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Středoanglické lexikální inovace domácího původu (1200-1500) ze slovotvorného hlediska / Native lexical innovations in Middle English (1200-1500): a word-formation perspectiveRůžičková, Eliška January 2018 (has links)
This thesis examines suffixation in Middle English in the periods 1200-1299 and 1300-1399. More specifically, the work is focussed on nominal coinages of native origin only, formed with the suffixes -ness, -head / -hood, -ship and -dom, where the aim is to observe their productivity in time. In the theoretical part, we explore the contribution of external (socio-political) and internal (typological and word-formational) factors to changes in the English language, including word-formation processes. Our hypothesis is that suffixation as a word-formation process will continue strongly, despite the ongoing language-internal changes and the overwhelming influx of foreign words. Data for this research was collected from The Oxford English Dictionary (OED) through Advance Search. The data retrieved for each suffix was considered from a morphological, structural and lexico-semantic perspective. The analyses were performed to detect changes in the behaviour of each suffix and to discover the realities attesting their productivity. Moreover, the analyses uncovered additional phenomena: types that had only one quotation (hapaxes) and competition occurring between the selected suffixes. The hapaxes were also investigated for their morphological, structural and semantic features so as to identify any common...
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Geologia da formação ferrífera do Serrote do Breu e de Alto das Pedras, Alagoas / Geology of Serrote do Breu and Alto das Pedras iron-formation, AlagoasMario Cesar Prazim Trotta 19 February 2015 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A formação ferrífera do Serrote do Breu e de Alto das Pedras localiza-se no município de Campo Grande, Estado de Alagoas e está sendo pesquisada quanto ao seu potencial como minério de ferro. Ela está inserida em um domo de embasamento arqueano no interior da Faixa Sergipana, o Domo de Jirau de Ponciano. A área de estudo é caracterizada por dois altos topográficos denominados Serrote do Breu e Alto das Pedras, sustentados pela formação ferrífera, e que representam flancos opostos de um sinformal inclinado, com direção N60W e forte mergulho para sul, e extensão total de aproximadamente 2 km. A formação ferrífera ocorre em diversas camadas intercaladas em gnaisses quartzo-feldspáticos e em rochas metamáficas. Os primeiros foram agrupados na unidade de gnaisses quartzo-feldspáticos e as últimas na suíte intrusiva máfica-ultramáfica. Na porção interior do sinformal estão quartzitos e paragnaisses agrupados na unidade metassedimentar e cortando essas unidades há uma unidade de pegmatitos. A formação ferrífera é constituída por quartzo, hematita, anfibólio e magnetita. O anfibólio é em geral cummingtonita, mas riebeckita também ocorre subordinadamente. Os teores médios de SiO2, e Fe2O3t são 43,1% e 50,7%, respectivamente, e, assim como os demais elementos maiores, são compatíveis com outras formações ferríferas do mundo. Com base na petrografia e geoquímica de elementos terras raras os gnaisses quartzo-feldspáticos foram divididos em gnaisses bandados e gnaisses com titanita. Ambos apresentam composição riolítica e trend calcio-alcalino. Já as rochas metamáficas e metaultramáficas apresentam composição basáltica a andesítica e trend toleítico completamente dissociado daquele dos gnaisses. Acredita-se que os gnaisses quartzo-feldspáticos e as rochas metamáficas e metaultramáficas tenham se formado em ambientes tectônicos totalmente distintos, com as últimas tendo se formado provavelmente intrusivas nos primeiros. / Serrote do Breu and Alto das Pedras are located in the municipality of Campo Grande, in the State of Alagoas where an iron-formation occurs. It is currently being explored for its potential for hosting an iron ore deposit. It is tectonically settled inside Jirau do Ponciano Dome, an Archean basement within Sergipano Belt. Serrote do Breu and Alto das Pedras are two topographic highs totaling 2 km in length, marked by outcrops of iron-formation which represent opposite limbs of an inclined sinformal elongated N60W and dipping steeply to the South. This iron-formation comprises of several layers intercalated with quartz-feldspathic and metamafic rocks. The former were grouped into quartz-feldspathic gneisses unit and the latter into mafic-ultramafic intrusive suite. Quartzites and paragneisses were mapped and grouped into metasedimentary unit and all units are cross-cutted by pegmatites unit. Iron-formation is constituted by quartz, hematite, amphibole and magnetite. Amphibole is commonly cummingtonite, but riebeckite also occurs. Average grades for SiO2 and Fe2O3t are 43,1% and 50,7%, respectively, and along with other major elements, are similar to other iron-formations of the world. Considering petrographical and geochemical data, quartz-feldspathic gneisses were divided into banded gneisses and sphene-bearing gneisses although both presents rhyolitic composition and calc-alkaline trends. Metamafic and metaultramafic rocks present basaltic to andesitic composition and show a tholeiitic trend completely different from that of gneisses. It is proposed here that these distinct rocks were formed in completely different tectonic settings with the latter being probably intrusive in the former.
