The aim of this Master's Thesis was to develop a naturally controllable BCI that can predict motion trajectories from the imagination of motor execution. The approach to reach this aim was to nd a correlation between movement and brain data, which can subsequently be used for the prediction of movement trajectories only by brain signals. To nd this correlation, an experiment was carried out, in which a participant had to do triggered movements with its right arm to four di erent targets. During the execution of the movements, the kinematic and EEG data of the participant were recorded. After a preprocessing stage, the velocity of the kinematic data in x and y directions, and the band power of the EEG data in di erent frequency ranges were calculated and used as features for the calculation of the correlation by a multiple linear regression. When applying the resulting regression parameter to predict trajectories from EEG signals, the best accuracies were shown in the mu and low beta frequency range, as expected. However, the accuracies were not as high as necessary for control of an application. / El objetivo de esta Tesis de Maestría fue desarrollar un interfaz cerebro computador controlable naturalmente que pueda predecir trayectorias de movimiento imaginadas. El enfoque para alcanzar este objetivo fue encontrar una correlación entre el movimiento y los datos cerebrales que puedan ser utilizados posteriormente para la predicción de las trayectorias de movimiento sólo por medio de señales cerebrales. Para encontrar esta correlación, se realizó un experimento, en cual un participante tuvo que realizar movimientos desencadenados con su brazo derecho a cuatro puntos diferentes. Durante el examen de los movimientos, se registraron los datos cinemáticos y de EEG del participante. Después de una etapa de pre-procesamiento, se calcularon las velocidades en las direcciones x y y, de los datos cinemáticos, y la potencia de la banda, de los datos EEG en diferentes rangos de frecuencia, y se utilizaron como características para el cálculo de la correlación mediante con una regresión lineal múltiple. Al aplicar el parámetro de regresión resultante para predecir trayectorias a partir de señales de EEG, las mejores precisiones estuvieron en el rango de frecuencia mu e inferior en beta, como se esperaba. Sin embargo, los resultados no fueron suficientemente precisos como para usarlas para el control de una aplicación. / Tesis

Les phénomènes électrochimiques sont de plus en plus présents dans notre vie quotidienne : ils sont au cœur des batteries de nos ordinateurs, de nos téléphones, dans les piles (à combustibles), etc ... L'objectif de cette thèse est de mieux comprendre les interfaces métal-solvant qui interviennent aux niveaux de ces systèmes (pile à combustible, batteries Li-ion …). Cependant si ceux-ci sont fortement étudiés expérimentalement à la fois dans les laboratoires universitaires et industriels, leur compréhension à l'échelle atomique reste encore imparfaite. Le but de cette thèse est donc d'améliorer la compréhension de l'interface entre l'électrolyte et l'électrode ainsi que sa modification avec le potentiel appliqué à l‘aide de calculs ab initio basés sur la théorie de la fonctionnelle de la densité (DFT). Pour cela au moyen de méthodes de simulation électrochimiques utilisant des approches théoriques spécifiques des surfaces et interfaces développées au sein du laboratoire, nous nous sommes d'abord intéressés à une interface Ruthénium-eau. Le ruthénium est un métal qui crée des interactions fortes avec l'eau : l'eau se trouve alors non dissociée ou partiellement dissociée sur cette surface selon les conditions d'étude. Ainsi, en partant des contradictions apparentes entre résultats expérimentaux présents dans la littérature, nous avons étudiés plus d'une dizaine de phase d'eau sur le ruthénium, dont nous avons extrait le diagramme de phase en fonction du potentiel, de la température, et en tenant compte du fort effet isotopique présent dans ces systèmes. La comparaison de nos résultats calculés avec les résultats expérimentaux nous a permis de rationaliser les observations et d'apporter des réponses sur la cause de l'effet isotopique géant associé à la dissociation de l'eau sur le ruthénium.Dans un second temps nous nous sommes intéressés à une interface lithium-solvant (éthylène carbonate) présente dans les batteries Li-métal. Contrairement à l'étude de l'interface métal-eau précédente nous nous sommes intéressés à la modélisation de la surface et de l'électrolyte liquide. La modélisation du solvant liquide étant plus complexe que celle d'une monocouche d'eau solide adsorbée sur la surface, nous avons donc utilisé une méthode de solvatation implicite que nous avons dû adapter à nos calculs électrochimiques. Nous avons aussi modélisé des molécules de solvant de façon explicite pour pallier aux limites du modèle implicite et inclure les effets de première sphère de solvatation. Notre modèle de solvatation mixte implicite/explicite nous a permis d'étudier les processus électrochimique de réorganisation de surface, de réduction de Li+ ainsi que l'hystérésis/nucléation de surface de Li. / The electrochemical phenomena are increasingly present in our daily lives: they are at the heart of the batteries of our computers, our phones, in batteries (fuels), etc ... The objective of this thesis is to better understand metal-solvent interfaces involved levels of these systems (fuel cell, Li-ion batteries ...). However if they are heavily studied experimentally both in academic and industrial laboratories, understanding at the atomic scale is still imperfect. The aim of this thesis is to improve understanding of the interface between the electrolyte and the electrode and its modification with the potential applied using ab initio calculations based on the Density Functional Theory (DFT).For this simulation using electrochemical methods using specific theoretical approaches of developed surfaces and interfaces in the laboratory, we primarily interested in a ruthenium-water interface. Ruthenium is a metal that creates strong interactions with water: water is then undissociated or partially dissociated on this surface under the conditions of study. Thus, starting from the apparent contradictions between experimental results present in the literature, we have studied more than a dozen water phase on ruthenium, we extract the phase diagram based on potential, temperature, and taking into account the strong isotope effect present in these systems. Comparison of our calculated results with the experimental results allowed us to rationalize the observations and provide answers on the cause of the giant isotope effect associated with the dissociation of water on ruthenium.In a second step we are interested in a lithium-solvent interface (ethylene carbonate) present in the Li-metal batteries. Unlike the previous study of metal-water interface we are interested in modeling the surface and the liquid electrolyte. The modeling of the liquid solvent is more complex than a single layer of solid water adsorbed on the surface, so we used a method of implicit solvation that we had to adapt our electrochemical calculations. We also modeled explicitly solvent molecules to overcome the limitations of the implicit model and include the effects of the first solvation sphere. Our model of mixed implicit solvation / explicitly allowed us to study the electrochemical surface reorganization process, Li + reduction as well as hysteresis / Li surface nucleation.

