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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
461

Fostering the responsible citizen : citizenship and sexuality in the Girl Guides of Canada, 1979-1999

Faingold, Elizabeth 11 1900 (has links)
The Girl Guides of Canada is a youth service organization, serving almost 10% of the Canadian female population aged 5-17, that aims to teach girls and young women to become responsible citizens. In this thesis, I review the curriculum of the Pathfinder branch (for girls and young women aged 12-15) of the Girl Guides of Canada. Using feminist, anti-racist, and queer perspectives, I treat "responsible citizenship" as a discursive concept and conduct a discourse analysis of the Pathfinder programme to discover how it attempts to gain the consent of girls and young women to particular definitions of responsible citizenship. Drawing on feminist citizenship theory developed by Yuval-Davis, Anthias, Alexander, and Ross, I argue that the state implicates select female citizens in nation building practices as biological reproducers and transmitters of culture. I also draw on theories of moral regulation extended by Sangster, Strange, and Loo to illustrate ways in which the state and voluntary organizations attempt to gain the consent of citizens to particular ways of being. I argue that, because its texts authorize particular definitions of responsible citizenship, the Pathfinder curriculum implicates girls and young women in capitalist nation building in Canada. Specifically, I argue that the Pathfinder programme normalizes heterosexuality, whiteness, and ability, and privileges middle-class values. I also demonstrate that a responsible citizen, according to the Pathfinder curriculum, performs caregiving and environmental stewardship as volunteer service, prepares to join the labour force, and is healthy, hygienic, cheerful and obedient. I raise questions about the nature of the organization's efforts to teach about sexism, racism, classism, ableism, homophobia and heterosexism, and suggest some ways in which the curriculum can attend to these social relations to develop a more inclusive image of the ideal responsible citizen. I also suggest a number of directions for future research. / Arts, Faculty of / Anthropology, Department of / Graduate
462

Moléculas fotônicas para aplicações em engenharia espectral e processamento de sinais ópticos / Photonic molecules for applications in spectral engineering and optical signal processing

Barêa, Luís Alberto Mijam, 1982- 06 May 2014 (has links)
Orientador: Newton Cesário Frateschi / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Física Gleb Wataghin / Made available in DSpace on 2018-08-24T10:26:52Z (GMT). No. of bitstreams: 1 Barea_LuisAlbertoMijam_D.pdf: 8459370 bytes, checksum: 5dd565986711cb06cb24cf63d6d69372 (MD5) Previous issue date: 2014 / Resumo: Sistemas fotônicos baseados em ressonadores na forma de anéis tem uma dependência fundamental dada pela relação estreita entre espaçamento espectral livre (Free Spectral Range, FSR), fator de qualidade total, Q, e o raio dos ressonadores, R. Nesta tese, nós quebramos esta dependência empregando moléculas fotônicas (Photonic Molecules, PMs) baseadas em múltiplos anéis internamente acoplados a um anel externo, que por sua vez está acoplado a um guia de onda. Aplicando o método de matriz de transferência (Transfer-Matrix Method, TMM) e programas robustos de simulação, nós projetamos três tipos de PMs baseada em uma plataforma de Silício-sobre-isolante (Silicon-on-Insulator, SOI). Este projeto mostrou que o acoplamento entre duas ou mais micro-cavidades ópticas, permite separações espectrais e hibridização dos modos quando as frequências ressonantes estão degeneradas nas cavidades, similar ao acoplamento fraco entre átomos. Estas PMs foram fabricadas com um processo convencional e compatível com a tecnologia CMOS, empregando uma Foundry, e suas caracterizações mostraram a emergência de dupletos, tripletos, quadrupletos e sextupletos de ressonâncias degeneradas, com alto Q e espaçamentos curtos, somente possíveis com anéis de algumas ordens de magnitude maiores em área. Estes resultados quebraram o paradigma da interdependência entre Q, FSR e R, evidenciando que é possível ter tempo de vida fotônico, espaçamento espectral e área independentes. As aplicações destas PMs em processamento de sinal óptico também foram demonstrados neste trabalho. Nós apresentamos o uso da molécula com dupleto de ressonâncias para extrair um sinal RF de 34.2 GHz, filtrando as bandas laterais de um sinal modulado. Também foi demonstrado que moduladores ópticos ultracompactos operando à 2.75 vezes acima do limite da largura de linha do ressonador pode ser obtido a partir da PM que apresenta um tripleto de ressonâncias, separadas de ~55 GHz. Finalmente, utilizando a molécula que permite obter um quadrupleto de ressonâncias, foi demonstrado a conversão de comprimento de onda totalmente óptico (multicasting) para quatro canais convertidos e separados de 40-60 GHz, utilizando apenas 1 mW de potência de controle / Abstract: Photonic systems based on microring resonators have a fundamental constraint given by the strict relationship among free spectral range (FSR), total quality factor (Q) and resonator size (R). In this thesis, we break this dependence employing CMOS compatible photonic molecules (PMs) based on multiple inner ring resonators coupled to an outer ring, which is coupled to a straight bus waveguide. Applying the transfer matrix method (TMM) and simulation robust programs, we project three types of PM based on scalable silicon-on-insulator (SOI) platform. This project shows that the coupling between two or more optical micro-cavities, allows spectral splitting and hybridization of the modes when the resonant frequencies are degenerated in the cavities, similar to weak coupling between atoms. These PMs were fabricated in a conventional CMOS Foundry and your characterization shows the emergence of doublet, triplet, quadruplet and sextuplet of degenerated resonances, with high-Q and close-spaced, only achievable with single-ring orders of magnitude larger in footprint. These results break the paradigm of the interdependence between Q, FSR and R, evidencing that is possible to have photonic lifetime, spectral spacing and footprint independents. The applications of these PMs in optical processing signal were also demonstrate in this work. We demonstrate the use of the doublet splitting for 34.2 GHz RF signal extraction by filtering the sidebands of a modulated optical signal. We also demonstrate that very compact optical modulators operating 2.75 times beyond its resonator linewidth limit may be obtained using the PM triplet splitting, with separation of ~ 55 GHz. Finally, using the quadruplet of resonances, we demonstrate four-channel all-optical wavelength multicasting using only 1 mW of control power, with converted channel spacing of 40-60 GHz / Doutorado / Física / Doutor em Ciências
463

