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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.
131

GeoGebra no clique e na palma das m?os: contribui??es de uma din?mica de aula para constru??o de conceitos geom?tricos com alunos do ensino fundamental / GeoGebra on click and in your hands? palm: contributions of classroom?s dynamics for constructing geometric concepts with elementary students

HENRIQUE, Marcos Paulo 27 January 2017 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2018-06-13T18:03:48Z No. of bitstreams: 1 2017 - Marcos Paulo Henrique.pdf: 3532368 bytes, checksum: 3f54ade5dd907b58b5188d1e09da2e44 (MD5) / Made available in DSpace on 2018-06-13T18:03:50Z (GMT). No. of bitstreams: 1 2017 - Marcos Paulo Henrique.pdf: 3532368 bytes, checksum: 3f54ade5dd907b58b5188d1e09da2e44 (MD5) Previous issue date: 2017-01-27 / This investigation is focused on the development of activities, implementation (in the computer lab and in the classroom) and the analysis of learning of students in the 8th and 9th year of a public school in the city of Rio Claro (RJ). Specifically, the research considered the conceptual development in a teaching practice that values the dialogue, debate and writing, among other ways of registration, in a reflection with activities from the use of traditional GeoGebra (desktop) and GeoGebra application (version for smartphones). This analysis was not done to compare the two environments used, but identify contributions and challenges linked to the implementation of these resources for appropriation of knowledge. The concepts were polygons, regular polygons and parallel lines with a transverse. Data collection was carried out as follows: (a) audio recording, activities, geometric constructions files, photographic records and researcher's journal (implementation in the lab) and (b) audio and video recording, smartphones? screen capture used by students, and daily activities sheet of researcher (implementation in the classroom). In implementations of activities with computers, are highlighted the various forms of visualization and construction around the geometric object provided by dynamic geometry environment and mediation, as a tool of teaching work, as some contributions to the construction and development of the concept of regular polygon. It was observed during the implementation of the survey, some difficulties presented by the students related to handling of GeoGebra on a computer, as well as challenges to implementation of pedagogical practices in the computer lab, where multiple computers were defective. As contributions in the implementation of activities, stands out the motivator appeal, particularly, in working with parallel lines cut by transversal, using GeoGebra application. The experience showed and proved exciting, allowing the students to conclude that there are a set of elements (angles, straight position etc.), variants and invariants, along with the use and exploration of forms handled. As challenges, you can point out the difficulty of viewing properties in a building for cases where smartphone screen is small. / A presente investiga??o centrou-se na elabora??o de atividades, na implementa??o (no laborat?rio de inform?tica e em sala de aula) e na an?lise do aprendizado de alunos do 8? e 9? ano do Ensino Fundamental de uma escola p?blica de Rio Claro (RJ). Especificamente, a pesquisa analisou o desenvolvimento conceitual em uma pr?tica docente que valoriza o di?logo, a argumenta??o e a escrita, entre outras formas de registro em uma reflex?o com atividades a partir da utiliza??o do GeoGebra convencional (desktop) e o GeoGebra aplicativo (vers?o para smartphones). A an?lise n?o consiste em comparar os dois ambientes utilizados, mas identificar contribui??es e desafios atrelados ? implementa??o destes recursos para apropria??o do conhecimento. Os conceitos foram pol?gonos, pol?gonos regulares e retas paralelas com uma transversal. A coleta de dados foi realizada da seguinte maneira: (a) grava??o em ?udio, folha de atividades, os arquivos referentes ?s constru??es geom?tricas, registros fotogr?ficos e di?rio do pesquisador (implementa??o no laborat?rio) e (b) grava??o em ?udio e v?deo, captura da tela dos smartphones utilizados pelos estudantes, folha de atividades e di?rio do pesquisador (implementa??o em sala de aula). Em rela??o ?s implementa??es de atividades com computadores, destacamos as v?rias formas de visualiza??o e constru??o de um objeto geom?trico proporcionado pelo ambiente de geometria din?mica e a media??o, como ferramenta do trabalho docente, como algumas contribui??es para a constru??o e desenvolvimento do conceito de pol?gono regular. Observamos dificuldades apresentadas pelos estudantes no que se refere ao manuseio do GeoGebra em um computador, assim como desafios para implementa??o de pr?ticas pedag?gicas no laborat?rio de inform?tica, como v?rios computadores com defeito. Como contribui??es do smartphone na implementa??o de atividades, destacamos o apelo motivador que este recurso traz ?s aulas. Particularmente, no trabalho com retas paralelas cortadas por transversais, o uso GeoGebra aplicativo mostrou-se instigante por permitir aos alunos a observa??o de um conjunto de elementos (?ngulos, posi??o de retas etc.) variantes ou invariantes e, juntamente com o manuseio e explora??o das formas manuseadas. Como desafios ? poss?vel apontar a dificuldade de visualiza??o de propriedades em um constructo para casos em que a tela do smartphone ? pequena.
132

