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Dumas, Kuchling Janine. "1:1 Digital devices and preparatory school teachers’ classroom practices." Diss., University of Pretoria, 2020. http://hdl.handle.net/2263/80435.
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In this study, the influence of a 1:1 digital device on South African preparatory school teachers’ perceptions regarding their classroom practices is described. The focus is on the Chromebook as an ‘artifact’ of learning. Digital technology is becoming prevalent in all education spheres and, subsequently, interest in this topic is growing. In order to create an environment where optimal learning takes place, teachers and pupils should adapt their learning and teaching methods to embrace the effects of technology. Teachers are at the forefront of education and education trends involving digital devices are becoming a reality across all grades.
Qualitative research was conducted to gain insight into eight teachers’ perceptions on using a 1:1 digital device (the Chromebook) for teaching and learning in a private Gauteng school. The major findings were that teachers had to adapt their preparation, facilitation and assessment strategies to accommodate the use of the Chromebook in the classroom. This was mostly done successfully by the participants. The teachers realised that the Chromebook is a useful learning and teaching artifact or learning and teaching support material as a tool in the classroom. It enhances multimodal learning, encourages the inclusion of multiliteracies, and creates a third space of learning, where teachers and pupils cooperate in constructing new knowledge. A concern addressed by the teachers was that digital learning would have a negative impact on writing skills. They also stated that there should be a balance between technology and traditional teaching methods.
The most important recommendations are that teachers should change their attitude and their preparation and implementation of lessons when using the digital device in the classroom. Teachers should realise that pupils whose parents have the financial means and who have access to trending technology, today’s digital natives, have instant access to information and this has changed the way learning takes place. Although new to some teachers, the use of digital devices is second nature for many pupils of the 21st century. Teachers should embrace opportunities for professional development so that the digital device can be effectively incorporated in the learning process in the classroom.<br>Dissertation (MEd)--University of Pretoria 2020.<br>pt2021<br>Humanities Education<br>MEd<br>Unrestricted
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Hayashi, Takayuki. "A 1 V floating-point analog-to-digital converter for portable communication devices." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0005/MQ45436.pdf.
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RIZZO, LIGIA AMORIM. "DIGITAL TV IN MOBILE DEVICES: OPPORTUNITIES IN THE LOW INCOME COMSUMERS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2009. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=15719@1.
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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO<br>A televisão sempre ocupou um lugar relevante na vida cotidiana do
brasileiro, e novas possibilidades de consumo podem vir a influenciar o modo
como o telespectador se relaciona com conteúdo televisivo. A influência da
televisão na vida cotidiana do brasileiro e a difusão da telefonia celular nas
camadas de baixa renda criaram um cenário favorável para a introdução e
posterior adoção da TV portátil no celular, viabilizada pela implantação da
tecnologia de TV Digital no Brasil. A teoria do aprendizado por analogia foi
usada como arcabouço teórico para avaliar o processo de adoção dessa tecnologia,
que apesar de nova na forma de entrega (digital e móvel), já é bem conhecida e
considerada entre os brasileiros, tendo em vista a grande penetração do meio na
preferência popular. A contextualização do cenário passa, portanto, pelo
entendimento das dimensões, características e significados da TV na vida
cotidiana. A escolha pelo estudo das classes mais baixas se deve ao fato de que
estas se configuram como as maiores consumidoras de programação televisiva. O
resultado das pesquisas exploratórias revela um grande interesse em poder assistir
televisão em qualquer lugar, mesmo em movimento, o que pode indicar novas
oportunidades comerciais a partir dessa nova prática do consumo de mídia e
indica, ainda, que a força da presença da TV na vida cotidiana pode ser
significativa na intenção de adoção da TV portátil como uma alternativa para o
consumo de conteúdo televisivo em locais públicos.<br>Television has always had a relevant place in the Brazilian everyday life,
and new possibilities of consumption may influence the way viewers relate with
television content. The influence of television on the Brazilian everyday life and
the spreading of mobile telephony among the lower income classes have
established favorable conditions for the introduction and later adoption of portable
TV for mobile phones, which was made possible by the introduction of digital TV
technology in Brazil. The theory of learning by analogy was used as theoretical
basis to analyze the process of absorbing this technology, which, although new
from a delivery point of view, is already well known and considered by
Brazilians, as we can see when we consider its large stand in popular preference.
The contextualizing of the introduction conditions is thus tied to the
understanding of the dimensions, characteristics and meanings obtained by TV in
everyday life. The option for lower classes as an object of study stems from the
fact those classes represent the larger consumption of television programs. The
results of the exploratory research shows a great interest in watch TV anywhere,
even outside home. This may indicate new commercial opportunities based that
new form of media consumption. It also indicates that the weight of TV in
everyday life may be significant towards the intention of adopting the portable TV
as an alternative to TV content consumption in public places.
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LIMA, MAURO VIEIRA DE. "AGGREGATE INTERFERENCE FROM WHITE SPACE DEVICES IN DIGITAL TERRESTRIAL TELEVISION RECEIVERS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2017. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=31669@1.
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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO<br>COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR<br>PROGRAMA DE EXCELENCIA ACADEMICA<br>A tecnologia do rádio cognitivo tem sido pesquisada para utilização mais eficiente do espectro, pois permite o aproveitamento de faixas de frequência subutilizadas. Dispositivos rádio cognitivos que operam na banda de frequência da TV digital são conhecidos como White Space Devices (WSD) e utilizam canais livres sob a condição de não provocar interferência acima do limite estabelecido pelo órgão regulador. A autoridade reguladora do Reino Unido, Office of Communication (Ofcom), publicou, em fevereiro de 2015, a primeira regulação européia permitindo a operação de sistemas WSD na banda da TV digital através do suporte de sistemas de banco de dados geolocalizados. O regulamento Ofcom define uma metodologia para calcular a potência de transmissão máxima de um WSD através de um método de entrada única (single-entry) da interferência intersistema máxima. Devido a isso, a interferência agregada de WSDs co-canais que operam na mesma região pode ultrapassar a interferência intersistema máxima. Além deste problema, verifica-se que a metodologia Ofcom não define a interferência intersistema máxima pelo mesmo critério da interferência intrasistema como foi definida pelo planejamento do sistema primário de TV. Esta tese desenvolve uma nova metodologia de cálculo da potência de transmissão dos WSDs que soluciona os problemas identificados na metodologia Ofcom. A metodologia proposta garante a proteção do receptor de TV digital através de uma abordagem de múltiplas entradas da interferência dos WSDs e, adicionalmente,
aumenta a capacidade do sistema WSD quando comparada à metodologia Ofcom.<br>The technology of cognitive radio has been researched for more efficient use of spectrum, since it allows the use of under-utilized frequency bands. Cognitive radio devices operating in the digital TV frequency band are known as White Space Devices (WSD) and use free channels under the condition of not causing interference above the limit set by the regulator. The UK regulatory authority, Office of Communication (Ofcom), published in February 2015, the first European regulation allowing WSD systems in the digital TV band through the support of geo-database systems. The Ofcom regulation defines a methodology to calculate the maximum WSD transmission power through a single-entry method for the maximum intersystem interference. Due to this, the aggregate interference of cochannel WSDs operating in the same region may exceed this maximum intersystem interference. In addition to this problem, it is verified that the Ofcom methodology does not define maximum intersystem interference by the same criterion of intrasystem interference as was defined by the primary TV system planning. This thesis develops a new methodology for calculating the transmission power of WSDs that solves the problems identified in the
Ofcom methodology. The proposed methodology guarantees the protection of the digital TV receiver through a multiple-entry approach of the WSDs interference and, additionally, increases the WSD system capacity when compared to the Ofcom methodology.
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CARRION, PATRICIA TORRES PEREIRA. "THE RELATION OF VISUAL-DIGITAL LITERACY IN USER INTERACTION WITH MOBILE DEVICES." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2017. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=30700@1.
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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO<br>COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR<br>PROGRAMA DE SUPORTE À PÓS-GRADUAÇÃO DE INSTS. DE ENSINO<br>O ritmo acelerado de inovação tecnológica destaca as questões da relação entre usuários, objetos e ambientes digitais, e, evidencia, no contexto das interfaces gráficas, a existência de uma Alfabetização Visual-Digital. O meio digital, construído pela intersecção de diferentes mídias que misturam gêneros visuais distintos, exige dos usuários um conjunto específico de habilidades, uma vez que a instabilidade das interações digitais define uma dinâmica única entre designers, plataformas e usuários. Por isso, torna-se de extrema importância a investigação quanto às diferentes habilidades e processos de alfabetização desenvolvidos por usuários de tecnologia ao interagir na esfera digital. O objetivo desta pesquisa foi pesquisar o impacto da Alfabetização Visual, por meio da aquisição de repertórios, na experiência de usuários no acesso aos dispositivos móveis. Para tanto, trabalhou-se com a hipótese de que um repertório visual limitado é causa direta da ocorrência de uma Alfabetização Digital insuficiente para determinados usuários. Para uma base teórica, foram levantadas a evolução das tecnologias e das interfaces gráficas do usuário (GUIs); além de formalizados os conceitos de Alfabetização Visual e Digital. A partir desse levantamento, foram definidas duas técnicas de avaliação: um Teste de Compreensão Iconográfica e um Teste de Usabilidade. Os resultados finais de ambas as técnicas aplicadas mostraram que a Alfabetização Visual influencia, de fato, no desempenho dos usuários na interação com dispositivos, comprovando que a Alfabetização Digital se relaciona com os repertórios visuais dos indivíduos.<br>The rapid pace of technical innovation highlights the issues of the relationship between users, digital objects and environments, and, in the context of graphical interfaces, shows the existence of Visual-Digital Literacy. The digital medium, built by the intersection of different media that mix distinct visual genres, requires people to have a specific set of skills, since the instability of digital interactions defines a unique dynamic between designers, platforms and users. Hence, it becomes of the utmost importance to research on the different skills and processes of literacy developed by technology users when interacting in the digital sphere. This master s research proposes as an overall intention to investigate the impact of Visual Literacy, through the acquisition of repertoires, in users access to mobile devices. To that effect, the research hypothesis is that a limited visual repertoire is a direct cause of users deficiency in Digital Literacy skills. For a theoretical basis, the evolution of technologies and graphical user interfaces (GUIs) were raised; as well as outlined the concepts of Visual and Digital Literacy. Succeeding this review, two evaluation techniques were defined: an Iconographic Comprehension Test and a Usability Test. The final results of both applied techniques showed that Visual Literacy does influence on the performance of users in the interaction with devices, proving that Digital Literacy relates to people visual repertoires.
