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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.
321

Uma abordagem para suporte à verificação funcional no nível de sistema aplicada a circuitos digitais que empregam a Técnica Power Gating. / An approach to support the system-level functional verification applied to digital circuits employing the Power Gating Technique.

SILVEIRA, George Sobral. 07 November 2018 (has links)
Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-11-07T17:16:29Z No. of bitstreams: 1 GEORGE SOBRAL SILVEIRA - TESE PPGEE 2012..pdf: 4756019 bytes, checksum: 743307d8794218c3a447296994c05332 (MD5) / Made available in DSpace on 2018-11-07T17:16:29Z (GMT). No. of bitstreams: 1 GEORGE SOBRAL SILVEIRA - TESE PPGEE 2012..pdf: 4756019 bytes, checksum: 743307d8794218c3a447296994c05332 (MD5) Previous issue date: 2012-08-10 / Capes / A indústria de semicondutores tem investido fortemente no desenvolvimento de sistemas complexos em um único chip, conhecidos como SoC (System-on-Chip). Com os diversos recursos adicionados ao SoC, ocorreu o aumento da complexidade no fluxo de desenvolvimento, principalmente no processo de verificação e um aumento do seu consumo energético. Entretanto, nos últimos anos, aumentou a preocupação com a energia consumida por dispositivos eletrônicos. Dentre as diversas técnicas utilizadas para reduzir o consumo de energia, Power Gating tem se destacado pela sua eficiência. Ultimamente, o processo de verificação dessa técnica vem sendo executado no nível de abstração RTL (Register TransferLevel), com base nas tecnologias CPF (Common Power Format) e UPF (Unified Power Format). De acordo com a literatura, as tecnologias que oferecem suporte a CPF e UPF, e baseadas em simulações, limitam a verificação até o nível de abstração RTL. Nesse nível, a técnica de Power Gating proporciona um considerável aumento na complexidade do processo de verificação dos atuais SoC. Diante desse cenário, o objetivo deste trabalho consiste em uma abordagem metodológica para a verificação funcional no nível ESL (Electronic System-Level) e RTL de circuitos digitais que empregam a técnica de Power Gating, utilizando uma versão modificada do simulador OSCI (Open SystemC Initiative). Foram realizados quatro estudos de caso e os resultados demonstraram a eficácia da solução proposta. / The semiconductor industry has strongly invested in the development of complex systems on a single chip, known as System-on-Chip (SoC), which are extensively used in portable devices. With the many features added to SoC, there has been an increase of complexity in the development flow, especially in the verification process, and an increase in SoC power consumption. However, in recent years, the concern about power consumption of electronic devices, has increased. Among the different techniques to reduce power consumption, Power Gating has been highlighted for its efficiency. Lately, the verification process of this technique has been executed in Register Transfer-Level (RTL) abstraction, based on Common Power Format (CPF) and Unified Power Format (UPF) . The simulators which support CPF and UPF limit the verification to RTL level or below. At this level, Power Gating accounts for a considerable increase in complexity of the SoC verification process. Given this scenario, the objective of this work consists of an approach to perform the functional verification of digital circuits containing the Power Gating technique at the Electronic System Level (ESL) and at the Register Transfer Level (RTL), using a modified Open SystemC Initiative (OSCI) simulator. Four case studies were performed and the results demonstrated the effectiveness of the proposed solution.
322

Sharing big display : développement des technologies et métaphores d'interactions nouvelles pour le partage collaboratif d'affichage en groupe ouvert / Sharing big display : technology development and new interaction metaphors for collaborative sharing display in open group