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Governing More than Language: Rationalities of Rule in Flores DiscoursesJanuary 2014 (has links)
abstract: This project offers an exploration of the constitution of English language learners (ELLs) in the state of Arizona as subjects of government through the discursive rationalities of rule that unfolded alongside the Flores v. Arizona case. The artifacts under consideration span the 22 years (1992-2014) of Flores' existence so far. These artifacts include published academic scholarship; Arizona's legislative documents and floor debate audio and video; court summaries, hearings, and decisions; and public opinion texts found in newspapers and online, all of which were produced in response to Flores. These artifacts lay bare but some of the discursive rationalities that have coagulated to form governable elements of the ELL student population--ways of knowing them, measuring them, regarding them, constituting them, and intervening upon them. Somehow, some way, students who do not speak English as their first language have become a social problem to be solved. ELLs are therein governed by rationalities of English language normalization, of enterprise, of entrepreneurship, of competition, of empowerment, and of success. In narrating rationalities of rule that appear alongside the Flores case, I locate some governmental strategies in how subjects conduct themselves and govern the conduct of others with the hope that seeing subject constitution as a work of thought and not a necessary reality will create a space for potentially unknown alternatives. Through this work, I'd like to make possible the hope of thinking data differently, rejecting superimposition of meaning onto artifact, being uncomfortable, uncertain, undefinitive, and surprised. With that, this work encourages potential paths to trod in the field of curriculum studies. / Dissertation/Thesis / Doctoral Dissertation Curriculum and Instruction 2014
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Geologia da formação ferrífera do Serrote do Breu e de Alto das Pedras, Alagoas / Geology of Serrote do Breu and Alto das Pedras iron-formation, AlagoasMario Cesar Prazim Trotta 19 February 2015 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A formação ferrífera do Serrote do Breu e de Alto das Pedras localiza-se no município de Campo Grande, Estado de Alagoas e está sendo pesquisada quanto ao seu potencial como minério de ferro. Ela está inserida em um domo de embasamento arqueano no interior da Faixa Sergipana, o Domo de Jirau de Ponciano. A área de estudo é caracterizada por dois altos topográficos denominados Serrote do Breu e Alto das Pedras, sustentados pela formação ferrífera, e que representam flancos opostos de um sinformal inclinado, com direção N60W e forte mergulho para sul, e extensão total de aproximadamente 2 km. A formação ferrífera ocorre em diversas camadas intercaladas em gnaisses quartzo-feldspáticos e em rochas metamáficas. Os primeiros foram agrupados na unidade de gnaisses quartzo-feldspáticos e as últimas na suíte intrusiva máfica-ultramáfica. Na porção interior do sinformal estão quartzitos e paragnaisses agrupados na unidade metassedimentar e cortando essas unidades há uma unidade de pegmatitos. A formação ferrífera é constituída por quartzo, hematita, anfibólio e magnetita. O anfibólio é em geral cummingtonita, mas riebeckita também ocorre subordinadamente. Os teores médios de SiO2, e Fe2O3t são 43,1% e 50,7%, respectivamente, e, assim como os demais elementos maiores, são compatíveis com outras formações ferríferas do mundo. Com base na petrografia e geoquímica de elementos terras raras os gnaisses quartzo-feldspáticos foram divididos em gnaisses bandados e gnaisses com titanita. Ambos apresentam composição riolítica e trend calcio-alcalino. Já as rochas metamáficas e metaultramáficas apresentam composição basáltica a andesítica e trend toleítico completamente dissociado daquele dos gnaisses. Acredita-se que os gnaisses quartzo-feldspáticos e as rochas metamáficas e metaultramáficas tenham se formado em ambientes tectônicos totalmente distintos, com as últimas tendo se formado provavelmente intrusivas nos primeiros. / Serrote do Breu and Alto das Pedras are located in the municipality of Campo Grande, in the State of Alagoas where an iron-formation occurs. It is currently being explored for its potential for hosting an iron ore deposit. It is tectonically settled inside Jirau do Ponciano Dome, an Archean basement within Sergipano Belt. Serrote do Breu and