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Cooper, Sharon Rose. "δ-Protocadherin Function: From Molecular Adhesion Properties to Brain Circuitry." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1492457066344753.
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Roux, Milena. "Identification and characterization of EFR-interacting proteins." Thesis, University of East Anglia, 2010. https://ueaeprints.uea.ac.uk/26674/.
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Nef, Annliese. "L'élément islamique dans la Sicile normande : identités culturelles et construction d'une nouvelle royauté (XIe - XIIe siècles)." Paris 10, 2001. http://books.openedition.org/efr/5336.
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En 1061, lorsque les Normands entreprennent la conquête de la Sicile, la population insulaire est majoritairement arabo-musulmane, même si la partie orientale demeure profondément hellénisée. Malgré ces difficultés, l'île s'offre comme un terrain de choix pour l'affirmation de la dynastie des Hauteville et la construction d'un pouvoir sans partage. Minoritaires tant d'un point de vue démographique que culturel, ces hommes du nord ont à faire face à un véritable défi. En quelques générations, le comte Roger et ses descendants réussissent à instaurer une royauté qui, pour durer, doit faire l'objet d'un consensus en Sicile même et jouir d'une reconnaissance à l'extérieur. Cette quête de légitimité, qui passe par la mobilisation des héritages latin, islamique et grec (byzantin) qui sont aussi bien ceux des conquérants que des conquis, fait de la Sicile un véritable laboratoire où sont mises à l'épreuve de nouvelles conceptions liées à la royauté. Ce problème politique se pose essentiellement en termes culturels. Comment dire, par exemple, le pouvoir politique dans un contexte trilingue ? Les Normands adoptent ici une position paradoxale. Utilisant le grec, le latin et l'arabe dans l'administration, ils se servent de ces idiomes autant pour reprendre à leur compte les deux traditions insulaires que pour tenir à distance leurs sujets. La référence religieuse n'est pas moins délicate à manier à une époque où la dimension religieuse est étroitement liée à la légitimation du pouvoir royal à Byzance, en Occident et dans les pays islamiques. De la fondation d'évêchés latins à la fin du XIe siècle, on passe à la promotion d'un milieu melkite (chrétien hellénophone et arabophone de Syrie) et mozarabe, puis à l'exaltation d'un monothéisme souple. L'échec de cette tentative unique qui associe trois traditions culturelles découle de l'écart qui se crée peu à peu entre des souverains dont l'identité culturelle mêle des éléments de plus en plus divers et des groupes culturels qui, entre effacement et résistance, ne se retrouvent guère dans cette convergence partielle et limitée au milieu de courIn 1061, when the Normans begin their conquest of Sicily, the insular population is for the main part of Islamic culture, even if the Oriental regions remain hellenized in depth. In spite of these difficulties, the island offers a perfect ground for the affirmation of the Hautevilles' dynasty and for the construction of an unshared power. Nonetheless, a representing a cultural minority Sicily, these men from the North face a real challenge. Within a few generations, Count Roger and his descent will set up a kingship which, in order to last, must be supported by a consensus in the island and be acknowledged legitimacy outside of it. Such a quest for legitimacy requires the mobilization of Latin, Islamic and Greek (Byzantine) legacies which belong to the conquerors and to the insular population. It transforms Sicily in a true laboratory where new conceptions linked to Kingship are tested. This political problem presents itself essentially in cultural terms. How can, for example, political power be expressed in a trilingual context ? The Norman adopt on this issue a paradoxical position. They use Greek, Latin and Arabic in their administration as much in order to resume with the insular traditions as in order to put distance between themselves and their subjects. Handling the religious reference is no less difficult at a time when the religious dimension is linked straightly to the legitimation of royal power, at Constantinople, as well as in Occident and in the Islamic countries. From the foundation of Latin bishoprics, they go on with the promotion of a Melkite (Christian Hellenophone and Arabophone from Syria) and Mozarabic milieu, ending up with the exaltation of a flexible monotheism. The failure of this unique attempt which associates three cultural traditions is due to the gap that appears little by little between kings whose cultural identity put together more and more diverse elements and cultural groups which, oscillating between disappearance and resistance, do not perceive much of themselves in this partial convergence, limited to the royal Court
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Fenet, Annick. "Caractères et cultes marins des divinités olympiennes dans le monde grec d'Homère à la fin de l'époque hellénistique : contribution à l'étude de la religion des marins grecs." Paris 10, 1998. http://books.openedition.org/efr/5550.