[pt] MATRIZ DE ESPELHAMENTO DE OBSTÁCULOS CILÍNDRICOS DE ALTURA VARIÁVEL EM GUIAS DE ONDAS RETANGULARES / [en] SCATTERING MATRIZ OF CYLINDRICAL POSTS WITH VARIABLE HEIGHT IN RECTANGULAR WAVEGUIDES

16 August 2006 (has links)
[pt] Neste trabalho obtém-se a matriz de espalhamento de obstáculos cilíndricos em guias de ondas retangulares. O método de análise utilizado é o método dos momentos juntamente com o método das imagens. São analisadas descontinuidades formadas por um poste vertical inteiro, postes verticais contendo um gap central, postes horizontais contendo um gap central e postes localizados nas quatro paredes do guia de ondas retangular. Os resultados obtidos são comparados com valores experimentais para as 4 geometrias descritas acima. Além disso é feita a comparação dos resultados obtidos com os do método variacional para o caso do poste vertical inteiro. / [en] In this work the scattering matrix of cylindrical obstacles in rectangular wavwguides is obtained. The analysis method adopted is the moment method in junction with the image method. Discontinuities formed by a single vertivcal post, vetical posts with a central gap, horizontal posts with a central gap, and posts on the four waveguides walls are analyzed. The results are compared with experimental data for the four geometries described above. Moreover the results are also compared with those obtained by variational method in the case of the single vertical post.
464

Hodnocení tubusového světlovodu / Light Guide Evaluation

Omishore, Ayodeji January 2020 (has links)
Light guide is a tubular skylight with mirrored internal surface. It is a lighting device bringing daylight into the interior of a building without windows or into rooms with insufficient daylight. It presents the potential for energy savings, opens the possibility to use places that are not well lit and offers opportunities for improving the visual comfort of the indoor environment. This thesis reviews the potential of light guide system as a daylighting approach in building and presents results of experiments on performance of tubular skylight prototype. The main task of the thesis is focused on comparison of traditional light guide system and newly developed prototype, examination of its light transmittance and efficiency as well as its thermal behaviour in order to find possible improvements for applications in buildings.
465

Micro-résonateurs intégrés pour des applications capteurs / Integrated microresonator for sensing application

