
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Les observacions i mesures de Pietro Mengoli (1627-1686) a la meridiana de Sant Petronio

UPCommons - Tue, 09/12/2017 - 13:08
Les observacions i mesures de Pietro Mengoli (1627-1686) a la meridiana de Sant Petronio Massa Esteve, Maria Rosa Durant els segles XVII i XVIII van ser traçades diverses línies meridianes a l’interior de les catedrals europees de Florència, Bolonya, Roma i Paris que van servir per determinar la longitud de l’any solar a través de mesures precises i contínues de la posició del Sol. En trobem referències directes del segle XVII en els treballs de Pietro Mengoli (1627-1686) i Giovanni D. Cassini (1625-1712). Mengoli, deixeble de Cavalieri, seguidor de Viète, després de publicar obres de matemàtica pura molt originals, va passar uns anys, de 1660 a 1670, sense publicar res i retirat a la seva església de Santa Mª Magdalena. És en aquesta època que col·laborà en astronomia fent observacions a la meridiana de Sant Petronio de Bolonya. El propòsit d’aquest text és reflexionar sobre el significat de les mesures i observacions fetes per Mengoli que es troben explicades a la seva obra: Refrattioni e ParallasseSolare (Bolonya, 1670). Aquesta obra és una de les primeres referències textuals d’ús de les línies meridianes com instruments de mesura astronòmiques del segle XVII. Analitzarem el contingut del text i de les cartes de Cassini que critiquen els principis i les conclusions que se’n deriven del llibre de Mengoli.
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Development of a multimaterial additive manufacturing process for electronic devices

UPCommons - Tue, 09/12/2017 - 12:46
Development of a multimaterial additive manufacturing process for electronic devices Muguruza Blanco, Asier; Bonada Bo, Jordi; Gómez Fernández, Agustín; Minguella Canela, Joaquim; fernandes, joana; Ramos, Francisco; Xuriguera Martin, Elena; Varea Espelt, Aida; Cirera Hernandez, Albert In order to increase the versatility of additive manufacturing multimaterial processes, a hybrid system has been developed, which is capable of combin ing 3D printing technology by DLP (Digital Light Processing) with a two - dimensional Drop - on - Demand Inkjet printing system. Through DLP technology based on digital micromirror devices (DMDs) it is possible to build up 3D geometries layer - by - layer using polyme rization of photo sensitive resins. Concurrently, while the construction process is performed, the I nk J et printing system is used to deposit tiny drops of conductive inks on the substrate generated, which will thus constitute an electric circuit embedded within the three dimensional structure. On the other hand, photo sensitive resins have been filled with Low Te mperature Co - f iring Ceramic (LT CC) particles , in order to modify the basis properties of the part by using sinterizable slurries. Finally the challenges in the sintering process for achieving functional parts are discussed and a few prototypes have been built in order t o validate this technology
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Instalación y puesta en marcha de un Programmable Automation Controller (PAC) y un sistema de supervisión en el laboratorio de Control Industrial

UPCommons - Tue, 09/12/2017 - 12:40
Instalación y puesta en marcha de un Programmable Automation Controller (PAC) y un sistema de supervisión en el laboratorio de Control Industrial López Fernández, Antoni
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Influence of exposure time on mechanical properties and photocuring conversion ratios for photosensitive materials used in additive manufacturing

UPCommons - Tue, 09/12/2017 - 12:18
Influence of exposure time on mechanical properties and photocuring conversion ratios for photosensitive materials used in additive manufacturing Bonada Bo, Jordi; Muguruza Blanco, Asier; Fernández Francos, Xavier; Ramis Juan, Xavier The influence of UV post - curing process on mechanical properties as well as photocuring conversion ratios is presented. An analytical model to determinate the conversion ratio for frontal polymerization is used t o define 3D printing parameters in order to obtain a conversion profile as homogeno us as possible. The mechanical properties of 3D p rinted coupons with and without UV post - curing process were obtained through experimental tensile and bending tests. Furthermore, the experimental conversion ratios of printed samples were obtained by means of FTIR spectrometry analysis. It was observed that conversion ratios and some mechanical properties increase because of UV post - curing treatment, enabling the chance to optimize the whole manufacturing process in function of the 3D printed part requiremen ts.
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To distribute or not to distribute: The question of load balancing for performance or energy