Fundamental Studies on Direct Injection Nebulisers for Sample Introduction in ICP Spectrometry : Aerosol Properties, ICP Characteristics and Analytical Performance

Goitom Asfaha, Daniel January 2006 (has links)
<p>The performance of different types of nebulisers: Vulkan direct injection nebuliser (Vulkan DIN), direct injection high efficiency nebuliser (DIHEN), microconcentric nebuliser coupled to cyclonic or double pass spray chamber (MCN-C or MCN-DP, respectively) was investigated and compared when used for sample introduction to ICP-MS or ICP-OES. With ICP-OES, in axial viewing mode, intensity distributions across the radius of the plasma (radial intensity profiles) were determined for different spectral lines with Esum 1.85-15.41 eV to determine fundamental plasma properties for various matrices using Vulkan DIN and MCN-C. The results showed that with the MCN-C the ionisation temperature (Tion) was about the same across the measured region of the plasma (±3.0 mm) whereas with the Vulkan DIN the Tion was significantly lower in the centre of the plasma. A large deviation from local thermodynamic equilibrium, as well as deteriorated stability, was observed for the plasma when using the Vulkan DIN.</p><p>With ICP-MS noise power spectra (NPS) were generated to identify sources of noise. NPS showed that the magnitude of white noise for the tested sample introduction systems decreased in the following order: Vulkan DIN > DIHEN > MCN-C > MCN-DP. This order follows the decrease of mean droplet size and span of the size distribution, indicating that the white noise is caused by spatial and temporal non-uniform desolvation and ionisation. Another source of noise arose from the peristaltic pump and the magnitude of pump interference noise decreased in the following order: DIHEN > MCN-C/DP > Vulkan DIN. Mains power interference noise and 1/f noise were lower for the direct injection nebulisers compared to the spray chamber systems. The contribution or effects of these noise components on relative standard deviations of steady-state ion-count rate and isotope ratio measurements is discussed in this thesis.</p><p>Aerosols generated by the Vulkan DIN and the DIHEN were also directly characterised using Particle Dynamic Analysis. The Vulkan DIN produced particles with a mean diameter of ~30 µm and a size distribution between 2-80 µm. With the DIHEN the corresponding values were ~11 µm and 1-40 µm, respectively, with a few particles at 55-78 µm. The mean velocity of particles from the Vulkan DIN was ~10 m s-1 and from the DIHEN ~18 m s-1. The lower velocity allows longer residence time counteracting the effects of the larger droplet size.</p>
133

Fundamental Studies on Direct Injection Nebulisers for Sample Introduction in ICP Spectrometry : Aerosol Properties, ICP Characteristics and Analytical Performance