No description available.

Ce travail de thèse porte sur deux parties relativement distinctes de problématiques liées à l'optimisation de forme. Dans la première moitié de cette thèse, nous développons une librairie permettant la modélisation et l'optimisation de problèmes issus du calcul des variations. Nous illustrons l'efficacité de cet outil en l'appliquant à des exemples variés : le contrôle optimal, le problème de Steiner, le problème des surfaces minimales et enfin la régularisation de contours discrets par minimisation de l'énergie de Willmore. Dans une deuxième partie nous nous intéressons à la mise en œuvre d'un processus de génération aléatoire d'objets de largeur constante en dimension quelconque. La motivation d'un tel travail repose sur la conjecture de Meissner qui est un problème de géométrie convexe ouvert depuis le début du siècle dernier. / This thesis is dedicated to the regularization of discrete images by the minimization of second order energies. More precisely, assuming that the original image is a digital picture of a smooth object, we propose to reconstruct its boundary by the minimization of Willmore's energy under suitable constraints given by the image.Our objective in the present work is to extend their approach in three different directions:• the efficient reconstruction of 3D objects,• the reconstruction of cartoons images,• none smooth objects, sharp edges.

The aim of this Master's Thesis was to develop a naturally controllable BCI that can predict motion trajectories from the imagination of motor execution. The approach to reach this aim was to nd a correlation between movement and brain data, which can subsequently be used for the prediction of movement trajectories only by brain signals. To nd this correlation, an experiment was carried out, in which a participant had to do triggered movements with its right arm to four di erent targets. During the execution of the movements, the kinematic and EEG data of the participant were recorded. After a preprocessing stage, the velocity of the kinematic data in x and y directions, and the band power of the EEG data in di erent frequency ranges were calculated and used as features for the calculation of the correlation by a multiple linear regression. When applying the resulting regression parameter to predict trajectories from EEG signals, the best accuracies were shown in the mu and low beta frequency range, as expected. However, the accuracies were not as high as necessary for control of an application. / El objetivo de esta Tesis de Maestría fue desarrollar un interfaz cerebro computador controlable naturalmente que pueda predecir trayectorias de movimiento imaginadas. El enfoque para alcanzar este objetivo fue encontrar una correlación entre el movimiento y los datos cerebrales que puedan ser utilizados posteriormente para la predicción de las trayectorias de movimiento sólo por medio de señales cerebrales. Para encontrar esta correlación, se realizó un experimento, en cual un participante tuvo que realizar movimientos desencadenados con su brazo derecho a cuatro puntos diferentes. Durante el examen de los movimientos, se registraron los datos cinemáticos y de EEG del participante. Después de una etapa de pre-procesamiento, se calcularon las velocidades en las direcciones x y y, de los datos cinemáticos, y la potencia de la banda, de los datos EEG en diferentes rangos de frecuencia, y se utilizaron como características para el cálculo de la correlación mediante con una regresión lineal múltiple. Al aplicar el parámetro de regresión resultante para predecir trayectorias a partir de señales de EEG, las mejores precisiones estuvieron en el rango de frecuencia mu e inferior en beta, como se esperaba. Sin embargo, los resultados no fueron suficientemente precisos como para usarlas para el control de una aplicación. / Tesis

