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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.
151

Haplotypenbasierte Assoziationsanalyse der COMT-Gen-Region bei schizophrenen Psychosen in einem polydiagnostischen Ansatz / Haplotype based association analysis of the COMT locus further supports a complex genetic interaction with schizophrenic psychoses

Putz, Evelyn January 2008 (has links) (PDF)
In den vergangenen Jahren wurde vermehrt das Gen, welches für Catechol-O-Methyltransferase codiert, als starker Kandidat für ein erhöhtes Schizophrenierisiko diskutiert. Grund dafür ist die zentrale Rolle der Catechol-O-Methyltransferase beim Katecholaminabbau im menschlichen präfrontalen Cortex. Aufgrund der zunehmend akzeptierten Tatsache, daß die singuläre Betrachtung einzelner Marker bei der komplexen genetischen Textur von Kandidatengenen nur wenig zur Erhellung komplexer Erkrankungen beizutragen vermag (Licinio, 2003), untersuchten wir neben dem Val108/158Met-Polymorphismus (rs4680) vier weitere, die COMT-Gen-Region umspannende SNPs (rs2097603, rs740603, rs4818, rs165599) an einer Stichprobe von 459 Schizophrenen und 150 Kontrollpersonen. Zwar ergab sich für den Marker rs740603 auf Intron 1 eine signifikante Allel- (p = 0.0060) und Genotypassoziation (p = 0.019), der funktionelle Val108/158Met-Polymorphismus (rs4680) zeigte aber keinen signifikanten Zusammenhang mit der Erkrankung. Zudem fand sich in unserer Haplotypanalyse keine Markerkombination, die in überdurchschnittlichem Zusammenhang mit schizophrenen Psychosen stand. Für die Untergruppe der zykloiden Psychosen ließ sich bei einem p-Wert von 0.031 eine 4-Marker-Kombination ermitteln, die die SNPs rs740603, rs4818, rs4680 und rs165599 einschliesst und die Region von Intron 1 bis 3´-UTR umspannt. Zusätzlich ergab sich in der Subgruppe der zykloiden Psychosen ein geschlechtsspezifischer Effekt im Sinne eines signifikanten 3-Marker-Haplotypen (rs4818-rs4680-rs165599) (p = .0044) in der Gruppe der Frauen (n = 27) mit rs165599 als stärkstem Einzelmarker. Aufgrund des komplexen genetischen Zusammenhangs zwischen den untersuchten Markern und der Erkrankung sollte auch in der zukünftigen Forschung eine differenzierte Betrachtung der verschiedenen schizophrenen Zustandsbilder angestrebt werden, wie dies die Klassifikation nach Leonhard ermöglicht. Neben gewebsspezifischen Transkriptionsfaktoren könnten auch epigenetische Faktoren, wie die Cytosinmethylierung von CpG-Stellen in promotorregulierenden Regionen, einen Erklärungsansatz für die Entstehung schizophrener Störungsbilder darstellen. / Since several years, the gene encoding catechol-O-methyltransferase (COMT) at chromosome 22q11 is discussed as a strong candidate for schizophrenia susceptibility due to its key function in degredation of catecholamines in the prefrontal cortex, a critical region of the human brain, involved in cognitive control processes, monitoring of information in working memory and in active judgments on information (Petrides, 2005). To test the association of the COMT gene locus with schizophrenia, we analysed five SNPs (rs2097603, rs740603, rs4818, rs4680, rs165599) spanning from the P2 promotor region (MB-COMT) to the 3´-UTR in 459 index cases, which fulfilled diagnistic criteria of schizophrenia according to DSM IV as well as 150 blood donors as population controls. According to differentiated psychopathology (Leonhard, 1999) probands were categorized into cycloid psychosis, unsystematic schizophrenia and systematic schizophrenia prior to genotyping. In intron 1 the marker rs740603 showed significant allele (p = 0.0060) and genotype (p = 0.019) association, but the functional Val105/158Met variant (rs4680) failed significant association with disease. Considering COMT haplotypes none of the marker combinations showed evidence for an association with schizophrenia. In the subgroup of cycloid psychosis we found 4-locus marker combinations rs740603-rs4818-rs4680-rs165599 associated with disease at p-level 0.031, spanning a region from intron 1 to the 3´-UTR. In conclusion, the genetic interaction of COMT SNPs and haplotypes and schizophrenia susceptibility appears complex across different populations and psychopathological phenotypes. Particularly structures potentially involved in mRNA expression levels need further scrutiny.
152