Girault, Pauline 14 December 2016 (has links)
Les micro-résonateurs (MRs) sont devenus des éléments clés de la conception de capteurs optiques intégrés, car étant plus miniaturisés que l’existant, ils s’intègrent mieux dans des systèmes ''lab-on-chip'', ce qui permet aussi de réduire le volume des molécules à détecter. Les MRs sont de plus très sensibles à la variation d’indice effectif provoquée par la présence de molécules dans le milieu de détection. Dans cette thèse, nous avons utilisé deux types de matériaux différents: les polymères et le silicium poreux. Les polymères, facilement réalisables avec des méthodes de fabrication peu onéreuses, sont dans un premier temps utilisés pour valider les outils de simulation développés pour l’étude des caractéristiques des MRs pour l’application capteur basée sur la détection par évanescence. Le silicium poreux permet d'exploiter un autre mode de détection, la détection en volume. Les molécules présentes dans le milieu de détection s'infiltrent dans le matériau et réagissent de manière directe avec la lumière. En utilisant les outils de simulation développés et en adaptant le procédé de photolithographie classique utilisé pour la fabrication de MRs en polymères, des premiers MRs constitués de guides ridges à base de silicium poreux sont mis en œuvre et caractérisés. Ces travaux de thèse démontrent expérimentalement la possibilité de détecter des concentrations de glucose avec une meilleure sensibilité que l'état de l'art pouvant atteindre les 600 nm/RIU, pour les domaines utilisant la détection et l'analyse de molécules (santé-agro, défense-sécurité, environnement). / Micro-resonators have become key element for integrated optical sensor because they offer the advantage of significantly minimizing the device size, which allows an easily integration on lab-on-chip and greatly reduces the amount of molecules to be detected. Moreover, micro-resonators are extremely sensitive to the effective index variation induced by the presence of molecules in the detection medium. The thesis focuses on two different materials: polymers and porous silicon. Firstly, polymers, easily implementable with a low cost fabrication, are used to validate the simulation tools developed for the study of micro-resonators characteristics in order to perform sensing application based on the detection by evanescence. Then, porous silicon is investigated in order to operate another type of detection, the detection by volume. The molecules to be detected and present in the medium detection infiltrate into the material and interact directly with the light. Using simulation tools and by adapting the photolithographic process used for polymers micro-resonators fabrication, the first micro-resonators based on porous silicon ridge waveguides are obtained and characterized. The work contained in this thesis demonstrate experimentally the possibility of sensing concentrations of glucose with a sensitivity of 600 nm/RIU, using volume detection, which is higher than the state of the art, for domains using the sensing and analysis of molecules (health, food industries, security and environment).
466

A Study of 21st-Century Works for Clarinet and Multimedia Featuring Three Newly Commissioned Works for Clarinet and Electronics with Visuals

January 2020 (has links)
abstract: In the fast-paced, technology-driven society of today, new demands are placed on artists to re-think how music is presented and communicated to the world. Access to the internet, development of sound manipulation software, and broader means of use and distribution through the digital music industry have drastically shifted the way the twenty-first century artist creates and performs music. One of the most striking changes that occurred is the increased use of visual material as a vehicle to enhance and contribute to the depth and intrigue of live performances and recordings. This project researches twenty-first century works for clarinet and multimedia that specifically include a visual element (including but not limited to images, fixed and interactive video, light effects, and choreography) and highlights the prevalence of this genre in contemporary repertoire. Discussion begins with a brief overview of the history of multimedia, its relation to the clarinet, and how it has been defined by the twenty-first century. Additionally, in order to contribute to this ever-growing repertoire, three new works for clarinet and multimedia were commissioned in collaboration with composers and visual artists. These new works include: Roadrunner (2019) for clarinet and fixed electronics by Spencer Brand with video by Samuel Proctor; I’d known this place (2020) for clarinet and electronics by Dan Caputo with live audio generative animations by Andrew Robinson; and Spectral Passages (2020) for clarinet and electronics by Alvaro Varas with painting by Miguel Godoy. Background information and performance guides are included for each piece to aid future musicians in performance, as well as respective audio/video recordings. Finally, a significant portion of this document includes a catalog of works for clarinet and multimedia. The catalog was compiled by focusing on the output of twenty-first century composers to serve as a resource for future performers. / Dissertation/Thesis / Roadrunner for clarinet and electronics by Spencer Brand / Spectral Passages for clarinet and electronics by Alvaro Varas / I'd known this place for clarinet and electronics by Dan Caputo / Doctoral Dissertation Music 2020
467

A Countertenor Aria Collection Continuum for Studio Training and Performance

Stanley, David Thomas 08 1900 (has links)
An assessment of the standard voice instructor or performer collection of printed music would likely reveal numerous operatic repertoire volumes in anthology format appropriated to the primary four voice categories. However, thorough investigation divulges little in comparable printed material accessible to the countertenor. This scarcity of systemized collections is especially evident in the territory of comprehensive countertenor operatic repertoire. This project fills that present void by creating a compilation of sixteen countertenor arias drawn from various styles and historical periods for suggested application in studio instruction and performance. Perhaps, a more meaningful project intent is the presentation of a beneficial graded literature continuum resource for the studio teacher who instructs a countertenor in various stages of vocal development. For this purpose, each of the 16 arias is categorized into four difficulty levels based on considerations of range, tessitura, coloratura demands, rhythm, sustained phrase length, tonality, melodic considerations/overall musical difficulty, accompaniment support, and ornamentation requirements. The project also addresses common issues of pedagogy and ornamentation for voice teacher consideration when instructing a developing countertenor.
468