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Radaelli, Mara Regina Rosa. "APLICATIVOS EM DISPOSITIVOS MÓVEIS: UMA PROPOSTA INOVADORA DE LOUSA DIGITAL NA FORMAÇÃO DE PROFESSORES." Universidade Federal de Santa Maria, 2016. http://repositorio.ufsm.br/handle/1/10688.
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This research entitled "Applications in Mobile Devices: An Innovative Digital Lousa
Proposal in Teacher Training", developed in research line Educational Technology
Development Research Network, and in the Area of Concentration, Educational
Technologies in Network for Innovation and Democratization of Education in the
Master's degree in Educational Technology Network, in UFSM, focuses on the use of
applications on mobile devices in the classroom. Such mobile devices appear as the
most present contemporary technologies in everyday life and are used for many
different activities, both personal and professional ones or are applied to education.
In this approach, this research aimed to investigate the application possibilities of
using a tablet computer on a methodology of interactive whiteboard, with an
emphasis on interactivity, from training workshops for teachers from different areas of
knowledge and who operate in high schools, analyzing considerations, comments
and opinions of these teachers about the possibilities and uses of this proposal in
teaching practices in the classroom as a facilitating resource in the processes of
teaching and learning. Classified as a qualitative research, it was used as a
methodological approach to the action-research. As a final product of the research,
we have the methodological proposal for the use of interactive whiteboard from the
tablet and its applications, with the development of online tutorials. It was found that
the proposed methodology and the use of applications can enable contributions for
the teaching practice and also enable interactivity in teaching and learning
processes.<br>A presente pesquisa intitulada Aplicativos em Dispositivos Móveis: Uma Proposta
Inovadora de Lousa Digital na Formação de Professores , desenvolvida na linha de
pesquisa, Desenvolvimento de Tecnologias Educacionais em Rede e na Área de
Concentração, Tecnologias Educacionais em Rede para Inovação e Democratização
da Educação no curso de mestrado em Tecnologias Educacionais em Rede, na
UFSM, centra-se sobre o uso dos aplicativos em dispositivos móveis em sala de
aula. Os dispositivos móveis aparecem como as tecnologias contemporâneas mais
presentes no cotidiano, sendo utilizados para as mais diversas atividades e
aplicadas à educação. Nesse enfoque, a pesquisa teve como objetivo investigar as
possibilidades de uso, na educação, de aplicativos no tablet, inicialmente, em uma
proposta metodológica de lousa interativa, com ênfase na interatividade, a partir de
oficinas de formação para professores de diversas áreas de conhecimento que
atuam no ensino médio, analisando as considerações, observações e opiniões
destes professores quanto às possibilidades e uso desta proposta em práticas
docentes em sala de aula. Posteriormente, trabalhou-se nas possibilidades de
divulgação e distribuição das propostas desenvolvidas, utilizando o aplicativo
CODATA. Classificada como pesquisa qualitativa, utilizou-se como procedimento
metodológico a pesquisa-ação. Como produto final resultante da pesquisa, tem-se a
proposta metodológica interativa de lousa a partir do tablet e seus aplicativos,
apresentada nessa dissertação, bem como em tutorias online desenvolvidos ao
longo da pesquisa. Constatou-se que esta proposta metodológica com o uso de
aplicativos pode possibilitar contribuições para a formação dos professores e,
consequentemente, para sua prática docente ao inserir a interatividade nos
processos de ensino e de aprendizagem.
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Weizenmann, Carlos Eduardo. "ALFABETIZAÇÃO DIGITAL MEDIADA POR TABLETS PARA CRIANÇAS E ADOLESCENTES EM TRATAMENTO ONCOLÓGICO." Universidade Federal de Santa Maria, 2015. http://repositorio.ufsm.br/handle/1/10675.
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The use of mobile technologies becomes ever more present and necessary in our
lives, either for routine activities or education. Based on this argument, this dissertation aims
to analyze the possible contribution of using tablet as a tool to develop different
methodologies for digital literacy, thus providing inclusion in the "technological world". The
use of technological resources (tablet) has become a necessary tool to assist teaching and
learning process of children and adolescents. For this reason, it is important to conduct a
qualitative study using the method of action research by allowing greater involvement with its
object, through which the researcher is part of the field of research. We offered workshops
divided into two modules: the first one for free adaptation to the tablet and the second one for
using resources in various activities aiming at ludicity. The data collection system was carried
out in two stages: before the beginning of the workshops and at the end of module II. The
final product of this work was the creation of a virtual repository, of open access, that will be
inserted in the blog of the workshop so that there is greater awareness of the work
developed, which can be used by the students after the end of the workshops, facilitating
interaction, cooperation and collaboration among the group. The contributions of this work
aimed at the insertion of the mobile technologies to contribute to the participants medical
treatment. This study belongs to the research line: Desenvolvimento de Tecnologias
Educacionais em Rede, and the research project O uso de tecnologias móveis (tablets), no
processo de ensino e aprendizagem da alfabetização digital e língua espanhola, com
crianças e adolescentes em tratamento oncológico, approved in December 13, 2014, under
the number 912.827.<br>A utilização das tecnologias móveis se faz cada vez mais presente e necessária em
nossa vida, seja para as atividades rotineiras ou para a educação. Com base nesse
argumento, o objetivo aqui proposto é analisar as possíveis contribuições da utilização de
tablets como uma ferramenta que permite desenvolver diferentes metodologias para a
alfabetização digital, assim, proporcionando uma inclusão no mundo tecnológico . O uso
dos recursos tecnológicos (tablet) tornou-se uma ferramenta necessária para auxiliar o
ensino-aprendizagem de crianças e adolescentes. Por esse motivo, é importante a
realização de um estudo qualitativo utilizando o método de pesquisa-ação por permitir maior
envolvimento com o seu objeto, através do qual o pesquisador insere-se no campo da
pesquisa. Foram propostas oficinas divididas em dois módulos, sendo o primeiro deles de
adaptação livre ao tablet e o segundo, de utilização dos recursos na realização das
atividades diversas, visando a ludicidade. O sistema de coleta de dados foi realizado em
dois momentos: antes do início das oficinas e ao término do módulo II. O produto final deste
trabalho consistiu na criação de um repositório virtual, de livre acesso, que será inserido no
blog da oficina para que haja mais divulgação do trabalho desenvolvido, podendo ser
utilizado pelos alunos após o término das oficinas, facilitando a interação, cooperação e
colaboração entre o grupo. As contribuições deste trabalho visaram a inserção das
tecnologias móveis de modo a contribuir para seu tratamento médico. O presente estudo
pertence à linha de pesquisa Desenvolvimento de Tecnologias Educacionais em Rede e ao
projeto de pesquisa e tem por título O uso de tecnologias móveis (tablets), no processo de
ensino e aprendizagem da alfabetização digital e língua espanhola, com crianças e
adolescentes em tratamento oncológico, aprovado em 13 de dezembro de 2014, nº 912.827.
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Polonio, Dalle Christian Vinicius Coelho. "Uma proposta para o ensino de estática no ensino médio." Universidade Tecnológica Federal do Paraná, 2018. http://repositorio.utfpr.edu.br/jspui/handle/1/3089.
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Acompanha: Produto educacional: Uma proposta para o ensino de estática no ensino médio a partir de uma midia digital<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)<br>O presente estudo teve como objetivo produzir uma mídia digital sobre o conteúdo de estática com diferentes recursos a serem utilizados pelo professor de física, bem como, aplicar e verificar o potencial pedagógico dessa mídia, ou dos recursos presentes nessa mídia, junto a uma turma da primeira série do ensino médio de uma instituição pública da cidade de Paiçandu, Paraná. A mídia digital produzida se pautou em diferentes recursos de ensino, tais como: vídeos, simuladores e atividades práticas. Esse trabalho foi norteado pelos pressupostos da pesquisa qualitativa e, para se coletar os dados utilizou-se questionários estruturados, diário de bordo e todo material produzido pelos alunos durante o desenvolvimento das atividades. A aplicação das atividades da mídia ocorreram em quatro intervenções, totalizando oito horas no terceiro trimestre do ano letivo de 2017. Após análise e interpretação dos dados, a partir de pressupostos da Análise Textual Discursiva de Moraes e Galiazzi (2011), os resultados apontaram para uma evolução dos alunos com relação aos conceitos de estática abordados, bem como, para uma mudança de postura por parte dos alunos, principalmente aqueles que se faziam menos interessados nas aulas de Física.<br>The objective of this study was to produce a digital media about the static content with different resources to be used by the physics teacher, as well as to apply and verify the pedagogical potential of this media, or the resources present in this media, together with a first grade of a high school in a public institution in the city of Paiçandu, Paraná. The digital media produced was based on different teaching resources, such as videos, simulators and practical activities. This work was guided by the assumptions of the qualitative research and to collect the data was used structured questionnaires, logbook and all material produced by the students during the development of activities. The application of media activities occurred in four interventions, totaling eight hours in the third quarter of the 2017 school year. After analyzing and interpreting the data, based on the assumptions of the Discursive Textual Analysis of Moraes and Galiazzi (2011), the results pointed to an evolution of the students regarding concepts of static approach, as well as for a change of posture on the part of the students, mainly those that became less interested in the classes of Physics.
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Veiga, Ricardo Sales da. "Sistema de navegação e localização para um robô escalador magnético de inspeção baseado em sensores LIDAR." Universidade Tecnológica Federal do Paraná, 2015. http://repositorio.utfpr.edu.br/jspui/handle/1/1255.
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ANP; FINEP; MCT; CAPES<br>Este trabalho objetiva otimizar a localização de um robô móvel para a inspeção dos tanques de armazenamento de GLP -- Gás Liquefeito de Petróleo -- e permitir a navegação autônoma deste robô por toda a superfície do tanque. A falta de marcos no interior dos tanques levou ao desenvolvimento de uma solução envolvendo detecção de pequenas estruturas com sensores LIDAR (Light Detection and Ranging - Detecção e Telemetria por Luz) aplicada aos cordões de solda, estes sim presentes no interior do tanque, que é apresentada na primeira parte do trabalho. Em seguida, aplicando uma técnica de fusão de dados, as diferentes fontes de odometria presentes no robô são combinadas, permitindo uma precisão mais elevada na inspeção de modo geral. Por fim, o mapeamento e navegação simultâneos do exterior da esfera é abordado, a fim de se adicionar uma camada suplementar ao mapa digital, indicando os locais onde existem falhas. Testes para validação de cada uma das técnicas foram efetuados e uma análise de desempenho é apresentada ao final do trabalho.<br>This work aims to optimize localization of a climbing inspection robot for spherical LPG -- Liquified Petroleum Gas -- tanks and allow autonomous navigation along the entire surface of these tanks. One solution envolving small structures detection using LIDAR sensors is applied to the weld beads that are present inside the tanks. This solution is developed on the first part of this work. Following, a data fusion technique is used to combine the diferent odometry sources on the robot, resulting in a better, higher precision on the inspection as a whole. Finnaly, simultaneous mapping and navigation on the exterior of the spherical tank was studied in order to add one extra layer to the digital map, pinpointing the places where failures and weld beams were found. Validation tests for each one of this techniques are carried out and a performance analysis is also documented herein.