Alto das Pedras are two topographic highs totaling 2 km in length, marked by outcrops of iron-formation which represent opposite limbs of an inclined sinformal elongated N60W and dipping steeply to the South. This iron-formation comprises of several layers intercalated with quartz-feldspathic and metamafic rocks. The former were grouped into quartz-feldspathic gneisses unit and the latter into mafic-ultramafic intrusive suite. Quartzites and paragneisses were mapped and grouped into metasedimentary unit and all units are cross-cutted by pegmatites unit. Iron-formation is constituted by quartz, hematite, amphibole and magnetite. Amphibole is commonly cummingtonite, but riebeckite also occurs. Average grades for SiO2 and Fe2O3t are 43,1% and 50,7%, respectively, and along with other major elements, are similar to other iron-formations of the world. Considering petrographical and geochemical data, quartz-feldspathic gneisses were divided into banded gneisses and sphene-bearing gneisses although both presents rhyolitic composition and calc-alkaline trends. Metamafic and metaultramafic rocks present basaltic to andesitic composition and show a tholeiitic trend completely different from that of gneisses. It is proposed here that these distinct rocks were formed in completely different tectonic settings with the latter being probably intrusive in the former.
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[en] PRODUCTION AND LEXICAL PRODUCTIVITY IN JOSÉ CÂNDIDO DE CARVALHO / [pt] PRODUÇÃO E PRODUTIVIDADE LEXICAL EM JOSÉ CÂNDIDO DE CARVALHODAVI OLIVEIRA DO NASCIMENTO 02 February 2018 (has links)
[pt] Este trabalho constitui-se num estudo morfológico sobre a questão produtividade / produção de padrões lexicais em textos literários, com o objetivo de sustentar a hipótese de que tais obras apresentam condições de produção especiais em relação a determinados padrões morfológicos de formação. A base de investigação é a obra O Coronel e o Lobisomem, de José Candido de Carvalho, já conhecida por seu teor de inovação lexical. São eleitas para análise as sufixações com –ão e –oso e a prefixação com des-, formações morfológicas que se constituem em potenciais processos de inovação lexical. Sugere-se que a utilização de tais padrões na obra não é fortuita, já que parecem representar iconicamente o discurso hiperbólico do personagem principal. De início, apresenta-se uma visão geral da morfologia lexical, quanto a seu tratamento tradicional e em relação a contribuições mais recentes, focalizando-se especialmente a questão produtividade/produção. Procede-se depois à apreciação do tratamento dado pelos estudiosos do português sobre os formativos com –ão, -oso e des-. Em seguida, são analisadas as formações encontradas na obra O Coronel e o Lobisomem. Finalmente, são apresentadas as conclusões sobre o uso que o autor faz dos padrões de formação em sua obra, os quais refletem o discurso do personagem principal, com vistas a afirmar a relevância da análise das condições de produção, ao lado da questão da produtividade, para um melhor conhecimento do léxico do português. / [en] This work is a morphologic study on the issue of lexical productivity and production in literary texts. Its main goal is to support the hypothesis that literary works present special conditions for the use of morphological formation patterns.Our investigation is based on the novel The Colonel and the Werewolf by Jose Candido de Carvalho, a work which is known for its lexical innovations. The suffixes –ão and –oso, as well as the prefix des- were chosen for our analysis, as they are the preferred morphological elements for lexical innovation in Carvalhos s work. Our results suggest that the use of these morphological patterns in the work is not fortuitous; in fact, they seem to iconically represent the hyperbolic discourse of the main character of the novel. We initially present an overview of lexical morphology, which includes both traditional approaches and recent contributions; the main focus will be on the productivity/production issue. Then, we approach the description of the suffixes –ão and –oso and the prefix desin Portuguese. Next, the lexical constructions with these elements occurring in the book The Colonel and the Werewolf are analyzed. We conclude showing that the author uses morphological patterns to reinforce the discourse of the main character of the novel. This analysis shows the relevance of the study of production conditions, in addition to productivity, for a deeper understanding of the lexicon in Brazilian Portuguese.
