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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
191

Détection des émotions à partir de vidéos dans un environnement non contrôlé / Detection of emotions from video in non-controlled environment

Khan, Rizwan Ahmed 14 November 2013 (has links)
Dans notre communication quotidienne avec les autres, nous avons autant de considération pour l’interlocuteur lui-même que pour l’information transmise. En permanence coexistent en effet deux modes de transmission : le verbal et le non-verbal. Sur ce dernier thème intervient principalement l’expression faciale avec laquelle l’interlocuteur peut révéler d’autres émotions et intentions. Habituellement, un processus de reconnaissance d’émotions faciales repose sur 3 étapes : le suivi du visage, l’extraction de caractéristiques puis la classification de l’expression faciale. Pour obtenir un processus robuste apte à fournir des résultats fiables et exploitables, il est primordial d’extraire des caractéristiques avec de forts pouvoirs discriminants (selon les zones du visage concernées). Les avancées récentes de l’état de l’art ont conduit aujourd’hui à diverses approches souvent bridées par des temps de traitement trop couteux compte-tenu de l’extraction de descripteurs sur le visage complet ou sur des heuristiques mathématiques et/ou géométriques.En fait, aucune réponse bio-inspirée n’exploite la perception humaine dans cette tâche qu’elle opère pourtant régulièrement. Au cours de ces travaux de thèse, la base de notre approche fut ainsi de singer le modèle visuel pour focaliser le calcul de nos descripteurs sur les seules régions du visage essentielles pour la reconnaissance d’émotions. Cette approche nous a permis de concevoir un processus plus naturel basé sur ces seules régions émergentes au regard de la perception humaine. Ce manuscrit présente les différentes méthodologies bio-inspirées mises en place pour aboutir à des résultats qui améliorent généralement l’état de l’art sur les bases de référence. Ensuite, compte-tenu du fait qu’elles se focalisent sur les seules parties émergentes du visage, elles améliorent les temps de calcul et la complexité des algorithmes mis en jeu conduisant à une utilisation possible pour des applications temps réel. / Communication in any form i.e. verbal or non-verbal is vital to complete various daily routine tasks and plays a significant role inlife. Facial expression is the most effective form of non-verbal communication and it provides a clue about emotional state, mindset and intention. Generally automatic facial expression recognition framework consists of three step: face tracking, feature extraction and expression classification. In order to built robust facial expression recognition framework that is capable of producing reliable results, it is necessary to extract features (from the appropriate facial regions) that have strong discriminative abilities. Recently different methods for automatic facial expression recognition have been proposed, but invariably they all are computationally expensive and spend computational time on whole face image or divides the facial image based on some mathematical or geometrical heuristic for features extraction. None of them take inspiration from the human visual system in completing the same task. In this research thesis we took inspiration from the human visual system in order to find from where (facial region) to extract features. We argue that the task of expression analysis and recognition could be done in more conducive manner, if only some regions are selected for further processing (i.e.salient regions) as it happens in human visual system. In this research thesis we have proposed different frameworks for automatic recognition of expressions, all getting inspiration from the human vision. Every subsequently proposed addresses the shortcomings of the previously proposed framework. Our proposed frameworks in general, achieve results that exceeds state-of-the-artmethods for expression recognition. Secondly, they are computationally efficient and simple as they process only perceptually salient region(s) of face for feature extraction. By processing only perceptually salient region(s) of the face, reduction in feature vector dimensionality and reduction in computational time for feature extraction is achieved. Thus making them suitable for real-time applications.
192

A Física dos movimentos analisada a partir de vídeos do cotidiano do aluno : uma proposta para a oitava série

