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Action learning in undergraduate engineering thesis supervision

  • Stappenbelt, Brad
In the present action learning implementation, twelve action learning sets were conducted over eight years. The action learning sets consisted of students involved in undergraduate engineering research thesis work. The concurrent study accompanying this initiative investigated the influence of the action learning environment on student approaches to learning and any accompanying academic, learning and personal benefits realised. The influence of preferred learning styles on set function and student adoption of the action learning process were also examined. The action learning environment implemented had a measurable significant positive effect on student academic performance, their ability to cope with the stresses associated with conducting a research thesis, the depth of learning, the development of autonomous learners, and student perception of the research thesis experience. The present study acts as an addendum to a smaller scale implementation of this action learning approach, applied to supervision of third and fourth year research projects and theses, published in 2010, Peer Reviewed
Proyecto:


Neutron capture cross section measurements at n_TOF of 237Np, 240Pu, 243Am, for the transmutation of nuclear waste

  • Calviño Tavares, Francisco
  • Cortés Rossell, Guillem Pere
  • Poch Parés, Agustí
  • Pretel Sánchez, Carme
Accurate and reliable neutron capture cross section data for actinides are necessary for the proper design, safety regulation and precise performance assessment of transmutation devices such as Fast Critical Reactors or Accelerator Driven Systems. In particular, the neutron capture cross sections of 237Np, 240Pu and 243Am play a key role in the design and optimization of strategies for the Transmutation of Nuclear Waste. The listed cross sections have been measured in 2004 at n_TOF [1] with a high accuracy due to a combination of features unique in the world: high instantaneous neutron fluence and excellent energy resolution of the n_TOF facility, innovative Data Acquisition System based on flash ADCs and the use of a high performance BaF2 Total Absorption Calorimeter as a detection device., Peer Reviewed
Proyecto:


L’architecture d’aujourd’hui, patrimoine de demain

  • Guerrouche, Kheir-eddine
Ponència presentada a: Session 9: Diseño e historia (modernidad y tradición) / Design and history (modernity and tradition)
Proyecto:


Smart city planning

  • Parra Albares, Marcos Íñigo
Es un problema cada día más grave la reducción de la calidad de vida en las principales ciudades debido a diferentes factores como la contaminación acústica y atmosférica, la pérdida de espacio de estancia, la pérdida de verde y biodiversidad, etc. Frente a estos factores, cada vez más gente se conciencia en la necesidad de implantar un modelo de ciudad más sostenible y amigable hacia los ciudadanos. Un claro ejemplo son los movimientos vecinales más actuales de Meridiana y Vía Layetana para pacificar el tráfico en Barcelona. El sistema de movilidad actual es la causa principal de estos problemas debido principalmente a su alta ocupación de espacio público, su baja sostenibilidad y su dominación sobre el urbanismo. La densidad de vehículos en la ciudad condal es muy superior al resto de ciudades europeas provocando unas 3000 muertes prematuras al año según Centre de Recerca en Epidemiología Ambiental (CREAL). Ha esto se le tiene que sumar numerosos ataques de asma, bronquitis, problemas cardiovasculares, el fomento de una vida sedentaria, falta de espacios verdes entre otros problemas. Debido a la densa edificación de las últimas décadas y la falta de espacios por consolidar, la única manera de mejorar esta situación es mediante la gestión del espacio público. Aumentar el espacio dedicado al ciudadano, al verde y a los modos de desplazamiento alternativos. En este punto es donde aparecen las pacificaciones del tránsito como único camino para la transformación de la ciudad. Con el presente estudio se busca, con la pacificación como única herramienta de trabajo, ampliar el material en este campo de una forma más cuantitativa al comparar diferentes urbanismos. Además se busca dar un salto en el campo de la pacificación al mirar este elemento como la celda de una red adaptable a toda la ciudad y no como un proyecto urbanístico puntual. Para ello se realizará una recopilación de diferentes guías existentes para la cuantificación de los diferentes factores presentes dentro de un proyecto urbanístico, a partir de las cuales se creará una guía básica que permita la comparación de los diferentes urbanismos a analizar., The reduction of the quality of life in the main cities is getting more serious every day. That is caused by different factors as the acoustic and atmospheric pollution, the reduction of space of stay, the fading of green and biodiversity, etcetera. Facing this, every time there are more conscious people who want a more sustainable and friendly, towards the citizens, city model. A clear example are the current neighbourhood movements of Meridiana and Vía Layetana to pacify the transit of Barcelona. The current mobility system is the cause of these problems because it takes an important part of public space, is not sustainable and dominates urbanism. The density of cars in the city of Barcelona is higher than in other European cities. This inflicts around 3000 premature deaths every year in accordance with the Centre de Recerca en Epidemiología Ambiental (CREAL). This inflicts also asthma attacks, bronchitis, cardiovascular problems, development of a sedentary life, lack of green spaces and other problems. Because of the dense edification of the latest decades and the lack of unconsolidated spaces, there is only one way to improve the situation through public space’s management. Improve the space for citizens, green space and alternative displacement modes. In this point, pacification of the traffic is the only way to transform the city. With this thesis, with the pacification as the unique tool, we seek to enlarge the material of this field with a quantitative study to compare different urbanisms. Furthermore, it tries to develop the idea of pacification from a punctual project to an element as a cell of a network for all the city. For this reason, this thesis recollects different guides to quantify the different factors featured within an urbanism project. From them a guide will be created to allow the comparison between the different urbanisms analysed.
Proyecto:


Sun sensors for small satellites attitude determination systems

  • Enrich Carmona, Álvaro
It is more and more obvious that nanosatellites are becoming key players to conduct all kinds of experiments; most of which will lead to the development of larger and more powerful systems, once the aforementioned nanosatellites experiments are proven valid. The ‘Teoria de la Senyal i les Comunicacions’ department of the Universitat Politècnica de Catalunya is currently developing and studying CubeSats for technology demonstration and as platforms of small scientific experiments. Given the fact that the satellite structure and capacity are not without limitations, all projects have to contemplate them to fulfill the requirements. Consequently, in this thesis, more economic devices that will also not take that much space in the nanosatellite are considered. This degree thesis presents the development of the whole Sun sensor subsystem of 3 CAT-4, the next UPC’s NanoSat Lab project. The circuit implementing the system is the same as the one that was previously designed in the “Projecte Avançat d’Enginyeria” subject. However, the integration in the CubeSat, the software to communicate with the on board computer and the estimation data software are implemented from scratch. The calibration system is improved, considering it was previously designed, and the software to perform it is also implemented from scratch. Overall, this thesis sheds light on how to develop a low-cost Sun sensor for a nanosatellite and the constrains that have to be taken into account when doing so., Cada cop més, resulta obvi que els nanosatèl·lits estan sent l’impuls per dissenyar tot tipus d’experiments que puguin arribar a desenvolupar sistemes molt m ́es potents, un cop provats i especialitzats els anteriors. El departament de Teoria del Senyal i les Comunicacions de la Universitat Politècnica de Catalunya està actualment estudiant i desenvolupant CubeSats per tal de demostrar tot tipus de tecnologies i com a plataformes per a petits experiments científics. Tenint en compte el fet que la pròpia estructura i la capacitat del satèl·lit suposen certes limitacions, tots els projectes les han de contemplar a l’hora de satisfer els seus requisits. En conseqüència, en aquesta tesi, són considerats els dispositius més econòmics i que puguin aprofitar al màxim l’espai dels nanosatèll·lits utilitzats. En aquest projecte es desenvolupa completament un subsistema “Sun Sensor” per al proper projecte del NanoSat Lab de la UPC, el 3 CAT-4. El circuit electrònic que implementa el sistema és el mateix que el dissenyat prèviament a l’assignatura de Projecte Avançat d’Enginyeria. No obstant, la integració del sistema al CubeSat, el software de comunicació amb l’ordinador a bord i el procés d’estimació de la direcció de la llum incident es dissenyen i implementen de zero. El sistema mecànic de calibratge es millora, ja que ja existia una primera versió dissenyada però el software per dur a terme el calibratge del sensor també s’implementa des de zero. En general, aquesta tesi dóna llum a com desenvolupar un “Sun sensor” de baix cost per nanosatèl·lits i les restriccions que s’han de tenir en compte per fer-ho., Cada vez resulta más obvio que los nanosatélites están siendo el impulso para diseñar todo tipo de experimentos que puedan llegar a desarrollar sistemas mucho más potentes, una vez probados y especializados los anteriores. El departamento de ”Teoria de la Senyal i les Comunicacions” de la Universitat Politècnica de Catalunya está actualmente estudiando y desarrollando CubeSats para demostrar todo tipo de tecnologías y como plataformas para pequeños experimentos científicos. Teniendo en cuenta el hecho de que la propia estructura y la capacidad del satélite suponen unas limitaciones, todos los proyectos deben contemplarlas para satisfacer sus requisitos. En consecuencia, en esta tesis, son considerados los dispositivos más económicos y que puedan aprovechar al máximo el espacio de los nanosatélites usados. En este Proyecto se desarrolla completamente un subsistema “Sun sensor” para el próximo proyecto del NanoSat Lab de la UPC, el 3 CAT-4. El circuito electrónico que implementa el sistema es el mismo que el diseñado previamente en la asignatura de “Projecte Avançat d’Enginyeria”. Sin embargo, la integración del sistema en el CubeSat, el software de comunicación con el ordenador de a bordo y el proceso de estimación de la dirección de la luz incidente se diseñan e implementan de cero. El sistema mecánico de calibración se mejora, ya que existía una primera versión diseñada, pero el software para llevar a cabo la calibración también se implementa de cero. En general, esta tesis da luz a como desarrollar un “Sun sensor” de bajo coste, para nanosatélites y las restricciones que deben tenerse en cuenta para llevarlo a cabo.
Proyecto:


Disseny i desenvolupament de serveis basats en beacons pel Campus del Baix Llobregat

  • Cabezas Alarcón, Marc
Beacons are devices of small dimensions and great autonomy that are based on the Bluetooth Low Energy technology to diffuse, within a range of up to 100 meters, a unique identifier and a range of parameters or data. If it is received by a compatible smartphone, this information allows to offer different services to any type of public. The objective of this paper is to verify the feasibility of integrating, in a mobile application, useful services based on beacons for the educational community of the Baix Llobregat Campus. Also, we pretend to document the technology on which these devices are based, in terms of hardware and software, in order to understand better their limitations and the opportunities they can offer in our application scenario among others. As a result of this paper, a number of services have been proposed and implemented in an application available on Google Play. The application, called beaconsUPC, has been developed with the Ionic framework, which has allowed us to program it with Web technologies (Typescript, Sass and HTML) and, thanks to that, an Android and iOS app has been made. In addition, the application has been validated from the attachment of beacons in some buildings of the Campus. The difficulty of using beacons lies in knowing what services are useful to customers. If that combination is achieved, many companies will have succeeded since, having a mobile application installed in customers' smartphones, allows such companies to have a direct communication. Consequently, they can improve their brand image and also obtain economic profitability, for example, by sending advertisings.
Proyecto:


Location of hot spots in integrated circuits by monitoring the substrate thermal-phase lag with the mirage effect

