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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.
71

Regularities in the Augmentation of Fractional Factorial Designs

Kessel, Lisa 03 May 2013 (has links)
Two-level factorial experiments are widely used in experimental design because they are simple to construct and interpret while also being efficient. However, full factorial designs for many factors can quickly become inefficient, time consuming, or expensive and therefore fractional factorial designs are sometimes preferable since they provide information on effects of interest and can be performed in fewer experimental runs. The disadvantage of using these designs is that when using fewer experimental runs, information about effects of interest is sometimes lost. Although there are methods for selecting fractional designs so that the number of runs is minimized while the amount of information provided is maximized, sometimes the design must be augmented with a follow-up experiment to resolve ambiguities. Using a fractional factorial design augmented with an optimal follow-up design allows for many factors to be studied using only a small number of additional experimental runs, compared to the full factorial design, without a loss in the amount of information that can be gained about the effects of interest. This thesis looks at discovering regularities in the number of follow-up runs that are needed to estimate all aliased effects in the model of interest for 4-, 5-, 6-, and 7-factor resolution III and IV fractional factorial experiments. From this research it was determined that for all of the resolution IV designs, four or fewer (typically three) augmented runs would estimate all of the aliased effects in the model of interest. In comparison, all of the resolution III designs required seven or eight follow-up runs to estimate all of the aliased effects of interest. It was determined that D-optimal follow-up experiments were significantly better with respect to run size economy versus fold-over and semi-foldover designs for (i) resolution IV designs and (ii) designs with larger run sizes.
72

Le pli : Deleuze entre Leibniz et le Baroque / The fold : Deleuze between Leibniz and the Baroque

D'aurizio, Claudio 15 April 2019 (has links)
Cette étude de la pensée de Gilles Deleuze (1925-1975) trouve son origine dans la confrontation avec un texte et un concept qui nous semblent des objets féconds de réflexion. Le pli. Leibniz et le baroque (1988) est la dernière des grandes monographies que Deleuze consacre aux « intercesseurs » de sa pensée. Elle constitue une relecture compliquée et labyrinthique à la fois de l’œuvre de Gottfried Wilhelm von Leibniz (1646-1716) et de la période baroque. Plus qu’une interprétation, elle est le théâtre où apparaît un nouveau concept destiné à jeter, comme dans un après-coup, une lumière inédite sur l’œuvre entière de Deleuze : le pli. Ce dernier, loin de représenter un escamotage interprétatif, traverse sa pensée dans toute sa durée, tout en émergeant seulement vers la fin des années 80, dans la phase finale de son itinéraire intellectuel, comme le fait une vague parcourant sous le niveau de l’eau tout l’océan pour s’élever juste en proximité du littoral. Le pli paraît dans Différence et répétition (1968) et réapparaît dans Foucault (1986) ; mais il est réellement thématisé et développé avec référence à Leibniz, le penseur qui a plus que quiconque déçu et exalté Deleuze. Notre but est de démontrer comment le pli est ce concept en mesure d’exprimer le projet philosophique deleuzien dans son intégralité. En d’autres termes, le pli est le concept de Deleuze. Dans sa formulation nous pouvons retrouver tous les problèmes majeurs de sa pensée : la relation entre différence et répétition, le statut du sujet et de l’objet, la construction du plan d’immanence, la définition de l’art, de la science et de la philosophie et leur interaction. / The subject of my thesis is the concept of “fold” in the work of Gilles Deleuze, as it emerges in the late 80’s. My purpose is to show that the concept of fold can summarise the entirety of Deleuze’s philosophical project. As a matter of fact, its formulation allows to address all of the most important questions of his thought, and to adopt a different approach on the discussion and the solution of some philosophical problems, such as the theme of the subject and Deleuze’s conception of philosophy as a “creation of concepts”. By doing that, I try to follow and underline the several implicit references and the hidden theoretical pattern which compose the text of The Fold. Leibniz and the Baroque (1988). My work is composed of five chapters. The first one has an introductive character and consists of a reflexion on Deleuze’s philosophical reading method, which we define as “anamorphic”. The second chapter focuses on the presence of Leibniz in Difference and repetition (1968) and on the relevance of his thought in the creation of Deleuzes’ philosophical terminology. The third one is titled “A thousand folds”, paraphrasing the name of another work of Deleuze and Guattari. There I try to reconstruct the several theoretical lines that compose the concept of fold; furthermore, I try to underline the philosophical multiplicity of this concept. The fourth chapter focuses on the Baroque, which plays a fundamental role in Deleuze’s argumentations. Here I retrace his ideas about infinity and folding during the Baroque era. Then, I try to confront his theory with Walter Benjamin and Jacques Lacan’s lectures of Baroque. The last chapter deals with the concept of neobaroque.
73