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Estudo geológico do potencial de exploração e produção de gás natural não convencional na bacia do Paraná: avaliação da viabilidade no abastecimento da usina termoelétrica de Uruguaiana (RS) / A geological study of the potential for exploration and production of shale gas in Paraná sedimentary basin, Brazil: viability evaluation to supply thermoelectricity generation in Uruguaiana power plant.Haline de Vasconcellos Rocha 19 February 2016 (has links)
A presente dissertação de mestrado consiste na realização de um estudo geológico acerca do potencial para exploração e produção de gás natural não convencional na Bacia do Paraná, regiões sul e sudeste do Brasil e norte do Uruguai. Com essa finalidade, foram analisadas as formações geológicas Irati e Ponta Grossa, situadas na porção sul da bacia e caracterizadas por seu potencial gerador de hidrocarbonetos. O estudo também inclui a avaliação da viabilidade do abastecimento da usina termoelétrica de Uruguaiana a partir desse recurso, considerando os aspectos geológicos, socioeconômicos e ambientais associados. O projeto visa incentivar o estudo à temática de recursos energéticos não convencionais, com destaque para o shale gas, principal fonte de gás natural não convencional explorada no mundo, além de ressaltar os benefícios na crescente implantação do gás natural na matriz energética brasileira, tanto em aspectos estratégicos quanto econômicos. O projeto propõe a elaboração de um modelo descritivo-comparativo baseado nos aspectos geológicos dos principais campos produtores de shale gas nos Estados Unidos, principal produtor mundial, por meio do qual é avaliado o potencial para ocorrência desse recurso nos folhelhos negros correspondentes às Formações Irati e Ponta Grossa, segundo parâmetros geoquímicos, petrofísicos e geológicos presentes em formações comprovadamente produtoras nos EUA: Marcellus, Barnett e Eagle Ford. O modelo descritivo tem finalidade de avaliar o potencial para exploração, produção e distribuição de gás natural não convencional nas regiões sul e sudeste do Brasil, as quais representam o maior mercado consumidor e demanda por energia no país. Com base na análise comparativa realizada, atribui-se às formações brasileiras potencial moderado a elevado para a geração de shale gas. Entretanto, a viabilidade no abastecimento da usina termoelétrica de Uruguaiana depende, além da geologia local, de fatores político-regulatórios ainda pouco consolidados no país para a incentivar a produção de recursos energéticos não convencionais. / The presented Masters Thesis consists on a geological study of the potential for exploration and production of unconventional natural gas in the Paraná Sedimentary Basin, southern and southeastern Brazil, and northern Uruguay. Therefore, the geological formations Irati and Ponta Grossa, located in the southern portion of the basin, were analyzed in terms of its hydrocarbon generating potential. The study also includes the viability evaluation of this occurrence as a supply for a thermal power plant in Uruguaiana, considering the geological socio-economic and environmental associated aspects. The project aims to promote studies on the topic of unconventional energy resources, especially shale gas, the main unconventional source of natural gas exploited in the world; in addition to emphasizing the advantages in increasing the implement of natural gas into the Brazilian energy matrix, both in strategic and economic aspects. The project proposes the development of a descriptive and comparative model based on geological aspects of the major shale gas producing fields in the United States, the world\'s leading producer; by which we are able to evaluate the potential for occurrence of this resource in the corresponding black shale formations Irati and Ponta Grossa according to geochemical, petrophysical and geological parameters present in these proven producing formations: Marcellus, Barnett and Eagle Ford. The descriptive model was elaborated in order to evaluate the potential for exploration, production and distribution of unconventional natural gas in the southern and southeastern regions of Brazil, which correspond to the largest consumer market and energy demand in the country. Based on a comparative analysis, the Brazilian geological formations are quantified with a moderate to high potential for generating shale gas. However, the viability of using this resource as supply for thermal electricity generation in Uruguaiana depends, in addition to the local geology, to political and regulatory aspects, which are still poorly consolidated among the country, in order to encourage the production of unconventional energy resources.