  • Perpiñà, Xavier
  • Altet Sanahujes, Josep
  • Jordà, Xavier
  • Vellvehi, Miquel
  • Mestres, Narcís
This Letter presents a solution for locating hot spots in active integrated circuits (IC) and devices. This method is based on sensing the phase lag between the power periodically dissipated by a device integrated in an IC (hot spot) and its corresponding thermal gradient into the chip substrate by monitoring the heat-induced refractive index gradient with a laser beam. The experimental results show a high accuracy and prove the suitability of this technique to locate and characterize devices behaving as hot spots in current IC technologies.
Proyecto:


A Method to Simultaneously Extract the Small-Signal Equivalent Circuit and Noise Parameters of Heterojunction Bipolar Transistors

  • Maya Sánchez, Mª del Carmen
  • Lázaro Guillén, Antoni
  • Pradell i Cara, Lluís
A method to extract the elements of the small-signal equivalent circuit and the noise parameters (NPs) of heterojunction bipolar transistors (HBTs) is presented. The extraction is done by simultaneous fitting of the measured S-parameters, noise figure (for a well-matched impedance), and NPs (estimated using the so-called F50 method). An additional error term, given by the root square sum of the differences between the NPs estimated from the F50 method and the NPs directly computed using the Hawkins model, is considered in order to avoid nonphysical results in the extraction of the intrinsic noise sources. To obtain the initial values of the equivalent-circuit elements, analytical expressions are applied under a number of bias conditions, namely, reverse bias, forward bias, and active bias. Experimental verification of the extraction of the equivalent-circuit elements and NPs of an HBT, up to 8 GHz, are presented, and the NPs are compared to those measured with an independent (tuner-based) method. The behavior of Fmin, extracted using the proposed method, as a function of the HBT collector current, is also presented., Peer Reviewed
Proyecto:


Cuestión de nombres

  • Barceló Garcia, Miquel
Proyecto:


Osteoinduction by foamed and 3D-printed calcium phosphate scaffolds: effect of nanostructure and pore architecture

  • Barba Serrahima, Albert
  • Díez Escudero, Anna
  • Maazouz, Yassine
  • Rappe, K.
  • Español Pons, Montserrat
  • Montufar Jiménez, Edgar Benjamin
  • Bonany Mariñosa, Mar
  • Sadowska, Joanna Maria
  • Guillem Martí, Jordi
  • Ohman, Caroline
  • Persson, Cecilia
  • Manzanares, Maria Cristina
  • Franch Serracanta, Jordi
  • Ginebra Molins, Maria Pau
Some biomaterials are osteoinductive, that is, they are able to trigger the osteogenic process by inducing the differentiation of mesenchymal stem cells to the osteogenic lineage. Although the underlying mechanism is still unclear, microporosity and specific surface area (SSA) have been identified as critical factors in material-associated osteoinduction. However, only sintered ceramics, which have a limited range of porosities and SSA, have been analyzed so far. In this work, we were able to extend these ranges to the nanoscale, through the foaming and 3D-printing of biomimetic calcium phosphates, thereby obtaining scaffolds with controlled micro- and nanoporosity and with tailored macropore architectures. Calcium-deficient hydroxyapatite (CDHA) scaffolds were evaluated after 6 and 12 weeks in an ectopic-implantation canine model and compared with two sintered ceramics, biphasic calcium phosphate and ß-tricalcium phosphate. Only foams with spherical, concave macropores and not 3D-printed scaffolds with convex, prismatic macropores induced significant ectopic bone formation. Among them, biomimetic nanostructured CDHA produced the highest incidence of ectopic bone and accelerated bone formation when compared with conventional microstructured sintered calcium phosphates with the same macropore architecture. Moreover, they exhibited different bone formation patterns; in CDHA foams, the new ectopic bone progressively replaced the scaffold, whereas in sintered biphasic calcium phosphate scaffolds, bone was deposited on the surface of the material, progressively filling the pore space. In conclusion, this study demonstrates that the high reactivity of nanostructured biomimetic CDHA combined with a spherical, concave macroporosity allows the pushing of the osteoinduction potential beyond the limits of microstructured calcium phosphate ceramics., Peer Reviewed
Proyecto:


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