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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.
91

From opera theatre to home theatre: (the making of) theatrical spaces and devices in the landscape

Rafferty, S.B., Art, College of Fine Arts, UNSW January 2008 (has links)
From opera theatre to home theatre (the making of) theatrical spaces and devices in the landscape -- No abstract provided.
92

First in! expeditionary airbase seizure and operations power projection through mobility warriors /

DeMarco, J. William. January 2004 (has links) (PDF)
Thesis (M.A.A.S.) -- Air University, 2004. / Title from PDF title page (viewed on April 24, 2009). "June 2004." Includes abstract. Includes bibliographical references (leaves 130-136).
93

Étude de la fabrication de cathodes par déposition par plasma H.F de poudres d'Al-Ni et Al-Ni-Mo

Lemoine, Glen. January 2001 (has links)
Thèses (M.Sc.A.)--Université de Sherbrooke (Canada), 2001. / Titre de l'écran-titre (visionné le 20 juin 2006). Publié aussi en version papier.
94

Measurement of gas bubbles in a vertical water column using optical tomography

Ibrahim, Sallehuddin January 2000 (has links)
This thesis presents an investigation into the application of optical fibre sensors to a tomographic imaging system for use with gas/water mixtures. Several sensing techniques for measurement of two component flow using non-intrusive techniques are discussed and their relevance to tomographic applications considered. Optical systems are shown to be worthy of investigation. The interaction between a collimated beam of light and a spherical bubble is described. Modelling of different arrangements of projections of optical sensing arrays is carried out to predict the expected sensor output voltage profiles due to different flow regimes represented by four models. The four flow models investigated are: a single pixel flow, two pixels flow, half flow and full flow models. The response of the sensors is based on three models: optical path length, optical attenuation and a combination of optical attenuation model and signal conditioning. In the optical path length model, opaque solids or small bubbles, which are conveyed, may totally or partially interrupt the optical beams within the sensing volume. In the optical attenuation model, the Lambert-Beer's Law is applied to model optical attenuation due to the different optical densities of the fluids being conveyed. The combination of optical attenuation model and signal conditioning is designed to improve the visual contrast of the tomograms compared with those based on the optical attenuation model. Layergram back-projection (LYGBP) is used to reconstruct the image. A hybrid reconstruction algorithm combining knowledge of sensors reading zero flow with LYGBP is tested and shown to improve the image reconstruction. The combination of a two orthogonal and two rectilinear projections system based on optical fibres is used to obtain the concentration profiles and velocity of gas bubbles in a vertical column. The optical fibre lens is modelled to determine the relationships between fibre parameters and collimation of light into the receiver circuit. Modelling of the flow pipe is also carried out to investigate which method of mounting the fibres minimises refraction of the collimated light entering the pipe and the measurement cross-section. The preparation of the ends of the optical fibre and design of the electronics, which process the tomographic data, are described. Concentration profiles obtained from experiments on small bubbles and large bubbles flowing in a hydraulic conveyor are presented. Concentration profiles are generated using the hybrid reconstruction algorithm. The optical tomographic system is shown to be sensitive to small bubbles in water of diameter 1-10 mm and volumetric flow rates up to 1 1/min, and large bubbles in water of diameter 15-20 mm and volumetric flow rates up to 3 1/min. Velocity measurements are obtained directly from cross correlation of upstream and downstream sensors' signals as well as from upstream and downstream pixel concentration values. Suggestions for further work on optical tomographic measurements are made.
95

Analysis of the cold gas spraying process and determination of selected properties of metallic coatings on polymers / L'analyse du processus de la projection à froid et la détermination de certaines propriétés des revêtements projetés de poudres métalliques sur les substrats en polymères / Analiza procesu natryskiwania zimnym gazem oraz określenie wybranych właściwości powłok metalowych na polimerach