Anatomia e morfogênese da margem do manto da vieira Nodipecten nodosus (L. 1758) (Bivalvia: Pectinidae) / Anatomy and morphogenesis of the mantle margin in the scallop Nodipecten nodosus (L. 1758) (Bivalvia: Pectinidae)

Audino, Jorge Alves 10 November 2014 (has links)
O atual conhecimento sobre a margem do manto em moluscos bivalves é extenso, incluindo informações sobre morfologia, função e diversidade. Bivalves da família Pectinidae, também conhecidos como vieiras, possuem complexa margem palial, organizada em três pregas, incluindo olhos e tentáculos. Questões acerca do desenvolvimento da margem do manto em bivalves continuam amplamente incompreendidas, assim como a relação entre características paliais ao longo dos diferentes estádios do ciclo de vida. Neste contexto, a presente investigação utilizou a espécie de vieira Nodipecten nodosus como modelo para compreensão da morfogênese da margem palial em Pectinidae, com ênfase na origem e diferenciação das pregas paliais e estruturas associadas. Para contemplar esses objetivos, espécimes em diferentes estádios de desenvolvimento larval e pós-metamórfico foram analisados por meio de técnicas integradas de microscopia (i.e., histologia, microscopia eletrônica de varredura e transmissão, e imunocitoquímica aplicada à microscopia confocal). Inicialmente, a margem palial em larvas véliger de N. nodosus não é pregueada, porém, ao longo do desenvolvimento, dois processos de evaginação são determinantes na formação das pregas paliais. O primeiro ocorre no estádio de pedivéliger, originando as pregas externa e interna, bem como o sulco do perióstraco. O segundo ocorre após a metamorfose, sendo responsável pela origem da prega palial mediana a partir da porção interna da prega interna. Os sistemas muscular e nervoso da margem palial têm origem durante o período larval, tornando-se amplamente desenvolvidos posteriormente. Estruturas associadas, como tentáculos e olhos paliais, são formadas apenas após a metamorfose, e compõem a complexa condição final da margem do manto em Pectinidae. Os diferentes tipos tentaculares possuem desenvolvimento e anatomia similar, entretanto diferem quanto ao tamanho, tipo de musculatura, organização ciliar e presença de células glandulares. Os olhos paliais em formação diferenciam-se gradualmente em sentido proximal-distal, essas características morfológicas sugerindo um nível simples de fotopercepção direcional como condição inicial. Os dados aqui apresentados para N. nodosus permitiram propor um modelo geral para o desenvolvimento da margem palial em Pectinidae, além de contribuir para o entendimento da morfogênese dessa região em Bivalvia / Current knowledge of the bivalve mantle margin is extensive, covering several aspects of its morphology, function and diversity. Bivalves from the family Pectinidae, also known as scallops, bear three pallial folds at the mantle margin, including complex structures, such as tentacles and eyes. The development of the bivalve mantle margin is still poorly understood, the morphogenesis and functional anatomy of mantle margin features during developmental stages being enigmatic. The present investigation used the scallop Nodipecten nodosus (L. 1758) as a model species to understand mantle margin morphogenesis in the Pectinidae, with emphasis on the origin and differentiation of pallial folds and associated pallial structures. To achieve these goals, specimens from larval and postmetamorphic stages were thoroughly analyzed by means of integrative microscopy techniques (i.e., histology, scanning and transmission electron microcopy, and immunocytochemistry combined with confocal microscopy). In veliger larvae of N. nodosus, the mantle margin is initially unfolded, two folding processes being crucial for pallial fold establishment during further development. The first one occurs by the pediveliger stage, forming the outer and inner folds, as well as the periostracal groove. The second folding process takes place after metamorphosis and is responsible for the formation of the middle pallial fold from the inner region of the inner mantle fold. The emergence of muscular and nervous systems in the mantle margin occurs early during development, at the larval stage. Associated pallial structures, including tentacles and eyes, develop only after metamorphosis, and contribute to the complex final condition of the mantle margin in Pectinidae. Although different tentacular types have similar development and anatomy, they differ in size, muscle type, ciliary organization, and gland cells distribution. Developing pallial eyes exhibit gradual differentiation in a proximal-distal direction, and their morphological features suggest a simple level of directional photoreception as the initial ocular condition in juveniles. The present investigation conducted with N. nodosus provided a general model to understand mantle margin development in the Pectinidae, as well as insights into the morphogenesis of this region in the Bivalvia
74