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Jokowiski, Graciela Johnsson Campos. "As janelas de David Hockney: os dispositivos móveis no processo de criação artística." Universidade Tecnológica Federal do Paraná, 2017. http://repositorio.utfpr.edu.br/jspui/handle/1/2593.
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Esta dissertação apresenta uma abordagem sobre os dispositivos móveis como possíveis mediadores do pensamento artístico. Fundamentada em conceitos teóricos que permeiam as relações entre arte, imagem e tecnologia, pretende compreender a participação destes dispositivos no processo de criação a partir da observação da arte visual de David Hockney nos celulares e tablets. Seus objetivos específicos abrangem estudos de como os artistas da arte contemporânea têm se expressado por meio das imagens e como as janelas digitais têm participado deste movimento. A dissertação se inicia com um estudo teórico sobre as janelas da arte, priorizando aquelas que se inserem na arte contemporânea, seguida por uma investigação da trajetória do artista David Hockney. A pesquisa teórica foi importante para o entendimento de como as artes visuais contemporâneas têm materializado os conceitos dos artistas. A arte de Hockney nos dispositivos móveis é analisada a partir da exposição da série de pinturas Flores Frescas, onde o artista expõe suas obras nos tablets e celulares. A análise das imagens de Hockney complementa a pesquisa por meio de uma observação qualitativa e interpretativa de seis obras da mesma série, fundamentada em parâmetros que a pesquisa teórica indicou como prioritários para a construção de uma estética da arte digital. Esta análise identificou tendências da criação artística incorporadas nas pinturas a partir dos dispositivos móveis. A conclusão mostra uma apropriação do dispositivo por este artista por meio de um processo criativo que colabora para a formação de uma estética contemporânea.<br>This research presents an approach on mobile devices as possible mediators of artistic thinking. Based on theoretical concepts about the relations between art, image and technology, it aims at understanding the participation of these devices in the process of creation from the observation of the visual art of David Hockney in the cellular phones and tablets. Its specific objectives are the studies of how artists of contemporary art have expressed themselves through images and how digital windows have participated in this movement. The research paper begins with a theoretical study on metaphorical windows in art, prioritizing those of contemporary art, and continues an investigation into the trajectory of the artist David Hockney. Theoretical research was important for the understanding of how visual arts materialize the concepts of contemporary artists. Hockney's art on mobile devices is analyzed from the Fresh Flowers painting exposition, in which the artist exposes his works on tablets and cell phones. The analysis of Hockney’s images complements the research through the observation of six paintings of the same series, based on parameters that the theoretical research indicated as important for the construction of an aesthetic of digital art. This analysis was important in identifying trends in artistic creation embodied in paintings for mobile devices. The conclusion shows an appropriation of the device by this artist through a painting that contributes to the formation of a contemporary aesthetic.
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Quadros, Thiago de. "Development and evaluation of an elderly fall detection system based on a wearable device located at wrist." Universidade Tecnológica Federal do Paraná, 2017. http://repositorio.utfpr.edu.br/jspui/handle/1/2619.
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A queda de idosos é um problema de saúde mundial. Todos os anos, cerca de 30% dos idosos com 65 anos ou mais são vítimas de quedas. Além disso, as consequências de uma queda podem ser fisiológicas (e.g. fraturas ósseas, ferimentos musculares) e psicológicas, como a perda de autoconfiança, levando a novas quedas. Uma solução para este problema está relacionada com ações preventivas (e.g. adaptação de mobília) aliadas a sistemas de detecção de quedas, os quais podem notificar familiares e serviços médicos de urgência. Como o tempo de espera por socorro após uma queda está relacionado com a severidade das consequências dela, esses sistemas devem oferecer elevada acurácia e detecção em tempo real. Embora existam várias soluções para isso na literatura (a maioria relacionada com dispositivos vestíveis), poucas delas estão relacionadas a dispositivos de punho, principalmente por causa dos desafios existentes para essa configuração. Considerando o punho como um local mais confortável, discreto e aceitável para uso de um dispositivo (menos associado com o estigma do uso de uma solução médica), este trabalho propõe o desenvolvimento e avaliação de uma solução baseada nessa configuração. Para isso, diferentes sensores (acelerômetro, giroscópio e magnetômetro) foram combinados com diferentes algoritmos, baseados em métodos de limiar e aprendizado de máquina, visando definir os melhores sinais e abordagem para a detecção de quedas. Esses métodos consideraram informações de aceleração, velocidade, deslocamento e orientação espacial, permitindo o cálculo de componentes verticais do movimento. Para o treino e avaliação dos algoritmos, dois protocolos diferentes foram empregados: um primeiro envolvendo 2 voluntários (homens, 27 e 31 anos) simulando um total de 80 sinais de queda e 80 de não-queda, e um segundo envolvendo 22 voluntários (14/8 homens/mulheres, idade média: 25,2 ± 4,7) simulando um total de 396 sinais de queda e 396 de não-queda. Uma análise exaustiva de diferentes sinais e parâmetros de configuração foi executada para cada método. O melhor algoritmo baseado em limiar considerou sinais de aceleração vertical e velocidade total, alcançando 95,8% de sensibilidade e 86,5% de especificidade. Por outro lado, o melhor algoritmo de aprendizagem de máquina foi o baseado no método K-Nearest Neighbors, considerando informações de aceleração, velocidade e deslocamento verticais combinadas com os ângulos de orientação espacial: 100% de sensibilidade e 97,9% de especificidade. Os resultados obtidos permitem enfatizar a relevância de algoritmos de aprendizagem de máquina para sistemas de detecção de queda vestíveis localizados no punho quando comparados a algoritmos baseados em limiar. Esta conclusão oferece grande contribuição para a pesquisa de detectores de quedas similares, sugerindo a melhor abordagem para novos desenvolvimentos.<br>Falls in the elderly age are a world health problem. Every year, about 30% of people aged 65 or older become victims of fall events. The consequences of a fall may be physiological (e.g. bone fractures, muscular injuries) and psychological, including the loss of self-confidence by fear of falling, which leads to new falls. A solution to this problem is related to preventive actions (e.g. adapting furniture) allied to fall detection systems, which can alert family members and emergency medical services. Since the response time for help is related to the fall's consequences and severity, such systems must offer high accuracy and real-time fall detection. Although there are many fall detection solutions in literature (most part of them related to wearable devices), few of them are related to wrist-worn devices, mainly because of the existing challenges for this configuration. Considering the wrist as a comfortable, discrete and acceptable place for an elderly wearable device (less associated to the stigma of using a medical device), this work proposes the development and evaluation of a fall detection solution based on this configuration. For this, different sensors (accelerometer, gyroscope and magnetometer) were combined to different algorithms, based on threshold and machine learning methods, in order to define the best signals and approach for an elderly fall detection. These methods considered acceleration, velocity and displacement information, relating them with wrist spatial orientation, allowing the calculation of the vertical components of each movement. For the algorithms' training and evaluation, two different protocols were employed: one involving 2 volunteers (both males, ages of 27 and 31) performing a total of 80 fall and 80 non-fall events simulation, and the other involving 22 volunteers (14/8 males/females, ages mean: 25.2 ± 4.7) performing a total of 396 fall and 396 non-fall events simulation. An exhaustive evaluation of different signals and configuration parameters was performed for each method. The best threshold-based algorithm employed the vertical acceleration and total velocity signals, achieving 95.8% and 86.5% of sensitivity and specificity, respectively. On the other hand, the best machine learning algorithm was based on the K-Nearest Neighbors method employing the vertical acceleration, velocity and displacement information combined with spatial orientation angles: 100% of sensitivity and 97.9% of specificity. The obtained results allow to emphasize the relevance of machine learning algorithms for wrist-worn fall detection systems instead of traditional threshold-based algorithms. These results offer great contributions for the research of similar wearable fall detectors, suggesting the best approach for new developments.
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Carvalho, Tatiana Maria Couto. "Objetos de aprendizagem digitais: uma análise sobre a sua pertinência pedagógica para o ensino e aprendizagem de língua espanhola." Universidade Tecnológica Federal do Paraná, 2017. http://repositorio.utfpr.edu.br/jspui/handle/1/2708.