abstract: The burden of adaptation has been a major limiting factor in the adoption rates of new wearable assistive technologies. This burden has created a necessity for the exploration and combination of two key concepts in the development of upcoming wearables: anticipation and invisibility. The combination of these two topics has created the field of Anticipatory and Invisible Interfaces (AII) In this dissertation, a novel framework is introduced for the development of anticipatory devices that augment the proprioceptive system in individuals with neurodegenerative disorders in a seamless way that scaffolds off of existing cognitive feedback models. The framework suggests three main categories of consideration in the development of devices which are anticipatory and invisible: • Idiosyncratic Design: How do can a design encapsulate the unique characteristics of the individual in the design of assistive aids? • Adaptation to Intrapersonal Variations: As individuals progress through the various stages of a disability/neurological disorder, how can the technology adapt thresholds for feedback over time to address these shifts in ability? • Context Aware Invisibility: How can the mechanisms of interaction be modified in order to reduce cognitive load? The concepts proposed in this framework can be generalized to a broad range of domains; however, there are two primary applications for this work: rehabilitation and assistive aids. In preliminary studies, the framework is applied in the areas of Parkinsonian freezing of gait anticipation and the anticipation of body non-compliance during rehabilitative exercise. / Dissertation/Thesis / Doctoral Dissertation Computer Science 2020

International Telemetering Conference Proceedings / October 25-28, 1993 / Riviera Hotel and Convention Center, Las Vegas, Nevada / With the ever increasing need for faster data rates and the emergence of faster network interfaces such as Fiber Distributed Data Interface (FDDI), the task of adding new network interfaces to a telemetry system and supporting existing ones is becoming increasingly more complex. This complexity can be eliminated if the data acquisition hardware and software allows new network interfaces to be easily integrated into a telemetry system. It is the purpose of this paper to address the issues involved when dealing with multiple, heterogeneous, networking environments in telemetry systems. The paper will show how the use of flexible telemetry hardware and software will simplify the integration of new networks into an existing system, and how this flexibility can allow data acquisition applications to take advantage of a heterogeneous network.

<p>This Licentiate thesis summarizes the work carried out by the author the years 2004 to 2008 at the University of Iceland and the Royal Institute of Technology (KTH) in Sweden. The aim of the project was to investigate the structure of sapphire (alpha-Al2O3) surfaces, both for pure scientific reasons and also for potential use as substrate for GaN-growth by molecular beam epitaxy.</p><p>More generally the thesis describes some surface science methods used for investigating the substrates; the general physical back ground, the experi- mental implementation and what information they can give. The described techniques are used for surface analysis on sapphire substrates which have been treated variously in order to optimize them for use as templates for epi- taxial growth of GaN or related III-V compounds.</p><p>The thesis is based on three published papers.</p><p>The first paper focuses on the formation a thin AlN layer on sapphire, which may act as a buffer layer for potential epitaxial growth of GaN or any related III-V materials. Two types of sapphire substrates (reconstructed and non- reconstructed) were exposed to ammonia resulting in the formation of AlN on the surface. The efficiency of the AlN formation (nitridation efficiency) for the two surfaces was then compared as a function of substrate temperature through photoelectron spectroscopy and low electron energy diffraction. The reconstructed surface showed a much higher nitridation efficiency than the non-reconstructed surface.</p><p>In the second paper, the affect of different annealing processes on the sapphire morphology, and thus its capability to act as a template for GaN growth, was studied. Atomic force microscopy, X-ray diffraction analysis together with ellipsometry measurements showed that annealing in H2 ambient and subse- quent annealing at 1300 °C in O2 for 11 hours resulted in high quality and atomically flat sapphire surface suitable for III-V epitaxial growth.</p><p>The third paper describes the effect of argon sputtering on cleaning GaN surfaces and the possibility of using indium as surfactant for establishing a clean and stoichiometric GaN surface, after such sputtering. Soft sputtering, followed by deposition of 2 ML of indium and subsequent annealing at around 500 °C resulted in a well ordered and clean GaN surface while hard sputtering introduced defects and incorporated both metallic gallium and indium in the surface.</p>

No description available.

No description available.