Zugl.: Freiburg (Breisgau), Univ., Diss., 2009

Zugl.: Ilmenau, Techn. Univ., Diss., 2006

Cette recherche traite du phénomène immersif dans les mondes virtuels accessibles « grâce à » internet. Second Life sert de terrain d'analyse car il permet de discuter trois régimes immersifs : le perceptif, le narratif et le lien social. Au traversd'une approche formelle (Simmel) et de la théorie de l'acteur-réseau (ANT, Latour), nous analysons diverses médiations conditionnant ces régimes : les villes modélisées dans Second Life sont étudiées de façon approfondie comme le lieu duvivre ensemble et de l'hétérogénéité des publics et des usages.Notre thèse qui s'appuie sur la sociologie a également recours aux sciences de l'information et de la communication, à la philosophie, à la géographie de l'espace social et aux digital humanities. Il s'agit d'une approche transdisciplinaire sollicitant des matériaux variés : observations participantes, entretiens, questionnaires. Nous développons une techniqueautomatisée de « tracking » pour générer des « Big Data » permettant l'analyse des pratiques spatiales des avatars dans l'univers digital.Nous montrons que l'immersion dépend des choix de l'utilisateur (point de vue visuel, choix des activités, etc.) et des qualités et possibles de Second Life (architecture technique, carte du monde, forme du cadre bâti, etc.). Des phénomènes d'appropriation et d'attachement entre des acteurs et des lieux sont décrits et permettent de constater la formalisation d'un« chez-soi ». Les diverses étapes de ce travail contribuent à une théorie de l'habiter dans les mondes virtuels / This research deals with the phenomenon of immersion in virtual worlds which are accessible "thanks to" the internet. Second Life is used as fieldwork because it allows to discuss three immersion regimes: perceptive, narrative andsocial ones. Through a formal approach (Simmel) and actor-network theory (ANT, Latour), we analyze various mediations which condition these immersion regimes: cities modeled in Second Life are studied in depth as the place to live togetherand as heterogeneous audiences and uses.Our thesis which is based on sociology also uses information and communication sciences, philosophy, geography of social space, and digital humanities. It is a transdisciplinary approach using various methods: participant observations,interviews, questionnaires. We develop an automated tracker to generate "Big Data" for the analysis of spatial practices of avatars in the digital world.We show that the immersion depends on the choice of the user (visual point of view, choice of activities, etc.) and on qualities and potentialities of Second Life (technical architecture, world map, shape of the built environment, etc.).Appropriation and attachment phenomena between actors and locations are described and allow us to observe the formalization of a "home". The various steps of this work contribute to a theory of habitat in virtual worlds

A novel, interactive Android app has been developed that monitors the health of type 2 diabetic patients in real-time, providing patients and their physicians with real-time feedback on all relevant parameters of diabetes. The app includes modules for recording carbohydrate intake and blood glucose; for reminding patients about the need to take medications on schedule; and for tracking physical activity, using movement data via Bluetooth from a pair of wearable insole devices. Two machine learning models were developed to detect seven physical activities: sitting, standing, walking, running, stair ascent, stair descent and use of elliptical trainers. The SVM and decision tree models produced an average accuracy of 85% for these seven activities. The decision tree model is implemented in an app that classifies human activity in real-time.

We are facing a climate crisis, and the world needs to generate electricity in more climate neutral ways. One alternative is to use solar energy. The highest efficiency can be achieved if the surface normal is pointed towards the sun, instead of just having it stationary. To solve this, people make a system called a solar tracker. In this project a prototype of a solar tracker is made, which can follow the sun in any direction. The solar tracker consists of a mechanical structure, two DC-motors that move the structure, and a microcontroller that implements the regulator to control the motors. All the mechanical parts were constructed and then printed using a 3D-printer. Manual control was implemented for making troubleshooting and testing easier. The electrical system is soldered on an experimental board and then mounted with the motor driver and mechanical construction on a bottom structure. There are a few interesting things that could be further developed. One is to implement sensors at the start point and end point of the sun tracking so that the tracker can return to the starting point after the sunset. It would be interesting to scale up the construction a bit and make some more useful measurements on larger panels to see if the system is energy effective enough to be useful; to make some outdoor tests and see how the sensors and control system work in a real-world environment; and to investigate and eventually develop its ability to adapt to cloudy weather.