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L'approche religieuse de la mer par les grecs est communément assimilée aux seules figures de Poséidon et des divinités dites + marines, telles les néréides, ino ou les Dioscures. Or, dans la pratique, il s'avère que la majorité des cultes réalisés dans un contexte maritime ou lors d'un voyage en mer s'adressent aux divinités olympiennes ou douze dieux. L'ensemble du travail tend à définir les pratiques religieuses des marins grecs et à considérer la place primordiale qu'y occupent les dieux olympiens. Dans une premiere partie, sont ainsi passées en revue les relations de chacun de ces dieux avec la mer : à travers les récits mythologiques et épiques, puis géographiquement à travers tout le monde grec, région par région, sanctuaire par sanctuaire. Dans une seconde partie, sont décrites les pratiques religieuses spécifiques au monde maritime. En mer, la présence des dieux se manifeste à bord du bateau de differentes manières : par l'ornementation navale, par les noms théophores du navire, par les ancres portant inscriptions ou décors. A terre, en relation avec un voyage maritime, sont consacrés dans des sanctuaires des bateaux sous differentes formes, ainsi que des ancres et des ex-voto de pêche. L'étendue de la période étudiée permet de discerner des évolutions dans les caractères prêtés aux dieux et dans les cultes maritimes, et l'importance de ceux-ci à l'époque archaïque. Leur répartition et la topographie des sanctuaires présentent des cohérences liées aux méthodes et conditions de navigation antique. Le culte marin des divinités olympiennes manifeste de la grande souplesse de la religion grecque - adaptation de personnalités divines a un contexte géographique ou social - tout en formant un ensemble ordonneThe religious approach of the sea by Greeks is commonly classed as the figure of Poseidon and deities so said + marine; like nereids, ino or Dioscuri. But, in the reality it turns out that the majority of worships make in maritime context or in travel by sea address to the Olympian deities or twelve gods. All this study aims to define the religious practices of Greek sailors and to consider the primordial place of the Olympian deities. In the first part, are reviewed relationships of all these gods with the sea : by the mythological and epic words, then geographically through all Greek world, region by region, sanctuary by sanctuary. In the second part, are described the religious practices specific to maritime world. By sea, the presence of gods emerge aboard ships by different ways : by nautical ornamentation, by theophoric names, by anchors with inscriptions or decorations by land, in connection with nautical travel, are dedicated in sanctuaries boats in different forms, anchors and fishing gifts. The duration of period examined permit to discern evolutions in the features of gods and in the maritime worships, and importance of these in the archaic time. There repartition and the topography of sanctuaries present coherences connected to methods and conditions of ancient seamanship. The worship of Olympian deities demonstrate a large adaptability of Greek religion - adaptation of sacred personalities in a geographical or social context - making an arranged whole
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Dalmases, Massegú Alba 1982. "Acquired resistance to the anti-EFGR monoclonal antibody cetuximab in colorectal cancer." Doctoral thesis, Universitat Pompeu Fabra, 2012. http://hdl.handle.net/10803/84183.
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EGFR is a transmembrane tyrosine kinase receptor from the HER family which, upon ligand stimulation, activates different signaling pathways involved in tumorogenesis. EGFR can be targeted by monoclonal antibodies, as cetuximab and panitumumab, which bind to EGFR preventing ligand stimulation of the receptor.
Cetuximab and panitumumab are approved for colorectal cancer treatment. However, its clinical success is uniformily limited by the development of acquired drug resistance.
We describe a new mechanism of acquired resistance to cetuximab in colorectal cancer that was due to a missense mutation in the EGFR ectodomain (S492R mutation). Upon chronic exposure to cetuximab, colorectal cancer cell lines acquired S492R mutation and became resistant to the treatment. We observed that cetuximab was not able to bind mutant EGFR. Notably, this amino acid change did not affect the ability of panitumumab to bind to EGFR, and panitumumab effectively suppressed growth of mutant cells. EGFRS492R mutation was detected in 2 out of 10 tumor specimens from patients following progression on cetuximab. One of these patients was subsequently treated with single agent panitumumab yielding a partial response. The S492R mutation defines a novel biomarker of resistance to cetuximab but not to panitumumab in colorectal cancerEGFR és un receptor transmembrana tirosina cinasa de la família HER el qual, després de l’estimulació mitjançant lligands, activa vies de senyalització involucrades en processos tumorogènics. L’EGFR es pot inhibir amb anticossos monoclonals, com cetuximab i panitumumab, que s’uneixen al receptor prevenint-ne l’activació per part dels lligands. Cetuximab i panitumumab estan aprovats per al tractament del càncer colorectal, però el seu ús es veu limitat per el desenvolupament de resistència adquirida al tractament. Nosaltres describim un mecanisme de resistència adquirida a cetuximab en càncer colorectal degut a l’adquisió d’una mutació en el domini extracel•lular de l’EGFR, la mutació S492R. Durant l’exposició crònica a cetuximab, linies cel•lulars de càncer colorectal van adquirir la mutació S492R tornat-se resistents al tractament. Cetuximab no era capaç d’unir-se a l’EGFR mutat. Aquests canvi d’aminoàcid no afectava a l’habilitat que té panitumumab a unir-se al EGFR, pertant, panitumumab suprimia el creixement de les cèl•lules tumorals mutades. Vam detectar la mutació EGFRS492R en 2 de 10 mostres tumorals de pacients que havien recaigut al tractament amb cetuximab. Un d’aquest pacients va ser posteriorment tractat amb panitumumab obtenint-ne una resposta tumoral parcial. La mutació S492R defineix un nou mecanisme de resistència a cetuximab però no a panitumumab en el tractament del càncer colorectal.
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Dickinson, John C. "AFM, CAFM, and EFM Studies of the GaN System." VCU Scholars Compass, 2003. http://scholarscompass.vcu.edu/etd/4522.
