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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.
61

Um ambiente integrado para apoio ao desenvolvimento distribuído de software

Gärtner, Vilson Cristiano 22 March 2011 (has links)
Submitted by CARLA MARIA GOULART DE MORAES (carlagm) on 2015-04-06T17:18:33Z No. of bitstreams: 1 VilsonGartnerComputacao.pdf: 9068377 bytes, checksum: 6ace07d8901f11d83ef8a8c13f4f62c7 (MD5) / Made available in DSpace on 2015-04-06T17:18:33Z (GMT). No. of bitstreams: 1 VilsonGartnerComputacao.pdf: 9068377 bytes, checksum: 6ace07d8901f11d83ef8a8c13f4f62c7 (MD5) Previous issue date: 2011 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O Desenvolvimento Distribuído de Software (DDS) é um modelo de desenvolvimento que vem se intensificando nos últimos anos. Também conhecido como Desenvolvimento Global de Software (DGS), esse modelo de desenvolvimento é realizado por equipes em diferentes localizações geográficas. Entre os fatores que contribuem para esse aumento, está a necessidade de negócio das corporações, que buscam redução de custos, recursos qualificados e necessidade de uma presença global. Em outros casos, se deve ao surgimento de novos movimentos de desenvolvimento de software, como a comunidade de software livre, um exemplo bem sucedido de DDS. Apesar da necessidade ou mesmo da conveniência de desenvolver o software de forma distribuída, é extremamente difícil fazê-lo com sucesso. A separação física traz uma série de problemas e desafios interessantes que recém estão começando a ser compreendidas: questões estratégicas, questões culturais, comunicação inadequada, gestão do conhecimento, alocação de tarefas, confiança, questões técnicas, entre outros. Desde que surgiu, o DDS mudou grande parte da tradição do desenvolvimento de software e, para manter o seu mercado, as organizações não podem depender das mesmas competências e tecnologias de engenharia de software utilizadas no desenvolvimento interno. Nesse sentido, o presente trabalho tem por objetivo auxiliar na redução dos problemas e dificuldades trazidos por esse modelo de desenvolvimento, através da implementação de um ambiente de desenvolvimento cujas ferramentas foram definidas com base em estudos e trabalhos relacionados ao tema. / The Distributed Software Development (DSD) is a development model that has been intensified in recent years. Also known as Global Software Development (GSD), this development model is done by teams in different geographical locations. Among the factors that have contributed to this increase, there is the corporations business need of seeking ways to reduce costs, seeking skilled resources and having a global presence. In other cases, it is due to the emergence of new movements in software development, such as the free software community, a successful example of DSD. Despite the need or even desirability of developing software in a distributed way, it is extremely difficult to do this successfully. Physical separation has a number of interesting problems and challenges that are just beginning to be understood: strategic issues, cultural issues, inadequate communication, knowledge management, task allocation, trust, technical issues, among others. DSD has changed much of the tradition of software development since it appeared. Organizations cannot rely on the same skills and software engineering technologies used internally to maintain this new market. In this way, this work aims to help to reduce the problems and difficulties brought by this type of development, through the implementation of a software development environment whose tools were defined based on studies related to the topic.
62

