964 resultados para Compliant building blocks


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Nesta dissertação apresentamos um trabalho de desenvolvimento e utilização de pulsos de radiofreqüência modulados simultaneamente em freqüência, amplitude e fase (pulsos fortemente modulados, SMP, do inglês Strongly Modulated Pulses) para criar estados iniciais e executar operações unitárias que servem como blocos básicos para processamento da informação quântica utilizando Ressonância Magnética Nuclear (RMN). As implementações experimentais foram realizas em um sistema de 3 q-bits constituído por spins nucleares de Césio 133 (spin nuclear 7/2) em uma amostra de cristal líquido em fase nemática. Os pulsos SMP´s foram construídos teoricamente utilizando um programa especialmente desenvolvido para esse fim, sendo o mesmo baseado no processo de otimização numérica Simplex Nelder-Mead. Através deste programa, os pulsos SMP foram otimizados de modo a executarem as operações lógicas desejadas com durações consideravelmente menores que aquelas realizadas usando o procedimento usual de RMN, ou seja, seqüências de pulsos e evoluções livres. Isso tem a vantagem de reduzir os efeitos de descoerência decorrentes da relaxação do sistema. Os conceitos teóricos envolvidos na criação dos SMPs são apresentados e as principais dificuldades (experimentais e teóricas) que podem surgir devido ao uso desses procedimentos são discutidas. Como exemplos de aplicação, foram produzidos os estados pseudo-puros usados como estados iniciais de operações lógicas em RMN, bem como operações lógicas que foram posteriormente aplicadas aos mesmos. Utilizando os SMP\'s também foi possível realizar experimentalmente os algoritmos quânticos de Grover e Deutsch-Jozsa para 3 q-bits. A fidelidade das implementações experimentais foi determinadas utilizando as matrizes densidade experimentais obtidas utilizando um método de tomografia da matriz densidade previamente desenvolvido.

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Acquiring 3D shape from images is a classic problem in Computer Vision occupying researchers for at least 20 years. Only recently however have these ideas matured enough to provide highly accurate results. We present a complete algorithm to reconstruct 3D objects from images using the stereo correspondence cue. The technique can be described as a pipeline of four basic building blocks: camera calibration, image segmentation, photo-consistency estimation from images, and surface extraction from photo-consistency. In this Chapter we will put more emphasis on the latter two: namely how to extract geometric information from a set of photographs without explicit camera visibility, and how to combine different geometry estimates in an optimal way. © 2010 Springer-Verlag Berlin Heidelberg.

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© 2016 Springer Science+Business Media DordrechtG2-Monopoles are solutions to gauge theoretical equations on G2-manifolds. If the G2-manifolds under consideration are compact, then any irreducible G2-monopole must have singularities. It is then important to understand which kind of singularities G2-monopoles can have. We give examples (in the noncompact case) of non-Abelian monopoles with Dirac type singularities, and examples of monopoles whose singularities are not of that type. We also give an existence result for Abelian monopoles with Dirac type singularities on compact manifolds. This should be one of the building blocks in a gluing construction aimed at constructing non-Abelian ones.

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This chapter examines the personal and contextual factors of youth sport that affect sport expertise and developmental outcomes. The developmental model of sport participation (DMSP) is used as a comprehensive framework that outlines different pathways of involvement in sport. Activities and contexts that promote continued sport participation and expert performance are discussed as the building blocks of all effective youth sport programs. This chapter provides evidence that performance in sport, participation, and psychological development should be considered as a whole instead of as separate entities by youth sport programmers. Adults in youth sports (i.e. coaches, parents, sport psychologists, administrators) must consider the differing implications of concepts such as deliberate play, deliberate practice, sampling, specialization, and program structure at different stages of an athlete's talent development. Seven postulates are presented regarding important transitions in youth sport and the role that sampling and deliberate play, as opposed to specialization and deliberate practice, can have during the childhood in promoting continued participation and elite performance in sport