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Vozes narrativas em A Distant Shore de Caryl Phillips / Narrative voices in A distant shore by Caryl PhillipsMárcia Pedreira 26 September 2008 (has links)
Através do manejo do foco narrativo,dentre outros recursos literários, o Autor alterna e entrelaça narrativas de experiências de personagens oriundas de formações culturais diferentes com a representação do pensamento de cada uma delas sobre o passado, sobre si, sobre o outro e sobre vários espaços em que atuam. Esses espaços se revelam incongruentes com a idéia de um mundo sem fronteiras conforme se apregoa na modernidade tardia. O objetivo desta tese é discutir como aspectos do real histórico e do real psicológico nos tempos em que vivemos se sedimentam na forma deste romance contemporâneo / Through shifts in point-of-view, among other literary resources, the Author alternates and intertwines narratives of the experiences of two characters from contrasting cultural formations with narratives of their thoughts about the past, themselves, each other and the various settings in which they act. These spheres are rendered as incongruent with the idea of a world without borders, so often celebrated in late modernity. The aim of this thesis is to discuss how elements of present-day historical and psychological experience solidify in the form of this particular contemporary novel
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Sensoriamento remoto hiperespectral e definição de espécies indicadoras aplicados à geobotânica no bioma cerrado / Hyperspectral remote sensing and definition of indicator species applied to Geobotany in the Cerrado biome.Cibele Hummel do Amaral 27 February 2015 (has links)
A Geobotânica por sensoriamento remoto é uma técnica de obtenção de informações geológicas indiretas em ambientes cobertos por vegetação e apresenta grandes perspectivas por sua capacidade de otimizar trabalhos de campo e gerar possíveis alvos a serem examinados. O objetivo deste estudo foi realizar a discriminação espectral, em escala de folha e de copa, de espécies arbóreas neotropicais associadas localmente a diferentes formações e fácies geológicas, bem como defini-las remotamente como indicadoras geológicas na Estação Ecológica de Mogi-Guaçu, São Paulo, Brasil. Dados obtidos em 70 unidades amostrais, como texturais de solos e sedimentos, químicos de solos, de nível do freático, altitudinais (modelo digital de terreno),fitossociológicos e fisiológicos/estruturais de vegetação (índices hiperespectrais de vegetação), foram minerados e analisados através da técnica de quantização vetorial Self-Organizing Maps (SOM). Inga veraWilld. subsp. affinis (DC.) T.D. Penn (INVE) e Calophyllum brasiliense Cambess. (CABR) mostraram-se associadas à planície de inundação, incluindo meandros abandonados (Depósitos Aluvionares), com amplo domínio das frações argila e silte nos sedimentos. Qualea grandifloraMart. (QUGR) e Tabebuia ochracea(Cham.) Standl. (TAOC) foram identificadas apenas nas colinas e platôs da Formação Aquidauana,com altas porcentagens das frações areia fina, média e grossa, e escasso silte. Cedrela fissilisVell. (CEFI) e Zeyheria tuberculosa(Vell.) Bur. (ZETU) demonstraram estar associadas a uma fácies aflorante da Formação Aquidauana, com distinta presença das frações de areia grossa e muito grossa, além da baixa porcentagem das frações silte e areiafina. As cinco primeiras espécies tiveram dados bioquímicos e espectrais (400-2.500 nm, FieldSpec 3 Hi-Res) coletados, em escala de folha, tanto no período chuvoso quanto noseco. Seus espectros foram classificados através da técnica Multiple Endmember Spectral Mixture Analysis(MESMA). As espécies foram bem discriminadas em ambos os momentos sazonais, nessa escala de trabalho. Dentre os melhores resultados por intervalo espectral, as