491 |
Development of a wireless sensor system for the characterization of energy harvesting conditionsHörschmeyer, Felix January 2016 (has links)
This report deals with the development of a wireless sensor system that measures the environmental energy and predicts if energy harvesting could be possible in different areas. It provides an overview over the hardware used to build this system and gives a detailed description of the software implementation of the system. The hardware part presents the microcontroller and platform that is used, as well as the sensors integrated in the system. The software part explains how the used hardware was put together in a program that controls the different components. It explains the possibility to save captured sensor values on an SD card or send them to a remote receiver with an XBee radio module in real time. Also the inclusion of the mbed software library, which provides a lot of useful applications and functions for the project, is an important part. The final part of the report presents the results, showing how the system works.
|
492 |
Novi metod analize rada fotonaponskog sistema u uslovima varijacije sunčevog zračenja / A new method of analyzing the photovoltaic power plant works under variation of solar radiationČorba Zoltan 20 May 2016 (has links)
<p style="text-align: justify;">Rad se bavi problemom smanjenja proizvodnje<br />električne energije fotonaponske elektrane u<br />uslovima promenljivog zračenja. Predlaže se novi<br />metod analize rada u uslovima senčenja putem makro- i<br />mikrorekonfiguracije FN polja, koja povećava<br />proizvodnju električne energije.</p> / <p>The paper presents the problem of reducing electricity<br />production of PV power plant under variation of solar<br />radiation conditions. The author proposed a new method of<br />analysis PV power plant works under partial shading<br />condition trough micro- and macroconfiguration of PV array.</p>
|
493 |
Effet de l'organisation nanométrique sur les propriétés de matériaux pour piles solides au lithiumVolel, Maritza January 2004 (has links)
Thèse numérisée par la Direction des bibliothèques de l'Université de Montréal.
|
494 |
Harmonický posun výšky tónu / Harmonic pitch shiftingCihelková, Tereza January 2011 (has links)
This thesis describes the design and implementation of audio effect for pitch shifting of monophonic singing signals. The effect can generate two pitch shifted voices from input signal in real-time, while preserving formants. Amount of the shift can be controlled via MIDI controller. The effect is implemented as VST module in the form of dynamic-link library. This work also includes theoretical introduction to related DSP techniques.
|
495 |
Effet de l'incorporation de systèmes hybrides sur les propriétés mécaniques de matériaux composites à matrice époxyvinylester et polyester insaturé / Effect of the incorporation of hybrid systems on the mechanical properties of composite materials based on epoxy vinylester and unsaturated polyester matricesPoncet, Mélissa 20 March 2013 (has links)
Ce travail de thèse porte sur l'élaboration d'un matériau composite à matrice thermodurcissable incorporant des renforts nanométriques et/ou une phase élastomère, permettant d'améliorersa rigidité, son amortissement et sa résilience. Pour cela, nous avons réalisé des formulations baséessur des matrices époxyvinylester, renforcées ou non par une phase élastomère et chargées de montmorillonite ou de sépiolite. Nous avons étudié leurs propriétés visco-élastiques par analyse modaleexpérimentale et leurs propriétés à l'impact par des essais d'impact par chute de masse. Nous avonsdéterminé la microstructure des composites fabriqués en nous appuyant sur la diffraction des rayonsX et des observations en microscopie électronique. Des modèles d'homogénéisation, fondés sur lemodèle de H ALPIN -T SAI et adaptés aux matériaux composites étudiés, ont été développés afin dedisposer d'un outil permettant de relier explicitement la rigidité des composites à leur morphologie.Une analyse paramétrique approfondie a permis de déterminer les caractères morphologiques lesplus influents et d'évaluer la performance des procédés de mise en œuvre au regard des renforcements mécaniques obtenus. Expérimentalement, l'incorporation de montmorillonite ou de sépiolite a conduit à une augmentation significative du module élastique et la présence d'une phase élastomère dans la résine a permis de doubler l'amortissement et d'augmenter la résilience. Finalement, les formulations les plus performantes ont été retenues pour la fabrication de composites renforcés de fibres de verre. L'amélioration des propriétés mécaniques se retrouve, dans une moindre mesure, dans lesprototypes réalisés. La pertinence de l'utilisation de ces matériaux à l'échelle industrielle a été évaluée. / This thesis focuses on the development of a thermosetting matrix composite incorporating nanoscale