Goitom Asfaha, Daniel January 2006 (has links)
The performance of different types of nebulisers: Vulkan direct injection nebuliser (Vulkan DIN), direct injection high efficiency nebuliser (DIHEN), microconcentric nebuliser coupled to cyclonic or double pass spray chamber (MCN-C or MCN-DP, respectively) was investigated and compared when used for sample introduction to ICP-MS or ICP-OES. With ICP-OES, in axial viewing mode, intensity distributions across the radius of the plasma (radial intensity profiles) were determined for different spectral lines with Esum 1.85-15.41 eV to determine fundamental plasma properties for various matrices using Vulkan DIN and MCN-C. The results showed that with the MCN-C the ionisation temperature (Tion) was about the same across the measured region of the plasma (±3.0 mm) whereas with the Vulkan DIN the Tion was significantly lower in the centre of the plasma. A large deviation from local thermodynamic equilibrium, as well as deteriorated stability, was observed for the plasma when using the Vulkan DIN. With ICP-MS noise power spectra (NPS) were generated to identify sources of noise. NPS showed that the magnitude of white noise for the tested sample introduction systems decreased in the following order: Vulkan DIN &gt; DIHEN &gt; MCN-C &gt; MCN-DP. This order follows the decrease of mean droplet size and span of the size distribution, indicating that the white noise is caused by spatial and temporal non-uniform desolvation and ionisation. Another source of noise arose from the peristaltic pump and the magnitude of pump interference noise decreased in the following order: DIHEN &gt; MCN-C/DP &gt; Vulkan DIN. Mains power interference noise and 1/f noise were lower for the direct injection nebulisers compared to the spray chamber systems. The contribution or effects of these noise components on relative standard deviations of steady-state ion-count rate and isotope ratio measurements is discussed in this thesis. Aerosols generated by the Vulkan DIN and the DIHEN were also directly characterised using Particle Dynamic Analysis. The Vulkan DIN produced particles with a mean diameter of ~30 µm and a size distribution between 2-80 µm. With the DIHEN the corresponding values were ~11 µm and 1-40 µm, respectively, with a few particles at 55-78 µm. The mean velocity of particles from the Vulkan DIN was ~10 m s-1 and from the DIHEN ~18 m s-1. The lower velocity allows longer residence time counteracting the effects of the larger droplet size.
134

Neukonzeption und Implementierung einer Newsletterkomponente für das Content Management System Joomla 1.5.x

Butschke, Mandy 28 March 2010 (has links) (PDF)
Joomla! ist eines der beliebtesten Open Source Web Content Management Systeme. Seine Popularität verdankt das System vor allem den vielfältigen Möglichkeiten zur Anpassung der Applikation an die individuellen Bedürfnisse der Nutzer unter Anwendung zahlreicher Erweiterungen. Mit Einführung der Version 1.5 wurde jedoch ein nahezu vollständig überarbeitetes System veröffentlicht, welches nunmehr einen durchgehend objektorientierten Ansatz verfolgt und Erweiterungen entsprechend der Model-View-Controller Architektur umsetzt. Dies hat zur Folge, dass eine Vielzahl bereits bestehender Erweiterungen nicht mit Joomla! 1.5 kompatibel sind. So auch die Newsletter-Komponente MkPostman 1.6 Beta des Chemnitzer Unternehmens „das Medienkombinat“. Die Firma stellte daher die Aufgabe, die Erweiterung im Rahmen einer Masterarbeit auf Basis des bestehenden Newsletter-Systems an das neue Joomla!-Framework anzupassen. Das Hauptaugenmerk lag dabei auf der Implementierung der überarbeiteten Erweiterung. Die vorliegende Ausarbeitung erläutert jedoch weniger die technischen Details dieser Umsetzung, sondern stellt die theoretischen Überlegungen und damit den Hintergrund der Entstehung des neuen Newsletter-Systems in den Mittelpunkt. So versucht sie zunächst ein Verständnis für das Potential, aber auch die Anforderungen eines Newsletter-System aufzubauen, indem wichtige ökonomische, rechtliche und technische Aspekte betrachtet werden. Im Zuge dessen wird näher auf den Begriff des Newsletters eingegangen. Weiterhin ist eine kurze Einführung in das Gebiet des Content Managements essentiell, um aufzuzeigen, worin dessen Idee liegt und wie diese mit Hilfe von Software umgesetzt werden kann. Dabei werden nicht nur der allgemeine Aufbau und die Funktionalitäten eines Content Management Systems genauer in Augenschein genommen, sondern vor allem das Open Source Web Content Management System Joomla! kurz vorgestellt. Um eine genauere Vorstellung davon zu bekommen, welche Mindestanforderungen an die neu zu entwickelnde Newsletter-Anwendung gestellt werden, folgt eine Untersuchung der aktuellen Komponente MkPostman 1.6 Beta hinsichtlich ihres Funktionsumfangs und ihrer Beschaffenheit. Ferner werden die Ergebnisse einer Beurteilung der Gebrauchstauglichkeit des Systems aus Sicht der derzeitigen Anwender präsentiert und die Erfordernisse der Nutzer an die neu zu entwickelnde Erweiterung ermittelt. Basierend auf den bis dahin getätigten Erkenntnissen erfolgt schließlich die Konzeption des neuen Newsletter-Systems, welches sowohl bereits bestehende als auch neue Elemente integriert. Dabei werden in erster Linie der anvisierte Aufbau sowie einige wichtige Funktionalitäten dargestellt. Schlussendlich wird kurz erläutert, wie die geplanten Grundfunktionen umgesetzt wurden und welche Möglichkeiten sich im Zuge einer Weiterentwicklung des entstandenen Systems ergaben.
135