Os diários de juventude de Liev Tolstói, tradução e questões sobre o gênero de diário / The youth diaries of Leo Tolstoy, translation and studies on the diary genre

Erasso, Natalia Cristina Quintero 24 March 2011 (has links)
Liev Tolstói, autor russo do século XIX, reconhecido tanto pelos acadêmicos como pelo público geral como um dos maiores romancistas da história, ao longo de mais de sessenta anos escreveu um diário paralelamente a sua vasta obra artística. No conjunto de toda a produção escrita do autor, o diário constitui a sua obra mais volumosa, contudo, quase inexplorada em língua portuguesa. O presente trabalho propõe-se aproximar o leitor brasileiro dessa faceta menos conhecida de Tolstói por meio da tradução, direta do russo, dos primeiros sete anos do diário (1847 1854). Observa-se o que há de particular nesse texto de Tolstói, no âmbito do diário como gênero literário e, por fim, questiona-se a possibilidade de ler o diário de Tolstói como criação artística independente ou se deve ele ser tratado como um coadjuvante na interpretação das obras literárias do autor. / Leo Tolstoy, great Russian writer of the nineteenth century, recognized as one of the leading novelists in the history of the genre, both by scholars and the general public, spent over sixty years writing a diary. Throughout the vast production written by the author, this diary is his most voluminous work, yet still unexplored and almost unknown in Portuguese. This work presents a translation directly from Russian of the first seven years of the diary (1847 - 1854) and also makes a first reflection on the nature of the text which encompasses the characteristics of Tolstoy\'s diary related to the genre. Then it analyzes whether Tolstoys diary can be treated as an artistic creation or as supporting text in the interpretation of literary works of the author.
153

Reservat?rios estrat?gicos de CO2 para futuro uso em projetos de recupera??o avan?ada de petr?leo e armazenamento geol?gico de CO2 no Brasil

Martins, Jo?o Miguel Faim 22 June 2009 (has links)
Made available in DSpace on 2015-04-14T13:58:31Z (GMT). No. of bitstreams: 1 413811.pdf: 2013126 bytes, checksum: b51679af9a90b4c288c6f2a5c7658589 (MD5) Previous issue date: 2009-06-22 / A seguran?a energ?tica do pa?s e o cont?nuo aumento da demanda de hidrocarbonetos no mundo t?m exigido uma r?pida resposta por parte das ind?strias petrol?feras de forma a que n?o haja interrup??es em seu fornecimento. A utiliza??o do CO2 como subst?ncia capaz de aumentar a recupera??o de hidrocarbonetos em campos de petr?leo ? uma atividade conhecida e de efici?ncia comprovada. Apesar da tecnologia de separa??o e captura de CO2 ser ainda relativamente cara, ? de fundamental import?ncia que as companhias petrol?feras comecem a ter reservas estrat?gicas deste g?s para que tenham capacidade de suprir aumentos de demandas de hidrocarbonetos. Desta forma ser? poss?vel maximizar o tempo de vida ?til dos campos de ?leo, tornando-os mais sustent?veis em termos ambientais e econ?micos. Assim, o presente estudo introduz o conceito in?dito de captura e armazenamento geol?gico din?mico de CO2 - DCCS, que tem como objetivo principal, formar reservat?rios estrat?gicos de CO2, atrav?s da captura do CO2 de fontes emissoras, transporte e respectiva inje??o em reservat?rio, que podem ser r?pida e facilmente utilizados como fonte de CO2 para recupera??o avan?ada de ?leo - EOR em campos maduros de petr?leo. O DCCS tem a fun??o de garantir que n?o ocorram falhas no abastecimento de CO2 em projetos de EOR, n?o comprometendo a viabilidade econ?mica destes. O desenvolvimento de uma metodologia de sele??o de regi?es com potencial para implanta??o de projetos de DCCS ? tamb?m foco deste trabalho. A aplicabilidade do DCCS nos estados brasileiros ? avaliada na disserta??o, segundo esses mecanismos.
154