R-*, Réflexion au Service de l'Évolution des Systèmes de Systèmes

Labéjof, Jonathan 20 December 2012 (has links) (PDF)
Dans un monde de plus en plus connecté, le besoin d'interconnecter des systèmes hétérogènes apparait de plus en plus présent. Les Systèmes de Systèmes (SoS) sont une approche de supervision et de contrôle global où les systèmes constituants sont caractérisés comme des sous-systèmes du SoS. Certains de ces sous-systèmes peuvent être sujets à un environnement dynamique leur demandant d'évoluer pour répondre à de nouvelles exigences, voire de s'adapter s'ils doivent répondre à un besoin de disponibilité. La principale difficulté dans la gestion des évolutions possibles est qu'elles peuvent impacter plusieurs sous-systèmes connectés, et par extension, une vision globale comme celle proposée par un système de systèmes. Ainsi, les problèmes d'évolution et d'adaptation d'un SoS se posent. Dans un cadre d'ingénierie logicielle, cette thèse propose l'approche R-* qui soutient l'hypothèse que plus un système est Réflexif, et plus il devient capable de s'adapter, et donc d'évoluer. Trois contributions majeures et un cas d'utilisation évalu ́e sont proposés pour justifier l'intérêt de R-*. R-DDS et R-MOM ajoutent la capacité de réflexivité dans des sous-systèmes de communication asynchrones, et R-EMS ajoute la capacité de réflexivité sur la vision globale d'un SoS, incluant ses sous-syst'emes et son environnement. R-DDS ajoute la réflexivité à l'intergiciel de Service de Distribution de Données dédié aux domaines du temps-réel et de l'embarqué. R-MOM remonte en abstraction pour proposer la réflexivité au niveau des fonctionalités d'un intergiciel asynchrone. R-EMS est un système de gestion d'environnement réflexif en support de l'utilisation d'un SoS. Finalement, le cas d'utilisation est une implémentation d'un sous-modèle du système de systèmes TACTICOS de THALES, qui servira également d'environnement d'évaluation.
63

Contribution à la conception de synthèses de fréquence pour liaison satellite embarquée: montée en résolution et réduction de raies parasites

Juyon, Julien 17 December 2013 (has links) (PDF)
Être connecté en haut débit au WEB à bord des avions est un marché à fort potentiel commercial qui a motivé le lancement d'un projet nommé FAST (Fiber-like Aircraft SaTellite communications). Dans le cadre de ce projet, la société Axess Europe, en partenariat avec sept partenaires dont le LAAS-CNRS a développé une antenne plane à matrice d'éléments rayonnants dont l'orientation du faisceau est gérée électroniquement. Cette antenne permet la communication avion-satellite. Cette thèse traite de la partie synthèse de fréquence de l'électronique d'émission-réception de l'antenne. Afin de pouvoir s'adapter à n'importe plan de fréquence de satellite, mais aussi la volonté de pouvoir compenser l'effet Doppler dans une certaine mesure, ces travaux se sont tournés vers l'amélioration de la résolution d'une boucle à verrouillage de phase (PLL), et plus particulièrement sur l'étude et la réalisation d'un diviseur de fréquence fractionnaire capable de satisfaire ces exigences. Dans une PLL, la division fractionnaire permet d'augmenter la résolution fréquentielle sans devoir diminuer la fréquence de référence, ce qui permet de conserver la dynamique de boucle, la bande passante ainsi que les caractéristiques en bruit de phase. Cependant, elle génère des raies parasites gênantes, que l'on peut toutefois atténuer avec plusieurs techniques bien connues. Parmi ces techniques, on trouve le DDS (synthétiseur numérique direct) utilisé comme diviseur fractionnaire, mais il ne permet d'atteindre la résolution fréquentielle souhaitée que pour une taille trop importante. Nous avons donc développé une variante basée sur un DDS qui permet d'en conserver les avantages pour la réduction des raies parasites, tout en augmentant la résolution fréquentielle sans devoir en augmenter la taille. Une étude exhaustive de cette structure originale est proposée.
64