Calloni, Gilberto José January 2010 (has links)
Este trabalho propõe introduzir conteúdos de Física, de modo a torná-los atrativos para alunos de 8ª série, através do estudo de situações divertidas, como os movimentos presentes em atividades esportivas e de lazer do seu cotidiano. Os movimentos foram filmados pelos alunos utilizando uma câmera fotográfica digital e, após, foi usado um programa de análise de imagens (Tracker). A escolha dos temas a serem filmados e analisados partiu de sugestões dos próprios alunos em sala de aula, orientados pela professora de Ciências e pelo autor dessa proposta de trabalho. As filmagens foram realizadas pelos alunos no pátio e no salão esportivo da escola; a análise dos movimentos filmados e sua descrição foram realizadas no laboratório de informática. A proposta foi aplicada no Colégio São José, de Caxias do Sul, RS, com cinco turmas de oitava série na disciplina de Ciências, durante os meses de setembro a novembro de 2008, inserindo as atividades paralelamente à apresentação dos conteúdos. Todo material desenvolvido e utilizado nesta proposta foi disponibilizado, gradualmente, no decorrer de sua aplicação na página Web do Colégio. O planejamento e a execução desta proposta foram embasados na teoria interacionista de Lev Vygotsky. Essa escolha se deu, principalmente, pelos objetivos pretendidos neste trabalho que previam que os alunos trabalhassem em grupo com a mediação dos professores, proporcionando e estimulando o gosto por aprender. A avaliação da proposta foi feita pelos alunos no final de sua aplicação através de um questionário de opinião. Segundo as respostas dos alunos, na medida em que atividades e tecnologias do seu cotidiano são utilizadas nas aulas de Física, faz com que essas se tornem mais motivadoras e interessantes. O material instrucional produzido, acompanhado de um guia de informações e orientações será publicado na série “Hipermídias de Apoio ao Professor de Física”, onde serão descritos os objetivos, a justificativa e a metodologia utilizados, com o intuito de que possam ser aplicados por outros professores associados à disciplina de Ciências da 8ª série. / This work proposes an alternative introduction of 8th grade Physics school contents through the study of Kinematics concepts present, e.g., in the students' daily sporting and leisure activities, in order to make these concepts more attractive and motivating to them. The situations have been registered in the schoolyard and gymnasium by the students themselves using a digital camera. The videoclips were then analyzed using an image analysis software (Tracker) in the school's computer laboratory. The subjects on the videoclips were selected among students' suggestions and assisted by the Science class teacher together with the author. The proposal has been carried out in Colégio São José, of Caxias do Sul, RS, with five different groups of 8th graders during Science classes, from September to November of 2008, these activities being alternated with regular classes. All material developed and used in the proposal was made available, during its application, on the School's Webpage. The planning and execution of this proposal are oriented along the social interaction theory of Lev Vygotsky. This choice is mainly motivated by the goal of promoting collaborative students work, intermediated by the teachers, providing and stimulating the taste for learning. The students evaluated the work by its conclusion through an opinion questionnaire. According to the students' answers to the questionnaire, when their daily activities were introduced in the Physics classes making use of available technology through electronic and computer devices, the Physics learning was rendered more interesting and motivating. The instructional material produced during the project application together with an information guide orienting other 8th grade Science teachers on its application will be published in the series “Hipermídias de Apoio ao Professor de Física”, where aims and methodology will also be described.
193

La physique des (di)muons dans ALICE au LHC : analyse en collisions pp (√s = 7 TeV) et Pb-Pb (√sNN = 2.76 TeV) des résonances de basses masses (ρ, ω, ф) et étude d’un trajectographe en pixels de Silicium dans l’ouverture du spectromètre / The (di)muon physics in the ALICE experiment at the LHC : light vector meson analysis (ρ, ω, ф) in pp collisions (√s = 7 TeV), Pb-Pb collisions (√sNN = 2.76 TeV) and study of a new silicon tracker in the muon spectrometer acceptance