Desenquadramentos no novíssimo cinema brasileiro : o Fora de Campo como Dobra da Mise-en-Scène nos filmes de André Novais

Diniz, Felipe Maciel Xavier January 2018 (has links)
Esta tese se mostra como um estudo sobre a natureza da relação entre o fora de campo e a mise-en-scène no contexto do Novíssimo Cinema Brasileiro. Tendo como base para um estudo de caso a experiência cinematográfica do diretor mineiro André Novais, nosso intuito foi o de compreender, nos termos de um plano de imanência, os movimentos que amparam as discussões sobre as encenações e seu fora de campo. Para aprofundarmos o pensamento sobre uma dada indissociabilidade entre as instâncias do fora de campo e da mise-en-scène nos filmes de Novais, aplicamos a ideia da dobra, que, atualizada por Deleuze, opera na coexistência entre o dentro e o fora ao problematizar um espaço que se configura indiscernível. A partir daí, investimos na tese dos desenquadramentos, trazida por Deleuze no livro A Imagem Movimento (2009), e suas reverberações em relação às dimensões relativa e absoluta do fora de campo. Torna-se, portanto, necessário aproximar tais aspectos a determinadas concepções formais atreladas aos filmes que estudamos. É então que apostamos em figuras de linguagem, como as metonímias e as dimensões intertextuais e paratextuais, para atestar a presença de um fora de campo relativo, que nos traz exemplos mais concretos e aplicações mais diretas em relação ao espaço fílmico, e refletimos sobre as desnaturalizações e as indecidibilidades para pensar a porção de uma dimensão absoluta do fora de campo, esta mais ligada a uma duração do todo do universo e a um discurso indireto livre. Cabe assinalar que o estudo de caso aplicado à filmografia de André Novais é inserido em um contexto cinematográfico específico: o Novíssimo Cinema Brasileiro. Torna-se, assim, fundamental estabelecermos uma discussão sobre as particularidades de suas concepções estéticas e de mise-en-scène. Na esteira desse movimento, chegamos à compreensão do aspecto documental que invade tal contexto cinematográfico e que é problematizado a partir do deslocamento de um real representado para a sua realização no âmbito simbólico. A partir das teorias lançadas por Bazin, Metz, Badiou e Zizek, chegamos a um real entendido como fantasma, e não como referente. Ao alcançarmos o cerne de uma linguagem aplicada a determinadas formas fílmicas, encontramos a expressão de uma encenação desdramatizada, ligada aos aspectos minimalistas e hiper-reais e à produção de personagens da recusa, enfatizados a partir da incapacidade de adequação às identidades e aos modelos. Tais variáveis nos ajudam a refletir não só sobre as particularidades de uma mise-en-scène, mas também sobre os movimentos disruptivos e desconstrutivos do cinema. / This doctoral thesis studies the nature of the relationship between the out-of-field and the mise-en-scène in the context of the Newest Brazilian Cinema (Novíssimo Cinema Brasileiro). Taking the mineiro director André Novais’ cinematographic experience as foundation for a case study, we aimed to understand, in terms of a plane of immanence, the movements supporting the discussion about staging and its respective out-of-field. In order to deepen our thoughts on a certain inseparability between the out-of-field and the mise-en-scène in Novais' movies, we adopt the concept of “fold”, which, updated by Deleuze, establishes itself in the coexistence between inside and outside, while problematizing an indiscernible space. Thereon, we address the thesis of the unframing, brought forward by Deleuze in his book The Movement-Image (2009), and its reverberations around the relative and the absolute aspects of the out-of-field. It was therefore imperative to approach such aspects in relation to certain formal conceptions attached to the movies we study. That is where we employ figures of speech such as the metonymy and the intertextual/paratextual dimmensions, so that we were able to attest to the presence of a relative out-of-field, which brings us many concrete examples and direct applications in relation to the filmic space. Furthermore, we also considered denaturalizations and undecidabilities to conceive an absolute dimmension of the out-of-field, associated with the free indirect discourse and with a duration which is immanent to the whole universe. We should point out that the case study about André Novais’ filmography inserts itself in a specific cinematographic context: the Newest Brazilian Cinema. It was thus fundamental that we stablished a debate about the peculiarities of its mise-en-scène and its aesthetic conceptions. Approaching this movement, we reach an understanding about the documentary aspect which overruns such cinematographic context and which is examined as through the displacement of a represented “Real” up to a realization in the symbolic realm. Aimed with theories laid by authors such as Bazin, Metz, Badiou and Zizek, we end up conceiving the Real as ghost, instead of referent. Achieving the kernel of a language applied to certain filmic forms, we discover the expression of a de-dramatized staging, characterized by minimalist and hiper-realist aspects and by the production of “refusal characters”, unable to conform themselves to predefined identities and models. Such variables help us reflect not only upon mise-en-scène peculiarities, but also upon disruptive and deconstructive cinema movements.
75