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Collecting data via a questionnaire and analyzing them while preserving respondents’ privacy may increase the number of respondents and the truthfulness of their responses. It may also reduce the systematic differences between respondents and non-respondents. In this paper, we propose a privacy-preserving method for collecting and analyzing survey responses using secure multi-party computation (SMC). The method is secure under the semi-honest adversarial model. The proposed method computes a wide variety of statistics. Total and stratified statistical counts are computed using the secure protocols developed in this paper. Then, additional statistics, such as a contingency table, a chi-square test, an odds ratio, and logistic regression, are computed within the R statistical environment using the statistical counts as building blocks. The method was evaluated on a questionnaire dataset of 3,158 respondents sampled for a medical study and simulated questionnaire datasets of up to 50,000 respondents. The computation time for the statistical analyses linearly scales as the number of respondents increases. The results show that the method is efficient and scalable for practical use. It can also be used for other applications in which categorical data are collected.

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The RAGE Exploitation Plan is a living document, to be upgraded along the project lifecycle, supporting RAGE partners in defining how the results of the RAGE RIA will be used both in commercial and non-comercial settings. The Exploitation Plan covers the entire process from the definition of the business case for the RAGE Ecosystem to the creation of the sustainability conditions for its real-world operation beyond the H2020 project co-funding period. The Exploitation Plan will be published in three incremental versions, due at months 18, 36 and 42 of the project lifetime. This early stage version 1 of 3 is mainly devoted to: i. Setting-up the structure and the initial building blocks to be populated and completed in the future editions of the Exploitation Plan and to ii. providing additional guidance for market intelligence gathering, business modelling definition and validation, outreach and industry engagement and ultimately providing insights for the development, validation and evaluation of RAGE results across the project´s workplan execution. These tasks will in turn render suitable inputs to enhance the two future editions of the Exploitation Plan.

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Background
It is generally acknowledged that a functional understanding of a biological system can only be obtained by an understanding of the collective of molecular interactions in form of biological networks. Protein networks are one particular network type of special importance, because proteins form the functional base units of every biological cell. On a mesoscopic level of protein networks, modules are of significant importance because these building blocks may be the next elementary functional level above individual proteins allowing to gain insight into fundamental organizational principles of biological cells.
Results
In this paper, we provide a comparative analysis of five popular and four novel module detection algorithms. We study these module prediction methods for simulated benchmark networks as well as 10 biological protein interaction networks (PINs). A particular focus of our analysis is placed on the biological meaning of the predicted modules by utilizing the Gene Ontology (GO) database as gold standard for the definition of biological processes. Furthermore, we investigate the robustness of the results by perturbing the PINs simulating in this way our incomplete knowledge of protein networks.
Conclusions
Overall, our study reveals that there is a large heterogeneity among the different module prediction algorithms if one zooms-in the biological level of biological processes in the form of GO terms and all methods are severely affected by a slight perturbation of the networks. However, we also find pathways that are enriched in multiple modules, which could provide important information about the hierarchical organization of the system

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Green energy and Green technology are the most of the quoted terms in the context of modern science and technology. Technology which is close to nature is the necessity of the modern world which is haunted by global warming and climatic alterations. Proper utilization of solar energy is one of the goals of Green Energy Movement. The present thesis deals with the work carried out in the eld of nanotechnology and its possible use in various applications (employing natural dyes) like solar cells. Unlike arti cial dyes, the natural dyes are available, easy to prepare, low in cost, non-toxic, environmentally friendly and fully biodegradable. Looking to the 21st century, the nano/micro sciences will be a chief contributor to scienti c and technological developments. As nanotechnology progresses and complex nanosystems are fabricated, a growing impetus is being given to the development of multi-functional and size-dependent materials. The control of the morphology, from the nano to the micrometer scales, associated with the incorporation of several functionalities can yield entirely new smart hybrid materials. They are special class of materials which provide a new method for the improvement of the environmental stability of the material with interesting optical properties and opening a land of opportunities for applications in the eld of photonics. Zinc oxide (ZnO) is one such multipurpose material that has been explored for applications in sensing, environmental monitoring, and bio-medical systems and communications technology. Understanding the growth mechanism and tailoring their morphology is essential for the use of ZnO crystals as nano/micro electromechanical systems and also as building blocks of other nanosystems.