Massacrier, Laure 26 October 2011 (has links)
L’expérience ALICE au LHC étudie le plasma de quarks gluons (PQG), état de la matière où quarks et gluons existent à l’état déconfinés. Une des sondes utilisée pour explorer cet état est l’étude de plusieurs résonances (ρ, ω, ф, J/ψ et Ƴ) via leur canal de désintégration dimuonique, à l’aide d’un spectromètre à muons couvrant les pseudo-rapidités -4 < η < -2.5. La première partie de la thèse se focalise sur les mésons vecteurs de basses masses (ρ, ω et ф) . Elle concerne l’analyse des données récoltées en 2010 en collisions pp à √s = 7 TeV et Pb-Pb à √sNN = 2.76 TeV. Les mésons vecteurs de basses masses sont des outils intéressants pour sonder le PQG grâce à leurs faibles durées de vie et leur canal de désintégration dimuonique non affecté par les interactions dans l’état final. Les taux de production et fonctions spectrales de ces mésons sont modifiées par le milieu hadronique chaud et le PQG. En collisions pp, les distributions du ф, du (ρ+ω) en fonction de l’impulsion transverse ainsi que les sections efficaces et sections efficaces différentielles de production des différents mésons ont été extraites. L’analyse en collisions Pb-Pb ainsi que ses perspectives sont également présentées. La seconde partie de la thèse concerne le futur de l’expérience ALICE et les plans d’amélioration des détecteurs pour l’horizon 2017. Une étude de faisabilité pour l’ajout d’un trajectographe en pixels de Silicium (MFT) à l’avant de l’absorbeur hadronique dans l’acceptance du spectromètre à muons est présentée. Les performances et améliorations apportées par le MFT dans différents canaux de physique ont été étudiées en simulation / ALICE experiment at LHC studies the Quark Gluon Plasma (QGP), a particular state of matter where quarks and gluons are deconfined. A probe to explore this state is the study of several resonances (ρ, ω, ф, J/ψ and Ƴ) through their dimuon decay channel, with a muon spectrometer covering pseudo-rapidity -4 < η < -2.5. In the first part of this thesis, the focus is on light vector mesons (ρ, ω and ф) and their analysis in the 2010 data, in pp collisions at √s = 7 TeV and Pb-Pb collisions at √sNN = 2.76 TeV. Light vector mesons are powerful tools to probe the QGP due to their short lifetime and their dimuon decay channel. Indeed, leptons have negligible final state interactions. Production rates and spectral functions of those mesons are modified by the hot hadronic and QGP medium. In pp collisions, pT distributions, production cross sections and pT-differential cross sections of the different mesons have been extracted. The Pb-Pb analysis and its prospects are also presented. The second part of the thesis concerns ALICE upgrades plans of year 2017. A feasibility study for a Muon Forward Tracker (MFT) in Silicon pixels located upstream of the hadronic absorber, in the spectrometer acceptance, was performed. Performances and improvements brought by the MFT on several physics cases were in simulations
194

New Theoretical And Experimental Studies On Spacecraft Attitude Determination Using Star Sensors

Rao, Goparaju Nagendra 03 1900 (has links) (PDF)
No description available.
195

Mechanical Study of Silicon Strip Detector Modules During Quality Control for the ATLAS Phase-II Detector Upgrade

Demontigny, Gabriel 03 1900 (has links)
Suite à la détection du très attendu boson de Higgs, le Grand Collisionneur de Hadrons (LHC) ainsi que le détecteur ATLAS se prépare pour une importante mise à niveau. Prévu pour le LHC à Haute Luminosité (HL-LHC), le ITk (Inner TracKer), un trajectomètre pour particules chargées fait de silicium, est la mise à niveau du détecteur interne du détecteur ATLAS. Une phase de test des modules de détecteur du ITk est cruciale puisque le détecteur sera inaccessible pour environ 10 ans suite à l’installation. Ce mémoire se concentrera sur les tests effectués sur un sous-ensemble du détecteur ITk, soit le détecteur ITk Strip. Pour détecter les bris prématurés sur les 20 000 modules qui seront produits, une procédure de cyclage thermique sera mise en oeuvre, où les modules seront refroidis et réchauffés pour recréer les 10 ans d’opération. Ces tests seront effectués dans une enceinte appelé coldbox. Le thème de ce mémoire est le calcul du stress mécanique dans les modules ITk Strip induit par la procédure de cyclage thermique à l’aide de la méthode des éléments finis. Le premier résultat obtenu est que le stress induit dans le module installé dans le coldbox est causé par le vide appliqué sous le module pour le tenir en place. De plus, le stress maximal durant le cyclage thermique est grandement dépendant de l’épaisseur du joint sous-vide utilisé. Ainsi, un joint plus mince cause un stress plus faible. Finalement, le stress dans le coldbox est entre 20 MPa et 100 MPa variant avec l’épaisseur du joint, ce qui est en accord avec le stress calculé pour une disposition semblable au détecteur final, donnant un stress de 64.8MPa. Il est donc possible de conclure que le coldbox est un bon candidat pour effectuer le cyclage thermique. / Following the great achievement by the ATLAS experiment at the Large Hadron Col- lider (LHC) that is the detection of the long-awaited Higgs boson, an upgrade of the LHC is planned, requiring an upgrade of ATLAS. Planned for the High-Luminosity LHC, the ITk (Inner TracKer), an all-silicon charged particle tracker, is the upgrade of the current ATLAS Inner Detector. Testing of the detector modules comprised in the ITk is crucial because the detector will be inaccessible for approximately 10 years following the installation. In this thesis, the focus will be kept on a subset of the ITk detector, namely the ITk Strip detector. To detect premature failure in the 20 000 Strip modules that will be produced, a series of tests will be performed, one of which will be the thermal cycling, where modules are monitored while being thermally cycled to replicate 10 years of operating conditions. These tests will occur in a special enclosure known as a coldbox. The subject of this work is to study the induced mechanical stress in future ITk Strip detector modules due to thermal cycling using Finite Element Analysis. Our first result is that the stress created in the module is mostly due to the vacuum applied to hold the module. Moreover, the maximum stress felt during thermal cycling is highly dependent on the thickness of the vacuum seal used: A thinner seal causes a lower stress. Finally, the stress in the module in our thermal cycling setup is between ∼ 20 MPa and ∼ 100 MPa depend- ing on the selected seal thickness, which is consistent with the stress expected in the final detector design which is approximately 64.8MPa. We can then conclude that the proposed design for the coldbox is a good candidate to perform thermal cycling.
196