Functionalized Layered Double Hydroxides and Gold Nanorods

Dutta, Dipak January 2011 (has links) (PDF)
The reversible and topotactic insertion of guest species within layered host lattices, known as intercalation is a widely studied phenomena. The Layered Double Hydroxides (LDHs) or Anionic Alloys are important class of layered solids with its own distinct ion-exchange host-Guest Chemistry. The LDH structure may be derived from that of Brucite, Mg(OH)2, by random isomorphous substitution of Mg2+ ions by trivalent cations like Al3+, Ga3+ etc. This substitution leaves an excess positive charge on the layers, which is compensated by interlamellar anions. These ions are exchangeable and thus new functionalities can be introduced to ion exchange reactions. Insertion of neutral, non-polar or poorly water-soluble guest molecules remains a challenge. In the present study, two methodologies were adopted to extend the host-guest chemistry of LDHs to neutral and non-polar species, first by using Hydrophobic interaction and second, charge transfer (CT) interaction as driving force. Hlydrophobic interaction as driving force involves functionalization of the Mg-Al-LDH galleries as bilayers, thus covering the essentially hydrophilic interlamellar space of the LDH to one that is hydrophobic and able to solubilize neutral molecules like Anthracene. CT interaction as driving force, involves pre-functionalization of the galleries of the LDH with a donor species e.g. 4-aminobenzoic acid by conventional ion exchange methods to form a LDH-donor intercalated compound. This compound can selectively adsorb acceptor species like Chloranil, Tetracyanoquinodimethane etc. into the interlamellar space of the solid by forming donor-acceptor complexes. The confined donor-acceptor complexes have been characterized by X-Ray Diffraction, UV-Visible, Fourier Transformed Infra-Red and Raman Spectroscopy, Molecular Dynamics Simulations were able to reproduce the experimental results. One dimensional gold nanostructure like nanorods (AuNRs) have received great attention due to their size dependent optical properties, Extending these applications requires assembling the AuNRs into one-, two- and if possible three-dimensional architectures. Several approaches have been developed to assemble AuNRs in two-orientation modes namely end-to-end and side-to-side. The present study self-assembly of the AuNRs has been achieved by anchoring β-cyclodextrin (β-CD) cavities to the nanorods surface. The host-guest chemistry of β-CD has been exploited to assemble the AuNRs. Our strategy was to use a guest molecule that is capable to link β-CD into 1:2 host-guest fashions to link up two β-CD capped nanorods. The guest molecule chosen for the present study was 1,10-phenanthroline. Linkage between the ends of rods leading to V-shaped rods dimmer assembly and side-to-side assembly was achieved by varying the extent of cyclodextrin capping of the AuNRs followed by the addition of linker, 1,10-phenanthroline. The formation of the assembly was characterized using UV-Visible-Near-IR Spectoscopy and Transmission Electron Microscopy.
65

Řídicí mikroprocesorový systém s kmitočtovým syntezátorem pro KV radiostanici / Microprocessor control unit with frequency synthesizer for SW radiostation

Povalač, Aleš January 2009 (has links)
The thesis is focused on the development of a radioamateur short-wave transceiver. The basic functions, features and parameters are described in the introduction. The bandplan and appropriate types of emission are also included in the introductory part. The frequency synthesis module is discussed in the second part of the document. Emphasis is placed on the direct digital synthesis method (DDS) using modern Analog Devices circuits. The proposed DDS module includes a high-speed clock source. The description of an intermediate frequency module with a demodulator is also placed there. The final part in devoted to the design of a transceiver control panel with a graphical display, a keyboard and a rotary encoder. The firmware for an ATmega128 microcontroller is described in detail at the end of the thesis.
66

Vysokofrekvenční obvodový analyzátor s DDS / DDS Based High-frequency circuit analyzer

Priškin, Jiří January 2010 (has links)
At first this thesis is dealing with the basic principles of network analyzers and afterwards goes to propose conception of a polyscope, as a special type of the scalar network analyzer, designed for magnitude frequency response measurement of two-port devices. As a result of this part of the thesis is the polyscope's block circuit diagram and also selection of key integrated circuits for sweep generator, logarithmic detector and control circuits. As the following part of the thesis is a design of the all basic analyzer's circuits resulting in their schematics diagrams and printed circuit boards, do assembly of all modules and mechanical construction of the instrument and look of the front panel. Some of the tasks is implementation of the firmware and personal computer application able to download measured data from the circuit analyzer via USB and generate chart in Microsoft Office Excel book.
67

Magnetoterapeutický přístroj pro léčbu dětské mozkové obrny / Magnetotherapeutic device for Child Neurology

Walek, Petr January 2010 (has links)
Project Magnetotherapeutic device for Child Neurology in his forepart paies medical use of Pulsatile Magnetic Field. Summaries a therapeutic effects of field which is interacting with biotic issue and determines which of those effects are acceptable for treatment of Infantile Paralysis. Below it describes single Bio-Parametres of Pulsatile Magnetic Field and analyses reasons and effects of Infantile Paralysis. In second part is described a block diagram of magnetotherapeutic device for treatment of Infantile Paralysis. Described is principle of function of blocks. In third part is defined circuit solving of controlling, supervisory and generating part of magnetotherapeutic device. Function and wiring of components is described in detail. There is also created a Printed Circuit Board. Device is controlled by three microcontrollers, therefore there are described flowcharts and controlling programs for microcontrollers.
68