Politicized Historiography and the Zionist-Crusader Analogy

Kellman, Emma 01 January 2014 (has links)
This study offers a look at the ways in which discourse shaped by the contemporary Israel-Palestine conflict serves as a framework for modern historiography on Palestine. It focuses specifically on the variety of historical narratives proffered as to the “truth” of the Crusade period in Palestine, roughly the eleventh through the thirteenth centuries, and their mobilization in political agendas through the Zionist-Crusader analogy. This comparison, a historical analogy likening Zionists to Frankish Crusaders or the State of Israel to the Latin Kingdom of Jerusalem, appears frequently in contemporary dialogue on the Israel-Palestine conflict; it comes from a diverse range of sources and for a variety of political ends, showing that the politicization of history of the contested land is a widespread phenomenon that is limited neither to academic nor political circles. Furthermore, this study argues that common national, religious, or ethnic identities do not guarantee common political conclusions or agreement on the “facts” of the Crusader past. On a broader level, this study investigates the theoretical underpinnings of national histories and their employment as political devices in nationalist movements, as well as explores the role of individual agency in creating and deploying nationalist historical narratives within the framework of the Zionist-Crusader analogy. In the specific context of the Israel-Palestine conflict and the modern State of Israel, this theoretical component focuses primarily on applications of Crusade history to supporting or challenging contemporary political-religious claims to the land of Israel-Palestine.
136

Nachweis von Salmonella und Yersinia enterocolitica im persistent infizierten Schwein