Modèles thermo-géométriques et leurs applications dans la construction de coupes équilibrées-Exemples de Taïwan et des Appalaches / Thermo-geometric models and their applications in the construction of balanced cross-section –Examples from Taiwan and Appalachian

Mansour, Mohannad 26 September 2013 (has links)
Des modèles géométriques ont été proposés pour reconstruire la géométrie de plis associés aux rampes (par exemple pli sur flexure de faille), en identifiant en particulier la profondeur de niveau de décollement et le déplacement total sur la rampe. Ces méthodes de reconstruction géométrique sont appliquées pour des plis partiellement érodés. Au cours de l'érosion, le cut-off de la rampe peut être érodé et, par conséquent, le déplacement sur la rampe est difficile à quantifier. Dans cette thèse, nous développons onze modèles thermo-géométriques. Les modèles combinent les données géométriques et les données d’enfouissement pour proposer une évolution cinématique d’un pli avec cut-off érodé. Nous supposons que la mise en place d'une unité tectonique produit une anomalie thermique dans le mur de la faille, et que cette anomalie thermique pourrait indiquer une épaisseur de bloc chevauchant. Les modèles fournissent une estimation de la profondeur de décollement et le déplacement total sur une rampe érodée, qui ne dépend pas de taux d’érosion. Dans le cas de chevauchements actifs, les modèles proposent un taux de déplacement et un âge de l'initiation de la faille en fonction de taux d'érosion. Ces données sont utilisées pour proposer un développement cinématique de coupes érodées. Nous appliquons les modèles sur les plis érodés et actif à Taiwan dans les zones de Choshui et Miaoli. On propose des coupes régionales équilibrées en utilisant la technique de modélisation directe. Dans la section Choshui, nous proposons un niveau de détachement de ~5 km à ~14 km, marquée par deux sauts successifs de rampes de ~5 km and ~4 km. En supposant un taux d'érosion à 4 mm/an, l'âge de l’initiation de chevauchement active est entre 3,3 Ma dans la partie intérieure de prisme (Chevauchement de Tili) à 0,9 Ma dans la partie extérieur (Chevauchement de Chelungpu). Le raccourcissement totale sur la coupe de Choshui est ~100 km et le taux de déplacement calculé est ~1 cm/an. Pour tester nos modèles thermo-géométriques dans une chaîne plissée inactive, on applique nos modèles sur les plis érodés associés aux failles de Pine Mountain et Jones Valley dans la chaîne plissée des Appalaches. L'application des modèles thermo-géométriques nous permet d’estimer une quantité de déplacement sur les deux failles et expliquer de manière satisfaisante l'anomalie thermique dans le mur des failles de Pine Mountain et Jones Valley. Afin d'améliorer la description de l’anomalie thermique qui se développe dans le soubassement des failles, on a étudié l'évolution des minéraux magnétiques des roches argileuses le long de quatre sections dans la chaîne plissée à Taiwan. On a remarqué que la greigite (Fe3S4) domine l'assemblage magnétique dans les roches enfouies à moins à moins de de 70°C. La magnétite (Fe3O4) se développe pour des températures d’enfouissement de ~50°C