Marion, Damien 21 December 2017 (has links)
Aujourd’hui, les écrans ont envahi nos quotidiens. Cette colonisation a engendré l’avènement de nouveaux écrans, les écrans de grand format. Or, ces grands écrans sont souvent utilisés comme de simples affichages statiques n’autorisant que très peu d’interaction aux utilisateurs en présence. Mais alors comment permettre des interactions multi-utilisateur et surtout quels modes et moyens d’interactions proposer afin d’interagir avec ces grands écrans ? Il faut évidemment définir des règles de collaboration : que faire si plusieurs personnes consultent la même information en même temps ? Comment permettre à un nouvel arrivant de prendre conscience de ce qu’il y a à voir alors que des utilisateurs ont déjà “transformé” l’affichage par leur utilisation courante ?Face à ces enjeux, notre travail a consisté, dans un premier temps, à tester des interactions multi-utilisateurs sur grand écran à l’aide d’un dispositif de détection et de suivi de la position et de l’orientation de la tête (head tracking) instrumenté. Nous avons ainsi mis en évidence l’importance du concept de « vision flottante » dans la recherche collaborative d’informations sur grand écran. Dans un second temps, nos recherches se sont concentrées sur le développement d’un dispositif d’head tracking permettant des interactions multi-utilisateur (jusqu’à 6 personnes), sans artefacts et sans calibrage avec un écran de grand format. Enfin, nous présentons l’étude comparative d’un même affichage tantôt statique et tantôt rendu dynamique à l’aide de notre dispositif. Cette étude est basée sur l’évaluation de l’expérience utilisateur (UX). Ainsi, nous avons pu dégager les premières recommandations concernant les métaphores d’interactions à mettre en place pour interagir avec un écran de grand format dans un contexte d’usage en groupe ouvert.Ce travail de doctorat a été consacré à la mise en avant de la faisabilité, de l’intérêt et de la proposition de premières orientations concernant la conception d’interactions multi-utilisateurs avec un écran de grand format basées sur une technique d’head tracking. / Screens have invaded our daily life. Amongst them, large displays are becoming increasingly present in public places. Sometimes, a few interaction are proposed to the users, but most of the time they are simply used as static displays. So, how to interact with these large displays and especially how to allow multi-user interactions? Of course, we have to define rules for collaboration: what we have to do if several people consult the same information at the same time? How to allow a newcomer to become aware of what there is to see when users have already "transformed" the display by their current use?First, our work consisted in testing instrumented multi-user interactions, based on a head tracking system, during a collaborative information seeking task, on a large display. In this part, we have highlighted the importance of the concept of "floating vision". Then, our research focused on the development of a head tracking system allowing intuitive interactions, without needing neither a special equipment nor individual calibration. Our system supports several users (up to six) simultaneously interacting with individualized information on a large display. Finally, we present the study of performance gain within a context of multi-user competitive consultation of information. We compare the benefit of an adaptive display (information move in front of users who are focusing on them), with a standard display. This study is based on user experience (UX) analysis. Thus, we were able to identify the first recommendations about interaction metaphors allowing intuitive interactions with a large display in an open group context.This research was devoted to highlighting the feasibility, interest and proposition of initial orientations concerning the design of multi-user interactions with large public displays based on a head tracking technique.
323

"Metodologias para geração e atualização de mosaicos de fotos aéreas no Projeto ARARA" / Methodologies for generation and updating of aerial photographs mosaics in the ARARA Project