Arnold, Thorsten 28 November 2004 (has links) (PDF)
Die Infektion mit Salmonella und Yersinia (Y.) enterocolitica über Produkte tierischen Ursprungs stellt nach wie vor ein ungelöstes Problem des gesundheitlichen Verbraucherschutzes dar. Will man diese Zoonoseerreger aus der Lebensmittelkette fernhalten, sind moderne und gut validierte Nachweissysteme erforderlich. Eine Infektion von Schweinen erfolgt überwiegend im Mastbetrieb mit Infektionsdosen, die nur zu einer milden klinischen Symptomatik führen. In den meisten Fällen überstehen die Tiere die Infektion mit Salmonella und Y. enterocolitica und werden zu klinisch inapparenten Keimträgern. Solche Schweine stellen ein Reservoir für die Infektion anderer Tiere und für den Eintrag in die Lebensmittelkette dar. Im Rahmen dieser Arbeit wurden zwei PCR-Methoden zum spezifischen Nachweis von Salmonella und Y. enterocolitica im Schlachtschwein entwickelt und anhand von Probenmaterial aus eigens dafür durchgeführten Infektionsversuchen mit S. Typhimuirum und Y. enterocolitica evaluiert. Beide Methoden mussten sich am diagnostischen Goldstandard für den jeweiligen Erreger messen lassen. Für Salmonella Typhimurium wurde die ISO-Norm 6579 und für Y. enterocolitica die ISO-Norm 10273 zum kulturellen Nachweis ausgewählt. Es konnte eine neue PCR-Methodik zum Salmonella-Nachweis in 14 verschiedenen Gewebeproben etabliert werden, die im Vergleich zum kulturellen Nachweis nach ISO 6579 eine Sensitivität von 100 % und eine Spezifität von 96 % aufweist und die Zeitspanne bis zum spezifischen Nachweis des Erregers um mindestens 24 Stunden reduziert. Die Untersuchungen erfolgten anhand von 420 Gewebeproben aus persistent infizierten Schweinen aus Infektionsversuchen mit S. Typhimurium DT104. Dieses neu entwickelte und validierte PCR-Verfahren wurde mit einem bereits etablierten PCR-Nachweissystem nach RAHN et al. (1992) - wie in der DIN 10135 angegeben - verglichen. Beide PCR-Methoden basieren auf dem invA-Virulenzgen von S. Typhimurium. Im Infektionsversuch konnten zwei Gewebeproben (Caecum und Lnn. Ileocolici) bestimmt werden, durch deren Kombination man mit beiden Nachweismethoden 96 % (23 von 24 Tieren) aller im Versuch infizierten Schweine als Salmonella positiv identifizieren konnte. Erstmals gelang in dieser Arbeit der Nachweis des yopT-Gens bei plasmidtragenden Y. pseudotuberculosis-Stämmen sowie die Bestimmung der Sequenz (European Bioinformatics Institute, Accession-Number: AJ304833). Das yopT-Gen kodiert für ein 35,5 kDa großes Effektor-Protein, das einen zytotoxischen Effekt auf HELA-Zellen und Makrophagen besitzt. Durch den Nachweis des yopT-Gens bei Y. pseudotuberculosis-Stämmen war es erstmals möglich, eine für Y. enterocolitica spezifische, auf dem yopT-Gen des Virulenzplasmids basierende PCR-Methode zu etablieren, die auch die Diskriminierung von Y. pseudotuberculosis-Isolaten gestattet. In einem weiteren Infektionsversuch konnte gezeigt werden, dass es die auf dem yopT-Gen von Y. enterocolitica basierende PCR-Methode erlaubt, Carrier-Tiere mit hoher Sensitivität (100 %) und Spezifität (87 %) innerhalb von 56 Stunden in lymphatischen Geweben zu identifizieren. Besonders geeignet für den Nachweis mit der ISO 10273 und dem neu etablierten yopT PCR-Verfahren waren das Ileum und die Lnn. ileocolici. In dieser Arbeit ist der Versuch gelungen, die Diagnostik für zwei der drei wichtigsten beim Schwein vorkommenden humanen Enteritiserreger zu standardisieren, indem Kombinationen aus Gewebeproben bestimmt wurden, die sowohl für den Nachweis mit der jeweiligen Goldstandard-Methode als auch mit den schnelleren und sensitiveren PCR-Methoden geeignet sind. Die Ergebnisse dieser Arbeit tragen zu einer deutlichen Verbesserung der Diagnostik von Salmonella und Y. enterocolitica beim Schlachtschwein bei. Es bleibt zu hoffen, dass somit der Eintrag dieser Zoonoseerreger in die Lebensmittelkette reduziert und der Verbraucherschutz auf diesem Gebiet beträchtlich verbessert werden kann. / The infection with Salmonella and Yersinia (Y.) enterocolitica through foodstuff from slaughter pigs is one of the major problems of hygienic consumer protection. To avoid the contamination of products from pig industry modern and well validated bacteriological identification systems are necessary. An infection predominantly occurs in the fattening pens, showing mild clinical symtoms only. The majority of infected pigs overcome the infection with Salmonella and Y. enterocolitica and become clinically inapparent carrier pigs. Those pigs are a reservoir for the contamination of other animals and pork products. In the context of this work two PCR-assays for the specific detection of Salmonella and Y. enterocolitica have been developed and validated on the basis of tissue samples from experimentally infected pigs. Both methods have been compared with the classical bacterial culture. Two international standards were used for bacterial detection: ISO 6579 for S. Typhimurium and ISO 10273 for pathogenic Y. enterocolitica. It was possible to establish a new PCR-assay for the specific detection of Salmonella in 14 different tissues of experimentally infected pigs. In comparison to the standard ISO 6579 a sensitivity of 100 % and a specificity of 96 % were calculated for the PCR-assay. The investigations were carried out with 420 tissue samples of persistently infected pigs that have been experimentally infected with S. Typhimurium. By using the PCR-method for the detection of Salmonella in positive tissue samples, the detection-time could be reduced around 24 hours. The new PCR-assay developed and validated in this work, was compared with the PCR-method described in DIN 10135, which is based on the studies of RAHN et al. (1992). Both methods were based on the invA-virulence gene of S. Typhimurium. A combination of samples from ileocolic lymph node and caecum was particularly suitable for the detection of 96 % of the experimentally infected pigs (23 off 24 animals) with the PCR-assay and the culture method. In this study, the yopT-gene was proved for the first time to be present in plasmid bearing Y. pseudotuberculosis-Isolates, and the nucleotid sequence was determined (European Bioinformatics Institute, Accession-Number: AJ304833). YopT encodes a 35.5 kDa effector protein (YopT), which induces a cytotoxic effect in HeLa cells and macrophages. This finding was used to develop a specific PCR-assay for the detection of pathogenic Y. enterocolicica strains and the discrimination from pathogenic Y. pseudotuberculosis strains. Embedded in an experimental Y. enterocolitica-infection-model in swine, it was shown that the yopT PCR-assay is suitable for the detection of pathogenic Y. enterocolitica in lymphatic tissue of persistently infected pigs. The yopT PCR-method shows a sensitivity of 100 % and a specificity of 87 % in lymphatic tissue. By the use of the PCR-assay, the detection of Y. enterocolitica was possible within 56 hours. A combination of specimens from the ileum and ileocolic lymph nodes was most suitable for the detection of pathogenic Y. enterocolitica in slaughter pigs with the ISO-Standard 10273 and the yopT PCR. This investigation succeeded in standardizing the identification of two of the three most important zoonotic agents for human enteric disease. The standardization was achived by the use of a combination of samples suitable for the identification with both, the “Goldstandard” and the specific and rapid PCR-method. The results of this work offer a better identification of Salmonella and Y. enterocolitica in slaughter pigs in the future. Based on these facts it is possible to avoid contamination of food products from slaughter pigs and to improve the hygienic consumer protection considerably.
137