reinforcements and/or an elatomeric phase to improve its stiffness, damping and resilience.To do so, we made formulations based on epoxy vinyl ester matrices, filled or not by an elastomeric phase, and reinforced with montmorillonite or sepiolite. Their viscoelastic properties were studied usingexperimental modal analysis and their impact properties were investigated using drop weight impacttesting. The microstructure of these composites was examined using X-ray diffraction and electronmicroscopy observations.Homogenization models based on H ALPIN -T SAI model and adapted to the studied composites were developed to provide a tool able to explicitly link the stiffness of the material to its morphology.A detailed parametric analysis allowed to determine the most influential morphological characteristics and to assess the efficiency of the process regarding the mechanical stiffening obtained.Experimentally, the incorporation of montmorillonite or sepiolite led to a significant increase in the elastic modulus and, with the presence of an elastomeric phase in the resin, the damping was doubled and the resilience was increased.Finally, the most efficient formulations were used to manufacture glass fibers reinforced composites.The improvement in mechanical properties was found, to a lesser extent, for the manufactured prototypes.The relevance of the use of these materials on an industrial scale was evaluated.
|
496 |
Educational leadership and the management of change in higher education : implication of module-based teaching and learning at National University of Rwanda.Nkurikiyumukiza, Phocas 10 February 2012 (has links)
On the assumption that leadership involves individuals with distinct qualities who take much ingenuity, energy and skills to trigger greater capacity in the organization for moving people towards organizational vision and goal achievement, the aim of this study is to identify and describe the leadership shown by managers and lecturers for the successful implementation of academic programme change at National University of Rwanda. That includes investigating the improvement of academic practice in the higher education institution while implementing change, i.e. introduction of the Module-Based Teaching and Learning (MBTL) methodology which is a new approach to schooling, as well as defining an appropriate leadership style needed for the management of this implementation.
The research was carried out at National University of Rwanda as a case study and supported by the aid of interviews with faculty managers and lecturers as they are the main developers and users of teaching and learning programmes. Next, data collected were complemented by means of textual analysis. The findings revealed that the MBTL introduced at NUR as an innovation in academic practice was a top-down decision made by the policy makers without consultation with academic staffs and implemented without adequate preparation whereas they are the main actors in the implementation. Coupled with the change in the language of instruction from French to English and the lack of educational material required by the MBTL approach, the situation had an unenthusiastic impact on the engagement of NUR academics for accurate successful implementation.
The overall conclusion is that inadequate management of the introduction of an educational change programme leads to misadoption and reluctance at best and resistance by the implementers at worst.
|
497 |
Módulos tipo Verma sobre álgebra TKK afim estendida / Verma type module over an extended affine TKK algebra.Sargeant, Anliy Natsuyo Nashimoto 30 March 2007 (has links)
As álgebras TKK afins estendidas pertencem à classe de álgebras de Lie chamada álgebras de Lie afins estendidas do tipo $A_1$. Elas são obtidas a partir de um semi-reticulado do $\\mathbbR^n$. Estudamos a estrutura dos módulos tipo Verma sobre a álgebra TKK afim estendida para um semi-reticulado (não-reticulado) do $\\mathbbR^2$. Quando fixamos um conjunto positivo de raízes isotrópicas chamado standard encontramos quatro órbitas da subálgebra de Borel que dão origem a distintos módulos tipo Verma sobre a álgebra TKK afim estendida. Estudamos as estruturas de seus submódulos e encontramos critérios de irredutibilidade para os módulos de Verma clássico e imaginário. / The extended affine TKK Lie algebras belong to a class of Lie algebras called extended affine Lie algebras of type $A_1$. They are obtained from a semilattice on $\\mathbbR^n$. We studied the structure of the Verma type modules for the extended affine TKK algebra obtained from a semi-lattice (non-lattice) on $\\mathbbR^2$. Fixing a set of positive isotropic roots called standard we found four orbits of the Borel subalgebra each of which give distinct Verma modules for the extended affine TKK algebra. We studied the structures of their submodules and found a criteria for irreducibility for the classic and imaginary Verma modules.