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Les sulfilimines et les sulfoximines sont des motifs structuraux dont l’intérêt synthétique est grandissant, notamment du fait de leurs applications en chimie médicinale et en agrochimie. Les travaux rapportés dans cet ouvrage décrivent le développement de nouvelles méthodes de synthèse efficaces pour la production de ces unités atypiques. Ces méthodes sont basées sur la réactivité d’une source d’azote électrophile, vis-à-vis de thioéthers et de sulfoxydes. L’utilisation d’un complexe métallique introduit en quantité catalytique a permis de favoriser le processus réactionnel. En tirant bénéfice de l’expertise de notre groupe de recherche sur le développement de réactions d’amination stéréosélectives de liaisons C-H et d’aziridination de styrènes, nous avons d’abord étudié la réactivité des N-mésyloxycarbamates comme source d’azote électrophile. Après avoir optimisé sa synthèse sur grande échelle, ce réactif chiral a été utilisé dans des réactions d’amination de thioéthers et de sulfoxydes, catalysées par un dimère de rhodium (II) chiral. Un processus diastéréosélectif efficace a été mis au point, permettant de produire des sulfilimines et des sulfoximines chirales avec d’excellents rendements et sélectivités. Au cours de l’optimisation de cette méthode de synthèse, nous avons pu constater l’effet déterminant de certains additifs sur la réactivité et la sélectivité de la réaction. Une étude mécanistique a été entreprise afin de comprendre leur mode d’action. Il a été observé qu’une base de Lewis telle que le 4-diméthylaminopyridine (DMAP) pouvait se coordiner au dimère de rhodium(II) et modifier ses propriétés structurales et redox. Les résultats que nous avons obtenus suggèrent que l’espèce catalytique active est un dimère de rhodium de valence mixte Rh(II)/Rh(III). Nous avons également découvert que l’incorporation de sels de bispyridinium avait une influence cruciale sur la diastéréosélectivité de la réaction. D’autres expériences sur la nature du groupe partant du réactif N-sulfonyloxycarbamate nous ont permis de postuler qu’une espèce nitrénoïde de rhodium était l’intermédiaire clé du processus d’amination. De plus, l’exploitation des techniques de chimie en débit continu nous a permis de développer une méthode d’amination de thioéthers et de sulfoxydes très performante, en utilisant les azotures comme source d’azote électrophile. Basée sur la décompositon photochimique d’azotures en présence d’un complexe de fer (III) simple et commercialement disponible, nous avons été en mesure de produire des sulfilimines et des sulfoximines avec d’excellents rendements. Le temps de résidence du procédé d’amination a pu être sensiblement réduit par la conception d’un nouveau type de réacteur photochimique capillaire. Ces améliorations techniques ont permis de rendre la synthèse plus productive, ce qui constitue un élément important d’un point de vue industriel.