Rodrigo Borges dos Santos 17 August 2004 (has links)
A produção de mosaicos fotográficos é uma atividade de apoio bastante importante em diversas áreas tais como a geração de mapas, o monitoramento ambiental e o gerenciamento agrícola. A fotogrametria, e em especial a aerofotogrametria, é a ciência que trata, entre outros tópicos, da geração de mosaicos através de procedimentos trabalhosos, o que torna sua manutenção uma tarefa difícil e de alto custo. O Projeto ARARA (Aeronaves de Reconhecimento Assistidas por Rádio e Autônomas) representa uma alternativa de baixo custo para a aquisição de fotografias aéreas. Câmeras digitais de pequeno formato a bordo das aeronaves permitem a obtenção automática das fotografias necessárias para a geração de mosaicos. Este trabalho propõe uma metodologia para a geração e a atualização de mosaicos compostos por fotografias aéreas oblíquas digitais e de pequeno formato, adquiridas com o auxílio das aeronaves do Projeto ARARA. As fotografias podem ser submetidas a procedimentos que associam técnicas de ortoretificação e processamento digital de imagens para corrigir suas distorções geométricas e radiométricas. A metodologia apresentada neste trabalho procura evitar a necessidade de pontos de controle no solo e focaliza a geração automática ou semi-automática dos mosaicos. Procedimentos automáticos têm o potencial de permitir a utilização de uma grande quantidade de fotografias de pequeno formato em substituição às fotografias normalmente utilizadas pela aerofotogrametria convencional. / The generation of photographic mosaics is an important activity in many areas such as map production, environment monitoring and agricultural management. Photogrammetry, and specially aero-photogrammetry, are the sciences that deal, among other subjects, with mosaic generation using time consuming procedures, making the maintenance and updating of photographic mosaics a difficult and high-cost task. The ARARA Project (Autonomous and Radio Assisted Reconaissance Aircrafts), presents a low cost alternative to acquire aerial photographs. An onboard, small format digital camera can take automatically the photographs used for the mosaic generation. This work proposes a methodology for mosaic generation and updating using oblique, digital, small format aerial photographs taken by ARARA aircraft. Photographs can be corrected both geometrically and radiometrically by orthorectification and digital image processing procedures. The methodology presented in this work avoids the use of ground control points, focusing on the automatic and semi-automatic mosaic generation. An automatic procedure make possible the use of a large number of small format photographs to replace the photographs normally used in conventional aerophotogrammetry.
324

Estudo de sistemas com multiportadoras ópticas ortogonais e coerentes / Study of systems with optical orthogonal multicarrier and consistent

Rafael Jales Lima Ferreira 27 March 2013 (has links)
Neste trabalho a técnica de multiportadoras OFDM (Orthogonal Frequency Division Multiplexing), aplicada a sistemas ópticos, é estudada, com foco principal na geração e transmissão dos chamados supercanais ópticos modulados em altíssimas taxas (até Terabits/s). O OFDM prevê um melhor aproveitamento da largura de banda e, quando comparada à técnica FDM (Frequency Division Multiplexing), permite uma redução de aproximadamente 50% do espectro ocupado. Esta economia proporcionada pela técnica torna-a forte candidata para uso em redes ópticas reconfiguráveis, pois provê melhor eficiência espectral aos sinais com reconfiguração de tráfego remoto. Dois cenários serão abordados: o primeiro, em que o sinal com multiportadoras moduladas de forma híbrida (QAM - quadradure amplitude modulation) é gerado no domínio elétrico para, em seguida, modular uma portadora óptica; e o segundo, no qual as multiportadoras são geradas no domínio óptico e, posteriormente, moduladas individualmente também no domínio óptico - e neste caso o formato de modulação pode variar. Para o segundo caso, três técnicas de geração de supercanais serão estudadas e avaliadas a fim de se realizar uma comparação entre elas. Neste trabalho também serão comparadas as técnicas de recepção óptica direta e coerente, aplicadas a sistemas OFDM. Os resultados para o estudo da geração de multiportadoras ópticas, obtidos através de simulações no software Optisystem v. 9.0, são validados por resultados experimentais obtidos no Laboratório de Comunicações Ópticas da Fundação CPqD. / This manuscript presents a study on the multicarrier modulation technique OFDM (Orthogonal frequency division multiplexing) applied to optical systems. The OFDM technique provides a better use of bandwidth and, compared with FDM (Frequency Division Multiplexing), provides a nearly 50% reduction of the occupied bandwidth. This feature makes the OFDM technique an ideal candidate for reconfigurable optical networks because it allows better spectral efficiency to the signals with remote traffic reconfiguration. The study focuses, mainly, on the theoretical investigation of OFDM applied to the transmission of the so-called optical superchannels, modulated at very high bit rates (above Terabits/s). Two scenarios are discussed: in the first, the multicarrier signal, modulated in a hybrid format (QAM - quadrature amplitude modulation), is generated in the electrical domain before modulating the optical carrier, and in the second the multicarrier beam is generated in the optical domain and subsequently each subcarrier is digitally modulated. In this second approach, three superchannel generation techniques are studied and evaluated for being compared. This work will also compare the direct and coherent detection techniques applied to OFDM systems. The results for the optical multicarrier generation study, obtained by numerical simulation (platform Optisystem v. 9.0), are validated by experimental results obtained at the Laboratory of Optical Communication CPqD Foundation.
325