Návrh a realizace mobilní fotovoltaické elektrárny / Design and Realization of Mobile Photovoltaic Power Station

Lednický, Ján January 2017 (has links)
This diploma thesis entitled Design and realization of a mobile photovoltaic power plant is dividet into two parts. In the first, theoretical part one can learn about the state of representation of renewable energy sources in the field of electrical power engineering and about the structure of photovoltaic power station systems. The secont part of this thesis is focused on the own design and realization of the mobile photovoltaic power plant, on the selection of individual suitable components and ther dimensioning. In addition, a model of a mobile power plant has been created, on the basis of which the power plant was constructed. Finally, one can find a source code analysis of a power plant monitoring using a microcontroler
197

Monitorování peerů sdílejících torrenty / Torrent Peer Monitoring

Bezděk, David January 2018 (has links)
This master's thesis deals with analysis and implementation of methods for BitTorrent monitoring focusing on the Mainline DHT protocol. The aim of the thesis was to create a system, that will be looking for BitTorrent peers that participe in the illegal file distribution. Another task of the system was to collect and analyze data for counting size of the BitTorrent network. That was achieved by taking over of existing method. The system was designed and implemented as a module for monitoring of cybernetic crime. It also defines an interface for storing and sharing data, that provides data evaluation, easy data manipulation and serves for possible future extensions.
198

Åtgärder för ökad markanvändning i solcellspark : En tekno-ekonomisk fallstudie om potentialen hos bifacial och solföljare i Solpark Fyrislund

Majid, Safwat January 2021 (has links)
Solar parks are increasingly getting a larger market share of PV installations over the world, and have for the last couple of years managed to establish itself in the Swedish market. The market has for a long time been known for its decline in module prices, which has allowed an emergence of more efficient PV-techniques such as one-axis trackers and bifacial modules. Bifacial modules use the backside of modules for improved utiliziation of incoming light, while one-axis trackers have the ability to track the sun in order to maximise light absorption. These innovations have now caught the interest of companies willing to invest in large-scale PV-farms, where efficient land use is highly regarded. The aim of this thesis was to examine how bifacial modules and one-axis trackers perform in terms of system performance and profitabilty if implemented in 'Solpark Fyrislund', a solar park owned by Vasakronan AB. This was done by modelling and simulating cases in which said techniques were incorporated. The data was later used to estimate profitabilty of each investigated case. Results showed that the highest system performance and profitability was achieved by installing bifacial modules on the site. One-axis trackers are currently too expensive, require higher maintenance and has a higher demand for land, resulting in its profitability not being justified. It was also found that the current configuration could be optimized further for higher profit, by slightly reducing the pitch as well as increasing the tilt of the existing modules. The study should be followed up by further investigating the use of backtracking for one-axis trackers. Said innovations should also be more established in the Swedish market so that CAPEX- and OPEX prices become more accessible.
199