Kmitočtové syntezátory / Frequency Synthesizers

Lapčík, Josef January 2011 (has links)
This diploma thesis concerns with analysis and dividing of frequency synthesizers and design of DDS, PLL synthesizers. Base types of frequency synthesizers are described including differences between methods of their operation. Base circuits of both – DDS and PLL synthesizers and other important circuits are described in details at design part of this thesis. Design of DDS and PLL synthesizer is described in particular sections. Both synthesizers are directly realized and stand-alone control applications are created. PLL synthesizer is also ready to control thru Agilent VEE program environment. Particular example application is designed in Agilent VEE. This application is used as basis of attached lab project.
69

Propuesta de arquitectura distribuida de control inteligente basada en políticas de calidad de servicio

Poza Luján, José Luis 10 February 2012 (has links)
La tesis se enmarca en el estudio de las arquitecturas inteligentes de control distribuido y de los sistemas de comunicaciones empleados, más concretamente el trabajo se centra en la optimización del sistema de control por medio de la evaluación del rendimiento en el middleware a través de los parámetros de calidad de servicio y de la optimización del control empleando políticas de calidad de servicio. El principal objetivo de este trabajo ha sido estudiar, diseñar, desarrollar y evaluar una arquitectura de control distribuido, basándose en el estándar de comunicaciones Data-Distribution Service for Real-Time Systems (DDS) propuesto por la organización Object Management Group (OMG). Como aportación principal de la tesis se propone el diseño de una arquitectura distribuida de control inteligente que de soporte a la QoS, tanto en la medición por medio de los parámetros, como en la gestión por medio de las políticas de QoS. Las políticas deben permitir la variación de las características de la comunicación en función de los requisitos de control, expresados estos últimos por medio de los parámetros de QoC. A la arquitectura desarrollada se le ha llamado FSACtrl. Para determinar los requisitos de la arquitectura FSACtrl, se han estudiado las revisiones de los autores más relevantes acerca de las características más destacadas de las arquitecturas distribuidas de sistemas de control. A partir de estas características se han diseñado los elementos de la arquitectura FSACtrl. Los elementos que dan soporte a las comunicaciones se han basado en los del estándar DDS de la OMG, mientras que los elementos de control se han basado en el estándar Sensor Web Enablement (SWE) del Open Geospatial Consortium (OGC). Para la validación de la arquitectura se ha implementado un entorno de diseño y simulación del control. / Poza Luján, JL. (2012). Propuesta de arquitectura distribuida de control inteligente basada en políticas de calidad de servicio [Tesis doctoral]. Editorial Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/14674 / Palancia
70

A Framework for Interoperability on the United States Electric Grid Infrastructure

Laval, Stuart 01 January 2015 (has links)
Historically, the United States (US) electric grid has been a stable one-way power delivery infrastructure that supplies centrally-generated electricity to its predictably consuming demand. However, the US electric grid is now undergoing a huge transformation from a simple and static system to a complex and dynamic network, which is starting to interconnect intermittent distributed energy resources (DERs), portable electric vehicles (EVs), and load-altering home automation devices, that create bidirectional power flow or stochastic load behavior. In order for this grid of the future to effectively embrace the high penetration of these disruptive and fast-responding digital technologies without compromising its safety, reliability, and affordability, plug-and-play interoperability within the field area network must be enabled between operational technology (OT), information technology (IT), and telecommunication assets in order to seamlessly and securely integrate into the electric utility's operations and planning systems in a modular, flexible, and scalable fashion. This research proposes a potential approach to simplifying the translation and contextualization of operational data on the electric grid without being routed to the utility datacenter for a control decision. This methodology integrates modern software technology from other industries, along with utility industry-standard semantic models, to overcome information siloes and enable interoperability. By leveraging industrial engineering tools, a framework is also developed to help devise a reference architecture and use-case application process that is applied and validated at a US electric utility.

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