The concept of emotion and how to regulate it is a central aspect of modern psychology. Within the process model of emotion regulation (Gross, 1998), one issue is how attentional deployment affects emotion regulation and how this can be measured. In task 1, pictures of positive or negative valence were showed in two conditions, either attend or decrease emotional reaction, while participants’ eye movements were followed with an eye tracker. Ratings of arousal and valence were significantly affected by instruction, but dwell times were only significant for positive pictures. In task 2, participants were directed either to emotional or non-emotional parts of emotional pictures while skin conductance was recorded. Arousal and valence ratings decreased significantly in non-emotional areas, but no effect could be found for skin conductance data. Results were generally weak in regards to the effectiveness of measuring gaze to indicate emotion regulation in the form of attentional deployment. For future studies, research of individual differences in habitual usage of attentional deployment for emotion regulation was suggested.

The objective of this research is to study different novel developed techniques for spacecraft attitude determination methods using star tracker sensors. This dissertation addresses various issues on developing improved star tracker software, presents new approaches for better performance of star trackers, and considers applications to realize high precision attitude estimates. Star-sensors are often included in a spacecraft attitude-system instrument suite, where high accuracy pointing capability is required. Novel methods for image processing, camera parameters ground calibration, autonomous star pattern recognition, and recursive star identification are researched and implemented to achieve high accuracy and a high frame rate star tracker that can be used for many space missions. This dissertation presents the methods and algorithms implemented for the one Field of View 'FOV' StarNavI sensor that was tested aboard the STS-107 mission in spring 2003 and the two fields of view StarNavII sensor for the EO-3 spacecraft scheduled for launch in 2007. The results of this research enable advances in spacecraft attitude determination based upon real time star sensing and pattern recognition. Building upon recent developments in image processing, pattern recognition algorithms, focal plane detectors, electro-optics, and microprocessors, the star tracker concept utilized in this research has the following key objectives for spacecraft of the future: lower cost, lower mass and smaller volume, increased robustness to environment-induced aging and instrument response variations, increased adaptability and autonomy via recursive self-calibration and health-monitoring on-orbit. Many of these attributes are consequences of improved algorithms that are derived in this dissertation.

Senare forskning har börjat jämföra etablerade principer inom filmklippning med rön från kognitionsforskning. Ny teknik gör det möjligt att på ett adekvatare sätt ta del av åskådarens upplevelse och interaktion med rörlig bildmedia. Tidigare studier som tas upp i texten har varit inriktade på visuella aspekter, hur brott mot videoredigerings- principer påverkar åskådarens ögonrörelser. Då film och video är ett audiovisuellt medium är det angeläget att undersöka hur ljud påverkar vår visuella bearbetning. Uppsatsens ansats är att undersöka hur varierad synkronisering mellan ljud och bild påverkar och förändrar uppmärksamheten hos åskådare av rörlig bildmedia. Två stimulifilmer har satts samman, en Onbeat version där klipp-punkter i videomaterialet och musikens taktslag ligger i synk, och en Offbeat version där klipp-punkter i videomaterialet ligger fem bildrutor efter musikens taktslag. Som underlag för experimentstudien har 15 försöksdeltagare testats i en ögonrörelsestudie. Resultaten visar på signifikanta skillnader mellan de båda stimulifilmerna, där Offbeat versionen genererade fler ögonrörelser hos försöksdeltagarna.