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O aumento no uso dos recursos tecnológicos no ambiente escolar, especificamente nas aulas de línguas estrangeiras, revela a importância de uma discussão sobre o tema e a necessidade de uma análise consistente sobre os materiais digitais utilizados com propósito educativo. Considerando a relevância global da língua espanhola e a importância estratégica que seu estudo representa para o Brasil, esta pesquisa objetiva analisar a pertinência pedagógica dos objetos de aprendizagem digitais disponíveis para o ensino e aprendizagem da língua espanhola, fundamentando-se nos documentos oficiais para a educação brasileira. A partir de um estudo bibliográfico e de uma abordagem qualitativa e metodologia exploratória (MINAYO, 2009), (CHIZZOTI, 2010), a pesquisa foi desenvolvida a partir de uma concepção discursiva de língua (BAKHTIN, 2002) e um entendimento sociointeracionista de ensino (VYGOTSKY, 1993). Estudos teóricos sobre tecnologia e sua relação com a educação (PINTO, 2005), (FEENBERG, 2016) precederam a investigação sobre a conceitualização e os entendimentos em relação a objetos de aprendizagem (LEFFA, 2006). Buscou-se em repositórios nacionais gratuitos objetos de aprendizagem de língua espanhola que atendessem ao critério estabelecido pela pesquisa de oferecer interatividade aos usuários. Apenas cinco exemplares correspondiam ao critério e todos foram avaliados segundo suas características de identificação, conteúdo, aspectos didáticos e usabilidade. Os resultados parciais obtidos apontam no sentido de que a área carece de estudos teóricos e de objetos de aprendizagem de qualidade, concernentes com teorias de aquisição de língua estrangeira e métodos de ensino e aprendizagem empregados atualmente e recomendados pelos documentos oficiais que norteiam a educação no país.<br>El incremento en el uso de los recursos tecnológicos en el ambiente escolar, específicamente en las clases de lenguas extranjeras, revela la importancia de una discusión sobre el tema y la necesidad de un análisis consistente sobre los materiales digitales utilizados con propósito educativo. Considerando la relevancia global de la lengua española y la importancia estratégica que su estudio representa para Brasil, esta investigación objetiva analizar la pertinencia pedagógica de los objetos de aprendizaje digitales disponibles para la enseñanza y aprendizaje de la lengua española, fundamentándose en los documentos oficiales para la educación brasileña. A partir de un estudio bibliográfico y de un abordaje cualitativo y metodología exploratoria (MINAYO, 2009), (CHIZZOTI, 2010), la investigación ha sido desarrollada a partir de una concepción discursiva de lengua (BAKHTIN, 2002) y un entendimiento sociointeracionista de enseñanza (VYGOTSKY, 1993). Estudios teóricos sobre tecnología y su relación con la educación (PINTO, 2005), (FEENBERG, 2016) precedieron la investigación sobre la conceptualización y los entendimientos en relación a objetos de aprendizaje (LEFFA, 2006). Se buscó en repositorios nacionales gratuitos objetos de aprendizaje de lengua española que atendiesen al criterio establecido por la investigación de ofrecer interactividad a los usuarios. Solamente cinco ejemplares correspondieron al criterio y todos han sido evaluados según sus características de identificación, contenido, aspectos didácticos y usabilidad. Los resultados obtenidos apuntan en el sentido de que el área carece de estudios teóricos y de objetos de aprendizaje de calidad, concernientes con teorías de adquisición de lengua extranjera y métodos de enseñanza y aprendizaje empleados actualmente y recomendados por los documentos oficiales que nortean la educación en el país.
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Hynčicová, Tereza. "Plánování a analýza pohybu zařízení pro absolutní kalibraci GNSS antén." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2014. http://www.nusl.cz/ntk/nusl-227138.
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The thesis is aimed at movement analysis and planning of a robotic device for absolute GNSS antenna calibration, which is developed at Brno University of Technology, Faculty of Civil Engineering, Institute of Geodesy. The first section is devoted to independent verification of the temporal synchronization of the robotic device’s movement, which is a prerequisite for the successful antenna calibration. The following section is focused on analysis of moveable characteristics since their knowledge is crucial for the following movement planning. Method of the device’s movement shooting by camera and evaluation its position based on gained photographs is used for both testing measurements. The final part is dedicated to movement planning, especially to calibrated antenna weighting influence on device’s movement characteristics, test results implementation into the observation program and arm movement planning considering the homogeneous calibration measurement layout.
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Nishibe, Caio Arce. "Central de confrontos para um sistema automático de identificação biométrica: uma abordagem de implementação escalável." Universidade Tecnológica Federal do Paraná, 2017. http://repositorio.utfpr.edu.br/jspui/handle/1/3142.
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Com a popularização do uso da biometria, determinar a identidade de um indivíduo é uma atividade cada vez mais comum em diversos contextos: controle de acesso físico e lógico, controle de fronteiras, identificações criminais e forenses, pagamentos. Sendo assim, existe uma demanda crescente por Sistemas Automáticos de Identificação Biométrica (ABIS) cada vez mais rápidos, com elevada acurácia e que possam operar com um grande volume de dados. Este trabalho apresenta uma abordagem de implementação de uma central de confrontos para um ABIS de grande escala utilizando um framework de computação em memória. Foram realizados experimentos em uma base de dados real com mais de 50 milhões de impressões digitais em um cluster com até 16 nós. Os resultados mostraram a escalabilidade da solução proposta e a capacidade de operar em grandes bases de dados.<br>With the popularization of biometrics, personal identification is an increasingly common activity in several contexts: physical and logical access control, border control, criminal and forensic identification, payments. Thus, there is a growing demand for faster and accurate Automatic Biometric Identification Systems (ABIS) capable to handle a large volume of biometric data. This work presents an approach to implement a scalable cluster-based matching platform for a large-scale ABIS using an in-memory computing framework. We have conducted some experiments that involved a database with more than 50 million captured fingerprints, in a cluster up to 16 nodes. The results have shown the scalability of the proposed solution and the capability to handle a large biometric database.
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Hoffmann, Daniela Stevanin. "Modalidade 1:1 : tecnologia individual possibilitando redes de fluência digital." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2011. http://hdl.handle.net/10183/34145.
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Alunos, professores, gestores, pesquisadores universitários, objetos tecnológicos, arquivos, registros, habilidades, ... são os nós que compõem a grande rede tecida na experiência piloto do Projeto Um Computador por Aluno na Escola Estadual de Ensino Fundamental Luciana de Abreu de Porto Alegre no Rio Grande do Sul onde foi desenvolvida a presente pesquisa. O problema central desta investigação é compreender como se dá a constituição de uma Rede de Fluência Digital a partir do trabalho com Projetos de Aprendizagem mediado pela tecnologia individualmente disponível na modalidade 1:1. A fim de identificar as relações entre a implementação da proposta pedagógica e a prática da modalidade 1:1 na escola, foram definidas três redes: a Rede de Atores, formada pela comunidade da escola Luciana de Abreu e pesquisadores do Laboratório de Estudos Cognitivos da Universidade Federal do Rio Grande do Sul (LEC), atuando em uma pesquisa-ação; a Rede de Recursos, composta pelo laptop educacional XO e o ambiente virtual de aprendizagem AMADIS; e a Rede de Fluência Digital, resultado da interação entre estas redes. A abordagem teórico-metodológica que subsidia a elaboração do problema e a análise dos dados é a Epistemologia Genética. Desenvolveu-se um estudo de caso cuja unidade de análise foi a Rede de Atores que apresentou como evidências os arquivos dos laptops e os registros do histórico do ambiente virtual de um grupo de dez alunos da Rede de Atores e o diário de campo da observação participante da pesquisadora do LEC, autora desta investigação. Foram elaborados, a partir das evidências, Identificadores e Períodos Singulares da Rede de Fluência Digital, que auxiliaram na Identificação de peculiaridades e na Caracterização dos períodos singulares na constituição da Rede de Fluência Digital. Estabelecendo relações entre o conceito de Fluência Digital de Ba, Tally & Tsikalas (2002) e estas duas etapas da análise foram criadas as Categorias da Rede de Fluência Digital que permitiram, com o processo de Categorização da constituição da Rede de Fluência Digital, compreender que a Rede de Fluência Digital se deu pelo desenvolvimento de condutas cognitivas constituídas de meios elaborados pelos sujeitos da Rede de Atores para solucionar os problemas com os quais se deparavam quando em interação com a Rede de Recursos. Entende-se que este trabalho contribui para a área da Informática Educativa nos estudos relacionados à implementação da modalidade 1:1 nas escolas, à fluência digital, à vinculação entre prática pedagógica e Tecnologias da Informação e Comunicação e a teorizações sobre possíveis relações entre estas e a Epistemologia Genética. Propõe-se dar continuidade a investigações relacionadas à modalidade 1:1 voltadas à formação de professores.<br>Students, teachers, administrators, university researchers, technological objects, files, records, abilities, ... these are the nodes that compose the big network built in the experience of Projeto Um Computador por Aluno in Escola Estadual de Ensino Fundamental Luciana de Abreu from Porto Alegre in Rio Grande do Sul/Brasil, where this research was developed. The central problem of this research is to comprehend how is the establishment of a Network of Digital Fluency from work with Learning Projects mediated by individually available technology in 1:1 mode. Three networks were defined in order to identify the relations between the implementation of pedagogical proposal and the practice of 1:1 mode in school: the Network of Actors, composed by Luciana de Abreu’s school community and researchers from Laboratório de Estudos Cognitivos da Universidade Federal do Rio Grande do Sul (LEC), operating on an action research; the Network of Resources, comprised of the XO laptop and the virtual learning environment AMADIS; and the Network of Digital Fluency, the result from the interaction between these networks. The theoretical and methodological approach that corroborates the formulation of problem and the data analysis is the Genetic Epistemology. A case study was developed. Its unit of analysis was the Network of Actors that had presented as evidences the laptops files and the history records of the virtual environment of a group of ten students from the Network of Actors and the notes from the diary of the participant observation of the LEC’ researcher, author of this research. Identifiers and Singular periods of Network of Digital Fluency were developed based on the evidences. They were used in Identification of peculiarities and in Characterization of singular periods in Network of Digital Fluency constitution. The establishment of relations between the concept of Digital Fluency Ba, Tally & Tsikalas (2002) and these two steps of the analysis led to the creation of the Categories of Network of Digital Fluency that, by the Categorization of Network of Digital Fluency constitution, allowed to understand that the Network of Digital Fluency happened by the development of cognitive behavior constituted by the means elaborated by the subject of the Network of Actors to solve problems which were faced while interacting with the Network of Resources. It is understood that this doctoral thesis contributes to the area of Computers in Education in studies related to implementation of 1:1 mode in schools, digital fluency, linkage between pedagogical practice and Technologies of Information and Communication and theorizing about possible relationships between these and Genetic Epistemology. It is proposed to continue investigations related to the 1:1 mode focused on teacher training.<br>Alumnos, profesores, gestores, investigadores universitarios, objetos tecnológicos, ficheros, registros, habilidades, ... son los nodos que hacen parte de la gran red tejida en la experiencia prototipa del Projeto Um Computador por Aluno en la Escola Estadual de Ensino Fundamental Luciana de Abreu en Porto Alegre en el Estado Rio Grande do Sul/Brasil donde fue desarrollada la presente investigación. Su problema central es comprender como ocurre la constitución de una Red de Fluidez Digital a partir del trabajo con Proyectos de Aprendizaje mediado por la tecnología individualmente disponible en la modalidad 1:1. Con el fin de identificar las relaciones entre la puesta en marcha de la propuesta pedagógica y la práctica de la modalidad 1:1 en la escuela, fueron definidas tres redes: la Red de Actores, constituida por la comunidad de la Escola Luciana de Abreu e investigadores del Laboratório de Estudos Cognitivos da Universidade Federal do Rio Grande do Sul (LEC), actuando en una investigación acción; la Red de Recursos, compuesta por el laptop educativo XO y el ambiente virtual de aprendizaje AMADIS; e a Rede de Fluidez Digital, resultado de la interacción de estas redes. El abordaje teórico metodológico que basa la elaboración del problema y el análisis de los datos es la Epistemología Genética. Se desarrolló un estudio de caso cuya unidad de análisis fue la Red de Actores que presentó como pruebas los ficheros de los laptops y los registros del historial del ambiente virtual de un grupo de diez alumnos de la Red de Actores y las notas de la investigadora del LEC, autora de esta investigación. A partir das pruebas fueron elaborados Identificadores y Períodos singulares de la Rede de Fluidez Digital que auxiliaron en la Identificación de peculiaridad y en la Caracterización de los Períodos Singulares en la constitución de la Rede de Fluidez Digital. Estableciendo relaciones entre el concepto de Fluidez Digital de Ba, Tally & Tsikalas (2002) y estas dos etapas del análisis fueron organizadas las Categorías de la Rede de Fluidez Digital que permitieron, con el proceso de Categorización de la constitución de la Rede de Fluidez Digital, comprender que la Red de Fluidez Digital se hizo por el desarrollo de conductas cognitivas constituidas de medios elaborados por los individuos de la Red de Actores para resolver los problemas con que se presentaron cuando interactuaban con la Red de Recursos. Se comprende que esta tesis doctoral contribuye para el área de la Informática Educativa en los estudios relacionados a la implementación de la modalidad 1:1 en las escuelas, a la fluidez digital, a la vinculación entre la práctica pedagógica y las Tecnologías da Información y Comunicación y las teorías sobre posibles relaciones entre estas y la Epistemología Genética. Se propone seguir con investigaciones relacionadas a la modalidad 1:1 que estén volcadas a la formación de profesores.