Desenvolvimento e avalia??o do potencial antioxidante de uma nanoemuls?o de uso t?pico

Selbach, Sarah Ledur 29 February 2016 (has links)
Submitted by PPG Biotecnologia Farmac?utica (mpbf@pucrs.br) on 2017-08-01T13:00:08Z No. of bitstreams: 1 SARAH_LEDUR_SELBACH_DIS.pdf: 2769655 bytes, checksum: 75da9b372aa505302e3bba0e64bdc393 (MD5) / Rejected by Caroline Xavier (caroline.xavier@pucrs.br), reason: Devolvido devido a diverg?ncia entre o t?tulo de capa e o t?tulo da folha de rosto. Confirmar qual o correto. on 2017-08-04T13:28:42Z (GMT) / Submitted by PPG Biotecnologia Farmac?utica (mpbf@pucrs.br) on 2017-08-08T13:07:34Z No. of bitstreams: 1 SARAH_LEDUR_SELBACH_DIS.pdf: 2769655 bytes, checksum: 75da9b372aa505302e3bba0e64bdc393 (MD5) / Approved for entry into archive by Caroline Xavier (caroline.xavier@pucrs.br) on 2017-08-10T18:18:37Z (GMT) No. of bitstreams: 1 SARAH_LEDUR_SELBACH_DIS.pdf: 2769655 bytes, checksum: 75da9b372aa505302e3bba0e64bdc393 (MD5) / Made available in DSpace on 2017-08-10T18:24:39Z (GMT). No. of bitstreams: 1 SARAH_LEDUR_SELBACH_DIS.pdf: 2769655 bytes, checksum: 75da9b372aa505302e3bba0e64bdc393 (MD5) Previous issue date: 2016-02-29 / According to INCA (National Institute of Cancer) the cases of skin cancer are increasing exponentially, and it is the world's largest incidence. The increase in ultraviolet index, due to the depletion of the ozone layer, and excessive sun exposure contribute to this fact. The formation of reactive oxygen species (ROS) can be from endogenous and exogenous factors, mainly by exposure to ultraviolet (UV). This are directly linked to the development of several types of cancer, especially skin cancer and photoaging. ROS or free radicals alter the DNA and other biomolecules of the skin, causing genetic mutations that promote and induce cancer incidence. Consequently, the search for new antioxidant substances for topical use is of utmost importance for the prevention of photodamage and skin cancer. This project of master dregree aims to develop a topical nanoemulsion containing these active substances Green tea (Camellia sinensis) and Buriti Oil (Mauritia flexuosa), which have antioxidant properties, and to study their stability in vitro and assess its properties. As a result it is expected to develop a cosmetic raw material that meets a demand of the consumer market, contributing to the prevention of skin cancer and to decrease the signs of cutaneous photoaging. / Segundo o INCA (Instituto Nacional de C?ncer), o c?ncer de pele possui a maior incid?ncia mundial e seus casos v?m aumentando exponencialmente. O aumento do ?ndice ultravioleta devido ? diminui??o da camada de oz?nio e a exposi??o solar excessiva contribuem para este fato. A forma??o de esp?cies reativas de oxig?nio (EROs), se d? por fatores end?genos e ex?genos, principalmente pela exposi??o aos raios ultravioleta (UV). Esta est? diretamente ligada ao desenvolvimento de diversos tipos de c?ncer, especialmente o de pele. As EROs, ou radicais livres, alteram o DNA e demais biomol?culas da pele, ocasionando muta??es gen?ticas que favorecem e induzem a incid?ncia de c?ncer, e causam fotoenvelhecimento. Consequentemente, a busca de novos ativos com propriedades antioxidantes de uso t?pico ? de extrema import?ncia para a preven??o de fotodanos e c?ncer de pele. Este projeto de mestrado teve como objetivo desenvolver uma nanoemuls?o t?pica contendo estas subst?ncias ativas, Ch? Verde (Camellia sinensis) e ?leo de Buriti (Mauritia flexuosa), que apresentam propriedades antioxidantes, estudar sua estabilidade e avaliar in vitro suas propriedades. Como resultado, espera-se obter um insumo cosm?tico que atenda uma demanda do mercado de consumidores, contribuindo para preven??o do c?ncer de pele e para diminui??o dos sinais do fotoenvelhecimento cut?neo.
155