exatidões do produtor e do usuário não foram inferiores a 87,5%. Esse sucesso mostrou estar intimamente ligado à alta variabilidade bioquímica observada em suas folhas. As variações intra e interespecíficas em compostos bioquímicos puderam ser correlacionadas às suas variações espectrais. A discriminação espectral em escala de copa foi realizada com dois membros-finais (MF) via MESMA para CEFI, INVE e QUGR. Os pixels das imagenspré-processadas do sistema de sensores aeroportados ProSpecTIR-VS (530-2.532 nm, 1 m de resolução espacial) foram modelados por três MF: MF da classe de espécie-alvo, MF de outras classes de vegetação e sombra fotométrica. A falta de comissão espectrale a relativa baixa omissão espectral atingidas por QUGR na modelagem com dois MF, que incluiu outras classes de vegetação, refletiu em um mapeamento satisfatório de sua fração espectral. As tendências em distribuição dessa espécie indicaram claramente as colinas e platôs da Formação Aquidauana na área estudada. / Geobotany via remote sensing is a technique for obtaining indirect geological information in vegetated areas and presents great perspectives by its capability for field work optimization and target generation to be evaluated afterwards. The aim of this research was to perform the spectral discrimination of Neotropical tree species (at leaf and crown levels) which are locally associated to geological facies and formations in the Mogi-Guaçu Ecological Station, in southeastern Brazil. Data from 70 sampling units, such as soils and sediments texture, soils chemistry, groundwater level, elevation (digital terrain model), plant sociology and vegetation physiology/structure (hyperspectral vegetation indices), were mined and analyzed through the vetorial quantization method called Self-Organizing Maps (SOM; Kohonen, 1982). Inga veraWilld. subsp. affinis(DC.) T.D. Penn (INVE) and Calophyllum brasiliense Cambess. (CABR) demonstrated to be associated to the floodplain, including paleochannels (Alluvial Deposits sequence), with clayey-silty sediments. Qualea grandifloraMart. (QUGR) and Tabebuia ochracea(Cham.) Standl. (TAOC) were sampled on hills and plateaus of the Aquidauna Formation, which stood out for higher fine, medium and coarse sand contents and lower silt content. Cedrela fissilisVell. (CEFI) and Zeyheria tuberculosa(Vell.) Bur. (ZETU) showed be associated to one outcrop facies of the Aquidauna Formation, with distinctive presence of coarse and very coarse sandas well as lower silt and very fine sand contents. Biochemical and spectral (400-2.500 nm, FieldSpec Hi-Res 3) data were collected from the leaves of the first five species, during both rainy and dry seasons. Their spectra were classified through Multiple Endmember Spectral Mixture Analysis(MESMA). All target species were well discriminated at leaf scale. Considering the best classification results per spectral range, user\'s and producer\'s accuracies were always higher than 87,5%. These results seem to be linked to the great biochemical variability of their leaves. The intra and interspecific variability of biochemical compounds were correlated with spectral variability. The spectral discrimination at crown scale was performed with two endmembers (EM) via MESMA for CEFI, INVE e QUGR. The 1-m pixels of the preprocessed ProSpecTIR-VS images (530-2.532 nm) were modeled by three EM: EM of the target species, EM of other vegetation classes, and photometric shade. The QUGRclass achieved a relatively lower spectral omission and had no spectra erroneously assigned to its class in the two EM classification, which included other vegetation classes. This classification result was reproduced in the three EM image unmixing. The distribution tendency of that species clearly indicated the hills and plateaus of the Aquidauana Formation in the study area.