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Therriault, Victoria. "Exploring Factors Related to Acceptance of 1|1 Devices among High School Students." Thesis, Northern Illinois University, 2019. http://pqdtopen.proquest.com/#viewpdf?dispub=10977175.
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<p> Studies show that students in lower socioeconomic status (SES) districts tend to have fewer resources, and in turn have greater achievement gaps than their affluent peers from neighboring districts. In an effort to bridge these gaps, schools have turned to 1:1 computing to bring electronic resources to their students that they might not have otherwise. However, to date there are minimal studies indicating whether or not high school students are willing to accept technology for classroom instructional purposes. This study examined the extent to which student demographic characteristics (e.g., sex, race/ethnicity, SES) are related to their acceptance of Chromebook use for instructional purposes during the initial implementation of a 1:1 initiative using framework of the Unified Theory of Acceptance and Use of Technology (UTAUT) model. This study used quantitative correlational methods, using data from a survey that was administered to 171 public high school students in the Midwest region of the United States. Results indicated that the UTAUT model was upheld. Effort expectancy (EE) and performance expectancy (PE) positively predicted behavioral intention (BI), and race/ethnicity also had a relationship with BI. This study also found statistically significant interaction effects for experience × PE as well as gender × EE. Additionally, this study found that while including SES as a moderating effect did not result in statistically significant effects, the inclusion of the PE × SES and EE × SES interaction effect in the model resulted in a statistically significant relationship between race/ethnicity and BI.</p><p>
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Sádaba, Teresa. "Moda en el entorno digital [Capítulo 1]." Universidad Peruana de Ciencias Aplicadas (UPC), 2020. http://hdl.handle.net/10757/652852.
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Desde hace varios años se habla de adaptarse al entorno digital, pero ¿cómo hacerlo con éxito y a partir de la moda? La respuesta la tiene este libro, Moda en el entorno digital, que presenta diversos casos y perspectivas que nos ayudarán a comprender la relación que debe tener la moda, la comunicación y el negocio para poder triunfar en el mundo actual. La publicación cuenta con entrevistas, datos cuantitativos y análisis de campo que proponen conocer el negocio de la moda y nos ofrece las claves necesarias para conocer lo que son los e-commerce, la omnicanalidad, el consumidor digital, el sector de lujo, los fashion influentials, la mediatización de la moda, la tienda, el storytellig para las marcas y hasta los fashion films. Se trata de una mirada al ecosistema empresarial europeo que nos servirá de punto de partida para empezar a ver la moda con una mirada de transformación y contemporaneidad.
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Kaube, Benjamin. "Plasmonics : from electrons to devices." Thesis, Imperial College London, 2017. http://hdl.handle.net/10044/1/58997.
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From molecular sensors to perfect lenses, plasmonic devices promise a wealth of breakthrough applications by coupling light to oscillations of the electron plasma. In order to harness the full technological potential of plasmonics, coherent plasma excitations must be sustained over many cycles. On the scale of practical devices, optical properties of media are characterised by the mascroscopic dielectric function. This quantity can be determined from first principles in terms of transitions between electronic states. Understanding of losses within plasmonic systems must thus be built up from electrons to devices -- the approach taken in this thesis. Optical losses are explored with application to prototypical plasmonic systems, noble metals copper, silver and gold. Density functional theory with quasiparticle self-consistent GW (QSGW) corrections are employed in order to build up an accurate description of the electronic states. Interband dielectric functions are consequently obtained within the linear response formalism, finding good agreement with experimental literature. Electron interactions with lattice vibrations are found to be an essential feature in describing optical losses at low energies (also known as Drude losses). Electron-phonon interactions are included by two approaches: many body perturbation theory via the phonon contribution to the self energy and the semi-classical Williams Lax averages over nuclear displacements. The latter approach was used to determine the temperature dependence of silver optical spectra and constants from first principles, achieving agreement with experiment. Lastly, first principles calculations of silver nanodots are presented.
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Briscoe, Gerard. "Digital ecosystems." Thesis, Imperial College London, 2009. http://hdl.handle.net/10044/1/6158.
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We view Digital Ecosystems to be the digital counterparts of biological ecosystems, which are considered to be robust, self-organising and scalable architectures that can automatically solve complex, dynamic problems. So, this work is concerned with the creation, investigation, and optimisation of Digital Ecosystems, exploiting the self-organising properties of biological ecosystems. First, we created the Digital Ecosystem, a novel optimisation technique inspired by biological ecosystems, where the optimisation works at two levels: a first optimisation, migration of agents which are distributed in a decentralised peer-to-peer network, operating continuously in time; this process feeds a second optimisation based on evolutionary computing that operates locally on single peers and is aimed at finding solutions to satisfy locally relevant constraints. We then investigated its self-organising aspects, starting with an extension to the definition of Physical Complexity to include the evolving agent populations of our Digital Ecosystem. Next, we established stability of evolving agent populations over time, by extending the Chli-DeWilde definition of agent stability to include evolutionary dynamics. Further, we evaluated the diversity of the software agents within evolving agent populations, relative to the environment provided by the user base. To conclude, we considered alternative augmentations to optimise and accelerate our Digital Ecosystem, by studying the accelerating effect of a clustering catalyst on the evolutionary dynamics of our Digital Ecosystem, through the direct acceleration of the evolutionary processes. We also studied the optimising effect of targeted migration on the ecological dynamics of our Digital Ecosystem, through the indirect and emergent optimisation of the agent migration patterns. Overall, we have advanced the understanding of creating Digital Ecosystems, the self-organisation that occurs within them, and the optimisation of their Ecosystem-Oriented Architecture.
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Herrera-Marti, David A. "Implementations of fault-tolerant quantum devices." Thesis, Imperial College London, 2012. http://hdl.handle.net/10044/1/10209.
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Accurate control and addressability of quantum devices will come with the promise of improvement in a wide variety of theoretical and applied fields, such as chemistry, condensed matter physics, theoretical computer science, foundational physics, communications, metrology and others. Decoherence of quantum states and the loss of quantum systems have adverse effects and deter a satisfactory usage of quantum devices. This is the main problem to be overcome, which is the goal of quantum fault tolerance. In this thesis we present a series of works that contribute to some of the fields mentioned above, in the direction of fighting decoherence and loss. These works fall in two categories: on one hand, we looked at computer architectures which can be used to combat errors, using techniques of quantum error correcting codes. In a first project we found decoherence and loss probability thresholds below which quantum computing is provably possible. We assumed a very particular error model tailored specially to quantum dots as single photon sources and linear optics. Subsequently we looked at the problem of loss, both of heralded and unheralded, and devised some ways to fight it. The framework under which this work was done was used to develop theory which is currently being tested in a quantum optics experimental group and will be reported in an article later this year. On the other hand, we studied how the error probability can be reduced at the physical level, thanks exclusively to the properties of the system in which information is stored, as opposed to making use of quantum codes. We looked at a particular superconducting circuit, which is potentially very well protected against some types of decoherence. In particular, we observed that the interaction with the environment become weaker for certain values of the circuit external parameters.
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Logan, Stephen Alister. "Respiratory heat transfer devices for divers." Thesis, Imperial College London, 1990. http://hdl.handle.net/10044/1/46414.
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Werngren, Jan. "1-till-1* och lärares kompetensutveckling (*en dator per elev) : En fallstudie av fyra lärares kompetensutveckling i samband med en kommunal 1-till-1-satsning." Thesis, Högskolan i Halmstad, Akademin för lärande, humaniora och samhälle, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-29696.
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Den föreliggande studien är en kvalitativ fallstudie med syftet att undersöka lärares kompetensutveckling i samband med 1-till-1-satsningar (en dator per elev). Studiens frågeställning kretsar kring följande två frågor; Hur har lärarna uppfattat kompetensutvecklingen de erhållit i samband med kommunens 1-till-1-satsning? Hur har lärarnas kompetensutveckling i användandet av nya läroverktyg (MacBook Air) påverkat lärarnas didaktiska tillvägagångssätt? Höstterminen 2012 påbörjades en sådan 1-till-1-satsning i en av norra skånes kommuner. Baserat utifrån ett fenomenologiskt perspektiv kunde studien ge information kring lärarnas upplevda erfarenheter och belysa problematiken kring 1-till-1.
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Khan, K. R. "Digital generator protection." Thesis, Imperial College London, 1985. http://hdl.handle.net/10044/1/37743.
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Hallman, Emil, and Magnus Haglund. "Digitaliseringen av undervisningen : En forskningsöversikt över effekterna av digitaliseringskoncepten 1:1 och ASL." Thesis, Linköpings universitet, Institutionen för samhälls- och välfärdsstudier, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-137472.