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Les convertisseurs de longueur d’onde sont essentiels pour la réalisation de réseaux de communications optiques à routage en longueur d’onde. Dans la littérature, les convertisseurs de longueur d’onde basés sur le mélange à quatre ondes dans les amplificateurs optiques à semi-conducteur constituent une solution extrêmement intéressante, et ce, en raison de leurs nombreuses caractéristiques nécessaires à l’implémentation de tels réseaux de communications. Avec l’émergence des systèmes commerciaux de détection cohérente, ainsi qu’avec les récentes avancées dans le domaine du traitement de signal numérique, il est impératif d’évaluer la performance des convertisseurs de longueur d’onde, et ce, dans le contexte des formats de modulation avancés. Les objectifs de cette thèse sont : 1) d’étudier la faisabilité des convertisseurs de longueur d’onde basés sur le mélange à quatre ondes dans les amplificateurs optiques à semi-conducteur pour les formats de modulation avancés et 2) de proposer une technique basée sur le traitement de signal numérique afin d’améliorer leur performance. En premier lieu, une étude expérimentale de la conversion de longueur d’onde de formats de modulation d’amplitude en quadrature (quadrature amplitude modulation - QAM) est réalisée. En particulier, la conversion de longueur d’onde de signaux 16-QAM à 16 Gbaud et 64-QAM à 5 Gbaud dans un amplificateur optique à semi-conducteur commercial est réalisée sur toute la bande C. Les résultats démontrent qu’en raison des distorsions non-linéaires induites sur le signal converti, le point d’opération optimal du convertisseur de longueur d’onde est différent de celui obtenu lors de la conversion de longueur d’onde de formats de modulation en intensité. En effet, dans le contexte des formats de modulation avancés, c’est le compromis entre la puissance du signal converti et les non-linéarités induites qui détermine le point d’opération optimal du convertisseur de longueur d’onde. Les récepteurs cohérents permettent l’utilisation de techniques de traitement de signal numérique afin de compenser la détérioration du signal transmis suite à sa détection. Afin de mettre à profit les nouvelles possibilités offertes par le traitement de signal numérique, une technique numérique de post-compensation des distorsions induites sur le signal converti, basée sur une analyse petit-signal des équations gouvernant la dynamique du gain à l’intérieur des amplificateurs optiques à semi-conducteur, est développée. L’efficacité de cette technique est démontrée à l’aide de simulations numériques et de mesures expérimentales de conversion de longueur d’onde de signaux 16-QAM à 10 Gbaud et 64-QAM à 5 Gbaud. Cette méthode permet d’améliorer de façon significative les performances du convertisseur de longueur d’onde, et ce, principalement pour les formats de modulation avancés d’ordre supérieur tel que 64-QAM. Finalement, une étude expérimentale exhaustive de la technique de post-compensation des distorsions induites sur le signal converti est effectuée pour des signaux 64-QAM. Les résultats démontrent que, même en présence d’un signal à bruité à l’entrée du convertisseur de longueur d’onde, la technique proposée améliore toujours la qualité du signal reçu. De plus, une étude du point d’opération optimal du convertisseur de longueur d’onde est effectuée et démontre que celui-ci varie en fonction des pertes optiques suivant la conversion de longueur d’onde. Dans un réseau de communication optique à routage en longueur d’onde, le signal est susceptible de passer par plusieurs étages de conversion de longueur d’onde. Pour cette raison, l’efficacité de la technique de post-compensation est démontrée, et ce pour la première fois dans la littérature, pour deux étages successifs de conversion de longueur d’onde de signaux 64-QAM à 5 Gbaud. Les résultats de cette thèse montrent que les convertisseurs de longueur d’ondes basés sur le mélange à quatre ondes dans les amplificateurs optiques à semi-conducteur, utilisés en conjonction avec des techniques de traitement de signal numérique, constituent une technologie extrêmement prometteuse pour les réseaux de communications optiques modernes à routage en longueur d’onde.