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This thesis discusses a variety of techniques based on the atomic force microscope (AFM), and their application to the GaN materials system. In particular, the local conductivity and contact potential of surfaces have been measured using the techniques of Conductive AFM (CAFM) and Surface Potential Electric Force Microscopy (SPEFM), respectively. CAFM studies of GaN surfaces have revealed that prismatic planes around islands and pits on surfaces can lead to enhanced conductivity, which may be related to leakage problems in device applications. With regard to SP-EFM work, the change in surface potential associated with inversion domains on Ga-polar GaN has been imaged, yielding voltage differences up to 90 mV. Given that such inversion domains increase carrier scattering and can degrade device performance, their identification using this technique is important. SP-EFM has also been used to map the local surface potential in the active region of Modulation Doped Field Effect Transistors (MODFET's). This is the first step in a proposed study to investigate the effects of current lag in such devices.
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Fantini, Irene Heleonora Seda Pinto. "Otimização dos codificadores VSELP e EFR por refinamento na modelagem autoregressiva." [s.n.], 2000. http://repositorio.unicamp.br/jspui/handle/REPOSIP/260154.
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Orientador : Luis Geraldo Pedroso MeloniDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação
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Mestrado
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Saborit, Rojas Enrique. "Update of a Externally Fired Micro Turbine (EFMT) for residential micro combined Heat and Power." Thesis, KTH, Kraft- och värmeteknologi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-118754.
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Chen, Amber Marie. "Developing and Studying the Effectiveness of EFR Annotations for Chinese Language Learners." BYU ScholarsArchive, 2009. https://scholarsarchive.byu.edu/etd/2299.
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This project is intended to take the film To Live, directed by Zhang Yimou, and apply the Electronic Film Review (EFR) approach to it in a Chinese as a Foreign Language (CFL) setting. The Electronic Film Review project, developed by Alan K. Melby, is aimed at providing a superior language learning experience for Americans learning Chinese. Using feature films as a teaching tool has been found to stimulate and motivate students to achieve higher language levels, but in order for optimal learning to occur the material must be challenging yet accessible to the student. Most feature films, by themselves, are too advanced for the average language learner. The EFR approach provides annotations designed specifically for the feature film with the language learner in mind. These annotations can include access to vocabulary helps, grammar and cultural notes in order to bridge the gap between the learner and the film. It does not alter the film itself. This approach has been used with ESL students (English annotations), French language learners, and with Korean ESL learners (Korean annotations), but has not been developed for students learning Chinese. The purpose of this project is not only to apply the technology of the Electronic Film Review program to a Chinese film for the purpose of aiding Chinese language learners, but also to critique whether or not the tool is effective in helping students to gain better listening comprehensions skills and therefore ultimately better language skills. Previous studies have not shown clear results on this issue. This thesis will briefly review what the EFR project is and how it has been used with other films and languages as well as the findings up to this point. Then it will look at the effects of annotations on several aspects of listening comprehension as well as student preferences and reactions. It will then evaluate the results collectively to determine whether students watching the film without the help of EFR annotations show differing levels of listening comprehension achievement when compared with those using the EFR tools. Suggestions will be made for further improvements.
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Sun, Yu. "Lating Future Land Use Change in the East Fork Little Miami River (EFLMR) Watershed in Ohio." Cincinnati, Ohio : University of Cincinnati, 2009. http://www.ohiolink.edu/etd/view.cgi?acc_num=ucin1236277626.
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Thesis (M.A.)--University of Cincinnati, 2009.Advisors: Susanna Tong PhD (Committee Chair), Nicholas Dunning PhD (Committee Member), Kevin Raleigh PhD (Committee Member). Title from electronic thesis title page (viewed May 1, 2009). Includes abstract. Keywords: LUCC; Urban expansion; CA_Markov; MCE; EFLMR. Includes bibliographical references.
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Sun, Yu. "Simulating Future Land Use Change in the East Fork Little Miami River (EFLMR) Watershed in Ohio." University of Cincinnati / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1236277626.
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Efer, Thomas [Verfasser], Gerhard [Akademischer Betreuer] Heyer, Gerhard [Gutachter] Heyer, and Andreas [Gutachter] Henrich. "Graphdatenbanken für die textorientierten e-Humanities / Thomas Efer ; Gutachter: Gerhard Heyer, Andreas Henrich ; Betreuer: Gerhard Heyer." Leipzig : Universitätsbibliothek Leipzig, 2017. http://d-nb.info/1240697716/34.
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Barbosa, Maria Helena Neves. "Requalificação e gestão de ribeiras em áreas irrigadas mediterrânicas: aplicação ao perímetro de rega do EFMA." Doctoral thesis, ISA/UL, 2014. http://hdl.handle.net/10400.5/7346.
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Doutoramento em Restauro e Gestão Fluviais - Instituto Superior de Agronomia / Faculdade de Arquitectura / Instituto Superior TécnicoIn order to improve the drainage conditions of the several streams located in the Alqueva Multipurpose project, rehabilitation interventions (such as cleaning and reprofiling) are implemented. Little is known about the ecology of this streams, specially the analysis between these interventions' impact and vegetation recovery. Considering the legal requirements of Water Framework Directive, stream rehabilitation effects and overall effectiveness were assessed, and ecological deviations were analyzed between natural and agricultural streams (intervened and not intervened ones). Two types of streams were taken into account, small and large, so as to allow cause-effect relationships. To assess ecological functioning before and after interventions, and also to identify restoration standards between natural and agricultural streams, measurements expressed as categorized variables were performed, as well as statistical tests based on vegetation structure, riparian disturbance and morphological structure variables. The obtained results demonstrated that there are affections in both ecological structure and evolution after small stream reprofiling, as well as small deviations between not intervened and intervened streams and large deviations between agricultural and natural ones. Rehabilitation recommendations for future drainage regarding intervened streams are proposed.