Development and Evaluation of New Methods for Automating Experiments with C. Elegans Based on Active Vision

Puchalt Rodríguez, Joan Carles 10 March 2022 (has links)
Tesis por compendio / [ES] Esta tesis se centra en el desarrollo de nuevas técnicas automatizadas que permiten inspeccionar nematodos Caenorhabidits elegans (C. elegans) en placas de Petri estándar, para el análisis de sus comportamientos. C. elegans es un nemátodo de 1mm de longitud, con el cual se pueden realizar distintos experimentos para analizar los efectos de fármacos, compuestos o alteraciones genéticas en su longevidad, su salud física o su cognición. El campo principal metodológico del presente trabajo para el análisis de esos efectos es la visión por computador; y con ello, el desarrollo completo del sistema de visión activo: sistema de iluminación inteligente, sistema de captura óptimo, procesamiento de las imágenes para detección y clasificación de nematodos. Los campos secundarios en esta investigación son el control y robotización. Los C. elegans son animales sensibles a la luz y por ello el primero de los métodos está en la rama de la iluminación inteligente, con el cual se permite regular la intensidad y las longitudes de onda de la luz que reciben los nematodos. El siguiente método es el procesado para la detección y clasificación de movimiento a partir de las imágenes obtenidas con esa iluminación controlada. Tener el ambiente controlado es fundamental, los nematodos son muy sensibles a las condiciones ambientales por lo que puede alterarse su actividad biológica, y con ello los resultados, así que el tercer método es la integración de las técnicas en un nuevo dispositivo que permite automatizar ensayos de lifespan y validar los resultados automáticos comparándolos con los manuales. El movimiento del animal es clave para poder realizar inferencias estadísticas que puedan mostrar tendencias en sus comportamientos, por ello la estimulación automatizada que provoque una reacción de su movilidad es el cuarto de los métodos. Por último, el aumento de la resolución en las imágenes muestra mayor detalle, mejorando el procesamiento y extracción de características. El quinto método es un robot multivista que posibilita tomar imágenes a distintas resoluciones, lo que permite mantener el seguimiento global de los gusanos, al mismo tiempo que se toman imágenes con un encuadre de mayor detalle del nematodo objetivo. / [CA] Esta tesi doctoral se centra en el desentrollament de noves tècniques automatitzades que permeten inspeccionar nemàtodes Caenorhabidits elegans (C. elegans) en plaques de Petri estàndar, per a l'anàlisi dels seus comportaments. C. elegans és un nemàtode d'1mm de llargària, ab el qual se poden realitzar distints experiments per a analitzar els efectes de fàrmacs, composts o alteracions genètiques en sa longevitat, la seua salut física o la seua cognició. El camp principal metodològic del present treball per a l'anàlisi d'eixos efectes és la visió per computador; i ab açò, el desentrollament complet del sistema de visió actiu: sistema d'il.luminació inteligent, sistema de captura òptim, processament de les imàtgens per a detecció i classificació de nematode. Els camps secundaris en esta investigació són el control i robotització. Els C. elegans són animals sensibles a la llum i por ello el primer dels mètodes està en la branca de la il.luminació intel.ligent, ab el qual es permet regular la intensitat i les longituds d'ona de la llum que reben els nematodes. El següent mètode és el processat per a la detecció i classificació de moviment a partir de les imàtgens obtinguda ab eixa il.luminació controlada. Tindre l'ambient controlat és fonamental, els nemàtodes són molt sensibles a les condicions ambientals per lo que pot alterar-se la seua activitat biològica, i ab aço els resultats, aixina que el tercer mètode és la integració de les tècniques en un nou dispositiu que permet automatitzar ensajos de lifespan i validar els resultats automàtics comparant-los ab els manuals. El moviment de l'animal és clau per a poder realitzar inferencies estadístiques que puguen mostrar tendències en el seus comportaments, per això la estimulació automatitzada que provoque una reacció de la seua mobilitat és el quart dels mètodes. Per últim, l'augment de la resolució en les imàtgens mostra major detall, millorant el processament i extracció de característiques. El quint mètode és un robot multivista que possibilita prendre imàtgens a distintes resolucions, lo que permet mantindre el seguiment global dels cucs, al mateix temps que se prenguen imàtgens ab un enquadrament de major detall del nematode objectiu. / [EN] This thesis focuses on the development of new automated techniques that allow the inspection of Caenorhabidits elegans nematodes (C. elegans) in Petri dishes, for the analysis of their behavior. This nematode is a 1mm long worm, with which different experiments can be carried out to analyze the effects of drugs, compounds or genetic alterations on its longevity, physical health or cognition. The main methodological field of the present work for the analysis of these effects is computer vision; and with it, the complete development of the active vision system: intelligent lighting system, optimal capture system, image processing for detection and classification of nematodes. The secondary fields in this research are control and robotization. C. elegans are light-sensitive animals and therefore the first method is in the field of intelligent lighting, with which it is possible to regulate the intensity and wavelength of the light that nematodes receive. The next method is the processing for the detection and classification of movement from the images obtained with that controlled lighting. Having a controlled environment is essential, worms are very sensitive to environmental conditions so it can alter biological activity, and with it the results, so the third method is the integration of techniques in a new device that allows automating tests of lifespan and validate the automatic results comparing them with the manual ones. The movement of the animal is key to be able to carry out statistical conferences that can show trends in its behaviors, therefore the automated stimulation that causes a reaction of its mobility is the fourth of the methods. Finally, increasing the resolution in the images shows greater detail, improving the processing and extraction of features. The fifth method is a multiview robot that enables images to be taken at different resolutions, allowing global tracking of worms to be maintained, while at the same time taking images with a more detailed frame of the target worm. / Puchalt Rodríguez, JC. (2022). Development and Evaluation of New Methods for Automating Experiments with C. Elegans Based on Active Vision [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/181359 / TESIS / Compendio
200