et domine l’assemblage magnétique jusqu'à ~350° C. A partir ~300°C, la pyrrhotite monoclinique (Fe7S8) se développe aux dépens de la magnétite, et à ~350°C, la magnétite n'est plus détecté. Ces résultats peuvent être utilisés en complément d'autres géothermomètres pour identifier les anomalies thermiques dans une gamme de de 50-70°C et de 300-350°C où les caractéristiques des minéraux magnétiques sont identifiées / Geometric models have been proposed to account satisfactorily for ramp-related folds (e.g. fault-bend fold), identifying in particular detachment depth and total shortening. These methods of geometric reconstruction are applied on partially eroded folds. During erosion, the fault cut-off may be removed and as a result, the displacement is difficult to quantify. In this thesis, we develop 11 thermo-geometric models combining geometric description of folds and burial data to propose kinematic evolution of folds with eroded cut-offs. We assume that the emplacement of a tectonic unit will result in a thermal anomaly in the footwall, and that this thermal anomaly might indicate a thickness of the overriding unit. The models provide an estimation of the detachment depth and the total shortening on an eroded ramp, independent of the erosion rate. In the case of active thrusts, the models provide an estimation of the slip rate and the age of the initiation of the thrust as a function of the erosion rate. These data are used to unravel the kinematic development of eroded cross-sections. We apply the models on eroded folds from Taiwan underlined by active thrusts in the Choshui and Miaoli sections. We propose regional balanced cross-sections using forward modeling technique. In the Choshui section, we propose a detachment profile with a depth between ~ 5 km and ~ 14 km, marked by two steps of ~ 5 km. Assuming erosion rate at 4 mm/a, the age of initiation of the active thrusts is ranging from 3.3 Ma inward (Tili thrust) to 0.9 Ma outward (Chelungpu thrust). The total shortening from the whole section is ~100 km and the calculated slip rate is about 1 cm/a. To test our models in a non-active fold-and-thrust belt, we study eroded folds associated to the Pine Mountain thrust and Jones Valley thrust from the Appalachian belt. The application of the thermo-geometric models provides a value of the total shortening and explains satisfactorily the thermal anomaly in the footwall of the Jones Valley thrust. In order to improve the description of the thermal anomaly, we have studied the evolution of magnetic minerals of argillaceous rocks in four sections from the Taiwan thrust belt. We found that the iron sulfide greigite (Fe3S4) is dominating the magnetic assemblage in the less buried rocks (<70°C). The magnetite (Fe3O4) develops at burial temperature of ~50°C and is dominating the magnetic assemblage up to ~350°C. By ~300°C, the monoclinic pyrrhotite (Fe7S8) develops at the expense of magnetite, and at ~350°C, the magnetite is no longer detected. These results can be used complementary to other geothermometers to identify thermal anomalies in the range 50-70°C and 300-350°C where characteristic magnetic minerals are identified
76

