Novetats

Bioinformática

UPCommons - dj., 12/07/2017 - 10:44
Bioinformática Barceló García, Miquel
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El ordenador que desaparece

UPCommons - dj., 12/07/2017 - 10:36
El ordenador que desaparece Barceló García, Miquel
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Ordenadores de ADN

UPCommons - dj., 12/07/2017 - 10:27
Ordenadores de ADN Barceló García, Miquel
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Structural analysis and damage assessment of the Vistabella Church’s Tower to establish the masonry’s active reinforcement for its restoration

UPCommons - dj., 12/07/2017 - 10:20
Structural analysis and damage assessment of the Vistabella Church’s Tower to establish the masonry’s active reinforcement for its restoration Señís López, Roger; Pavón García, Susana This paper presents the reinforcement system for the restoration of the Vistabella Church’s Tower (La Secuita, Tarragona). The intervention was carried out due to evident chronic pathologies that affected the resistant behaviour and stability of the steeple. After some numerical approaches (structural analysis and damage assessment) it became clear that, in relation the wind action, the lightness of such a masonry construction along with the feebleness of the connections between the structural members were at the basis of the problem. In order to provide additional vertical load without substantively modifying the structural scheme, a solution based on external prestressed bars, was implemented. The procedure, the theory that supports it and the results of the follow-up are described in detail, these being the objective of the paper.
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COST TU1406: an overview of European standardization on quality control of road bridges

UPCommons - dt., 12/05/2017 - 20:16
COST TU1406: an overview of European standardization on quality control of road bridges Matos, Jose C.; Casas Rius, Joan Ramon Road asset management is a task of great responsibility, since it involves vital assets to the community. An efficient transportation network is essential for the modern society from the economic, societal and environmental point of view. Today, it is a challenge for operators to manage road infrastructures under their responsibility in an efficient way, meeting the present and future needs of the community they serve. For this purpose, authorities need to produce an asset management plan which should not only define the goals to be achieved by exploiting the roadway bridge network, but that should also identify the investment needs and priorities based on a life cycle cost criteria. In addition, a proper condition assessment of these assets must be conducted to support the decision-making process regarding their preservation.
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Performance assessment of embedded distributed optical fiber sensors in reinforced concrete structures

UPCommons - dt., 12/05/2017 - 20:10
Performance assessment of embedded distributed optical fiber sensors in reinforced concrete structures Barrias, Antonio Jose de Sousa; Casas Rius, Joan Ramon; Villalba Herrero, Sergi In this paper, an experiment where distributed optical fiber sensors (DOFS) were implemented in two small concrete beams subjected to a three-point load test is outlined. Here, an optical backscatter reflectometry based DOFS is implemented simultaneously embedded in the concrete (glued to the steel rebar) and attached to the outer surface of the concrete after its hardening. For comparison purposes, three electrical strain gauges are also used in the rebar. The main objectives with this experiment, is to analyze the feasibility of installation of DOFS directly on the rebar element of a reinforced concrete beam and compare the measured strain at rebar and surface of the concrete.
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A new model to analyze corrugated steel web bridges

UPCommons - dt., 12/05/2017 - 19:15
A new model to analyze corrugated steel web bridges Lei, Jun; Xu, Dong; Turmo Coderque, José The wide application of corrugated steel web bridges has led to a rising demand on accurate tools to analyze this type of structures. Current computational models for these analyses are mainly related to those models using 2D (or 3D) beam elements, solid (shell) elements. Despite the modelling simplicity, beam models can predict the overall structural behavior but failed to provide a refined response on local areas. On the other hand, the elaborated models are better at capturing the local response. However, they are faced with computation and convergence difficulties. To fill this gap, this paper investigates a new model to analyze the structural behavior of corrugated steel web bridges. In this model, the concrete slabs and corrugated steel webs are simulated by the grid composed of 3D beam elements. Specially, the folding effects of the webs are simulated by modifying the mechanical parameters of the longitudinal elements in the grids of beams. The performance of the model is studied by comparing the results from it and those from solid models. These comparisons include the vertical deflections in the longitudinal direction and the vertical deflections in the transverse direction at midspan and one-fourth point of the span. In addition, the normal stresses and the shear stresses due to different loadings are investigated. The results indicate the accuracy and the applicability of this new model to analyze the corrugated steel web bridge.
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Condition assessment using structural system identification