Obten??o de rutina ricinoleato atrav?s da rea??o de esterifica??o com ?leo de mamona

Ribeiro, Fernanda Pinheiro de Carvalho 03 August 2016 (has links)
Submitted by Ricardo Cedraz Duque Moliterno (ricardo.moliterno@uefs.br) on 2017-07-12T22:04:17Z No. of bitstreams: 1 Tese vers?o final com ficha.pdf: 2919026 bytes, checksum: e0cf3c8db3a8cc81cb105cb2fbb154b3 (MD5) / Made available in DSpace on 2017-07-12T22:04:17Z (GMT). No. of bitstreams: 1 Tese vers?o final com ficha.pdf: 2919026 bytes, checksum: e0cf3c8db3a8cc81cb105cb2fbb154b3 (MD5) Previous issue date: 2016-08-03 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The flavonoid rutin (3-0-rutinos?deo-quercetin) stands out among the natural products as a promising alternative in the fight against degenerative diseases and related to aging. However, the low solubility and stability thereof in different media, especially lipophilic limited applications in pharmaceutical preparations. The biocatalytic transformation by enzymatic acylation has been suggested by several authors, with good reaction yields. In this sense, the objective of this study was to promote the enzymatic acylation of rutin, using castor oil as acylating agent and lipase as a catalyst, to characterize the formed product, estimate the efficiency of bioconversion, and to investigate in vitro the antioxidant activity and cytotoxic effect opposite the reaction product Vero cells. The catalytic transformation occurred at 50?C for 120 hours. The product was subjected to column chromatography, followed by filtration by Sephadex LH-20. The chemical structure of rutin-O-ricinoleate was determined by Nuclear Magnetic Resonance (NMR) 1H and 13C and by liquid chromatography / mass spectroscopy (HPLC/MS). In another experiment, it was observed the formation of the ester content by High Performance Liquid Chromatography coupled to a detector diode arrangements (HPLC-DAD) under conditions which allow assessing the reaction yield over 120 hours. The analytical method proposed has been validated considering the linearity parameters, accuracy, precision, limit of quantification and detection proved to be suitable for quantification of ricinoleato rutin. It was found by this method that the reaction product maintained the antioxidant capacity of rutin and there was no evidence of cytotoxicity. / O flavonoide rutina (quercetina-3-0-rutinos?deo) se destaca entre os produtos naturais como uma alternativa promissora no combate ?s doen?as degenerativas e relacionadas ao envelhecimento. No entanto, a baixa solubilidade e estabilidade da mesma em diferentes meios, especialmente lipof?licos, limitam as aplica??es em prepara??es farmac?uticas. A transforma??o biocatal?tica, atrav?s da acila??o enzim?tica, tem sido sugerida por diversos autores, com bons rendimentos reacionais. Neste sentido, o objetivo do presente trabalho foi promover a acila??o enzim?tica da rutina, utilizando ?leo de mamona como agente acilante e lipase como catalizador, caracterizar o produto formado, estimar o rendimento da bioconvers?o, al?m de investigar in vitro a atividade antioxidante e o efeito citot?xico do produto reacional frente ?s c?lulas Vero. A transforma??o catal?tica ocorreu em temperatura de 50?C, durante 120 horas. O produto foi submetido ? cromatografia em coluna, seguida de filtra??o por Sephadex LH-20. A estrutura qu?mica da rutina-O-ricinoleato, foi determinada por Resson?ncia Magn?tica Nuclear (RMN) 1H e de 13C e por cromatografia l?quida/espectroscopia de massas (CLAE/EM). Em outro experimento, foi verificado o teor de forma??o do ?ster por Cromatografia ? L?quidos de Alta Efici?ncia acoplado a um detector de arranjos Diodos (CLAE-DAD), em condi??es que permitiram avaliar o rendimento reacional ao longo de 120 horas. O m?todo anal?tico proposto foi validado considerando os par?metros de linearidade, exatid?o, precis?o, Limites de quantifica??o e de detec??o mostrando-se adequado para a quantifica??o da rutina ricinoleato. Verificou-se pelos m?todos avaliados, que o produto reacional manteve a capacidade antioxidante da rutina e que n?o houve evid?ncia de citotoxicidade.
156