LibGuides: Customizing Subject Guides for Individual Courses

Adebonojo, Leslie G. 29 November 2010 (has links)
Reference librarians at East Tennessee State University's Sherrod Library identified LibGuides as an efficient way to introduce undergraduate students, particularly those in their first two years of college, to the university library. Selecting pertinent library resources based on a course syllabus and creating a LibGuide for the course provides the students with a limited number of relevant materials. Librarians and professors view the use of subject guides attached to a course management system site as an effective educational solution. Librarians facing exponentially expanding resources and first-year students who are used to turning to Google for all their information needs can utilize LibGuides to guide students toward more relevant library resources.
469

Guidentity : A guided journey through identification; exploring the case of international tour guides

van den Born, Remco Willem January 2021 (has links)
Tour guides are often required to be a certain version of themselves while selling a particular state of mind to their guests. The job and its lifestyle suggest many influences on tour guides’ identities. Guiding involves working in an emotional environment, representing different groups simultaneously, wearing different ‘masks’ throughout a given working day, and living a unique lifestyle. By interviewing international guides leading active, multi-day, luxury trips, this study explores a broad range of factors that might influence their identity. It analyzed how their work context relates to their idea and sense of self, mainly as a tour guide but also what that means to their perceived place in the world as a person. The study found that the guides highly value the human connections in their job, and they have a strong sense of belonging to their co-leader community. They identify as separate from society by living a peculiar, dynamic, and challenging lifestyle, avoiding settling down. Moreover, they see themselves as socially competent, and they derive purpose and meaning from the job by assuming different roles that make a positive difference for the guests they encounter. The life satisfaction, self-esteem, and confidence that emerges is so gratifying that to a certain extent they forgive the unsustainable practices of their employer. However, the exposure to negative environmental impacts brings about many negative emotions, and even though they try, the minimal impact they individually have on reducing these impacts bothers them and negatively influences their well-being.
470

Subwavelength engineering of silicon waveguides and cavities for nonlinear photonics / Ingénierie des sous-longueurs d'onde de guides d'ondes et de cavités en silicium pour la photonique non linéaire