&#65279;Um ambiente multi-middleware para desenvolvimento de aplica??es distribu?das

Almeida, Andr? Gustavo Duarte de 12 February 2008 (has links)
Made available in DSpace on 2014-12-17T15:47:46Z (GMT). No. of bitstreams: 1 AndreGDA.pdf: 982503 bytes, checksum: 1c9c31b9670edd5ef9e3e725bb8f680b (MD5) Previous issue date: 2008-02-12 / &#65279;This work presents a proposal of a multi-middleware environment to develop distributed applications, which abstracts different underlying middleware platforms. This work describes: (i) the reference architecture designed for the environment, (ii) an implementation which aims to validate the specified architecture integrating CORBA and EJB, (iii) a case study illustrating the use of the environment, (iv) a performance analysis. The proposed environment allows interoperability on middleware platforms, allowing the reuse of components of different kinds of middleware platforms in a transparency away to the developer and without major losses in performance. Also in the implementation we developed an Eclipse plugin which allows developers gain greater productivity at developing distributed applications using the proposed environment / &#65279;Este trabalho apresenta a proposta de um ambiente multi-middleware para desenvolvimento de aplica??es distribu?das, o qual abstrai diferentes plataformas de middleware subjacentes. O trabalho descreve: (i) a arquitetura de refer?ncia especificada para o ambiente, (ii) uma implementa??o que valida tal arquitetura integrando CORBA e EJB, (iii) um estudo de caso ilustrando o uso do ambiente, (iv) a an?lise de desempenho. O ambiente proposto permite alcan?ar interoperabilidade de plataformas de middleware, promovendo o reuso de componentes de diferentes plataformas de forma transparente para o desenvolvedor e sem perdas expressivas em termos de desempenho. Na implementa??o desenvolvemos um plugin para IDE Eclipse que permite que os eventuais desenvolvedores obtenham maior produtividade ao desenvolver aplica??es usando o ambiente
138

Instancia??o e avalia??o de um framework para a gera??o din?mica de processos / Instantiation and evaluation of a framework for dynamic process generation

Soares, Fernando Helton Linhares 05 August 2013 (has links)
Made available in DSpace on 2014-12-17T15:48:09Z (GMT). No. of bitstreams: 1 FernandoHLS_DISSERT.pdf: 2616798 bytes, checksum: 22d85c8d781aecef20ff0906635a692b (MD5) Previous issue date: 2013-08-05 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / One way to deal with the high complexity of current software systems is through selfadaptive systems. Self-adaptive system must be able to monitor themselves and their environment, analyzing the monitored data to determine the need for adaptation, decide how the adaptation will be performed, and finally, make the necessary adjustments. One way to perform the adaptation of a system is generating, at runtime, the process that will perform the adaptation. One advantage of this approach is the possibility to take into account features that can only be evaluated at runtime, such as the emergence of new components that allow new architectural arrangements which were not foreseen at design time. In this work we have as main objective the use of a framework for dynamic generation of processes to generate architectural adaptation plans on OSGi environment. Our main interest is evaluate how this framework for dynamic generation of processes behave in new environments / Uma forma de lidar com a elevada complexidade dos sistemas de software atuais ? atrav?s de sistemas autoadaptativos. Sistema autoadaptativos devem ser capazes de monitorar a si mesmos e ao seu ambiente, analisar os dados monitorados para determinar a necessidade de adapta??o, decidir como a adapta??o ser? realizada e, por fim, realizar as adapta??es necess?rias. Uma das maneiras de realizar a adapta??o de um sistema ? gerar, em tempo de execu??o, o processo que ir? executar a adapta??o. Uma vantagem dessa abordagem ? a possibilidade de levar em considera??o caracter?sticas que s? podem ser avaliadas em tempo de execu??o, como por exemplo, o surgimento de novos componentes que possibilitem novos arranjos arquiteturais que n?o foram previstos em tempo de projeto. Neste trabalho, temos como principal objetivo a utiliza??o de um framework de gera??o din?mica de processos para gerar planos de adapta??o arquiteturais sobre o ambiente OSGi. Nosso principal interesse consiste em verificar como esse framework de gera??o din?mica de processos se comporta em novos ambientes
139