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Perrier, Anthony. "efpR, un gène stabilisateur des fonctions de virulence et du métabolisme de la bactérie phytopathogène Ralstonia solanacearum." Thesis, Toulouse 3, 2018. http://www.theses.fr/2018TOU30352.
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Ralstonia solanacearum est une bactérie phytopathogène responsable du flétrissement bactérien chez plus de 250 espèces de plantes, dont des plantes à intérêt agronomique telles que la pomme de terre, la tomate ou encore l'arachide. Il a été observé à plusieurs reprises l'apparition de souches virulentes sur des hôtes précédemment décrits comme résistants. Afin de comprendre les bases moléculaires de l'adaptation à ses hôtes, une expérience d'évolution in planta a été réalisée dans mon équipe d'accueil. Pour cela, la souche GMI1000 de R. solanacearum a été maintenue dans la tige de plantes (variétés résistantes, sensibles ou tolérantes) pendant plus de 300 générations bactériennes. A la suite de cette expérience, il a été montré que plus de 80% des clones évolués présentaient un gain de fitness in planta par rapport à la souche ancestrale. Parmi 50 clones re- séquencés, 6 mutations indépendantes dans un même gène de fonction inconnue (renommé efpR) ont été observées, suggérant un fort parallélisme évolutif. L'implication de ces mutations dans le gain de fitness de la bactérie a été validée. Les objectifs de ma thèse ont été (1) de caractériser la fonction du gène efpR et (2) de mieux comprendre son implication dans le gain de fitness in planta de la bactérie. Des approches transcriptomiques et d'analyses métaboliques à haut débit (Biolog), couplées à des validations phénotypiques, ont permis de mettre en évidence que le gène efpR est un régulateur global à l'interface entre le métabolisme et la virulence. Nous avons aussi démontré que toutes les mutations apparues dans le gène efpR étaient des mutations 'perte de fonction' et que ces mutations induisaient un phénomène d'hétérogénéité phénotypique observable sur boite de pétri (2 types de colonies - 1 type sauvage et 1 type mutant). Nous avons mis en évidence un second gène RSc3149, homologue d'efpR, impliqué dans ce switch phénotypique. Le double mutant efpR-RSc3149 étant " verrouillé " dans la forme mutante, nous avons pu étudier l'avantage adaptatif pour la bactérie de générer de l'hétérogénéité phénotypique. [...]Ralstonia solanacearum is a bacterial plant pathogen responsible of the bacterial wilt disease on more than 250 plant species including agronomical crops such as potatoes, tomato and peanuts. It has been reported several times in the literature, the emergence of new pathogenic variants successfully able to infect and induce bacterial wilt disease on previously described resistant plants. To understand the molecular basis of R. solanacearum adaptation to its host, an evolution experiment has been performed in my host team. R. solanacearum has been kept during more than 300 bacterial generations into the stem of several plant species (susceptible, tolerant and resistant plants). At the end of the experiment, the in planta fitness of the derived clones has been tested compared to the ancestral WT strain, and more than 80% of the derived clones had a better fitness. Among them, 50 clones were re-sequenced. Interestingly, 6 independent mutations were found in the same gene of unknown function (renamed efpR), this strongly suggesting an evolutionary parallelism. Reverse genetics approaches confirmed that efpR was involved in the in planta fitness gain. The goals of my thesis were (1) to characterize the function of the efpR gene and (2) to better understand its role in the fitness gain of the bacterium. To do so, transcriptomic and metabolic analysis were performed followed by phenotypic validations. We demonstrated that EfpR is a global regulator of R. solanacearum controlling metabolic and virulence functions. We also demonstrated that all the mutations appeared during the evolution experiment were "loss of function" mutations, these mutations also induced a phenotypic heterogeneity phenomenon. Indeed, 2 types of colonies were observable on plates, one type similar to the colonies formed by the WT strain and another type less mucoid. We also highlighted another gene, the RSc3149 gene which is an efpR homolog involved in the phenotypic heterogeneity. Finaly, most of the efpR related phenotypes were strikingly similar of those associated with a well described regulator of the bacterium, the PhcA major regulator. We performed transcriptomic analysis of both regulons coupled with reporter gene fusions analysis to understand if there was a link between these two regulons and if we could position efpR in the regulatory network of R. solanacearum.[...]
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Monteiro, Chrystel Nunes. "Evolução da paisagem de montado na área abrangida pelo EFMA: caso de estudo no concelho de Beja." Master's thesis, Universidade de Évora, 2016. http://hdl.handle.net/10174/19428.
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A construção da Barragem de Alqueva foi durante anos considerada como
fundamental no desenvolvimento da sustentabilidade e modernização da agricultura no
Alentejo.