Malachowska, Aleksandra 22 March 2016 (has links)
Le but de cette thèse de doctorat état d’analyser la possibilité de la métallisation des couches des polymères à l’aide de la méthode de pulvérisation avec du gaz froid sous une basse pression. Deux substrats thermoplastiques et cinq poudres métalliques ont été étudiés. Les substrats étaient le polycarbonate amorphe et le polyamide 6 semicristalin. La poudre était : sphérique, globulaire, dendrique cuivre, aluminium et étain. Le processus de déposition s'est avéré beaucoup plus complexe que dans le cas du substrat de métal. Les problèmes étaient, entre autres : faible dureté du substrat, comportement fragile dans les basses températures, l'amollissement thermique dans des températures très basses. Le travail a commencé avec un calcul de la vitesse dans une basse pression du processus de pulvérisation a froid. La vitesse calculée pour toutes les poudres sauf l'étain étaient au-dessous de la vitesse critique pour les paramètres acceptables en ce qui concerne la déposition des polymères. Les premières épreuves ont confirmé que la déformation des particules de poudre n'était pas suffisante. Dans le cas de cuivre, il était impossible d'obtenir le revêtement. En plus, la force de liaison était très faible - les revêtements étaient delaminés spontanément. Deux mesures ont été entreprises pour améliorer les résultats : réduire la vitesse critique de la poudre et insérer des couches intermédiaires. Avec ces deux moyens, il a été possible d'obtenir les revêtements en cuivre et alluminium sur PA6 et PC. En s'appuyant sur l'étude, des conditions optimales pour la déposition de revêtement ont été choisies pour la caractérisation. La caractérisation des revêtements a inclu : l'analyse structurelle avec le microscope à la lumière et électronique à balayage, mesure d'adhésion, mesures du module d'Young, résistivité électrique, mesures de micro-dureté, mesures de coefficient de dilatation thermique, mesures de contenu d'oxygène et la simulation FEM pour étudier le mécanisme de déposition. / The aim of this Phd thesis was to analyze the possibility of metallization of polymers surface using a Low-Pressure Cold Gas spraying method. Two polymers substrate: polyamide 6 (Pa 6) and polycarbonate (PC) were investigated. The coatings were deposited using: tin, aluminium and copper powders. Within the framework of this work powders particles velocity and temperature was calculated during spraying process. The obtained particle velocity was compared to the critical velocity to select initial spraying conditions. Direct spraying on polymers substrate brought acceptable properties only for tin powder. Aluminium coatings delaminated spontaneously after spraying process. In case of copper powder deposition of continuous layer was impossible. Next, the influence of powder morphology, heat treatment of the feedstock material and the use of interlayers on the deposition process was investigated. Consequently, aluminium and copper coatings were obtained on both polymers. For a set of received coatings (Sn, Al, Cu) microstructure was observed and the results of adhesion, resistivity, micro-hardness, Young's modulus, and oxygen content in powders and coatings measurements were given. The bonding mechanism of the powder particles with substrate material was investigated using simulation of impact of copper and tin particle on polyamide substrate in Abaqus program. The simulation results were compared to experimental results. The dissertation was summed up with conclusion and possibilities of further research. / Celem niniejszej rozprawy doktorskiej była analiza możliwości metalizacji powierzchni tworzyw sztucznych za pomocą metody niskociśnieniowego natryskiwania zimnym gazem (z ang. Low-Pressure Cold Spraying – LPCS). Jako podłoże zastosowano dwa polimery: poliamid 6 (PA 6) i poliwęglan (PC). Powłoki zostały wykonane z użyciem proszków: cyny, aluminium i miedzi. W ramach pracy obliczono prędkość oraz temperatura cząstek proszku podczas procesu natryskiwania. Na podstawie porównania otrzymanych wyników prędkości cząstek proszku do prędkości krytycznej dobrano wstępne parametry procesu. W przypadku bezpośredniego natryskiwania na tworzywo jedynie powłoki cynowe charakteryzowały się akceptowalnym właściwościami. Powłoki aluminiowe miały tendencje do samoistnego odspajania. W przypadku prób nanoszenia proszku miedzi nie udało się uzyskać ciągłej warstwy. W dalszej kolejności zbadano wpływ morfologii i obróbki cieplnej proszku oraz zastosowania międzywarstw na proces formowania powłoki, co pozwoliło na uzyskanie powłok aluminiowych i miedzianych na powierzchni obydwu tworzyw sztucznych.Dla kompletu uzyskanych powłok (Sn, Al, Cu) przedstawiono zdjęcia mikrostruktury oraz wyniki pomiarów wyniki pomiarów przyczepności, rezystywności, mikrotwardości,modułu Younga, zawartości tlenu w proszku i powłoce. Mechanizm wiązania cząstek proszku z materiałem podłoża przeanalizowano za pomocą symulacji uderzenia cząstek miedzi i cyny w podłoże poliamidowe w programie Abaqus. Wyniki z symulacji zostały porównane do rezultatów eksperymentalnych. Całość pracy podsumowano wnioskami oraz przedstawiono możliwości dalszych badań.
96