|
498 |
Ensino da leitura sob a perspectiva discursiva crítica : trabalhando com textos de campanha comunitáriaCastro, Weslin de Jesus Santos 20 February 2018 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Difficulty in reading and interpreting multimodal texts, observed through surveys conducted with students of the ninth grade of C.E.P.P.F and E. E. J. P. C. Elementary School was the starting point of the research presented in this report. The main objective was to minimize the difficulty identified among these students by reading workshops in a didactic module. Therefore, the mobilized theoretical contribution allowed the reflection on the observed reading difficulty, the elaboration of an intervention proposal and the discussion of the results. This theoretical support is based on authors such as: Cassano (2003), who explains about reading in a discursive perspective; Kleiman (2008, 2010, 2012), who brings reflections around literacy; Lerner (2002), who analyzes the school reading situation; Fairclough (2001), who deals with the three-dimensional model of critical discourse analysis; Rojo (2012), who discusses multiliteracies; Silvestre and Vieira (2015) and Dionísio (2014), who discuss multimodality studies; Novellino (2007), who inventories instruments of Kress and Van Leeuwen visual grammar (2006 [1996]) for the interpretation of multimodal texts. The applied methodology was the educational action research that, according to Tripp (2005), entails a greater integration of the production of theoretical knowledge to the analysis and reformulation of praxis in the face of a demand verified by the teacher in a given group of students. The instruments used for the collection, description and analysis of information consisted of initial and final reading tests and evaluation activities for each workshop. The results showed that this research had repercussions on the literacy of the involved students in the interpretation of multimodal texts. The final product of this research consists of a Didactic Module intended for Portuguese teachers and susceptible of being replicated for reading practice in Elementary School. / A dificuldade de ler e interpretar textos multimodais, observada por meio de sondagens realizadas com alunos do nono ano do Ensino Fundamental do C.E.P.P.F e da E. E. J. P. C., constituiu o ponto de partida da pesquisa apresentada neste relatório. Esta teve como objetivo principal intervir na minimização da lacuna identificada entre esses alunos mediante a realização de oficinas de leitura reunidas em um módulo didático. Para tanto, o aporte teórico mobilizado permitiu a reflexão sobre a dificuldade de leitura observada, a elaboração de uma proposta de intervenção e a discussão dos resultados. Esse aporte se baseia em autores como: Cassano (2003), que explana sobre a perspectiva discursiva da leitura; Kleiman (2008, 2010, 2012), que traz reflexões em torno do letramento; Lerner (2002), que analisa a situação escolar da leitura; Fairclough (2001), que trata do modelo tridimensional de análise crítica do discurso; Rojo (2012), que discute sobre os multiletramentos; Silvestre e Vieira (2015) e Dionísio (2014), que discorrem sobre os estudos de multimodalidade; Novellino (2007), que repertoria instrumentos da gramática visual de Kress e Van Leeuwen (2006 [1996]) para a interpretação de textos multimodais. A metodologia aplicada foi a pesquisa-ação educacional que, segundo Tripp (2005), enseja uma maior integração da produção do conhecimento teórico à análise e à reformulação da práxis diante de uma demanda verificada pelo professor em um dado grupo de alunos. Os instrumentos utilizados para a coleta, descrição e análise das informações se constituíram de testes inicial e final de leitura e de atividades avaliativas para cada oficina. Os resultados obtidos demonstraram que a realização desta pesquisa repercutiu no letramento dos alunos envolvidos na interpretação de textos multimodais. O produto final desta pesquisa consiste em um Módulo Didático destinado a professores de língua portuguesa e suscetível de ser replicado para o trabalho com leitura no Ensino Fundamental. / São Cristóvão, SE
|
499 |
Metodologia computacional para análise óptica de células fotovoltaicas encapsuladasDefferrari, Carolina Schumacher January 2017 (has links)