Electric Propulsion and Controller Design for Drag-Free Spacecraft Operation in Low Earth Orbit

Marchetti, Paul J 20 December 2006 (has links)
"A study is presented detailing the simulation of a drag-free follow-on mission to NASA’s Gravity Recovery and Climate Experiment (GRACE). This work evaluates controller performance, as well as thrust, power, and propellant mass requirements for drag-free spacecraft operation at orbital altitudes of 160 - 225 kilometers. In addition, sensitivities to thermospheric wind, GPS signal accuracy and availability of ephemeris data are studied. Orbital dynamics were modeled in Matlab and take into account 2 body gravity effects, J2-J6 non-spherical Earth effects, atmospheric drag and control thrust. A drag model is used in which the drag acceleration is a function of the spacecraft’s relative velocity to the atmosphere, and a “drag parameter,” which includes the spacecraft’s drag coefficient and local mass density of the atmosphere. A MSISE-90 atmospheric model is used to provide local mass densities as well as free stream flow conditions for a Direct Simulation Monte Carlo drag analysis used to validate the spacecraft drag coefficient. The controller is designed around an onboard inertial sensor which uses a freely floating reference mass to measure deviations in the spacecraft position, resulting from non-gravitational forces, from a desired target orbit. Thruster (control actuator) models are based on two different Hall thrusters for providing the orbital along-track acceleration, colloid thrusters for the normal acceleration, and a miniature xenon ion thruster (MiXI) for the cross-track acceleration. The most demanding propulsion requirements correspond to the lowest altitude considered, 160 kilometers. At this altitude the maximum along-track thrust component is calculated to be 98 millinewtons with a required dynamic (throttling) response of 41 mN/s. The maximum position error at this altitude was shown to be in the along-track direction with a magnitude of 3314.9 nanometers and a peak spectral content of 1800 nm/sqrt(Hz) at about 0.1 Hz. At 225 kilometers, the maximum along-track thrust component reduces to 10.3 millinewtons. The maximum dynamic response at this altitude is 4.23 mN/s. The maximum along-track position error is reduced to 367.9 nanometers with a spectral content peak of 40 nm/sqrt(Hz) at 0.1 Hz. For all altitudes, the maximum state errors increase as the mission length increases, however, higher altitude missions show less of a maximum displacement error increase over time than those of lower orbits. The ability of a colloid thruster to control the normal drift is found to be dependent on how frequently the spacecraft state data is updated. Reducing the period between updates from 10 seconds to 1 second reduces the maximum normal state error component from 199 nanometers to less than 32 nanometers, suggesting that spacecraft state update frequency could be a major driver in keeping the spacecraft on the target trajectory. Sensitivity of maximum required thrust and accumulated sensor error to measurement uncertainty is found to be less of a driver than state update frequency. A ‘worst case” thermospheric wind gust was modeled to show the increase on propulsion requirements if such an event were to occur. At 200 kilometers, maximum winds have been measured to be in increase of 650 m/s in the westward direction in the southern pole region. Assuming the majority of the 650 m/s gust occurs over a 4 second time span, the maximum required cross-track thrust at 200 kilometers increases from 1.12 to 2.01 millinewtons. This large increase may drive the thruster choice for a drag-free mission at a similar altitude. For the spacecraft point design considered with a propellant mass fraction of 0.18, the mission lifetime for the 160 km case was calculated to be 0.76 years. This increases 2.27 years at an altitude of 225 km."
157