Por outro lado a sua representação paisagística sempre se agregou a imagens de uma
agricultura de sequeiro e extensiva mas hoje estamos perante uma agricultura regada e
intensiva, tendo as alterações na agricultura levantado questões relativas à transformação da
paisagem desta região.
Na atual campanha de rega do Alqueva está previsto no sistema global de rega do
projeto um total de 120 mil hectares de regadio, no entanto já existem estudos que
possibilitam o aumento desta área, cerca de 45 mil hectares além do projeto inicial (EDIA,
acesso em 23-2-2016)
Desta forma pretende-se analisar a transformação da ocupação do solo, numa área
abrangida pelo EFMA, o concelho de Beja, de modo a perceber como essa transformação ao
longo do tempo tem incidido sobre a paisagem e afetado o Montado; EVOLUÇÃO DA PAISAGEM DE MONTADO NA ÁREA ABRANGIDA PELO EFMA
C a s o d e E s t u d o n o C o n c e l h o d e B e j a
A B S T R A C T:
The construction of the Alqueva Dam was fundamental to the sustainable
development and modernization of agriculture in the Alentejo.
On the other hand its landscape representation has always added an image of an
extensive and cutting agriculture but today we are facing a irrigated and intensive
agriculture, having as changes in agriculture raised questions related to the transformation of
the landscape of the region.
In the current irrigation campaign of Alqueva is planned for a total of 120 thousand
hectares of irrigation, there are no studies that allow the increase of the area, about 45
thousand hectares beyond the initial project (EDIA, access On 23-2-2016)
In this way we intend to analyze a transformation of the land occupation, in an area
covered by the EFMA, the Beja municipality, in order to understand how this transformation
over time has affected a landscape and affected the Montado.
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Patrício, Marta Soraia Ribeiro. "A qualidade da água na Albufeira do Alvito e o empreendimento de fins múltiplos de Alqueva (EFMA)." Master's thesis, FCT - UNL, 2008. http://hdl.handle.net/10362/1943.
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Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de
Lisboa para obtenção do grau de Mestre em Engenharia do AmbienteO Empreendimento de Fins Múltiplos de Alqueva (EFMA) é um empreendimento que tem como objectivo principal a rega de cerca de 112 000 ha de terrenos que se distribuem entre as Bacias Hidrográficas do Guadiana e do Sado. A albufeira do Alvito integra-se no Subsistema de Rega Global de Alqueva sendo um dos reservatórios que receberá água provinda da albufeira do Alqueva. Esta albufeira será o principal centro distribuidor para todo o Baixo Alentejo. A presente dissertação pretende avaliar a influência da transferência da água do Alqueva na qualidade da água da albufeira do Alvito, com base no modelo matemático unidimensional Water Quality for River and Reservoir Systems. Para o cumprimento do objectivo proposto definiram-se dois cenários de simulação, com diferentes condições de exploração, um em regime natural e outro em regime de transferência de água. Os resultados obtidos por simulação permitiram identificar as principais alterações no sistema em termos de qualidade da água. No cômputo geral, os parâmetros simulados evidenciam uma degradação da qualidade da água após a adução de água proveniente da Bacia Hidrográfica do Guadiana. Atendendo às conclusões obtidas considera-se importante a formulação de estratégias que visem a mitigação dos potenciais efeitos decorrentes da transferência da água da Bacia Hidrográfica do Guadiana até à albufeira do Alvito.
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Silva, José Júnior Alves da. "Microscopia de força elétrica em amostra de óxido de grafeno." reponame:Repositório Institucional da UFC, 2013. http://www.repositorio.ufc.br/handle/riufc/8048.
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SILVA, José Júnior Alves da. Microscopia de força elétrica em amostra de óxido de grafeno. 2013. 100 f. Tese (Doutorado em Física) - Programa de Pós-Graduação em Física, Departamento de Física, Centro de Ciências, Universidade Federal do Ceará, Fortaleza, 2013.Submitted by Edvander Pires (edvanderpires@gmail.com) on 2014-05-13T21:31:02Z No. of bitstreams: 1 2013_tese_jjasilva.pdf: 30925308 bytes, checksum: b2e1379686008553b3699b7736b7335b (MD5)
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Carbon-based structures have played a major role in scientific and technological fields. This is due to the versatility of the element carbon, the pillar of organic chemistry, which can form a variety of structures (about 10 million compounds), besides being a basic constituent of all known life forms. Depending on the conditions, this phenomenal element can occur in several allotropic forms: from an extremely brittle material, such as graphite, so incredibly resistant materials such as diamond, carbon nanotubes and graphene. These graphitic materials have been studied extensively, and present unique properties and great potential for technological applications. Among these materials, graphene currently occupies the most prominent position by having special electronic and mechanical properties. The graphene oxide is a class of graphitic structure consisting essentially of a graphene layer decorated with epoxide and hydroxyl groups on the surface and carboxyl and carbonyl groups on the edges. Its stoichiometry depends strongly on the method of production. In addition the graphene oxide is one of the main routes for obtaining large-scale graphene also it has several interesting properties, which allow, for example, biological applications, since their functional groups make it very reactive, besides being easily dispersed in water. Many issues related to graphene oxide are yet unclear, as also its structure, training procedure and mechanisms of interaction. Thus, the electric force microscopy (EFM) was used as the main tool to study electrostatic properties of a graphene oxide sample obtained by a modified Hummer method. By means of a simplified model, it was possible to develop a method for the analysis of the EFM measurements and so determine the presence and the sign of the net charge of the sample. Furthermore it is possible to clarify the origin of the edge phenomenon observed in EFM experiments.