Bifurca??es din?micas em circuitos eletr?nicos

Onias, Heloisa Helena dos Santos 08 1900 (has links)
Submitted by Helmut Patrocinio (hell.kenn@gmail.com) on 2017-12-01T23:43:39Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Heloisa_Onias_Dissertacao_2012.pdf: 9805428 bytes, checksum: 00e0f3bac6584320107351966c70da69 (MD5) / Approved for entry into archive by Ismael Pereira (ismael@neuro.ufrn.br) on 2017-12-04T12:33:01Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Heloisa_Onias_Dissertacao_2012.pdf: 9805428 bytes, checksum: 00e0f3bac6584320107351966c70da69 (MD5) / Made available in DSpace on 2017-12-04T12:33:37Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Heloisa_Onias_Dissertacao_2012.pdf: 9805428 bytes, checksum: 00e0f3bac6584320107351966c70da69 (MD5) Previous issue date: 2012-08 / O circuito RLD, formado por um resistor, um indutor e um diodo em s?rie, apresenta uma din?mica muito rica quando for?ado por uma tens?o externa harm?nica e vem sendo estudado h? d?cadas. Contudo, ainda existem t?picos em din?mica n?o-linear sendo estudados com variantes deste circuito. Varreduras nos par?metros de controle podem fazer com que esse sistema oscile eletronicamente entre regi?es peri?dicas e regi?es ca?ticas. O diodo ? o elemento n?o linear respons?vel pelo surgimento do caos. Utilizando um modelo de capacit?ncia n?o linear para descrever o comportamento do diodo, podemos escrever as equa??es para esse sistema e estudar a sua din?mica numericamente. Nosso principal objetivo foi o estudo de expoentes cr?ticos complexos em bifurca??es din?micas. Para isso, realizamos um estudo num?rico do circuito RLD for?ado senoidalmente utilizando como par?metros de controle a frequ?ncia e a amplitude da tens?o de entrada. Constru?mos, a partir das s?ries temporais da corrente total e da tens?o no diodo, diagramas de bifurca??o com diferentes cortes estrobosc?picos, que apresentam cascata de dobramento de per?odo, janelas peri?dicas e transi??o intermitente. Tamb?m realizamos estudos num?ricos do comportamento da m?dia na regi?o de transi??o caos-peri?dico na busca de encontrar um expoente cr?tico caracter?stico e oscilas??es na m?dia, elementos que j? foram observados no mapa log?stico. N?o foram poss?veis observar numericamente as oscila??es, mas observamos um decaimento exponencial com expoente cr?tico de aproximadamente 0,5. Montamos um sistema de controle, aquisi??o e tratamento de dados experimentais no qual ? poss?vel a realiza??o remota de experimentos simult?neos com dois circuitos diferentes. Obtivemos diagramas de bifurca??es experimentais nos quais observamos que o sistema apresentahisterese e alta sensibilidade ?s condi??es do experimento como, por exemplo, o passo de varredura do par?metro de controle. / The RLD circuit, formed by a resistor, an inductor and a diode in series, displays a very rich dynamics when forced by an external harmonic voltage, and it has being studied for decades. However, there are some topics in nonlinear dynamics that are still studied with variants of this circuit nowadays. Changes in the control parameters may cause electronic oscillations between regular and chaotic regions.The diode is the nonlinear element responsible for the appearance of chaos. Using a nonlinear capacitance model to describe the behavior of the diode, we can write the equations for this system and study its dynamics numerically. Our main objective was the study of critical exponents in complex dynamic bifurcations. For that, we did a numerical study of the RLD circuit forced sinusoidally using as control parameters the amplitude of the input voltage and the frequency. We made, from the time series obtained, bifurcation diagrams with different stroboscopic cuts, which have cascade of period-doubling, periodic windows and intermittent transition. We also did numerical studies of the average behavior in the periodic-chaos transition region searching for characteristic critical exponent and oscilas??es on average, elements that have been observed in the logistic map. It was not possible to observe the oscillations numerically, but we observed an exponential decay with critical exponent of approximately 0.5. We set up a system able to control, acquire and process experimental data making it possible to perform remote simultaneous experiments with two different circuits. We have obtained experimental diagrams bifurcations in which we observe that the system has hysteresis and high sensitivity to the conditions of the experiment such as the step of scanning the control parameter.
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Simula??o computacional de medidas estereol?gicas em estruturas de metal duro (WC-Co)