UPCommons - dt., 12/05/2017 - 19:02
Condition assessment using structural system identification Lei, Jun; Lozano-Galant, José Antonio; Nogal Macho, María; Xu, Dong; Turmo Coderque, José The accumulation of progressive deterioration of structures might lead to the failure of structures. In order to avoid potential accidents, it is important to carry out condition assessment using structural system identification. This is based on the assumption that damage of structures can be reflected in the change of parameters. In every SSI method, measurement errors are introduced in the process of data collection and simulation errors also exist due to the inherent property of the algorithm used. The observability method has been proposed to deal with structural system identification under static loadings. Up to now, error analysis for this method has not been addressed yet. To fill this gap, this paper evaluate the effects of measurement errors and simulation errors on the observability method. The effects of measurement errors in a specific measurement and in all measurements are considered. The result indicate that the loading case and the location of the measrement is of primary importance. Also, rotations are less sensitive to errors than vertical deflections. On the other hand, the error propogation during the identification regarding the recursive steps and the curvature of structure is also illustrated.
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Optical label-free nanoplasmonic biosensing using a vertical-cavity surface-emitting laser and charge-coupled device

UPCommons - dt., 12/05/2017 - 18:49
Optical label-free nanoplasmonic biosensing using a vertical-cavity surface-emitting laser and charge-coupled device Hedsten, Karin; Fonollosa Magrinyà, Jordi; Enoksson, Peter; Modh, Peter; Bengtsson, Jörgen; Sutherland, Duncan; Dmitriev, Alexander
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Quality coding by neural populations in the early olfactory pathway: analysis using information theory and lessons for artificial olfactory systems

UPCommons - dt., 12/05/2017 - 18:44
Quality coding by neural populations in the early olfactory pathway: analysis using information theory and lessons for artificial olfactory systems Fonollosa Magrinyà, Jordi; Gutiérrez-Gálvez, Agustín; Marco, Santiago
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Algorithmic mitigation of sensor failure: is sensor replacement really necessary?

UPCommons - dt., 12/05/2017 - 18:37
Algorithmic mitigation of sensor failure: is sensor replacement really necessary? Fonollosa Magrinyà, Jordi; Vergara, Alexander; Huerta, Ramon
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Limits to the integration of filters and lenses on thermoelectric IR detectors by flip-chip techniques

UPCommons - dt., 12/05/2017 - 18:33
Limits to the integration of filters and lenses on thermoelectric IR detectors by flip-chip techniques Fonollosa Magrinyà, Jordi; Carmona, Manuel; Santander, Joaquim; Fonseca, Luis; Moreno-Sereno, Mauricio; Marco, Santiago
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Ethylene optical spectrometer for apple ripening monitoring in controlled atmosphere store-houses

UPCommons - dt., 12/05/2017 - 18:30
Ethylene optical spectrometer for apple ripening monitoring in controlled atmosphere store-houses Fonollosa Magrinyà, Jordi; Halford, Bern; Fonseca, Luis; Santander, Joaquim; Udina, Sergi; Moreno-Sereno, Mauricio; Hildenbrand, Jürgen; Wöllenstein, Jürgen; Marco, Santiago
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Tensioning process update for cable stayed bridges

UPCommons - dt., 12/05/2017 - 18:21
Tensioning process update for cable stayed bridges Lozano-Galant, José Antonio; Turmo Coderque, José
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Construcció d'una passarel·la metàl·lica sobre el riu Mogent

UPCommons - dg., 12/03/2017 - 16:40
Construcció d'una passarel·la metàl·lica sobre el riu Mogent Varela Lora, Jesús Ignacio El present projecte inicialment estava centrat en l'ampliació del pont de la carretera BP-5002 sobre el riu Mogent, ja que aquest pont no disposa actualment de pas de vianants, però a causa de la dificultat d’execució d’aquesta ampliació sobre el pont, s'ha descartat per a la construcció d'una passarel·la paral·lela al pont existent. El propòsit del present projecte és el disseny, càlcul i dimensionat d'una passarel·la de vianants a la sortida del poble de Vilanova del Vallès, per a facilitar el pas de vianants sobre el riu Mogent i crear així una via de pas de vianants que comunica la zona industrial de Montornès del Vallès i la nova empresa que pertany a Vilanova del Vallès (Desguaces La Cabanya). Amb l'execució d'aquesta obra es pretén resoldre el problema que té el pont de la carretera BP- 5002 sobre el riu Mogent, que no disposa de pas de vianants. A més, la construcció d’un pas de vianants en la zona del projecte dóna facilitats de comunicació de les zones nord de Vilanova del Vallès, Montornès del Vallès i Montmeló amb el itinerari principal del poble de Vilanova del Vallès.
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Projecte Galileu Teen. La tecnologia a l’ESO i el desvetllament d’aptituds tecnològiques