As estruturas a base de carbono tem um papel de grande importância nos campos da ciência e da tecnologia. Isso graças à versatilidade do elemento carbono, pilar da química orgânica, que consegue formar uma diversidade de estruturas (cerca de 10 milhões de compostos), além de ser um constituinte básico de toda forma de vida conhecida. Dependendo das condições de formação, este fenomenal elemento, pode se apresentar em diversas formas alotrópicas: desde um material extremamente frágil, como o grafite, até materiais incrivelmente resistentes como o diamante, nanotubos de carbono e o grafeno. Esses materiais grafíticos têm sido extensivamente estudados, apresentando propriedades únicas e grande potencial em aplicações tecnológicas. Dentre eles, o grafeno ocupa, atualmente, a posição de maior destaque por possuir propriedades mecânicas e eletrônicas diferenciadas. O óxido de grafeno é uma classe de estruturas grafíticas constituída basicamente de uma camada de grafeno decorada com grupos epóxido e hidroxila na superfície e grupos carboxílicos e carbonila nas bordas. A sua estequiometria depende fortemente do método de obtenção. Esse material, além de ser uma das principais rotas para a obtenção em larga escala do grafeno, também apresenta diversas propriedades interessantes, que possibilitam, por exemplo, aplicações biológicas, uma vez que seus grupos funcionais o tornam bastante reativo além de ser facilmente dispersado em água. Muitas questões relacionadas ao óxido de grafeno ainda não estão bem esclarecidas, como sua própria estrutura, processo de formação e mecanismos de interação. Nesse sentido, foi utilizada, como principal ferramenta, a microscopia de força elétrica (EFM) para estudar propriedades eletrostáticas de uma amostra de óxido de grafeno obtida utilizando-se um método de Hummer modificado. Por meio de um modelo simplificado, foi possível desenvolver um método para análise das medições de EFM e assim determinar a presença e o sinal da carga líquida da amostra. Além de ser possível esclarecer a origem do fenómeno de borda observado nos experimentos de EFM.
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Özaydın, Nurcan Gökırmak Münire. "Koah akut atağında farklı steroid dozlarının solunum fonksiyonları, arter kan gazı, dispne skalası, efor kapasitesi ve yaşam kalitesi üzerine etkileri /." Isparta: SDÜ Tıp Fakültesi, 2006. http://tez.sdu.edu.tr/Tezler/TT00267.pdf.
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Silva, Josà JÃnior Alves da. "Microscopia de forÃa elÃtrica em amostra de Ãxido de grafeno." Universidade Federal do CearÃ, 2013. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=11333.
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FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgicoAs estruturas a base de carbono tem um papel de grande importÃncia nos campos da ciÃncia e da tecnologia. Isso graÃas à versatilidade do elemento carbono, pilar da quÃmica orgÃnica, que consegue formar uma diversidade de estruturas (cerca de 10 milhÃes de compostos), alÃm de ser um constituinte bÃsico de toda forma de vida conhecida. Dependendo das condiÃÃes de formaÃÃo, este fenomenal elemento, pode se apresentar em diversas formas alotrÃpicas: desde um material extremamente frÃgil, como o grafite, atà materiais incrivelmente resistentes como o diamante, nanotubos de carbono e o grafeno. Esses materiais grafÃticos tÃm sido extensivamente estudados, apresentando propriedades Ãnicas e grande potencial em aplicaÃÃes tecnolÃgicas. Dentre eles, o grafeno ocupa, atualmente, a posiÃÃo de maior destaque por possuir propriedades mecÃnicas e eletrÃnicas diferenciadas. O Ãxido de grafeno à uma classe de estruturas grafÃticas constituÃda basicamente de uma camada de grafeno decorada com grupos epÃxido e hidroxila na superfÃcie e grupos carboxÃlicos e carbonila nas bordas. A sua estequiometria depende fortemente do mÃtodo de obtenÃÃo. Esse material, alÃm de ser uma das principais rotas para a obtenÃÃo em larga escala do grafeno, tambÃm apresenta diversas propriedades interessantes, que possibilitam, por exemplo, aplicaÃÃes biolÃgicas, uma vez que seus grupos funcionais o tornam bastante reativo alÃm de ser facilmente dispersado em Ãgua. Muitas questÃes relacionadas ao Ãxido de grafeno ainda nÃo estÃo bem esclarecidas, como sua prÃpria estrutura, processo de formaÃÃo e mecanismos de interaÃÃo. Nesse sentido, foi utilizada, como principal ferramenta, a microscopia de forÃa elÃtrica (EFM) para estudar propriedades eletrostÃticas de uma amostra de Ãxido de grafeno obtida utilizando-se um mÃtodo de Hummer modificado. Por meio de um modelo simplificado, foi possÃvel desenvolver um mÃtodo para anÃlise das mediÃÃes de EFM e assim determinar a presenÃa e o sinal da carga lÃquida da amostra. AlÃm de ser possÃvel esclarecer a origem do fenÃmeno de borda observado nos experimentos de EFM.