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Denna forskningsöversikt behandlar digitaliseringen av undervisningen utifrån koncepten 1:1 (en dator per elev) och ASL (att skriva sig till läsning). Vi har via databassökning och manuell sökning tagit del av relevant litteratur som vi sedan gjort en kvalitativ innehållsanalys på. Vi behandlar vilka effekter koncepten enligt forskningen har för elever och lärare. Det råder ingen allmän konsensus om detta, då forskningsresultat pekar mot både positiva och negativa effekter. Vi söker därför även i litteraturen efter faktorer som visat sig gynna goda resultat. De faktorer vi funnit är struktur av fortbildning och stöd, av både teknisk och didaktisk karaktär, samt ett sociokulturellt arbetssätt.Genomgående i den litteratur vi läst efterfrågas mer forskning på området. Detta inkluderar både kritisk granskning av den forskning som nu finns och ny forskning som tar hänsyn till fler aspekter av de begrepp som berörs och som innefattar en vidgad kunskapssyn.
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Siebörger, David Robert. "Multiprotocol control of networked home entertainment devices." Thesis, Rhodes University, 2004. http://eprints.ru.ac.za/47/1/thesis.pdf.
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Networks will soon connect a wide range of computing devices within the home. Amongst those devices will be home entertainment devices. Remote control over the network will be a key application for networked entertainment devices, and requires a protocol for communication understood by both controller and controlled device. Devices capable of communication using multiple control protocols will be compatible with a wider range of controllers than those which implement only one control protocol. This work examines home networks and a number of control protocols. The implementations of the UPnP and AV/C protocols for an AV receiver are described. The issues involved in the concurrent use of multiple control protocols to control a device are considered, possible methods of concurrent control discussed, and a solution which simulates virtual copies of the device is implemented and tested.
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Pagiatakis, Gerasimos. "Finite element analysis of optical waveguide devices." Thesis, Imperial College London, 1990. http://hdl.handle.net/10044/1/46484.
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Boonkoom, Thitikorn. "InP quantum dots for hybrid photovoltaic devices." Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/17778.
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Significant research efforts have been directed towards the development of solar cells comprising blends of conjugated polymers and II-VI inorganic semiconductors (e.g. CdSe and CdS). Despite recent advances in the power conversion efficiency of such devices, the toxicity of Cd-based materials remains a concern with regard to widespread implementation. This thesis focuses on alternative (lower toxicity) InP nanocrystals for use as electron acceptors and light-harvesting materials in solution-processed polymer solar cells. In this thesis a combination of novel materials design/processing, transient absorption spectroscopy (TAS) and time-resolved photoluminescence spectroscopy (TRPL) is used to study the charge generation in InP:polymer photoactive layers. These studies are complimented by morphological characterisation of the photoactive layers as well as device studies. One aim of this thesis is the elucidation of quantitative structure function relationships that can be used to guide the design of new hybrid nanocomposite materials for photovoltaic devices. As such the data presented in this thesis helps to advance the present day understanding how hybrid solar cells work. The first chapter focuses on the synthesis of InP quantum dots (QDs) using an organometallic reaction. The aim of the work in this chapter was to prepare InP QDs with a size that provides an appropriate energy offset relative to the selected the electron donating polymer, poly(3-hexylthiophene) (P3HT). Detailed studies on the growth of InP QDs and how the reaction conditions affect the particle size are provided. The process of ligand exchange from hexadecylamine (HDA) to pyridine prior to blending with P3HT is also described. The second chapter focuses on charge transfer between the P3HT and the InP QDs which is a key process for achieving efficient photovoltaic device operation. Steady state and time-resolved photoluminescence and absorption spectroscopy were used to better understand the parameters influencing charge separation. After the blending and annealing conditions had been optimised to maximise the yield of photogenerated charges, the P3HT:InP blend was found to provide approximately twice yield of standard P3HT:PCBM blends. In addition, the decay lifetime of the polaron in P3HT:InP was found to be longer than that of P3HT:PCBM, suggesting the P3HT:InP blend is a promising active layer material for hybrid solar cells. The third chapter focuses on the fabrication and characterisation of hybrid solar cells. The fabrication conditions were optimised before carrying out detailed studies on the effect of thermal annealing. Although the device performance improved significantly with increasing annealing temperature, the net photocurrent was found to be low, compared to standard P3HT:PCBM devices, suggesting poor charge transport within the device. Nevertheless, if the charge transport can be improved, P3HT:InP still has potential to provide efficient hybrid solar cells. The last result chapter focuses on preliminary studies of quantum dot based light emitting diodes (QDLEDs) using InP QDs as light emitters. ZnO was used as electron transporting and hole blocking layer and poly(9,9-dioctylfluorene) (PFO) as a host medium and a hole transporting layer. The device structure and the PFO:InP blend composition were investigated to obtain QDLEDs with electroluminescence from the InP quantum dots. The findings suggest that ZnO plays a key role in suppressing the electroluminescence of PFO, most likely due to the hole blocking effect of the ZnO layer. Despite the low efficiencies of the InP-based QDLEDs, the results suggest that InP QDs are potential candidates for emitters in QDLEDs.
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Javaid, Atif. "Structural polymer composites for energy storage devices." Thesis, Imperial College London, 2012. http://hdl.handle.net/10044/1/9464.
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Multifunctional composites have attracted a great deal of attention as they offer a way to cut down the parasitic weight in vehicles which not only reduces the operational costs but also reduces the fuel consumption in vehicles. Current engineering design is increasingly sophisticated, requiring more efficient material utilisation; sub-system mass and volume are crucial application determinants. This dissertation contributes to the fabrication of composites that can store electrical energy and are known as structural supercapacitors. The key in the fabrication of structural supercapacitors was not simply to bind two disparate components together, but to produce a single coherent material that inherently performed both roles of a structural composite and a supercapacitor. This design approach is at a relatively early stage, and faces significant design and material synthesis challenges. Disparate material requirements, such as structural and electrochemical properties, have to be engineered and optimised simultaneously. This study investigates on structural supercapacitors fabricated by using as-received as well as activated carbon fibre cloths as reinforcement and electrodes; multifunctional resin as electrolyte and matrix; and glass fibre cloths, filter papers or polymer membranes as insulators. Such a system should deliver electrical energy storage capacity as well as bear mechanical loads. Different liquid electrolytes, such as ionic liquids and salts based on Li+ and NH4+, were studied in order to optimise the multifunctionality of polymer electrolyte. Mesoporous silica particles were also introduced into polymer electrolytes in order to enhance the mechanical and electrochemical performance of polymer electrolytes. Nanostructured/ multifunctional resin blends were cured in cylindrical form and were examined by compression testing as well as impedance spectroscopy. An ionic conductivity of 0.8 mS/cm and a compression modulus of 62 MPa have been synthesised for the polymer electrolyte in the current study. By varying the separators, multifunctional resins and the electrodes, different structural supercapacitor configurations were manufactured using a resin infusion under flexible tooling (RIFT) method and were characterised to study the electrochemical performance by using charge/discharge method and mechanical performance by using ±45° laminate shear testing. The improved structural supercapacitors showed an energy density of 0.1 Wh/kg, a power density of 36 W/kg and a shear modulus of 1.7 GPa.
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Fletcher, R. G. "Power semiconductor devices in A.C. circuit protection." Thesis, Imperial College London, 1987. http://hdl.handle.net/10044/1/7921.
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Steffensmeier, Gary. "Teachers’ pedagogical beliefs about using computing devices in one-to-one technology initiative schools." Diss., University of Iowa, 2016. https://ir.uiowa.edu/etd/2280.
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Using a qualitative multiple case study design, this study investigated the ways that teachers’ pedagogical beliefs about learning: 1) affect students’ access to and use of one-to-one technologies and 2) shape one-to-one learning environments. Results indicate that teachers’ pedagogical beliefs are not a predictor of student access to computing devices, but do impact how students use the devices in the classroom. Also, teachers’ use of technology resources reflects their pedagogical beliefs. Teachers in the study reported that the increased access to technology via a one-to-one program positively impacted the learning environment by: facilitating better communication with students; empowering students; providing better feedback to students; making the teachers’ job easier; providing teachers and students with better access to resources; allowing more ways to differentiate student learning; developing 21st century technology skills; providing variety; and helping motivate students to learn. Teachers’ perceived negative impacts of the one-to-one program centered on the difficulties of shifting to new classroom management methods that accommodate technology devices and the distractions associated with the computing devices. Teachers also reported that they need better professional development to successfully integrate technology into their classrooms. Future professional development for one-to-one programs should be directed towards developing student-centered pedagogies with a focus on collaboration and integration of technology into the educational curriculum.
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Veal, Christopher Michael John. "The damping of power system oscillators by generator control." Thesis, Imperial College London, 1989. http://hdl.handle.net/10044/1/47695.
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Arjona, Lopez Marco Antonio. "Steady state and frequency domain lumped model numerical characterisation of solid rotor synchronous generators." Thesis, Imperial College London, 1996. http://hdl.handle.net/10044/1/7548.
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Fair, Ruben Jeevanasan. "Analysis and design of electromagnetic moving coil vibration generators." Thesis, Imperial College London, 1991. http://hdl.handle.net/10044/1/7830.
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Adams, Nicholas K. "Power-factor improvement in cage induction motors." Thesis, Imperial College London, 1987. http://hdl.handle.net/10044/1/38210.
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Thong, Aaron. "Electrical characteristics of single molecule fullerene based devices." Thesis, Imperial College London, 2017. http://hdl.handle.net/10044/1/49253.
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This thesis investigates the design of a unimolecular donor-acceptor system (4TPA-C60) for the purpose of developing biomimetic Turin IETS sensors. The gas phase 4TPA-C60 molecule is calculated to have a localised double-well electronic structure, which is similar to that of a nanowire resonant tunnelling device. 4TPA-C60 decorated gold surfaces are prepared from scratch, and characterised at each step. STM imaging confirms successful grafting of the molecular species to the gold surface. Scanning tunneling spectroscopy performed on these molecular double-barrier tunnel junctions show a slightly asymmetric I(V ) profile, similar to predictions from ab initio calculations. DFT calculations also reveal that the behaviour of the device is strongly dependent on the supramolecular couplings at both metal/molecule interfaces. A new phenomenon is identified, where pinning of the LUMO to the HOMO states maintains the resonant transmission channel and prevents crossing of the frontier molecular orbitals at higher biases. The HOMO-LUMO pinning effect is determined to arise from charge accumulation on the C60 cage, due to smaller coupling at the C60/metal interface. By preventing crossing of the states, HOMO-LUMO pinning delays the onset of the NDR feature, resulting in a wider current peak and lower resolution of the sensor. Based on the charge transport mechanism, several alternative systems are proposed in which HOMO-LUMO pinning can be minimized. An endohedral fullerene derivative, 4TPA-F@C60, is found to be the most promising candidate, displaying much narrower NDR peaks. These findings not only help to improve future designs of molecular Turin IETS sensors, but also contribute significantly to our understanding in the broader field of molecular devices in general.