Zhang, Jianhao 19 October 2019 (has links)
Les effets Pockels de deuxième ordre et les effets Kerr de troisième ordre font partie des effets importants exploités pour la modulation de la lumière et la génération de sources dans les plateformes technologiques de la photonique intégrée. Pour tirer parti de ces non-linéarités en photonique au silicium, l'utilisation de structures optiques sub-longueurs d'onde a été explorée. Dans ce contexte, ce travail de thèse s'est concentré sur deux aspects principaux, notamment : 1) L’exploration d'un nouveau schéma de cavité photonique pour tirer profit de l'effet Pockels électro-optique dans les structures de silicium contraint pour la réalisation de modulateurs ultra-rapides à faible consommation ; 2) L’exploration d'une nouvelle famille de guides d'ondes conduisant à une satisfaction automatique des lois de conservation énergie/vecteur d’onde pour la génération de peignes de fréquence Kerr au sein des plateformes photoniques intégrées (notamment silicium).Pour améliorer les performances des modulateurs optiques Si résonants intégrés, nous avons mis au point un nouveau résonateur à cavité de Fano qui, grâce à une ingénierie sub-longueur d'onde (λ=1.55µm), a permis d'obtenir simultanément un taux d'extinction élevé (23 dB) avec un faible facteur Q de seulement 5600, et caractérisé par une très faible consommation électrique inférieure à 5 fj/bit quand on utilise l'effet de modulation par dispersion plasma des porteurs libres. Nous avons étendu la méthode à la conception d'une structure de modulation Fano en silicium contraint dont les performances souffrent traditionnellement de la faible amplitude de l'effet Pockels induit par la déformation exploitée et des pertes micro-ondes considérables dues à des composants de grande surface. Au moyen du résonateur Fano ultra-compact à structuration sub-longueur d'onde, une amélioration d'environ 200 fois/60 fois (facteurs Q de 32000/5600) du rapport d'extinction de modulation avec la même tension de commande a été théoriquement prévue. Pour améliorer l'exploitation des non-linéarités Kerr des structures silicium, nous avons proposé une nouvelle famille de guides d'ondes optiques pour satisfaire automatiquement les lois de conservation de l'énergie et du vecteur d’onde des procédés de mélange à quatre ondes (FWM). La conception de la section des guides d'ondes est basée sur un principe hérité des puits quantiques et des concepts hérités des structures sub-longueur d'onde pour la réalisation des profils d'indice particuliers. En nous basant sur ces guides d'ondes spécifiques en terme de dispersion chromatique, nous les avons appliqués à la modélisation des micro peignes de fréquence (en utilisant des résonateurs à micro anneaux) en résolvant l’équation non linéaire pertinente (Lugiato-Lefever) pour analyser de façon dynamique le processus de génération du spectre des peignes à solitons dans diverses configurations. En complément de ce modèle, les guides d'ondes sub-longueur d'onde à accord de phase automatique ont été considérés pour étendre la largeur de bande des peignes de fréquence à solitons, démontrant une largeur de bande élargie et une meilleure flexibilité dans la réalisation des peignes de fréquence relativement aux démonstrations des travaux précédents. Dans l'ensemble, l'une des caractéristiques dominantes de notre étude a été de contribuer à montrer que les structures photoniques sub-longueur d'onde pouvaient apporter des solutions concrètes aux problèmes utiles à la réalisation de fonctions non linéaires sur puce. Les nano-structures sub-longueur d’onde permettent non seulement une amélioration des circuits photoniques passifs, sujet intensivement développé depuis dix ans, mais ont également un fort potentiel pour la réalisation des fonctions actives. Cette boîte à outils de structures sub-longueur d'onde est décisive dans la pratique pour la réalisation concrète de fonctions optiques nonlinéaires intégrées, en particulier en photonique silicium. / Second-order Pockels and the third-order Kerr effects are among the important effects exploited for light modulation and light generation in integrated photonic platforms. To take advantage of these nonlinearities in silicon photonics, especially due to the lack of second order effect in bulk Si, the use of subwavelength optical structures is explored. In this context, this thesis work has focused on two main aspects, including: 1) Exploration of a novel photonic cavity scheme to take benefit of the electro-optical Pockels effect in strained Si structures for the realization of ultra-fast lower-consumption compact silicon modulators; 2) Exploration of a new family of waveguides leading to an automatic satisfaction of energy/momentum conservation for the purpose of Kerr frequency comb generation in integrated photonic platforms. For improving the performances of integrated silicon resonant optical modulators, we have developed a novel Fano cavity resonator enabled by sub-wavelength engineering, leading simultaneously to high extinction ratio (23 dB) with a small Q factor of only 5600, and characterized by an ultra-low power consumption of less than 5 fj/bit when relying on the free carrier plasma dispersion effect. We have further extended the method to design a strained silicon Fano modulation structure which performances traditionally suffer from the weak amplitude of the exploited strain-induced Pockels effect and from considerable microwave losses due to large footprint components. By means of the proposed ultra-compact subwavelength structured Fano resonator, around 200-fold/60-fold (Q factor of 32000/5600) improvement on the modulation extinction ratio with the same driven voltage was theoretically predicted. For improving the exploitation of silicon Kerr nonlinearities, we have proposed a novel family of graded index optical waveguides intending to automatically fulfill the energy and momentum conservation laws of four-wave mixing processes. The design of the waveguide section is based on a principle inherited from quantum wells of wave mechanics and concepts inherited from subwavelength structures for the practical realization of the rather particular index profiles. Standing on these specific waveguides in term of light dispersion, we have applied them to the modeling of frequency micro-combs (e.g. frequency combs generated using micro-ring resonators and a CW light source) by solving the nonlinear relevant equations (Lugiato-Lefever) to dynamically analyze the soliton comb spectrum generation process in various configurations. On top of this model, the specifically automatically phase-matched sub-wavelength-enabled graded-index waveguides were considered to trim and extend the bandwidth of silicon soliton frequency combs, demonstrating enlarged bandwidth and improved spectrum design flexibility with respect to previous works. Overall, one of the dominant features of our study was to contribute to showing that sub-long wavelength photonic structures could provide concrete solutions to problems useful for the realization of on-chip non-linear functions. Subwavelength/nano structures not only benefit to passive photonic circuits which have been intensively developed in the past ten years, but also show strong potentials in the realization of active functions. This subwavelength toolbox is decisive in practice for the concrete achievement of the objectives pursued.

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