Fringe Projection Technique for Deformation Measurements under Impact Loading

Rai, Mani Ratnam January 2017 (has links) (PDF)
High-resolution three-dimensional (3D) shape reconstruction of objects has huge potential for applications in the field of design, security, entertainment, biomedicine, industrial quality control etc. Of the available techniques, optical methods have the distinctive advantage of facilitating non-contact and non-intrusive measurements. Of late, integration of optical measurement system with the computer based data processing has improved the quality of the results. Of the available techniques, structured-light illumination (Fringe Projection) is the most effective, owing its simplistic experimental architecture and analysis. Traditional Fringe Projection techniques function with the use of fringes generated using interferometric methods. With the advent of digital light projectors, digitally generated fringes have taken the place of interferometry based fringes. Despite the technological advances that this field has witnessed over last couple of decades, digital fringe projection technique still suffers from various shortcomings. This thesis presents a strategic solution to the challenges faced by the technique in its application to out-of-plane deformation measurement of objects under impact loading. First part of the thesis reports the developmental work on building an LED-Grating based optical projection system for implementation of linear-fringe projection profilometry. Successful use of the developed system in measuring out-of-plane deformation experienced by multiple targets under impact loading with a time sapling of 20,000 frames per second is re-ported. However, for performing ballistic impact measurements using the liner-fringe projection method, an order of magnitude higher time-sampling is needed. This is due to the disadvantages associated with linear fringe projection technique: (1) results in wrapped phase map (2p ambiguity) estimation, and (2) the deformation/shift of the recorded fringe pattern in the modulation direction sets a limit on unambiguously measurable whole-plane displacement. Typically, fringe pitch dictates the limit of maximum detectable displacement, and thus to be able to capture larger deformation from the earlier state, coarser fringe pitch is required to be projected; while this adversely affects the resolution of measurement system. Hence, there is a need to develop a fringe projection system which has capability for whole-plane displacement without affecting the resolution and/or necessitating higher temporal-sampling. Circular Fringe Projection (CFP) technique is proposed in the second part of the thesis as a novel solution to address the above issues. CFP technique offers additional advantage of relaxing the temporal resolution requirements of the imaging system by decoupling the maximum measurable deformation rate and the frame rate of camera. A new image analysis method is also developed to extract the underlying phase distribution of the recorded circular-fringe patterns, as the conventionally used single-frame linear-fringe analysis methods are incompetent at demodulating the circular fringes. Experimental results obtained in 3D shape measurement and whole-field out-of-plane displacement measurements of a deforming object reported in this thesis, not only confirms the ability of the proposed CFP technique in overcoming the shortcomings of the widely used linear-fringe projection technique, but also its suitability for deployment in ballistic-impact measurements.
97