Carbon-based structures have played a major role in scientific and technological fields. This is due to the versatility of the element carbon, the pillar of organic chemistry, which can form a variety of structures (about 10 million compounds), besides being a basic constituent of all known life forms. Depending on the conditions, this phenomenal element can occur in several allotropic forms: from an extremely brittle material, such as graphite, so incredibly resistant materials such as diamond, carbon nanotubes and graphene. These graphitic materials have been studied extensively, and present unique properties and great potential for technological applications. Among these materials, graphene currently occupies the most prominent position by having special electronic and mechanical properties. The graphene oxide is a class of graphitic structure consisting essentially of a graphene layer decorated with epoxide and hydroxyl groups on the surface and carboxyl and carbonyl groups on the edges. Its stoichiometry depends strongly on the method of production. In addition the graphene oxide is one of the main routes for obtaining large-scale graphene also it has several interesting properties, which allow, for example, biological applications, since their functional groups make it very reactive, besides being easily dispersed in water. Many issues related to graphene oxide are yet unclear, as also its structure, training procedure and mechanisms of interaction. Thus, the electric force microscopy (EFM) was used as the main tool to study electrostatic properties of a graphene oxide sample obtained by a modified Hummer method. By means of a simplified model, it was possible to develop a method for the analysis of the EFM measurements and so determine the presence and the sign of the net charge of the sample. Furthermore it is possible to clarify the origin of the edge phenomenon observed in EFM experiments.
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Hodge, Toni Ann. "Accreditation of Business Schools: An Explanatory Multiple-Case Study of their Motivations." Thesis, University of Canterbury. Management, 2010. http://hdl.handle.net/10092/3755.
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The commitment required of a university or business school to gain international
accreditation is significant, both in dollar terms and staff time. This thesis seeks to explain the motivations for business schools to seek accreditation with three major accrediting bodies, AACSB International, EFMD and AMBA, using a multiple-case study methodology underpinned by the frameworks of institutional isomorphism, bandwagon pressures and information asymmetry.
Interviews were carried out with 17 business school deans; five deans of accredited schools in Europe, five deans of accredited schools in the United States of America and seven
business school deans in New Zealand. All the New Zealand schools were either accredited, formally in the process of seeking accreditation or about to enter the application stage. The results provide supporting evidence for the notion that business schools are seeking
accreditation in order to achieve legitimacy benefits rather than performance benefits, and that intangible benefits are seen as having more importance than the costs involved with achieving accreditation. It was also found that where the focus is at an international level, accreditation is found to be underpinned by information asymmetries whereby schools are seeking to gain legitimacy by providing signals to the market regarding their quality. At a regional or national level information regarding quality is more well known and, instead, isomorphic and bandwagon pressures become evident as the pathway towards legitimacy. This study will be of value to business school deans in understanding the forces they are being subjected to when considering the value of seeking international accreditation. The results provide an understanding of why, in the absence of a formal business case, a school may consider such a move, or may have entered the process without the hard data that
identifies the costs and estimates the benefits in a measurable way. In this regard it will also be of value to all staff of business schools, and of the wider organisation, to understand the
phenomenon that is accreditation.
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Calavalle, Francesco. "Caratterizzazione microscopica di un transistor organico a effetto di campo." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amslaurea.unibo.it/7812/.
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Negli ultimi anni uno dei settori di ricerca più interessanti in ambito tecnologico è sicuramente quello dell'elettronica organica. Lo sviluppo è spinto dai vantaggi che portano i dispositivi basati su materiali organici: bassi costi di produzione, facilità di fabbricazione su grandi aree e flessibilità.
In questa tesi andiamo ad esaminare un transistor organico a effetto di campo (OFET) dal punto di vista macroscopico e microscopico, cercando di mettere in relazione le sue caratteristiche morfologiche ed elettriche.
Il dispositivo sottoposto ai test è un OFET realizzato con TIPS-pentacene come semiconduttore. Dai risultati ottenuti si evince che le prestazioni elettriche del transistor sono fortemente legate alla microstruttura assunta dal materiale organico durante la deposizione.
I primi due capitoli illustrano i principi di funzionamento degli OFET e la tecnica SPM (scanning probe microscopy) utilizzata per l'indagine microscopica. Il terzo e quarto capitolo descrivono rispettivamente gli apparati sperimentali e i risultati ottenuti dall'indagine su due aree diverse del dispositivo.
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Xu, JiaPeng. "A Novel Nanoparticle Manipulation Method Using Atomic Force Microscope." The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1243987021.
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Mottaghizadeh, Alireza. "Non-conventional insulators : metal-insulator transition and topological protection." Thesis, Paris 6, 2014. http://www.theses.fr/2014PA066652/document.