Esteves, Ezequias Matos 22 August 2011 (has links)
Made available in DSpace on 2014-12-17T14:07:08Z (GMT). No. of bitstreams: 1 EzequiasME_TESE.pdf: 4077046 bytes, checksum: 10fbafe209b02444fb805640364b456c (MD5) Previous issue date: 2011-08-22 / This work focuses on the creation and applications of a dynamic simulation software in order to study the hard metal structure (WC-Co). The technological ground used to increase the GPU hardware capacity was Geforce 9600 GT along with the PhysX chip created to make games more realistic. The software simulates the three-dimensional carbide structure to the shape of a cubic box where tungsten carbide (WC) are modeled as triangular prisms and truncated triangular prisms. The program was proven effective regarding checking testes, ranging from calculations of parameter measures such as the capacity to increase the number of particles simulated dynamically. It was possible to make an investigation of both the mean parameters and distributions stereological parameters used to characterize the carbide structure through cutting plans. Grounded on the cutting plans concerning the analyzed structures, we have investigated the linear intercepts, the intercepts to the area, and the perimeter section of the intercepted grains as well as the binder phase to the structure by calculating the mean value and distribution of the free path. As literature shows almost consensually that the distribution of the linear intercepts is lognormal, this suggests that the grain distribution is also lognormal. Thus, a routine was developed regarding the program which made possible a more detailed research on this issue. We have observed that it is possible, under certain values for the parameters which define the shape and size of the Prismatic grain to find out the distribution to the linear intercepts that approach the lognormal shape. Regarding a number of developed simulations, we have observed that the distribution curves of the linear and area intercepts as well as the perimeter section are consistent with studies on static computer simulation to these parameters. / Este trabalho versa sobre a cria??o e as aplica??es de um software de simula??o din?mica para estudo da estrutura do metal duro (WC-Co). A base tecnol?gica utilizada para amplia??o da capacidade de hardware foi a GPU Geforce 9600 GT com o chip Physx criada com o prop?sito de dar mais realismo aos jogos eletr?nicos. O software simula a estrutura tridimensional do metal duro com o formato de uma caixa c?bica onde os carbetos de tungst?nio (WC) s?o modelados como prismas triangulares e prismas triangulares truncados. O programa se mostrou eficiente em testes de verifica??o, desde c?lculos de medidas de par?metros como na capacidade de amplia??o do n?mero de part?culas simuladas dinamicamente. Foi poss?vel fazer uma investiga??o de par?metros m?dios e de distribui??es de par?metros estereol?gicos utilizados para caracterizar a estrutura do metal duro atrav?s de planos de cortes. Nos planos de cortes das estruturas analisadas foram investigados os interceptos lineares, intercepto de ?rea e per?metro de se??o dos gr?os interceptados e a fase ligante da estrutura atrav?s do c?lculo do valor m?dio e da distribui??o do livre caminho. Como a literatura ? quase consensual que a distribui??o dos interceptos lineares ? lognormal e que isso sugere que a distribui??o dos gr?os na estrutura tamb?m seja lognormal, foi desenvolvida uma rotina no programa, que possibilitou uma investiga??o mais detalhada dessa quest?o. Foi observado que ? poss?vel, sob certos valores para os par?metros que definem o formato e tamanho do gr?o prism?tico, encontrar distribui??o de interceptos lineares que se aproximam do formato lognormal. Nas v?rias simula??es desenvolvidas foi verificado que as curvas de distribui??es de interceptos lineares, de ?rea e per?metro de se??o, est?o de acordo com trabalhos na literatura de simula??o computacional est?tica desses par?metros.

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