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Infuence of volatiles transport in disks on giant planets composition / L'influence du transport des volatiles dans les disques sur la composition des planètes géantesAli Dib, Mohamad 21 September 2015 (has links)
Ce manuscrit présente des travaux originaux sur la théorie de la formation des planètes.Le but fondamental est de connecter la composition chimique des planètes géantes etdes petits corps avec les processus physiques et chimiques prenant lieu dans le disqueprotoplanétaire.1. Dans le chapitre 1 j'introduis les propriétés fondamentales des disques protoplané-taires ainsi que les bases de la théorie de formation des planètes.2. Dans le chapitre 2 j'attaque le problème du rapport C/O supersolaire mesurérécemment dans WASP 12b. J'élabore un modèle qui suit la distribution et transportde l'eau et du CO gazeux et solides à travers leurs di_usion, condensation,coagulation, gaz drag et sublimation afin de quantifer la variation du rapport C/Odans le disque en fonction du temps et de la distance. Mon modèle montre que,au fur et à mesure du temps, les vapeurs vont être enlever de l'intérieur de leurlignes de glaces respectives, avec le vapeur CO enlevé beaucoup plus lentement quela vapeur d'eau. Cette effet va augmenter le rapport C/O à l'intérieur de la lignede glace de l'eau d'une valeur initiale solaire (0.55) vers une valeur au voisinagede l'unité, permettant de former des planètes géantes avec des rapports C/O _ 1,comme WASP 12b. Je fnis ce chapitre en discutant les preuves observationnellesde cette enlèvement des vapeurs à l'intérieur des lignes de glaces.3. Dans le chapitre 3 j'utilise le même modèle pour interpréter la composition chimiqued'Uranus et Neptune. Je montre comment la formation de ces deux planètessur la sur-densité de glaces prédite par mon modèle sur la ligne de glace de CO peutexpliquer pourquoi ces planètes sont à la fois riches en carbone, pauvres en azote etavec des valeurs D/H sous-cométaires.4. Dans le chapitre 4 je change de sujet vers les propriétés chimiques des météoriteschondritiques, surtout leurs rapports D/H. J'utilise un modèle de disques à 2 couches(actif et morte) avec une code d'évolution D/H pour vérifier si les profiles thermiquesnon monotone trouvés dans ces disques peuvent expliquer la large gamme des valeursD/H trouvé entre les différents familles chondritiques. Je finis ce chapitre en discutantles implications de ce modèle des disques contenant des zones mortes sur laformation de Jupiter.5. Finalement je résume nos résultats dans Conclusions & perspectives, et finis enposant des questions que j'espère voir résolus prochainement. / In this manuscript I present multiple original works on planets formation theory. Themain goal is to connect the chemical composition of giant planets and small bodies to thephysical and chemical processes taking place in the protoplanetary disk.1. In chapter 1 I introduce the fundamental properties of disks and the basics ofplanets formation theory.2. In chapter 2 I tackle the supersolar C/O and subsolar C/H ratios measured recentlyin WASP 12b. I elaborate a model that tracks water and CO vapors and icesevolution through di_usion, condensation, coagulation, gas drag and sublimation inorder to quantify the variation of the C/O ratio as a function of distance and time.My model shows that, over time, vapors will get permanently depleted inside oftheir respective snowlines with CO getting depleted much slower than water. Thiswill increase the C/O ratio inside of the water snowline from the solar value of 0.55to near unity, allowing the formation of giant planets with C/O _ 1, such as WASP12b. I end this chapter by discussing the observational proofs for the existence ofsuch vapor depletions inside the icelines3. In chapter 3 I use the same model to interpret the chemical composition of Uranusand Neptune. I show how the formation of both planets on the CO snowline's icesoverdensity predicted by this model can explain why both planets are rich in carbon,poor in nitrogen and have subcometary D/H ratios.4. In chapter 4 I shift the discussion to the chemical properties of chondritic meteorites,mainly their D/H ratios. I use a snapshot from a layered (active + dead)zones disk model with a D/H ratio evolution code to check if the non monotonicthermal pro_les in these disks can explain the wide range of D/H ratios measuredin the di_erent chondritic families. I end this chapter by discussing the implicationsof the dead zone disk models for the formation of Jupiter.5. I _nally summarize my results in Conclusions & perspectives, and _nish bypointing out several relevant open questions to be hopefully resolved soon.
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Control of Self-Organizing and Geometric FormationsPruner, Elisha January 2014 (has links)
Multi-vehicle systems offer many advantages in engineering applications such as increased efficiency and robustness. However, the disadvantage of multi-vehicle systems is that they require a high level of organization and coordination in order to successfully complete a task. Formation control is a field of engineering that addresses this issue, and provides coordination schemes to successfully implement multi-vehicle systems. Two approaches to group coordination were proposed in this work: geometric and self-organizing formations. A geometric reconfiguring formation was developed using the leader-follower method, and the self-organizing formation was developed using the velocity potential equations from fluid flow theory. Both formation controllers were first tested in simulation in MATLAB, and then implemented on the X80 mobile robot units. Various experiments were conducted to test the formations under difficult obstacle scenarios. The robots successfully navigated through the obstacles as a coordinated as a team using the self-organizing and geometric formation control approaches.
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