Interpretando a linguagem figurada: um estudo das crônicas de Martha Medeiros

Souza, Aline Pereira de [UNESP] 27 February 2013 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:26:49Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-02-27Bitstream added on 2014-06-13T18:30:41Z : No. of bitstreams: 1 souza_ap_me_arafcl.pdf: 1139664 bytes, checksum: d356853f9d85c5a518736fd94a148442 (MD5) / Martha Medeiros é uma grande cronista contemporânea que escreve, normalmente, sobre temas cotidianos, que envolvem muitas vezes reflexões acerca do comportamento humano. É uma autora muito conhecida e muito citada em vários blogs e, inclusive, nas redes sociais, que têm sido grandes divulgadoras e formadoras de opinião. Os livros publicados por ela quase sempre figuram nas listas dos livros mais vendidos e por diversas vezes recebem indicações a prêmios literários, que são, por vezes, recebidos por ela. Esses foram alguns dos fatores que inicialmente motivaram a proposta desse trabalho: verificar o que há em seus textos que exerce atração em leitores de perfis tão heterogêneos. Um dos recursos mais utilizados por ela é o da projeção de histórias sobre histórias, as parábolas e também outros tipos de projeção, como a metáfora e a metonímia. Esta dissertação tem o objetivo, pois, de descrever esses processos de projeção a partir das modernas ferramentas da linguística cognitiva. O corpus do trabalho é composto de textos de seus dois últimos livros de crônicas: Doidas e Santas (2008) e Feliz por nada (2011). Partindo de fatos cotidianos, Martha apresenta várias reflexões acerca da vida e expressa opiniões a respeito de diversos assuntos. Na análise, foi dada especial atenção às metáforas e metonímias presentes nos textos, que são formas de projeção muito utilizadas, e que, muitas vezes, também são responsáveis pela transmissão da mensagem pretendidas pela autora. Investigaram-se, também, quais “estratégias” linguísticas estão presentes nos textos e que fazem com que eles se tornem populares entre os leitores. Além disso, procurou-se verificar de que outros mecanismos a autora se utiliza para defender seus pontos de vista acerca dos assuntos que trata; qual o efeito que esses mecanismos exercem no leitor... / Marta Medeiros is an important contemporary chronicler. She usually writes about everyday themes, which mostly involves reflections about human behavior. She is a well-known author, quoted in several blogs and also on social networks, which undoubtedly spread and form opinions. The books published by Medeiros are almost always on the best-seller lists and often receive indications to literary awards, which are, sometimes, received by her. These were some of the reasons which initially motivated the purpose of this research: to check what there is in her texts that attracts this range of heterogeneous readers. In order to conduct this study, concepts of the Modern Cognitive Linguistics, which study the great ability of the human brain to perform projections, were used. Projections are an ability believed to be a fundamental part of the human cognition to our survival. It is known that, due to projections, we can use literary texts not only as entertainment while reading, but also, in some situations, to educate, moralize and persuade. The corpus of this research is made of chronicles from Medeiros’s last two chronicle books: “Doidas e Santas” (2008) and “Feliz por nada” (2011). By writing about everyday facts, Martha presents many reflections about life and, when expressing opinions, she uses parables, metaphors and metonymies. It was judged important to verify and understand the processes of projection and the parables used in the chronicles, intending to visualize their persuasive effects. Moreover, special attention was given to metaphors and metonymies present in the texts, which are widely used in projection, and also very often responsible for transmitting the author’ intended messages. Linguistic “strategies” present in the texts, which make them popular among the readers, were also investigated. Furthermore, other mechanisms... (Complete abstract click electronic access below)
98

A Comparative Radiographic Investigation of Facial Projection in Anthropoid Primates