En vista de la nueva generación de colisionadores de alta luminosidad, HL-LHC y ILC, se hace necesaria una investigación más profunda del diseño y de la tecnología de los detectores de radiaciones basados en silicio, al fin de satisfacer las peticiones de los experimentos en maquinas tan sofisticadas. En esta tesis se presentan tecnologías innovadoras de detectores de radiaciones basados en silicio para futuros trazadores. Tres diferentes dispositivos han sido estudiados y diseñados con la ayuda de diferentes herramientas de simulación. Luego, han sido fabricados en la sala blanca del IMB-CNM de Barcelona y caracterizados con diferentes configuraciones experimentales adecuadas para evaluar la calidad de los detectores y la idoneidad de las tecnologías utilizadas en sus procesos de fabricación. La primera tecnología fue desarrollada con la intención de mejorar los sensores dedicados a sistemas de alineamiento láser en futuros detectores de trazas. El diseño y la tecnología de los detectores de micropistas de una cara p+-in-n, ha sido ligeramente modificada al fin de aumentar la transmitancia de luz Infra-Roja. El diseño de los sensores se ha basado en simulaciones ópticas y el proceso de fabricación ha sido monitoreado consiguiendo una transmitancia del 50% con un paso entre las pistas de 50μm. El segundo dispositivo es un nuevo detector de una cara sensible a la posición en dos dimensiones, basado en tecnología estándar de detectores de silicio de micropistas en los cuales se han generado electrodos resistivos de silicio policristalino acoplados en AC con los implantes. El método de división de carga por resistencias se aplicó leyendo los electrodos resistivos por los dos lados y se usó para obtener informacion sobre la coordenada espacial de un evento ionizante a lo largo de las pistas. Los prototipos que se fabricaron fueron caracterizados con un sistema de láser, con lo que se obtuvo una resolución espacial de aproximadamente el 1.1% de la longitud de la pista, por una señal equivalente a 6 MIPs. Un modelo del detector basado en el simulador Spice se ha desarrollado y comprobado con los datos experimentales, resultando una buena herramienta para la mejora de futuros protipos. Al final, la última propuesta consiste en el nuevo diseño, fabricación y una primera investigación de detectores stripixel 3D. El dispositivo está compuesto de electrodos con forma de columna (ambos los tipo n+ y p+) distribuidos en una cara del substrato según una configuración romboidal. Estos electrodos están conectados entre ellos por medio de dos grupos de pistas metálicas perpendiculares definidas en dos capas de metal separadas que permiten leer las coordenadas X-Y de eventos ionizantes. El diseño del dispositivo ha sido mejorado gracias a simulaciones realizadas con TCAD Sentaurus y la posibilidad de detectar dos dimensiones de un evento de ionización se ha demostrado reconstruyendo la posición de un haz láser dentro de un píxel, definido por dos pistas de tipo p+ consecutivas cruzadas con dos pistas de tipo n+. De las medidas se ha obtenido una resolución espacial de 23 μm. Todos los estudios preliminares, los métodos de fabricación y de caracterización se presentan en los capítulos de esta tesis juntos con los resultados experimentales. / In view of the new generation of high luminosity colliders, HL-LHC and ILC, a farther investigation of silicon radiation detectors design and technology is demanded, in order to satisfy the stringent requirements of the experiments at such sophisticated machines. In this thesis, innovative technologies of silicon radiation detectors for future tracking system are proposed. Three different devices have been studied and designed with the help of different tools for computer simulations. They have been manufactured in the IMB-CNM clean room facilities in Barcelona and characterized with proper experimental setups in order to test both the detectors capabilities and the quality and suitability of the technologies used for their fabrication process. The first technology deals with the upgrade of dedicated sensors for laser alignment systems in future tracker detectors. The design and technology of common single-sided silicon microstrip detectors have been slightly modified in order to improve IR light transmittance of the devices. The layout of the sensors has been decided following the hints of optical simulations and the fabrication process has been properly monitored, obtaining a final transmittance of 50% with a baseline pitch of 50μm. The second device is a novel 2D position sensitive detector based on the standard technology of single-sided AC coupled, silicon microstrip detectors in which resistive coupling electrodes made of polysilicon have been integrated. The resistive charge division method, applied reading out the resistive electrodes at both ends, was used to obtain spatial information on the coordinate of an ionizing event along the strip length. The prototypes fabricated, characterized with a laser setup, showed a longitudinal spatial resolution of about 1.1% of the total strip length (20 mm) for a 6MIPs signal. A Spice-like model of the detector has been developed and crosscheck with the experimental results, providing a good simulation tool for future prototypes optimization. Finally, the last proposal deals with the new design, fabrication and first characterization of double columns stripixel detectors. The device consists of double-column electrodes (both n+ and p+) arranged in a diamond configuration on one side of the n-type silicon bulk and connected by two sets of perpendicular strips organized in two separated metal layers, that allow a X-Y projective readout of the sensor. The design has been optimized with the use of TCAD Sentaurus simulations and 2D position sensitivity has been demonstrated reconstructing a laser beam position within two consecutive p+-type strips crossing two consecutive n+-type strips, with a spatial resolution of 23 μm. The preliminary studies, the fabrication and characterization methods along with the experimental results are presented and discussed in the dedicated chapters of this thesis.

For assembly of product machine is necessary to evaluate a geometric accuracy of individual functional parts of the machine. This process is very demanding and time consuming. One of the reasons of mentioned problems is the lack of software (adaptation) for measuring of the accuracy of geometrical precision. This theses (diploma work) focuses at facilitating the development and creation of own application based on customer requirements and for measuring geometric accuracy with the Laser Tracker AT901 from Leica company. The aim is to create a basic application suitable for measurement of geometric accuracy, which would speed up this process, would be user-friendly, simple and open for further expansion.