Modulation formats and digital signal processing for fiber-optic communications with coherent detection

Fickers, Jessica 12 September 2014 (has links)
A débit de données élevé, typiquement supérieur à 10 Gsymboles/s, les lignes de<p>télécommunication optique à fibre monomode souffrent de façon accrue des distorsions<p>inhérentes à la fibre et à l’architecture de transmission. Nous pouvons classer les<p>effets de fibre en plusieurs catégories:<p>– Les effets linéaires. La dispersion chromatique est entraînée par la dépendance en<p>fréquence de l’indice de réfraction de la fibre. Il en résulte un élargissement des<p>bits optiques. La dispersion des modes de polarisation prend son origine dans<p>la biréfringence de la fibre. La modélisation de cet effet est compliquée par son<p>caractère stochastique et variable dans le temps.<p>– Les effets non linéaires prennent leur origine dans un indice de réfraction de<p>fibre qui dépend du champ optique. Ces effets peuvent être classés en deux<p>catégories. Premièrement, les effets intérieurs à un canal dont le plus influant<p>est l’automodulation de phase qui découle de l’effet Kerr optique :l’intensité<p>d’une impulsion lumineuse influence sa propre propagation. Deuxièmement, il<p>existe des conséquences de l’effet Kerr par lesquelles les différents canaux, se<p>propageant au sein de la même fibre, s’influencent mutuellement. Le phénomène<p>le plus influent parmi ces derniers est la modulation de phase croisée :l’intensité<p>d’un canal influence la propagation dans un canal voisin.<p>– Les pertes par diffusion Rayleigh sont compensées par les amplificateurs distribués<p>le long de la ligne de transmission. L’amplification optique par l’intermédiaire<p>d’émission stimulée dans des dispositifs dopés aux ions Erbium est<p>accompagnée d’émission spontanée amplifiée. Ceci entraîne la présence d’un<p>bruit blanc gaussien se superposant au signal à transmettre.<p>– La gestion des canaux dans le réseau optique implique la présence dans les noeuds<p>du réseau de filtres de sélection, des multiplexeurs et démultiplexeurs.<p>Nous examinerons aussi les effets de ligne non inhérents à la fibre mais à l’architecture<p>de transmission. Les modèles de l’émetteur et du récepteur représentent les imperfections<p>d’implémentation des composants optiques et électroniques.<p>Un premier objectif est de définir et évaluer un format de modulation robuste aux<p>imperfections introduites sur le signal par la fibre optique et par l’émetteur/récepteur.<p>Deux caractéristiques fondamentales du format de modulation, determinants pour la<p>performance du système, sont étudiés dans ce travail :<p>– La forme d’ onde. Les symboles complexes d’information sont mis en forme par<p>un filtre passe-bas dont le profil influence la robustesse du signal vis-à-vis des<p>effets de ligne.<p>– La distribution des fréquences porteuses. Les canaux de communication sont<p>disposés sur une grille fréquentielle qui peut être définie de manière électronique<p>par traitement de signal, de manière optique ou dans une configuration hybride.<p>Lorsque des porteuses optiques sont utilisées, le bruit de phase relatif entre lasers<p>entraîne des effets d’ influence croisée entre canaux. En revanche, les limites des<p>implémentations électroniques sont données par la puissance des architectures<p>numériques.<p>Le deuxième objectif est de concevoir des techniques de traitement numérique du<p>signal implémentées après échantillonnage au récepteur afin de retrouver l’information<p>transmise. Les fonctions suivantes seront implémentées au récepteur :<p>– Les techniques d’estimation et d’égalisation des effets linéaires introduits par la<p>fibre optique et par l’émetteur et le récepteur. Le principe de l’égalisation dans<p>le domaine fréquentiel est de transformer le canal convolutif dans le domaine<p>temporel en un canal multiplicatif qui peut dès lors être compensé à une faible<p>complexité de calcul par des multiplications scalaires. Les blocs de symboles<p>émis doivent être rendus cycliques par l’ajout de redondance sous la forme d’un<p>préfixe cyclique ou d’une séquence d’apprentissage. Les techniques d’égalisation<p>seront comparées en termes de performance (taux d’erreurs binaires, efficacité<p>spectrale) et en termes de complexité de calcul. Ce dernier aspect est particulièrement<p>crucial en vue de l’optimisation de la consommation énergétique du<p>système conçu.<p>– Les techniques de synchronisation des signaux en temps/fréquence. Avant de<p>pouvoir égaliser les effets linéaires introduits dans la fibre, le signal reçu devra<p>être synchronisé en temps et en fréquence sur le signal envoyé. La synchronisation<p>est généralement accomplie en deux étapes principales :l’acquisition réalisée<p>avant de recevoir les symboles d’information don’t l’objectif est une première<p>estimation/compensation des effets de manière "grossière", le tracking réalisé en<p>parallèle à l’estimation des symboles d’information dont l’objectif est l’estimation<p>/compensation des effets de manière "fine". Les algorithmes d’acquisition et<p>de tracking peuvent nécessiter l’envoi d’informations connues du récepteur.<p>– Les techniques d’estimation et de compensation des imperfections de fonctionnement<p>de l’émetteur et du récepteur. Une structure de compensation des effets<p>introduits par les composants optiques et électroniques sera développée afin de<p>relâcher les contraintes d’implémentation de l’émetteur et du récepteur.<p>Etant donné la très haute cadence à laquelle les échantillons du signal sont produits<p>(plusieurs dizaines de Gech/s), une attention particulière est portée à la complexité de<p>calcul des algorithmes proposés. / Doctorat en Sciences de l'ingénieur / info:eu-repo/semantics/nonPublished
326