January 2014 (has links)
abstract: Facial projection--i.e., the position of the upper face relative to the anterior cranial fossa--is an important component of craniofacial architecture in primates. Study of its variation is therefore important to understanding the bases of primate craniofacial form. Such research is relevant to studies of human evolution because the condition in Homo sapiens--in which facial projection is highly reduced, with the facial skeleton located primarily inferior (rather than anterior) to the braincase--is derived vis-à-vis other primates species, including others in the genus Homo. Previous research suggested that variation in facial projection is explained by: (1) cranial base angulation; (2) upper facial length; (3) anterior cranial base length; (4) anterior sphenoid length; and/or (5) anterior middle cranial fossa length. However, previous research was based on taxonomically narrow samples and relatively small sample sizes, and comparative data on facial projection in anthropoid primates, with which these observations could be contextualized, do not currently exist. This dissertation fills this gap in knowledge. Specifically, data corresponding to the hypotheses listed above were collected from radiographs from a sample of anthropoid primates (N = 37 species; 756 specimens) . These data were subjected to phylogenetically-controlled multiple regression analyses. In addition, multivariate and univariate models were statistically compared, and the position of Homo sapiens relative to univariate and multivariate regression models was evaluated. The results suggest that upper facial length, anterior cranial base length, and, to a lesser extent, cranial base angle are the most important predictors of facial projection. Homo sapiens conforms to the patterns found in anthropoid primates, suggesting that these same factors explain the condition in this species. However, a consideration of the evidence from the fossil record in the context of these findings suggests that upper facial length is the most likely cause of the extremely low degree of facial projection in Homo sapiens. These results downplay the role of the brain in shaping the form of the human cranium. Instead, these results suggest that reduction in facial skeleton size--which may be due to changes in diet--may be more important than previously suggested. / Doctoral Dissertation Anthropology 2014
99

Transcriptional Controls over Neocortical Projection Neuron Identity and Connectivity

Woodworth, Mollie Ann 15 February 2016 (has links)
The complex and sophisticated circuitry of the neocortex is assembled from an extraordinarily diverse repertoire of neuronal subtypes that reside in distinct functional areas. In recent years, a number of key regulators over neocortical projection neuron subtype and area specification have been identified. It is becoming increasingly clear that these regulators function within a highly-interconnected network, acting in parallel, synergistically, and cross-repressively to orchestrate cortical development. Moreover, an emerging understanding of cortical development has revealed that subtype and area identity are intimately interrelated, and that specification occurs based on several sequential molecular decision points. Although great strides have been made in recent years toward understanding molecular controls over neocortical projection neuron development, many important controls remain to be discovered, and mechanisms by which recently-identified regulators act to delineate subtype and area identity are not well understood. In this dissertation, I characterize functions of two zinc finger transcription factors, Ctip2 and Ctip1, in postmitotic projection neuron subtype and area identity acquisition, using in vivo gain- and loss-of-function approaches in the mouse. I find that Ctip2, known for several years as a central functional control over corticospinal motor neuron (CSMN) terminal differentiation and connectivity, is required both cell-autonomously (within CSMN) and non-cell-autonomously (within striatal medium-sized spiny neurons that surround CSMN axons traveling in the internal capsule) for CSMN to achieve proper connectivity with the spinal cord. In addition, I find that Ctip1, a transcription factor not previously functionally investigated in neocortical development, is a novel control over 1) corticothalamic and callosal projection neuron development and projection neuron migration; and 2) postmitotic area identity acquisition and the formation of sensory maps. Taken together, these results reveal previously unknown functions of Ctip1 in neocortical development, and novel sites of action for Ctip2 control over CSMN connectivity. Ctip1 and Ctip2 are transcriptional controls over the postmitotic specification of neocortical projection neuron subtype and area identity, and over projection neuron connectivity with distant targets.
100

Videomapping jako rozrůstající se fenomén / Videomapping as a growing phenomenon.

Melichárková, Kristýna January 2015 (has links)
This thesis deals with the use of videomapping projections in the advertising industry. The subject of this thesis is videomapping, use of videomapng currently and the reflection of using in the future. The partial aim is to introduce the concept of videomapping process and the creation of individual projections. The benefit of this work is to compare videomappings advertisement and static advertisement on a concrete example, in the campaign Štědrá dovolená 2016. Work is supplemented by examples of videomapping´s screenings, which were held in various places, projected on different subjects and for different purposes. The conclusion presented arguments supporting the use videomapping ads in the future.

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