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Mitchison, Mark. "From thermodynamics to thermometry with single-atom devices." Thesis, Imperial College London, 2016. http://hdl.handle.net/10044/1/44566.
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This thesis presents theoretical research on microscopic measuring devices and thermal machines constructed from single trapped atoms. We study several variants on this theme, with a particular emphasis on their application to ultracold atom physics. The first part of the thesis is about quantum refrigerators powered by thermal absorption rather than by external work. We propose and detail how such a machine may be practically constructed with a trapped atom placed inside an optical cavity, and employed to cool the atom close to absolute zero temperature using only collimated sunlight as an energy source. We then show that quantum absorption refrigerators in the strong-coupling regime exhibit coherent oscillations, thus enabling one to outperform a typical classical refrigerator by reaching lower temperatures than the steady state in a finite time using quantum coherence. The second part of the thesis studies the use of impurity atoms as probes of ultracold atomic gases. We discuss two different thermometry methods using impurities which are sensitive to temperature differences on the order of nanokelvin or less. We characterise the precision of the proposed thermometers by explicit calculations in the context of both weakly and strongly interacting atomic Bose gases. Finally, we study impurities immersed in a cold atomic Fermi gas realising a superfluid. We show that the impurities' energy dissipation rate probes the spectrum of density fluctuations in the gas, providing nondestructive access to various properties of the superfluid order parameter along the crossover from a Bardeen-Cooper-Schrieffer (BCS) state to a Bose-Einstein condensate (BEC).
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Braic, Laurentiu. "Nanoscale films for near infrared active plasmonic devices." Thesis, Imperial College London, 2015. http://hdl.handle.net/10044/1/59245.
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As optoelectronic components become nano-dimensional, controlling the coupling between light and matter at the nanoscale has become a major technological challenge, as well as the subject of theoretical studies. The aim of this work is threefold. First, to assess the suitability of ferroelectric thin films - Barium Strontium Titanate (BST), and Strontium Barium Niobate (SBN), as active media for plasmonic devices. Second, to find suitable thin film electrodes for such devices, by exploring and optimizing the plasmonic behaviour of already known conductive materials, conductive oxides (Strontium Ruthenate - SRO), and transitional metal nitrides (Titanium nitride - TiN). Third, to optimize the deposition process of metallic (Silver – Ag) films, so as to improve their smoothness, and thus their suitability for plasmonic applications and lithography in general. SBN ceramic targets were sintered. SBN and BST films were deposited by PLD and ellipsometry and normal incidence reflectometry were used to examine their optical tunability. Ellipsometry was further used to measure the effects of the residual strain of the BST thin films on their optical properties. BST and SBN films were found to exhibit a birefringence under bias along the direction of growth. A residual strain variation along the films’ direction of growth was inferred from an observed non-linear change in the refractive index of BST films along that same direction. SRO and TiN films were fabricated using PLD and reactive magnetron sputtering, respectively. The effects of the deposition pressure upon structure, charge carrier concentration and mobility, and optical properties were studied using X-ray diffraction (XRD), Hall-effect measurements, and ellipsometry. The optical properties of SRO were explained based on electron concentration and structure. SRO was confirmed as a promising plasmonic material, for applications in the near infrared range and at elevated temperatures. The influence of the deposition temperature upon the optical properties of TiN films was shown. Films grown at high temperature (800oC) had quasi-metallic optical properties, while films grown at room temperature exhibited well defined plasmon bandwidth, between two distinct Epsilon-near-zero (ENZ) frequencies, which has been linked to the uniform oxidation of the samples). Finally, Ag thin films were deposited using magnetron sputtering, in an Ar/He atmosphere. The effect of the sputtering gas ratio on the films structure, morphology and reflectivity was studied using XRD, Atomic force microscopy (AFM) and visual-range normal incidence reflectometry. The addition of Helium to the sputtering atmosphere was found to reduce the roughness of Ag films and improve their reflectivity, due to the Penning effect present in the Ar-He plasma. The work undertaken has, by developing new plasmonic materials (SRO, oxidized TiN), and expanding the knowledge of the behaviour (BST) and fabrication (Ag) here has paved the way for the development of active plasmonic devices.
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Chung, Dae-Young. "Gravure printed and solution-processed polymer semiconductor devices." Thesis, Imperial College London, 2011. http://hdl.handle.net/10044/1/8962.
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The idea of printing optoelectronic devices has been developed over the last decade by various printing techniques such as screen printing, transfer printing, and inkjet printing, attributed to the advent of soluble organic semiconducting (OSC) materials. Printing of optoelectronic devices provides economical advantages for its fast and simple processing stages which is conceptually similar to the graphical printing. The advantage is expected to overcome the relatively low performance of organic materials where its charge transport is occurred by hopping process which is limited by its hopping distance and conformation of molecular chains. Printing techniques currently available should be optimized further to attract a huge impact. For example, the inkjet printing has a drawback of its low printing speed although it offers the printing of high definition pixels with its width around 60 μm. In this Thesis, gravure printing, a high throughput printing technique, is discussed to experimentally demonstrate its feasibility as a production method of optoelectronic devices. The targeted device structures are organic light-emitting diodes (OLEDs) and field-effect transistors (OFETs). Both printed OFETs and OLEDs have reached device performance similar to reference devices with the same materials and structures fabricated by spin-coating. Unlike the graphic art printing, such as is used to fabricate newspapers, magazines and posters, the printing of OSC optoelectronic devices is very sensitive to processing conditions attributed to a thickness of very thin layers, usually less than 100 nm. Therefore, the surface uniformity of the printed layers must be very planar, with a surface roughness root mean square (RMS) value typically less than 3 nm. It is found that controlling hydrodynamic forces during the thin film formation, such as the coffee stain convection flow and the surface tension driven Marangoni flow, offer a clear opportunity for achieving devices with high performance in gravure contact printed thin films. Chapter 2 and 3 discuss background theory related to experiments in this thesis. Chapter 4 is an experimental chapter explaining materials used and experimental techniques. In Chapter 5, gravure printing of OLEDs with printed poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) (PEDOT: PSS) hole injection and LUMATION Green 1300 (LG1300) light emissive layers is developed with discussions of wetting of printing formulations and fluidic movements observed during film formation. A mixture of solvent method provides the circulation of hydrodynamic flows inside the printed formulation providing a deposition of highly uniform thin film after solvent evaporation. As a result, high performance of OLEDs with its performance of 8.8 cd/A and 5.4 lm/W with a maximum brightness of 66,000 cd/m2 is reported in OLEDs where both PEDOT: PSS and LG1300 are gravure printed. The performance is the highest up to date among the OLEDs printed by the same printing method. Chapter 6 introduces an inverted structure type OLED where its high work function anode is placed on the top of the device so that it consequently improves device stability as high work function metals such as Au or Ag are less sensitive to ambient dopants. The use of carbonate or oxide layers on the top of a high work function metal at the bottom of the device induced efficient injection of electrons to the device. A very thin layer of caesium carbonate (Cs2CO3) around 5-10 nm was gravure printed onto the ITO electrode. The printed Cs2CO3 layer showed that the surface roughness is highly improved owing to molecular ordering is affected and improved by the mechanical forces such as pressure and thermal energy engaged during the printing. The inverted OLEDs with the printed Cs2CO3 layer recorded the device performance of 10 cd/A and 3 lm/W with a maximum brightness of around 7,500 cd/m2. This is a first report showing that a very thin and inorganic layer can also be gravure printed. Chapter 7 describes charge balancing and position of recombination zone in inverted OLEDs using poly (9,9-dioctylfluorene-co-benzothiadiazole) (F8BT) and poly (9,9-dioctylfluoreneco- N-(4-butylphenyl)-diphenylamine) (TFB) bilayer structure. The two layers are either hole or electron transporting materials and can form a large energy offsets between the HOMO levels and the LUMO levels of the two materials at the interface which confines a large number of injected charge carriers there. It is shown that a position of recombination zone and the charge carrier confinement effect are dependent with the thicknesses of the two polymer layers. The confined charged carriers induce the recombination zone to be positioned close to the interface where charge carrier tunnelling and Föster energy transfer occur more frequently than the bulk. The experimentally optimized thicknesses of the two layers record the highest efficiency of 36 cd/A and 23 lm/W with a bright emission of 51,200 cd/m2 at a low voltage around 4 V. The efficiency is the highest efficiency reported so far to the best of our knowledge using fluorescence materials. Chapter 8 explains gravure printing of OFETs using a thiophene polymer. Poly(3- hexylthiophene)-2,5-diyl (P3HT) OSC, two dielectric layers, and top Ag gate electrode are sequentially gravure printed. The annealing condition of P3HT, choice of dielectric layer and issues related to printing P3HT are discussed. Fully gravure printed OFETs on the pre-patterend ITO source and drain pattern report a high mobility of 3 × 10-2 cm2/Vs and an on/off current ratio of 104.62. The performance is the highest among the printed OFETs using P3HT.
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Pérez, Martín. "Conditional resource management for mobile devices." Universidade Tecnológica Federal do Paraná, 2014. http://repositorio.utfpr.edu.br/jspui/handle/1/1036.
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Dispositivos móveis, como os tablets e smartphones, ficam mais populares a cada dia. Esta nova classe de dispositivos está evoluindo constantemente em suas capacidades computacionais, permitindo os usuários trocarem computadores maiores por estes dispositivos móveis menores. Diariamente novas aplicações para estes dispositivos são desenvolvidas e publicadas em repositórios de software, possibilitando que os usuários instalem e se beneficiem de novos aplicativos rapidamente. Para gerenciar múltiplas requisições de recursos de diferentes aplicações rodando em paralelo, o design de gestão de recursos do sistema operacional desempenha um papel chave. A vasta maioria dos gerentes de recursos disponíveis nos dispositivos móveis são projetados para maximizar o desempenho do sistema como um todo, nem sempre levando em consideração as características dos processos solicitando recursos na camada de aplicação. Este tipo de estratégia pode levar a casos onde algumas aplicações experimentem tempos de latência mais longos que os desejados durante os acessos aos recursos, comprometendo a Qualidade de Serviço ou a segurança do sistema. Este trabalho tem por objetivo oferecer um novo modelo de gerência de recursos para dispositivos móveis, permitindo a criação de regras que priorizem a alocação de recursos para aplicações específicas de acordo com suas necessidades. Além disso foi implementado um prototótipo como prova de conceito deste modelo, usando a plataforma Android, para confirmando a viabilidade do mesmo.<br>Mobile devices, such as smartphones and tablets, are becoming more popular everyday. This new devices class is constantly evolving on what concerns computing capabilities, allowing users to switch from larger computers to smaller mobile devices in several cases. Everyday new apps for these devices are developed and published in software repositories, enabling users to quickly install and benefit from new software. In order to deal with the multiple resource requests from different applications running in parallel, the operating system’s resource management design plays a key role. Most resource managers available to mobile phones are designed to maximize the performance of the system as a whole, not always taking into account the characteristics of the processes requiring resources in the application layer. This type of strategy can lead to cases where some applications experience longer latencies than desired while accessing resources, compromising the Quality of Service or system security. This work aims to offer a new resource management model for mobile devices, allowing the creation of rules that can prioritize the resource allocation for specific applications according to their needs. Also it implemented a proof of concept prototype version of this model, using the Android platform, confirming its viability.