As ferramentas computacionais utilizadas em diferentes áreas de pesquisa têm como vantagem sobre análises e ensaios reais a possibilidade de analisar sistemas em diferentes condições de forma mais ágil e com menor consumo de tempo e recursos. A modelagem óptica de dispositivos fotovoltaicos é bastante difundida. Existem diferentes trabalhos na área, com diferentes escopos e graus de detalhamento, que permitem a análise e melhor compreensão das diferentes etapas da conversão da radiação em energia elétrica, expandindo as possibilidades de otimização. No presente trabalho foi desenvolvida, em uma etapa inicial, uma metodologia computacional para análise óptica de módulos fotovoltaicos, para então, em uma segunda etapa, serem realizados estudos do desempenho de diferentes materiais inseridos no conjunto de camadas que compõe os módulos, através da metodologia. O modelo óptico que embasa o método tem como foco os módulos de silício monocristalino. Esses módulos agregam de três a quatro camadas transparentes sobre as células fotovoltaicas. Ao incidir nesse conjunto de camadas radiação é submetida a diferentes eventos de extinção, como função do comprimento de onda da radiação e ângulo de incidência, que devem ser previstos em um modelo de forma a obter-se resultados válidos de transmissividade. A metodologia propõe a realização de uma análise aprofundada dos fenômenos ópticos que ocorrem mediante a incidência de radiação em um módulo fotovoltaico de modo a auxiliar na análise da adequação e desempenho de diferentes materiais ao sistema óptico formado. A otimização da transmissão de radiação em um módulo fotovoltaico tem uma influência direta e significativa sobre a eficiência de tais dispositivos, justificando sua importância. A validação do modelo foi realizada através da literatura, em partes, e apresentou coerência com os resultados de referência. Foram produzidos na segunda etapa estudos de desempenho de materiais ou propriedades isoladamente. No primeiro estudo foram analisados três materiais para aplicação como filme de passivação sobre a célula, sendo eles Si3N4, SiO2, e TiO2; o filme de Si3N4 apresentou o melhor desempenho. O segundo estudo, de avaliação da influência do índice de refração do encapsulante na transmissividade do sistema, demonstrou que a variação desse parâmetro tem muito pouca influência. No terceiro estudo foi analisado o potencial dos materiais PDMS e TiO2 como filmes anti-reflexo sobre vidro. O PDMS gerou melhores resultados de transmissividade. Por fim um estudo de desempenho de um conjunto de materiais frente à mudança do espectro incidente foi realizado. Foi utilizado até então o espectro de referência, que foi então comparado a um espectro médio de um dia de equinócio da cidade de Porto Alegre. O desempenho do sistema foi em torno de 3% inferior em incidência normal. / Computational tools raise the possibility of studying and understanding systems under different conditions in a faster and less resource and time consuming way. The optical modeling of photovoltaic devices is a very developed issue, and paperworks and projects in different scopes e levels of detail were produced, providing a better understanding of the different steps of converting light into electricity, expanding optimization possibilities. For this project a computational methodology was developed, as an initial step, for the optical assessment of the transmission of radiation in photovoltaic modules. In a second step, studies were performed using the method as a tool for analyzing the system formed by the layers covering the cells embedded in modules. The optical model describes monocristalline silicon modules, which are constituted by three to four layers covering the cell. Once it penetrates the set of layers, incident light suffers different extinction phenomena, which are predicted in this model in order to generate valid results. It’s a function of wavelength and incidence angle of the incoming radiation. The model presented aims to deeply analyse and understand the optical phenomena light undergoes through its way from the external environment to the interior of the cell, supporting the process of observing the performance and adequacy of different materials as the referred layers. Optimizing transmission of radiation in a photovoltaic device plays a main role in increasing the efficiency of the energy conversion process, which is why it’s so important. The model was validated by literature in parts, and showed coherence within reference results. Studies were produced in a second step of this work, using the method, concerning optical issues, for the thin film on top of the cell, the refractive index of the encapsulating material, and the optical effect of coating the outer glass surface. In the first study Si3N4, SiO2 and TiO2 were analyzed; the Si3N4 film produced the best results. The second study, concerning encapsulant’s refractive index, demonstrates this parameter has a very weak influence in the system’s transmission. The third one observed the performance of two materials, PDMS and TiO2, as AR coating,. The PDMS film produced a better effect. At last, the best performance set of layers was analyzed under a representative spectral distribution of an equinox day of the city of Porto Alegre, considering so far it was used the standard. The transmission suffered a slight decrease, around 3%.