Developing preclinical devices for neuroscience research in the fields of animal tracking, fMRI acquisition, and 3D histology cutting

Quiñones Colomer, Darío Rubén 27 March 2019 (has links)
[ES] La neurociencia es un campo que abarca muchas especialidades. El objetivo de esta tesis es subsanar algunas carencias tecnológicas que existen en los métodos actuales de experimentación animal en neurociencia. En esta tesis, se presentan seis proyectos, que tendrán como objetivo mejorar el "Principio de las tres R", el cual fue enunciado por los biólogos ingleses W. M. S. Russell y R. L. Burch, durante la experimentación animal. El comportamiento es uno de los aspectos más importantes de la vida animal. Depende de los vínculos entre los animales, sus sistemas nerviosos y sus entornos. Para estudiar el comportamiento de los animales de laboratorio, se necesitan varias herramientas, pero una herramienta de seguimiento es esencial para llevar a cabo un estudio de comportamiento exhaustivo. Varias herramientas de seguimiento visual están actualmente disponibles. Sin embargo, todas tienen algunos inconvenientes. Por ejemplo, en una situación en la que un animal está dentro de una madriguera o cerca de otros animales, las cámaras de rastreo (tracking) no siempre pueden detectar la ubicación precisa o el movimiento del animal. Por esta razón, los entornos enriquecidos para intentar recrear el hábitat natural de los animales en experimentación no pueden utilizarse, ya que los datos recopilados son insuficientes/inexactos. Con la finalidad de mejorar los experimentos de tracking RFID Assisted Tracking Tile (RATT) es presentado en esta tesis. RATT es un sistema de seguimiento basado en tecnología de identificación pasiva de radiofrecuencia (RFID) y está compuesto por baldosas electrónicas con las que se puede construir una gran superficie, sobre la cual los animales pueden moverse libremente. Esto permite la identificación más precisa de los animales, así como el seguimiento de sus movimientos. Este sistema, que también se puede combinar con un sistema de seguimiento con cámaras, allana el camino para estudios completos de comportamiento en entornos enriquecidos. Dada la capacidad de rastrear animales y, por lo tanto, realizar experimentos de comportamiento exhaustivos, es posible observar cómo se comportan los sujetos desde un punto de vista externo. Sin embargo, si queremos comprender lo que sucede en el cerebro de estos sujetos, es necesario aplicar otras técnicas de análisis, por ejemplo, el estudio de señales dependientes del nivel de oxígeno en la sangre (BOLD, por sus siglas en inglés). Las señales BOLD se basan en las respuestas vasculares a la activación neuronal y se utilizan ampliamente en estudios de investigación clínicos y preclínicos. En entornos preclínicos, los animales suelen ser anestesiados. Sin embargo, los anestésicos causan cambios en la fisiología de los animales, p. Ej. hipotermia, y esto tiene el potencial de alterar las señales funcionales de MRI (fMRI). Para evitar la hipotermia en roedores anestesiados, se presenta TherMouseDuino. Este es un sistema de control automático de temperatura de código abierto, que reduce las fluctuaciones de la temperatura, lo que proporciona condiciones sólidas para realizar experimentos de resonancia magnética funcional. En los cursos de biología y neurociencia, la anatomía del cerebro se enseña generalmente utilizando imágenes de resonancia magnética (IRM) o secciones histológicas de diferentes planos. Estos muestran las áreas macroscópicas más importantes en el cerebro de un animal. Sin embargo, este método no es dinámico ni intuitivo. En esta tesis se presenta un cerebro de rata impreso en 3D con fines educativos. La manipulación manual de la estructura, facilitada por la ampliación de sus dimensiones, junto con la capacidad de desmontar el "cerebro" en algunas de sus partes principales, facilita la comprensión de la organización 3D del sistema nervioso. Este es un método alternativo y mejorado para enseñar a los estudiantes en general y a los biólogos, en particular, la anatomía del cerebro de