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Angladon, Vincent. "Room layout estimation on mobile devices." Phd thesis, Toulouse, INPT, 2018. http://oatao.univ-toulouse.fr/20745/1/ANGLADON_Vincent.pdf.
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Room layout generation is the problem of generating a drawing or a digital model of an existing room from a set of measurements such as laser data or images. The generation of floor plans can find application in the building industry to assess the quality and the correctness of an ongoing construction w.r.t. the initial model, or to quickly sketch the renovation of an apartment. Real estate industry can rely on automatic generation of floor plans to ease the process of checking the livable surface and to propose virtual visits to prospective customers. As for the general public, the room layout can be integrated into mixed reality games to provide a better immersiveness experience, or used in other related augmented reality applications such room redecoration. The goal of this industrial thesis (CIFRE) is to investigate and take advantage of the state-of-the art mobile devices in order to automate the process of generating room layouts. Nowadays, modern mobile devices usually come a wide range of sensors, such as inertial motion unit (IMU), RGB cameras and, more recently, depth cameras. Moreover, tactile touchscreens offer a natural and simple way to interact with the user, thus favoring the development of interactive applications, in which the user can be part of the processing loop. This work aims at exploiting the richness of such devices to address the room layout generation problem. The thesis has three major contributions. We first show how the classic problem of detecting vanishing points in an image can benefit from an a-priori given by the IMU sensor. We propose a simple and effective algorithm for detecting vanishing points relying on the gravity vector estimated by the IMU. A new public dataset containing images and the relevant IMU data is introduced to help assessing vanishing point algorithms and foster further studies in the field. As a second contribution, we explored the state of-the-art of real-time localization and map optimization algorithms for RGB-D sensors. Real-time localization is a fundamental task to enable augmented reality applications, and thus it is a critical component when designing interactive applications. We propose an evaluation of existing algorithms for the common desktop set-up in order to be employed on a mobile device. For each considered method, we assess the accuracy of the localization as well as the computational performances when ported on a mobile device. Finally, we present a proof of concept of application able to generate the room layout relying on a Project Tango tablet equipped with an RGB-D sensor. In particular, we propose an algorithm that incrementally processes and fuses the 3D data provided by the sensor in order to obtain the layout of the room. We show how our algorithm can rely on the user interactions in order to correct the generated 3D model during the acquisition process.
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Todd, Shane Truman. "Electrothermomechanical modeling of a 1-D electrothermal MEMS micromirror." [Gainesville, Fla.] : University of Florida, 2005. http://purl.fcla.edu/fcla/etd/UFE0008981.
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Finn, Jane Rebecca. "Digital image processing for mammography." Thesis, Imperial College London, 1997. http://hdl.handle.net/10044/1/8888.
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Thomas, Stuart R. "Solution processed metal oxide microelectronics : from materials to devices." Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/22162.
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Owing to their many interesting characteristics, the application of metal oxide based electronics has been growing at a considerable rate for the past ten years. High performance, optical transparency, chemical stability and suitability toward low cost deposition methods make them well suited to a number of new and interesting application areas which conventional materials such as silicon, or more recently organic materials, are unable to satisfy. The work presented in this thesis is focussed on the optimisation of high performance metal oxide based electronics combined with use of spray pyrolysis, as a low cost deposition method. The findings presented here are split into three main areas, starting with an initial discussion on the physical and electronic properties of films deposited by spray pyrolysis. The results demonstrate a number of deposition criteria that aid in the optimisation and fabrication of high performance zinc oxide (ZnO) based thin-film transistors (TFTs) with charge carrier mobilities as high a 20 cm2/Vs. Solution processed gallium oxide TFTs with charge carrier mobilities of ~0.5 cm2/Vs are also demonstrated, highlighting the flexibility of the deposition method. The second part of the work explores the use of facile chemical doping methods suitable for spray pyrolysed ZnO based TFTs. By blending different precursor materials in solution prior to deposition, it has been possible to adjust certain material characteristics, and in turn device performance. Through the addition of lithium it has been possible alter the films grain structure, leading to significantly improved charge carrier mobilities as high as ~54 cm2/Vs. Additionally the inclusion of beryllium during film deposition has been demonstrated to control TFT threshold voltages, leading to improved integrated circuit performance. The final segment of work demonstrates the flexibility of spray pyrolysis through the deposition of a number of high-k dielectric materials. These high performance dielectrics are integrated into the fabrication of TFTs already benefiting from the findings of the previously discussed work, leading to highly optimised low-voltage TFTs. The performance of these devices represent some of best currently available from solution processed ZnO TFTs with charge carrier mobilities as high as 85 cm2/Vs operating at 3.5 V.
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Rosenblatt-Weinberg, Florence. "Modelling and optimisation of Electro-Active Polymer (EAP) devices." Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/17855.
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The control of boundary layers either for skin-friction reduction or for fight control can be achieved by their manipulation using deformable surfaces. In the case of the former, it is known that the manipulation of coherent structures in the turbulent boundary layer can lead to significant drag reductions. However, the challenge is to find actuators and sensors that are functional at these spatial scales (10 micron to 0.1 mm) and the associated temporal scale (100 kHz). Electro-Active Polymers (EAPs) provide excellent performance, are light weight, flexible, and low cost. Therefore EAPs, and in particular Dielectric Elastomer Actuators (DEAs), provide many potential applications as micro-actuators and micro-sensors. Modelling DEA devices is a cost-effective way of providing a better understanding of the devices and optimising their designs. Acquiring a model for the EAP material itself is the first essential step in DEA modelling. A modelling technique taking into account the material non-linearities and its behaviour at large deformations (`hyperelasticity') is presented in the third chapter of this thesis. The main challenge in modelling DEA devices is the modelling of their electro-mechanical coupling. Commercially available electro-mechanical modelling does not apply to non-linear materials such as EAPs. The ANSYS Finite Element (FE) software is the tool used in this work to develop a novel model presented in the fourth chapter. Various means of optimising the design of DEA devices are suggested in the sixth chapter using the developed DEA model. A novel design of an EAP-based pressure sensor is suggested in the seventh chapter; FE modelling is used to study the abilities and performance of such a device. To complete the model, its time-dependent properties are examined by a modal analysis examined in an eighth chapter. The thesis is completed by examining the potential for DEA in providing a `smart' surface for distributed aerodynamic control.
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Wade, Jessica Alice Feinmann. "Nanometrology for controlling and probing organic semiconductors and devices." Thesis, Imperial College London, 2016. http://hdl.handle.net/10044/1/56219.
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Organic semiconductors continue to attract interest due to their potential applications in printable, low-cost, high throughput, flexible electronic devices, which could profoundly impact the large area electronics and semiconductor industries. The performance and stability of such devices is strongly influenced by the chemical composition and molecular packing of the organic semiconducting material. This thesis considers a range of solution processing techniques, which can be used to control the molecular packing of polymeric and small molecular organic semiconductors, and employs a range of complementary spectroscopic and electronic characterisation techniques to elucidate the complex relationships between thin film morphology and optoelectronic device performance. By understanding these effects, we are able to control the deposition processes in order to yield optimised morphologies for high-performance organic field effect transistors, magnetic tunnel junctions, and photovoltaic devices. We first develop a highly controlled solution deposition system that offers precise control of the thermal conditions and rate of solution deposition. The zone-casting technique is optimised to print uniaxially aligned needle-like domains of small molecule organic semiconductors. We establish a robust structural probe, Raman spectroscopy, to interpret the well-defined packing motifs. The characterisation of molecular packing is extended to vacuum deposited organic thin films. For both pentacene and phthalocyanine materials, we identify strong interactions between the organic layer and the substrate, which can be modified using self-assembled monolayers, inorganic interlayers and temperature control. We are able to produce films with uniform molecular packing and an optimised molecular orientation such that the charge carrier mobility or magnetoresistance of transistor or tunnel junction devices are increased by several orders of magnitude. Finally we consider organic photovoltaic devices, where modifications to the chemical structures of conjugated polymers provide an effective means of controlling both molecular packing and device stability. We investigate the impacts of a number of structural modifications on the molecular packing and stability of the benchmark material poly(3-hexyl)thiophene. We consider the operational stability of these materials and find that increased planarity of the conjugated backbone and a deeper ionisation potential do not necessarily result in long device lifetimes. For polymer/fullerene blend films, we identify how the size and loading of the acceptor molecules influences the polymer molecular packing. Both the specific conclusions drawn in this thesis and the techniques for morphological control and characterisation are highly relevant to a broad range of organic semiconducting materials and device architectures. Our findings have particular relevance to the issues of optimised solution deposition and device stability, which are of critical importance to the emerging industry of printed electronics.
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Bronstein, Hugo. "Electrophosphorescent materials for use in organic light emitting devices." Thesis, Imperial College London, 2009. http://hdl.handle.net/10044/1/11225.
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Rueda, Juan Enrique Martinez. "Energy dissipation devices for seismic upgrading of RC structures." Thesis, Imperial College London, 1997. http://hdl.handle.net/10044/1/8019.
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Bishop, James William. "Hot-spot heating and non-uniformities in photovoltaic devices." Thesis, Imperial College London, 1988. http://hdl.handle.net/10044/1/46965.
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Siabi-Shahrivar, Nasser. "A study of 1/f noise in polysilicon emitter transistors." Thesis, University of Southampton, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.314728.
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Patni, Chandra Kumar. "Digital control of permanent magnet motors." Thesis, Imperial College London, 1989. http://hdl.handle.net/10044/1/47613.
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