|
500 |
Uma linha de produto de software para módulos de aprendizagem interativa / A software product line for interactive learning modulesDalmon, Danilo Leite 06 July 2012 (has links)
Aplicativos educacionais podem promover diversos benefícios a professores e alunos, desde a redução de tarefas repetitivas à realização de atividades impossíveis com o uso de apenas lousa e papel. Módulos de Aprendizagem Interativa (iMA) são uma família de aplicativos educacionais que fornecem atividades interativas integradas a Sistemas de Gerenciamento de Cursos. O desenvolvimento de iMA, similarmente ao de outros sistemas criados em contexto de projetos acadêmicos, enfrenta problemas relacionados a manutenção e evolução de software, que afetam suas contribuições à sociedade. Isso é provocado principalmente pela degradação do código com o tempo e dos métodos ad-hoc utilizados, sem sistematização do processo ou procedimentos explícitos para prevenção desses problemas. Com o objetivo de aprimorar esse processo, esta dissertação apresenta uma Linha de Produto de Software (LPS) criada para o desenvolver iMA. O método usado para criá-la envolveu análise do domínio, formado pelos iMA existentes, a elaboração de um modelo de sistema para definir as responsabilidades das características obrigatórias, variantes e opcionais aos aplicativos, e a implementação de um arcabouço de aplicação. Assim, essa LPS consiste nesse arcabouço e seus manuais de funcionamento interno, utilização e evolução, promovendo reúso de código, arquitetura e processo. A avaliação deste trabalho foi conduzida com uma prova de conceito e um estudo de caso. A prova de conceito descreve o desenvolvimento de um novo iMA, chamado iTangran, apresentando a factibilidade da utilização da LPS para essa tarefa. O estudo de caso investigou com maior profundidade o impacto da LPS sobre a criação da nova versão de um aplicativo existente, chamado iVProg. Os resultados obtidos mostram que o oferecimento de um processo e uma arquitetura que guiam as tarefas do programador de iMA teve grande influência na sua percepção de produtividade e satisfação, além de contribuírem para a qualidade do código criado e sua documentação, fatores essenciais para a prevenção dos problemas de desenvolvimento enfrentados atualmente. / Educational software provide many benefits for teachers and students, from reducing repetitive tasks to offering assignments impossible with the use of only blackboard and paper. Interactive Learning Modules (iLM) are a family of educational systems which offer interactive assignments integrated with Learning Management Systems. The development of iLM, similarly to other software created in context of academic projects, faces issues related to software maintenance and evolution, which hinder their contributions to society. This is mainly caused by code degradation with time and to ad-hoc methods used, without a systematic process and explicit considerations to prevent these problems. With the goal of improving this process, this work presents a Software Product Line (SPL) for the development of iLM. The method used to create this SPL involved an analysis of the domain, which are the existing iLM, the creation of a system model in order to define the responsibilities of mandatory, variant and optional features among systems, and the implementation of an application framework. Therefore, the SPL consists of this framework and its manuals for internal operation, utilization and evolution, providing code, architecture and process reuse. Contributions of this work were evaluated by a proof of concept and a study case. The proof of concept describes the development of a new iLM called iTangran, presenting the possibility of using the SPL for this task. The study case investigated more deeply the SPL impact on the refactoring process of an existing iLM, iVProg. Results show that a guide and an architecture for the tasks undertaken by programmers have a significant influence on the perceived productivity and their satisfaction while working, also contributing to code and documentation quality, which are essential factors to prevent development problems such as those faced nowadays.
|
Page generated in 0.0221 seconds