UPCommons - Tue, 09/12/2017 - 11:52
To distribute or not to distribute: The question of load balancing for performance or energy Stafford, Esteban; Pérez, Borja; Bosque, Jose L.; Beivide Palacio, Ramon; Valero Cortés, Mateo Heterogeneous systems are nowadays a common choice in the path to Exascale. Through the use of accelerators they offer outstanding energy efficiency. The programming of these devices employs the host-device model, which is suboptimal as CPU remains idle during kernel executions, but still consumes energy. Making the CPU contribute computin effort might improve the performance and energy consumption of the system. This paper analyses the advantages of this approach and sets the limits of when its beneficial. The claims are supported by a set of models that determine how to share a single data-parallel task between the CPU and the accelerator for optimum performance, energy consumption or efficiency. Interestingly, the models show that optimising performance does not always mean optimum energy or efficiency as well. The paper experimentally validates the models, which represent an invaluable tool for programmers when faced with the dilemma of whether to distribute their workload in these systems.
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DIMP: A low-cost diversity metric based on circuit path analysis

UPCommons - Tue, 09/12/2017 - 11:29
DIMP: A low-cost diversity metric based on circuit path analysis Alcaide, Sergi; Hernandez, Carles; Roca Rosell, Antoni Maria Claret; Abella, Jaume Diversity has been regarded as a desirable property of redundant instances, since it allows circuits to behave differently in front of a given fault. However, while qualitatively diversity is a well-understood concept, usable efficient metrics do not exist to quantify diversity in the context of safety-related systems. In this paper we cover this gap by proposing DIMP, a low-cost diversity metric based on analyzing the paths of the redundant circuits. We relate it to the particular case of automotive microcontrollers implementing lockstep cores and show that it can be successfully used providing relevant information for addressing common cause faults.
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Event-based control for sit-to-stand transition using a wearable exoskeleton

UPCommons - Tue, 09/12/2017 - 11:22
Event-based control for sit-to-stand transition using a wearable exoskeleton Rajasekaran, Vijaykumar; Vinagre Ruiz, Manuel; Aranda López, Juan Sit-to-stand transition is an essential step in a lower limb rehabilitation therapy, mainly for assisting the patient to transit from wheel chair to the next level of therapy. A mixed stiffness-damping control adaptation is proposed for this task which will help in reaching the final position with a constant velocity. A combination of control model is proposed to ensure the initiation and the final stage of the transition, such as to ensure stability and to maintain the equilibrium. The combined control model helps in reaching the goal position with equal participation from the user. For patient studies, such as with paraplegic patients, a combinational control model with muscle stimulation can be included to provide a complete assistance. The role of muscle stimulation and joint movement assistance is also considered in this control model. Further, final stage of this transition must ensure keeping or helping the user to maintain the upright position.
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Damage investigation of a tunnel subjected to an unplanned surface load through non-linear analysis

UPCommons - Fri, 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.
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Study of the efflux velocity induced by two propellers

UPCommons - Fri, 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.
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Estimation of synaptic conductances in presence of nonlinear effects caused by subthreshold ionic currents

UPCommons - Fri, 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.
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Plan Piloto de Lima (1949): significado histórico

UPCommons - Fri, 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.
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Does the energy label (EL) matter in the residential market?: a stated preference analysis in Barcelona

UPCommons - Fri, 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
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Estudio de la placa STM32F4 Discovery orientado a periféricos para un robot autónomo

UPCommons - Fri, 09/08/2017 - 14:15
Estudio de la placa STM32F4 Discovery orientado a periféricos para un robot autónomo Fernández Sánchez, Jordi
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Measurement of the environmental broadband electromagnetic waves in a mid-size European city

UPCommons - Fri, 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.
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Estudio de algoritmos de control de trayectoria de un vehículo virtual

UPCommons - Fri, 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

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

UPCommons - Fri, 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.
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