UPCommons - dg., 12/03/2017 - 10:13
Projecte Galileu Teen. La tecnologia a l’ESO i el desvetllament d’aptituds tecnològiques Martínez Contreras, Susanna La matèria de tecnologia sovint és vista pels alumnes com a una assignatura que no acaben d'entendre i que els hi costa d'aprovar. En canvi, és una assignatura que els pot ajudar molt en el seu futur acadèmic i professional. El disseny d'activitats especifiques d'orientació acadèmica i professional a 3er d'ESO i 1er de Batxillerat, pot suposar un desvetllament de les aptituds tecnològiques de l'alumnat. El TFM parteix d'una primera fase de recerca d'informació sobre el sistema educatiu català en l'àmbit dels cicles formatius tant de grau mig com superior i dels graus universitaris relacionats amb la tecnologia. La metodologia de treball de camp a l'Institut és: una enquesta inicial, unes fitxes d'autoavaluació (material didàctic) i una enquesta final. L'objectiu és disposar d'una eina d'orientació acadèmica i professional.
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Implementation of optimization-based controllers in industrial processes

UPCommons - dv., 12/01/2017 - 20:40
Implementation of optimization-based controllers in industrial processes Ibáñez López, Carlos This thesis presents and discusses the possibility of the use of online model predictive control as the control strategy, embedded in an educational device from National Instruments. The work considers the use of different optimization solvers and code generators, which have come out in recent years by the academia, to control a four-tank pilot plant located in the Institut de Robòtica i Informàtica Industrial, CSIC-UPC. The mathematical model of the system, used to implement the optimization-based controllers, includes nonlinear dynamics, whereby two approaches have been discussed and implemented: linearizing the model around an operating point to design a linear predictive controller, and using the original nonlinear dynamics to design a nonlinear predictive controller. The experiments performed for the case studied shown the suitability of the obtained model to be used in the linear case, while less accuracy is obtained in the nonlinear case due to the approximation of the dynamics previously reported in the literature. Moreover, a possible implementation and embedding procedure for the designed controllers are both presented and discussed in detail. For the given implementation, an assessment between the solvers embedded in the real-time device is done, giving an evaluation of the suitability of each solver in the considered scenarios. Finally, this work opens different ways of future work not only in the adaptation of the dynamic model of the case studied, but also in the optimization of the software codes generated to design the real-time controllers.
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Can bus bootloader for the STM32F407VG

UPCommons - dv., 12/01/2017 - 20:12
Can bus bootloader for the STM32F407VG Landeo Márquez, Ricardo José The main objective of this project is to develop a Python application to transfer files in Intel hex format from a PC to a single STM32F407VG microcontroller using Can Bus protocol. The USB-Can adapter/converter used for this purpose is the leaf light HS from Kvaser. The microcontroller has to run in boot system mode to be able to reprogram the flash memory by using CAN. The boot from system memory is provided by STMicroelectronics. The application of this project is intended to allow working with the whole STM32 family but it was only tested with the mentioned device. There are some restrictions in the embedded boot system that entails some limitations in the program functioning: the built-in bootloader from ST is fixed for all microcontroller, what means that if we want to program more than one microcontroller we have to connect them one by one to the Can interface. The flash memory can only be written when it is erased but the flash erase command is not supported by the manufacturer. In this project we describe an alternative way to erase the flash memory prior the programming. The second part of this project is related to the design and development of an application based on the Python Tkinter module to create a graphic user interface (GUI) to make the program ease to use. This program utilizes the class developed in the previous application and it is separated from it to facilitate modifications or improvements by other developers.
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Anàlisi, experimentació i millora d'un sistema de ciber-seguretat de la llar Crowdsourced