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Hebb proposed that synapses between neurons that fire synchronously are strengthened, forming cell assemblies and phase sequences. The former, on a shorter scale, are ensembles of synchronized cells that function transiently as a closed processing system; the latter, on a larger scale, correspond to the sequential activation of cell assemblies able to represent percepts and behaviors. Nowadays, the recording of large neuronal populations allows for the detection of multiple cell assemblies. Within Hebb's theory, the next logical step is the analysis of phase sequences. Here we detected phase sequences as consecutive assembly activation patterns, and then analyzed their graph attributes in relation to behavior. We investigated action potentials recorded from the adult rat hippocampus and neocortex before, during and after novel object exploration (experimental periods). Within assembly graphs, each assembly corresponded to a node, and each edge corresponded to the temporal sequence of consecutive node activations. The sum of all assembly activations was proportional to firing rates, but the activity of individual assemblies was not. Assembly repertoire was stable across experimental periods, suggesting that novel experience does not create new assemblies in the adult rat. Assembly graph attributes, on the other hand, varied significantly across behavioral states and experimental periods, and were separable enough to correctly classify experimental periods (Naïve Bayes classifier; maximum AUROCs ranging from 0.55 to 0.99) and behavioral states (waking, slow wave sleep, and rapid eye movement sleep; maximum AUROCs ranging from 0.64 to 0.98). Our findings agree with Hebb's view that assemblies correspond to primitive building blocks of representation, nearly unchanged in the adult, while phase sequences are labile across behavioral states and change after novel experience. The results are compatible with a role for phase sequences in behavior and cognition.

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Intramolecular C–H insertion reactions of α-diazocarbonyl compounds typically proceed with preferential five-membered ring formation. However, the presence of a heteroatom such as nitrogen can activate an adjacent C–H site toward insertion resulting in regiocontrol issues. In the case of α-diazoacetamide derivatives, both β- and γ-lactam products are possible owing to this activating effect. Both β- and γ-lactam products are powerful synthetic building blocks in the area of organic synthesis, as well as a common scaffold in a range of natural and pharmaceutical products and therefore C–H insertion reactions to form such compounds are attractive processes.

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This paper is the second in a series of studies working towards constructing a realistic, evolving, non-potential coronal model for the solar magnetic carpet. In the present study, the interaction of two magnetic elements is considered. Our objectives are to study magnetic energy build-up, storage and dissipation as a result of emergence, cancellation, and flyby of these magnetic elements. In the future these interactions will be the basic building blocks of more complicated simulations involving hundreds of elements. Each interaction is simulated in the presence of an overlying uniform magnetic field, which lies at various orientations with respect to the evolving magnetic elements. For these three small-scale interactions, the free energy stored in the field at the end of the simulation ranges from 0.2 – 2.1×1026 ergs, whilst the total energy dissipated ranges from 1.3 – 6.3×1026 ergs. For all cases, a stronger overlying field results in higher energy storage and dissipation. For the cancellation and emergence simulations, motion perpendicular to the overlying field results in the highest values. For the flyby simulations, motion parallel to the overlying field gives the highest values. In all cases, the free energy built up is sufficient to explain small-scale phenomena such as X-ray bright points or nanoflares. In addition, if scaled for the correct number of magnetic elements for the volume considered, the energy continually dissipated provides a significant fraction of the quiet Sun coronal heating budget.

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With the aim of producing materials with enhanced optical and photocatalytic properties, titanate nanotubes (TNTs) modified by cobalt doping (Co-TNT) and by Na+ -> Co ion-exchange (TNT/Co) were successfully prepared by a hydrothermal method. The influence of the doping level and of the cobalt position in the TNT crystalline structure was studied. Although no perceptible influence of the cobalt ion position on the morphology of the prepared titanate nanotubes was observed, the optical behaviour of the cobalt modified samples is clearly dependent on the cobalt ions either substituting the Ti4+ ions in the TiO6 octahedra building blocks of the TNT structure (doped samples) or replacing the Na+ ions between the TiO6 interlayers (ion-exchange samples). The catalytic ability of these materials on pollutant photodegradation was investigated. First, the evaluation of hydroxyl radical formation using the terephthalic acid as a probe was performed. Afterwards, phenol, naphthol yellow S and brilliant green were used as model pollutants. Anticipating real world situations, photocatalytic experiments were performed using solutions combining these pollutants. The results show that the Co modified TNT materials (Co-TNT and TNT/Co) are good catalysts, the photocatalytic performance being dependent on the Co/Ti ratio and on the structural metal location. The Co(1%)-TNT doped sample was the best photocatalyst for all the degradation processes studied.