rata. / [CA] La neurociència és un camp que abasta moltes especialitats. L'objectiu d'aquesta tesi és esmenar algunes manques tecnològiques que existeixen en els mètodes actuals d'experimentació animal en neurociència. En aquesta tesi, es presenten sis projectes, que tindran com a objectiu millorar el "Principi de les tres R", el qual va ser enunciat pels biòlegs anglesos W. M. S. Russell i R. L. Burch, durant l'experimentació animal. El comportament és un dels aspectes m'és importants de la vida animal. Depèn dels vincles entre els animals, els seus sistemes nerviosos i els seus entorns. Per estudiar el comportament dels animals de laboratori, es necessiten diverses eines, però` una eina de seguiment és essencial per a dur a terme un estudi de comportament exhaustiu. Diverses eines de seguiment visual estan actualment disponibles. No obstant això, totes tenen alguns inconvenients. Per exemple, en una situació en la qual un animal esta` dins d'un cau o prop d'altres animals, les cambres de rastreig (tracking) no sempre poden detectar la ubicació precisa o el moviment de l'animal. Per aquesta raó, els entorns enriquits per a intentar recrear l'hàbitat natural dels animals en experimentació no poden utilitzar-se, ja que les dades recopilades són insuficients/inexactes. Amb la finalitat de millorar els experiments de tracking/seguiment RFID Assisted Tracking Tile (RATT) és presentat en aquesta tesi. RATT es un sistema de seguiment basat en tecnologia d'identificació passiva de radiofreqüència (RFID) i esta` compost per rajoles electròniques amb les quals es pot construir una gran superfície, sobre la qual els animals poden moures lliurement. Això permet la identificació més precisa dels animals, així com el seguiment dels seus moviments. Aquest sistema, que també es pot combinar amb un sistema de seguiment amb cambres, aplana el camí per a estudis complets de comportament en entorns enriquits. Donada la capacitat de rastrejar animals i, per tant, realitzar experiments de comportament exhaustius, és possible observar com es comporten els subjectes des d'un punt de vista extern. No obstant això, si volem comprendre el que succeeix en el cervell d'aquests subjectes, és necessari aplicar altres tècniques d'anàlisis, per exemple, l'estudi de senyals dependents del nivell d'oxigen en la sang (BOLD, per les seues sigles en anglès). Els senyals BOLD es basen en les respostes vasculars a l'activació neuronal i s'utilitzen àmpliament en estudis d'investigació clínics i preclínics. En entorns preclínics, els animals solen ser anestesiats. No obstant això, els anestèsics causen canvis en la fisiologia de els animals, per exemple hipotèrmia, i això te el potencial d'alterar els senyals funcionals de MRI (fMRI). Per a evitar la hipotèrmia en rosegadors anestesiats, es presenta TherMouseDuino. Aquest és un sistema de control automàtic de temperatura de codi obert, que redueix les fluctuacions de la temperatura, la qual cosa proporciona condicions solides per a realitzar experiments de ressonància magnètica funcional. En els cursos de biologia i neurociència, l'anatomia del cervell s'ensenya generalment utilitzant imatges de ressonància magnètica (IRM) o seccions histològiques de diferents plans. Aquests mostren les àrees macroscòpiques més importants en el cervell de un animal. No obstant això, aquest mètode no és dinàmic ni intuïtiu. En aquesta tesi es presenta un cervell de rata imprès en 3D amb finalitats educatius. La manipulació manual de l'estructura, facilitada per l'ampliació de les seues dimensions, juntament amb la capacitat de desmuntar el "cervell" en algunes de les seues parts principals, facilita la comprensió de l'organització 3D del sistema nerviós. Aquest és un mètode alternatiu i millorat per a ensenyar a els estudiants en general i als biòlegs, en particular, l'anatomia del cervell de rata. / [EN] Neuroscience is a field that covers many specialties. The objective of this thesis is to correct some technological deficiencies that exist in current methods of animal experimentation in neuroscience. In this thesis, six projects are presented, which