Behavioral Finance - Prospect Theory a vliv typu vysokoškolského vzdělání na čtyřdílné chování / Behavioral Finance - Prospect Theory and impact of type of college education on the four-fold pattern

Karamonová, Petra January 2011 (has links)
Thesis deals with Prospect Theory and with its findings when making decisions under risk which is called four-fold pattern. In theoretical part is shortly mentioned the field of Behavioral finance and further described original Prospect Theory and also its modified version called Cumulative Prospect Theory. The main goal of the practical part is to confirm on the basis of questionnaire between different kinds of college graduates the four-fold pattern, identify between 3 segments differences and make the final conclusion whether the type of college education has an impact on four-fold pattern.
77

A influência da emissão sonora nos constituintes da lâmina própria da prega ventricular / The influence of the sound emission on the lamina propria of the ventricular fold

Armani, Andre 18 December 2015 (has links)
As pregas vocais (PV) são estruturas únicas, altamente especializadas na vibração para a produção sonora. Em grande parte, decorrente da estruturação em camadas da lâmina própria (LP). Essa estruturação não está presente ao nascimento, somente após anos de uso vibratório e fonatório da PV é que a LP está finalmente estruturada. As pregas ventriculares (PVT) não são, habitualmente, estruturas vibratórias na produção sonora, e possuem a LP menos organizada em estratos, sendo menos especializadas para a vibração. Até o presente momento, não se tem conhecimento do que ocorre com os constituintes da LP de PVTs de pessoas que as utilizam como fonte produtora de voz. No presente estudo, foram comparados os constituintes colágenos e as fibras elásticas da LP de PVTs de indivíduos que as utilizam como principal fonte vibratória na produção de voz com o grupo controle. Foram selecionados seis indivíduos que utilizavam pelo menos uma das PVTs como fonte de vibração para a produção sonora por ao menos seis anos. Delas, colheu-se pequeno fragmento (0,5 cm2), que após processamento histológico, as fibras colágenas foram coradas com Picrosirus Red e as fibras elásticas com Weigert resorcina-fucsina. Foram obtidas 54 imagens da camada mais superficial da LP de cada PVT para cada coloração. Após a aquisição das imagens, as fibras colágenas tipo I e tipo III, colágenas totais e fibras elásticas foram quantificadas utilizando-se o software Image-Pro Plus, e comparadas com as PVTs dos controles. A análise estatística foi realizada por meio do teste T de Student para amostras não pareadas. A porcentagem de colágeno total na camada mais superficial da LP de PVT utilizada como fonte vibratória para a produção de som foi significativamente maior em relação aos controles. O mesmo ocorreu com a quantidade de colágeno tipo I. Não houve diferenças na quantidade de colágeno tipo III e de fibras elásticas. Como conclusão, pode-se afirmar que a utilização da PVT como fonte vibratória produtora de som leva ao aumento da quantidade de fibras colágenas totais e do tipo I na camada mais superficial da sua LP / The vocal folds (VF) are unique structures, highly specialized in vibrating for sound production. This specialization is mainly due to a layered structure of the lamina propria (LP). This layered structure is not present at birth, and develops only after a several years of phonation. The LP of the mature vocal fold consists of three layers. The ventricular folds (VTF) are not originally vibrating structures for sound production, and in its LP the layers are poorly organized. It is not known what happens to the constituents of the LP in the VTF in subjects that use VTF vibration as a source of voice production. In the present study, the distribution and quantity of collagen and elastic fibers of the lamina propria from VTF of patients that use it as the main source of vibration for voice production were compared with the VTF from control subjects. Six individuals that used at least one of the VTF as source of vibration for sound production for minimum of six years were selected. A small fragment of VTF (0.5 cm2) used as vibration source of sound production was collected from each subject. The samples were processed for histological analysis. Collagen fibers were stained with Picrosirus Red and elastic fibers were stained with Weigert\'s Resorcin-Fuchsin. A total of 54 images were obtained from the superficial layer of the LP from each VTF for each stain. After image acquisition, collagen type I, III, total collagen and elastic fibers were quantified and compared with the VTF from the control group. Quantification was done using Image-Pro Plus software. Statistics were performed using an unpaired Student T test. The amount of total collagen in the most superficial layer of LP when the VTF was used as the source of vibration for the production of sound was significantly higher when compared to controls. The same result was seen for the amount of type I collagen in both groups. There was no difference in the quantity of type III collagen and elastic fibers between the two groups. Vibration of the VTF as a source of sound, for at least six years, leads to an increase in the amount of total collagen fibers and an increase in type I collagen, but does not increase the amount of type III collagen and elastic fibers in the most superficial layer of LP. These results may help elucidate the unique development of the lamina propria of the vocal fold
78

Sistemática e tafonomia de microfósseis vasiformes neoproterozoicos do Brasil e seu significado paleoecológico e filogenético. / not available