UPCommons - dv., 12/01/2017 - 20:01
Anàlisi, experimentació i millora d'un sistema de ciber-seguretat de la llar Crowdsourced González Quevedo, Edgar Aquest projecte consisteix en l’anàlisi, experimentació i millora de CommunityGuard, un sistema de ciber-seguretat col·laboratiu aplicable a xarxes industrials, empresarials i domèstiques. CommunityGuard consisteix, en essència, en un dispositiu que resideix entre el “router” de la xarxa i el cable mòdem d’enllaç extern, i que es connecta a un sistema en núvol, al qual hi ha connectats més dispositius com aquest. El sistema automàticament escolta i monitoritza els paquets d’informació que accedeixen o surten de la xarxa amb l’objectiu de trobar activitat sospitosa i proporcionar una resposta adequada per tal de rebutjar satisfactòriament els atacs. Per a fer aquest projecte el primer pas ha estat la definició d’especificacions, com el nombre de nodes guardians o el tràfic maliciós a bloquejar. Després, s’ha analitzat i recreat CommunityGuard en un servidor, per tal d’entendre els aspectes més importants del seu funcionament. Això s’ha fet mitjançant màquines virtuals i respectant les especificacions originals. En aquesta etapa, s’observa que hi ha certs aspectes del codi de CommunityGuard que no estan acabats o que presentaven certs errors, i es corregeixen per acabar d’implementar-lo. D’altra banda, s’han realitzat proves per comprovar si el software utilitzat per a detectar tràfic maliciós, anomenat Snort, presenta un efecte negatiu en el rendiment de la xarxa. Els resultats de les proves demostren que l’efecte que causa és mínim, i que per tant no hi ha necessitat d’optimització en aquest sentit. La següent etapa del projecte és una ampliació de CommunityGuard. L’ampliació consisteix en un sistema orientat a la seguretat dels dispositius IoT d’una xarxa. El sistema conserva la figura del node guardià i afegeix la figura d’una persona. Els dispositius IoT de la xarxa han de demanar autorització al node guardià per a realitzar qualsevol acció nova, i la persona s’encarrega de donar resposta manualment a les noves sol·licituds. Aquest projecte, realitzat a la Universitat de Colorado, Boulder, gràcies a la beca Balsells i sota la direcció del professor Eric Keller, ha assolit satisfactòriament els objectius proposats. S’ha aconseguit que CommunityGuard funcioni correctament, i s’ha implementat una millora del mateix que incrementa la seguretat dels dispositius IoT. A l’annex F s’inclou una carta de valoració escrita pel professor Eric Keller.
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Study and implementation of a PMSM & Study of a sensorless control method

UPCommons - dv., 12/01/2017 - 19:50
Study and implementation of a PMSM & Study of a sensorless control method Beltran I Feliu, Helena The procedure followed in the project begins with a brief introduction of the features that the studied motor, a permanent magnet synchronous motor (PMSM), has. The fact that the motor is synchronous permanent magnet has to do with its greater efficiency in comparison with the induction motor, which is the most used nowadays. Then, the project is conducted in two steps. The first one is the study of the PMSM mathematical modelling and the subsequent control method applied. The second one is the study of a sensorless control algorithm. Traditionally for speed dependent applications, some kind of sensor is used to read the motor speed and position and feed the value back to the controller. However, extra sensors require extra physical space in the application and it also introduces another source of failure in the system. Thus, with the additional purposes of reducing cost and maintenance needs, the sensor can be replaced by an estimator that mathematically estimates the speed or position of the rotor. All these implementations have been simulated with MATLAB/Simulink based on the mathematical models. To design a controlled drive, the stability characteristics of PMSM under open-loop control (without having any feedback for speed) are analysed. The analysis shows that the PMSM becomes unstable after exceeding a certain applied speed. After tuning the controllers, it has been analysed that the maximum speed that the closed-loop can control with a reasonable settling time is 750 rpm. The more speed that the motor achieves, the more settling time appears. Thus, there is an upper limit for the speed. For all the simulations, an optimal speed of 550 rpm has been used. The control structure and the design of the controllers are described. A rotor position estimation technique for sensorless operation is studied. The estimator uses predictor-corrector method where the difference between the estimated current and the measured current (current error) is used to correct a predicted rotor position. More investigations are still required for accurate rotor position estimation.
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