will aim to improve the "Principle of the three Rs" in animal experimentation enunciated by the English biologists W. M. S. Russell and R. L. Burch. In the present era of impressive progress in neuroscience, it is still not arguable that a complete understanding of the brain cannot be possible without a comparable understanding of animal behavior. In order to study the behavior of laboratory animals, various tools are needed, being a reliable tracking system one of the most important to follow large populations of individual subjects that interact in complex manners. Several visual tracking tools are currently available. However, they all have some drawbacks. For example, in a situation where an animal is inside a cave, or is in close proximity to other animals, tracking cameras cannot always detect the precise location or movement of the animal. For this reason, environments that have been enriched in order to attempt to recreate the natural habitat of the animals under experiment, cannot be used, as the data gathered is insufficient/inaccurate. In order to improve the current tracking systems , the RATT is presented. RATT is a tracking system based on passive RFID technology and it is composed of electronic tiles. Using several tiles, a large surface area, on which the animals can move freely, can be built. This enables the more accurate identification of the animals, as well as the tracking of their movements. This system, which can also be combined with a visual tracking system, paves the way for complete behavioral studies in enriched environments. Given the ability to track animals and thus conduct thorough behavioral experiments, it is possible to observe how the subjects behave from an external viewpoint. However, if we want to understand what is going on in the brains of these subjects, it is necessary to apply other analysis techniques, for example the study of BOLD signals. BOLD signals are based on vascular responses to neuronal activation and are used extensively in clinical and preclinical research studies. In preclinical settings, animals are usually anesthetized. However, anesthetics cause changes in the physiology of the animals, e.g. hypothermia, and this has the potential to disrupt fMRI signals. In order to avoid hypothermia in anesthetized rodents, TherMouseDuino is presented. This is an Open-Source automatic temperature control system, which reduces temperature fluctuations, thus providing robust conditions in which to perform fMRI experiments. In biology and neuroscience courses, brain anatomy is generally taught using MRI or histological sections of different planes. These show the most important macroscopic areas in an animals' brain. However, this method is neither dynamic nor intuitive. An anatomical 3D printed rat brain with educative purposes is presented in this thesis. Hand manipulation of the structure, facilitated by the scaling up of its dimensions, together with the ability to dismantle the "brain" into some of main its constituent parts, facilitates the understanding of the 3D organization of the nervous system. This is an alternative and improved method for teaching students in general and biologists, in particular, the rat brain anatomy. / This work was supported in part by the Spanish Ministerio de Economía y Competitividad (MINECO) and FEDER funds under grants BFU2015-64380-C2-2-R (D.M.) and BFU2015-64380-C2-1-R, by EU Horizon 2020 Program 668863-SyBil-AA grant (S.C.). S.C. acknowledges financial support from the Spanish State Research Agency, through the “Severo Ochoa” Programme for Centres of Excellence in R&D (ref. SEV-2013-0317) and by a grant “Ayudas para la formación de personal investigador (FPI)” from the Vicerrectorado de Investigación, Innovación y Transferencia of the Universitat Politècnica de València. / Quiñones Colomer, DR. (2019). Developing preclinical devices for neuroscience research in the fields of animal tracking, fMRI acquisition, and 3D histology cutting [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/118795 / TESIS

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