Tierwohl in der Fleischbranche Label - Verbrauchereinstellungen - Vermarktungswege / Animal welfare in the meat industry: Labels - Consumer attitudes - Marketing channels

Pirsich, Wiebke 08 May 2017 (has links)
No description available.
327

PDF Receipts: A micro-based-payment web service

Ho, Yu-Feng 01 January 2004 (has links)
The purpose of this project is to design, build and implement an instance of a specified online payment system, which is based on micro-payments. The three components for this system are a bookstore, a receipt service and a currency issuer.
328

Automatizovaná rekonstrukce webových stránek / Automatic Webpage Reconstruction

Serečun, Viliam January 2018 (has links)
Many legal institutions require a burden of proof regarding web content. This thesis deals with a problem connected to web reconstruction and archiving. The primary goal is to provide an open source solution, which will satisfy legal institutions with their requirements. This work presents two main products. The first is a framework, which is a fundamental building block for developing web scraping and web archiving applications. The second product is a web application prototype. This prototype shows the framework utilization. The application output is MAFF archive file which comprises a reconstructed web page, web page screenshot, and meta information table. This table shows information about collected data, server information such as IP addresses and ports of a device where is the original web page located, and time stamp.
329

Návrh územního plánu pro obec Radešín / Design of district structure plan Radešín

Moučka, Michal January 2020 (has links)
Town and country planning is an activity which is trying to find and create the most suitable conditions for the use and spatial arrangement of the territory based on comprehensive knowledge of various disciplines and therefore we rank it among multidisciplinary disciplines. The result of efforts is to ensure the sustainable development of the territory which is frequently highlighted in connection with town and country planning. The diploma thesis solves the issue of town and country planning from the point of view of the Act on town and country planning and building code with focusing on its tools. One of the tools of town and country planning is the subject of the main part of the diploma thesis which deals with the specific design of the local zoning plan of the village Radešín.
330

Ultrazvukové měření velkoformátových obkladů / Ultrasonic measurement of large format tiles

Čaněk, Michal January 2021 (has links)
The diploma thesis deals with influence of the used adhesive to large format tiles properties after installation. Properties on large format tiles were monitored by ultrasonic pulse velocity method. Hydraulic setting adhesives were tested in second part. Strength and modulus of elasticity were tested. The development of shrinkage over time was also monitored. The results were summarized in tabular and graphical form and were examined by simple statistical analysis to determine resulting conclusions.

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