Efeito da lubrifica??o sobre a pr?-carga e o torque de remo??o de parafusos odontol?gicos de conex?o submetidos a ciclos de aperto e desaperto

Kunz, Tiago 30 November 2015 (has links)
Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2016-02-11T10:24:45Z No. of bitstreams: 1 DIS_TIAGO_KUNZ_COMPLETO.pdf: 2813092 bytes, checksum: 4a31e9fa6f6b00754e7f702733f5c592 (MD5) / Made available in DSpace on 2016-02-11T10:24:45Z (GMT). No. of bitstreams: 1 DIS_TIAGO_KUNZ_COMPLETO.pdf: 2813092 bytes, checksum: 4a31e9fa6f6b00754e7f702733f5c592 (MD5) Previous issue date: 2015-11-30 / Screw loosening is often a complication reported in prosthetic implants. The torque develops a compressive clamping force between parts called preload, which holds the components together and the reducing of friction between the surfaces has been shown to increase its value. Dry lubricants, also called coatings have been used and the results are satisfactory, but the use of liquid lubricants is still little explored, which is the aim of this study. For this, 14 titanium screws and 14 screws with (Diamond-Like Carbon) DLC coating were randomly assigned to four groups (Titanium; DLC, Titanium with oil, and DLC with oil) and subjected to five cycles of tightening and loosening. The screws of groups Titanium with oil and DLC with oil were lubricated with castor oil. The preload was measured by a preload gauge cell, especially developed for the study. The results of preloads and average removal torques for torques of 20 and 32Ncm at 2 different times were analyzed: after the first grip and after five consecutive grips. At the end of the analysis, the thread pitches were measured to rule out plastic deformation. The Group DLC had higher pre-load values at all time points, but it was only significant after the sequence grips with 32 Ncm, and in the absence of oil. It was concluded, therefore, that the castor oil lubrication was not able to significantly increase the preload values or removal torque. / O afrouxamento do parafuso ? uma complica??o frequentemente reportada em pr?teses sobre implantes. O torque desenvolve uma for?a compressiva de aperto entre as partes chamada pr?-carga, que mant?m os componentes unidos, e a redu??o do atrito entre as superf?cies tem demonstrado aumentar o seu valor. Lubrificantes secos, tamb?m chamados de recobrimentos, t?m sido utilizados e os resultados s?o satisfat?rios, contudo o emprego de lubrificantes l?quidos ainda ? pouco explorado, sendo o objetivo deste estudo. Para isso, 14 parafusos de tit?nio e 14 parafusos com recobrimento de Diamond-Like Carbon (DLC) foram aleatoriamente alocados em quatro grupos (Tit?nio; DLC; Tit?nio com ?leo; e DLC com ?leo) e submetidos a cinco ciclos de aperto e desaperto. Os parafusos dos grupos Tit?nio com ?leo e DLC com ?leo foram lubrificados com ?leo de mamona. A pr?-carga foi mensurada por meio de uma c?lula aferidora de pr?-carga, desenvolvida especialmente para o estudo. Foram analisados os resultados das pr?-cargas e torques de remo??o m?dios para os torques de 20 e 32 Ncm em dois momentos distintos: ap?s o primeiro aperto e depois de cinco apertos consecutivos. Ao fim das an?lises, os passos de roscas foram mensurados para descartar deforma??es pl?sticas. O Grupo DLC apresentou maiores valores de pr?-carga em todos os momentos de avalia??o, contudo ele s? foi significativo ap?s a sequ?ncia de apertos com 32 Ncm, e na aus?ncia do ?leo. Concluiu-se, portanto, que a lubrifica??o com ?leo de mamona n?o foi capaz de aumentar significativamente os valores da pr?-carga ou do torque de remo??o.
158