Soares, Luana Pereira Costa de Morais 09 October 2017 (has links)
Esta pesquisa investigou microfósseis neoproterozoicos em forma de vaso (\"vase-shaped microfossils - VSMs\") da Formação Urucum (Grupo Jacadigo) e Formação Bocaina (Grupo Corumbá), ambas inseridas na Faixa Paraguai Sul, Brasil. Estes microfósseis foram comparados a outras ocorrências neoproterozoicas no mundo. O objetivo foi contribuir com o conhecimento de aspectos paleobiológicos, evolutivos e bioestratigráficos relacionados ao aparecimento de eucariontes unicelulares tecados em ecossistemas anteriores ao surgimento dos metazoários. Os VSMs podem ser atribuídos a quitinozoários, tintinídeos e foraminíferos, porém, características diagnósticas importantes apontam o grupo Amoebozoa como afinidade biológica mais próxima. A variedade morfológica e composicional observada em VSMs neoproterozoicos, inclusive nos exemplares brasileiros, documenta a mais antiga diversificação da vida unicelular eucariótica, presumivelmente heterotrófica, preservada no registro geológico. As diferentes fácies sedimentares contendo VSMs fornecem informações valiosas sobre fatores ambientais que podem ter sido importantes na diversificação bem como no seu possível desaparecimento entre o Neoproterozoico e o Mesozoico. Além disso, a ampla distribuição e variedade desses microfósseis sugerem uma possível aplicação bioestratigráfica. Microscopia petrográfica (MP) e Eletrônica de Varredura (MEV), Espectrometria de Energia Dispersiva de Raios X (EDS), Microscopia Confocal (MC), Espectroscopia Raman (ER), Catodoluminescência (CL) além de técnicas geoquímicas e geocronológicas foram aplicadas para caracterizar a composição e morfologia dos microfósseis, bem como para a rocha encaixante, visando inferir a natureza e paleoecologia dos organismos responsáveis pelas produção das tecas e o ambiente em que viveram, se diversificaram e desapareceram. / This research investigated vase-shaped microfossils (VSMs) from the Urucum Formation (Jacadigo Group) and Bocaina Formation (Corumbá Group), both inserted in the Southern Paraguay Fold Belt, Brazil. These microfossils were compared to other neoproterozoic occurrences in the world. The aim was to contribute to the knowledge of paleobiological, evolutionary and biostratigraphic aspects related to the appearance of unicellular eukaryotes in the ecosystems that preceed the appearance of metazoans. VSMs can be attributed to quitinozoan, tintinids and foraminifera, but important diagnostic features point to the Amoebozoa group as the closest biological affinity. The morphological and compositional variety observed in neoproterozoic VSMs, including Brazilian specimens, documents the earliest diversification of eukaryotic unicellular life, presumably heterotrophic, preserved in the geological record. The different sedimentary facies containing VSMs provide valuable information about environmental factors that may have been important in the diversification as well as their possible disappearance between the Neoproterozoic to the Mesozoic. In addition, the wide distribution and variety of these microfossils suggest a possible biostratigraphic application. Petrography, Scanning electron microscopy, Confocal microscopy, Energy-dispersive X-ray spectroscopy, Raman spectroscopy, Cathodoluminescense, besides geochemical and geochronological techniques, were applied to characterize the composition and morphology of the microfossils, as well as for the host rock, in order to infer the nature and paleoecology of the organisms responsible for the production of the test and the environment in which they lived, diversified and probably disappeared
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Origami-Based Design of Fold States and Stability

Avila, Alex 01 December 2018 (has links)
Origami is a potentially elegant and powerful source of inspiration for many engineering designs. The viable shapes (fold states) of a single device allow it to perform multiple, seemingly contradictory, functions. The fold state is a large factor in the device's performance, but there are challenges in selecting and maintaining those fold states. In this thesis we analyze existing concepts for overcoming these challenges. Those concepts are compared with those that occur in origami-based devices. From this analysis fundamental gaps were identified, specifically, shortcoming in the terminology used to refer to (1) non-flat origami states and (2) sets of facets and creases. Likewise we found a need for a comprehensive categorization method of fold states. Fold states are divided into seven types based on the set of fold angles they contain: U, P, F, UP, UF, PF, and UPF. The origami-based devices are analyzed based on their functional fold states, showing an emphasis on P and PF fold states. The fold states and their functions are tabulated. We demonstrate the table as a tool in an origami-based design method. Selecting fold states for an application is just the first step for effective use of origami. Once selected, the origami fold state must be maintained during use to perform its functions. This thesis also outlines the Origami Stability Integration Method (OSIM) for integrating a wealth of stability techniques. These techniques are categorized and analyzed to assist designers in selecting a technique for a device's application. Both methods, the fold-state selection method and the OSIM, are demonstrated in designing an origami-based ballistic barrier. The barrier is designed to stow in a compact fold state and deploy to a partially folded state to provide protection during armed conflicts. Quick deployment and a stable structure make the barrier a valuable example of origami-based design, demonstrating these two methods in addressing some of origami's design challenges.
80

Review of Drawing on America’s Past: Folk Art, Modernism, and the Index of American Design

Tolley, Rebecca 01 March 2003 (has links)
No description available.

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