A import??ncia do direito do petr??leo para administra????o p??blica sob a ??tica do novo marco regulat??rio: uma estatal para o pr??-sal

Guimar??es Neto, Napole??o Lopes 03 August 2016 (has links)
Submitted by Sara Ribeiro (sara.ribeiro@ucb.br) on 2017-09-05T14:13:33Z No. of bitstreams: 1 NapoleaoLopesGuimaraesNetoDissertacao2016.pdf: 1210361 bytes, checksum: d6e06a5e4cfc5b49319537435d7216b4 (MD5) / Approved for entry into archive by Sara Ribeiro (sara.ribeiro@ucb.br) on 2017-09-05T14:15:26Z (GMT) No. of bitstreams: 1 NapoleaoLopesGuimaraesNetoDissertacao2016.pdf: 1210361 bytes, checksum: d6e06a5e4cfc5b49319537435d7216b4 (MD5) / Made available in DSpace on 2017-09-05T14:15:26Z (GMT). No. of bitstreams: 1 NapoleaoLopesGuimaraesNetoDissertacao2016.pdf: 1210361 bytes, checksum: d6e06a5e4cfc5b49319537435d7216b4 (MD5) Previous issue date: 2016-08-03 / This is the context of the importance of establishing a new regulatory framework for the exploration and production of oil and natural gas reserves in the area of pre-salt layer, through constitutional confrontation of various doctrinal and jurisprudential understandings. In this sense, the central legal aspect of this work consists in the performance of the monopoly activities assured the Union considering the need to establish a new state company for that specific purpose. / Trata-se da contextualiza????o da import??ncia da institui????o de um novo modelo regulat??rio para a explora????o e produ????o das reservas de petr??leo e g??s natural na ??rea da camada do pr??-sal, mediante confronto constitucional de diversos entendimentos doutrin??rios e jurisprudenciais. Nesse sentido, o aspecto jur??dico central dessa disserta????o consiste no exerc??cio das atividades integrantes do monop??lio assegurado ?? Uni??o considerando a necessidade de constitui????o de uma nova empresa estatal para essa finalidade espec??fica.
159

Tolstoi et Martin Du Gard (Guerre et paix et Les Thibault)

Stefanson, Blandine Marie January 1971 (has links)
xviii, 419 leaves / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.1972)--University of Adelaide, Dept. of French Language and Literature, 1972
160

Adaptive Antenna Arrays for Satellite Mobile Communication Systems

Beyene, Dereje, Degefa, Befkadu January 2010 (has links)
<p>Adaptive antenna arrays have a great importance in reduction of the effect of interference and increase the capacity for the mobile satellite communication. Interference and multipath fading remain a main problem for reception of signals. These two problems obviously affect the overall capacity.  Adaptive antenna arrays in the handheld mobile apparatus will be the solution for the above two problems.</p><p> </p><p>Satellite mobile communication is one of the growing fields in the communication area where terrestrial infrastructures are unable or ineffective to supply. Maritime, aeronautical and land mobile are some of the applications. During natural disasters where ground services are stopped, mobile satellite communications has great importance. Following the hurricane season, the Asian Tsunami and the devastating Haiti earthquake, mobile satellite communications had played a great role to fill the communication gaps.  The satellites can be tracked automatically by adaptive antenna array when it moves in its orbital plane.</p><p> </p><p>In this thesis the methods that how the adaptive antenna array combats interferers is presented and simulated using MATLAB software. The performance of the adaptive antenna array is evaluated by simulating the directivity pattern of the antenna and Mean Square Error (MSE) graph for different scenario like Signal to Interference Noise ratio (SINR), number of iterations, antenna array elements and convergence factor (μ), assuming the signals are coming from different Direction of Arrival (DOA).</p><p> </p><p> </p>

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