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Ce manuscrit présente une étude expérimentale de phase isolante non-conventionnelle, l'isolant d'Anderson, induit par le désordre, l'isolant de Mott, induit par les interactions de Coulomb, et les isolants topologiques.Dans une première partie du manuscrit, je décrirais le développement d'une méthode pour étudier la réponse de charge de nanoparticules par Microscopie à Force Electrostatique (EFM). Cette méthode a été appliquée à des nanoparticules de magnétite (Fe3O4), un matériau qui présente une transition métal-isolant, i.e. la transition de Verwey, lors de son refroidissement en dessous d'une température TV~120 K.Dans une seconde partie, ce manuscrit présente une étude détaillée de l'évolution de la densité d'états au travers de la transition métal-isolant entre un isolant de type Anderson-Mott et une phase métallique dans le matériau SrTiO3, et ceci, en fonction de la concentration de dopants, les lacunes d'oxygènes. Nous avons trouvé que dans un dispositif memoresistif de type Au-SrTiO3-Au, la concentration de dopants pouvait être ajustée par migration des lacunes d'oxygènes à l'aide d'un champ. Dans cette jonction tunnel, l'évolution de la densités d'états au travers de la transition métal-isolant peut être étudiée de façon continue. Finalement, dans une troisième partie, le manuscrit présente le développement d'une méthode pour la microfabrication d'anneaux de Aharonov-Bohm avec l'isolant topologique, Bi2Se3, déposée par épitaxie à jet moléculaire. Des résultats préliminaires sur les propriétés de transport quantique de ces dispositifs seront présentésThis manuscript presents an experimental study of unconventional insulating phases, which are the Anderson insulator, induced by disorder, the Mott insulator, induced by Coulomb interactions, and topological insulators.In a first part of the manuscript, I will describe the development of a method to study the charge response of nanoparticles through Electrostatic Force Microscopy (EFM). This method has been applied to magnetite Fe3O4 nanoparticles, a material that presents a metal-insulator transition, i.e. the Verwey transition, upon cooling the system below a temperature Tv=120K. In a second part, this manuscript presents a detailed study of the evolution of the Density Of States (DOS) across the metal-insulator transition between an Anderson-Mott insulator and a metallic phase in the material SrTiO3 and this, as function of dopant concentration, i.e. oxygen vacancies. We found that in this memristive type device Au-SrTiO3-Au, the dopant concentration could be fine-tuned through electric-field migration of oxygen vacancies. In this tunnel junction device, the evolution of the DOS can be followed continuously across the metal-insulator transition. Finally, in a third part, the manuscript presents the development of a method for the microfabrication of Aharonov-Bohm rings with the topological insulator material, Bi2Se3, grown by molecular beam epitaxy. Preliminary results on the quantum transport properties of these devices will be presented
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Wang, Debin. "Thermochemical nanolithography fabrication and atomic force microscopy characterization of functional nanostructures." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/34776.
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This thesis presents the development of a novel atomic force microscope (AFM) based nanofabrication technique termed as thermochemical nanolithography (TCNL). TCNL uses a resistively heated AFM cantilever to thermally activate chemical reactions on a surface with nanometer resolution. This technique can be used for fabrication of functional nanostructures that are appealing for various applications in nanofluidics, nanoelectronics, nanophotonics, and biosensing devices.
This thesis research is focused on three main objectives. The first objective is to study the fundamentals of TCNL writing aspects. We have conducted a systematic study of the heat transfer mechanism using finite element analysis modeling, Raman spectroscopy, and local glass transition measurement. In addition, based on thermal kinetics analysis, we have identified several key factors to achieve high resolution fabrication of nanostructures during the TCNL writing process.
The second objective is to demonstrate the use of TCNL on a variety of systems and thermochemical reactions. We show that TCNL can be employed to (1) modify the wettability of a polymer surface at the nanoscale, (2) fabricate nanoscale templates on polymer films for assembling nano-objects, such as proteins and DNA, (3) fabricate conjugated polymer semiconducting nanowires, and (4) reduce graphene oxide with nanometer resolution.
The last objective is to characterize the TCNL nanostructures using AFM based methods, such as friction force microscopy, phase imaging, electric force microscopy, and conductive AFM. We show that they are useful for in situ characterization of nanostructures, which is particularly challenging for conventional macroscopic analytical tools, such as Raman spectroscopy, IR spectroscopy, and fluorescence microscopy.
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Stenberg, Joel. "Fuskbank för hantering av e-fakturaflöden." Thesis, Mittuniversitetet, Institutionen för informationsteknologi och medier, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-17031.
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Internet som är något som de flesta använder sig av, blir allt mer populärt att kombinera internetanvändning när det gäller att betala räkningar. Elektronisk faktura är ett sätt att presentera faktura elektroniskt. Syftet med detta projekt har varit att skapa en fuskbank som kan interagera med e-fakturaflöden och motsvara en certifierad teknisk distributör samt presentatörsbank. Fuskbanken tar emot filer av filformatet EFB som bland annat innehåller betalrader med tillhörande länkar till fakturaspecifikation. EFB-filen innehåller information som visas i en internetbank för en privatpersons e-faktura. Fuskbanken ska kunna skapa två filer av filformatet EFBR och EFA. EFBR är en återredovisningsfil för EFB, och EFA används till avanmälning av e-faktura. Fuskbankens uppgift är att parsa en EFB-fil för att sedan sätta in den i en databas. Därefter ska en parsad fil visas i ett webbgränssnitt. Utifrån ett webbgränssnitt ska det vara möjligt att skapa EFBR- och EFA-filer. Vid skapandet av fuskbanken användes Java 6 som programmeringsspråk och en applikationsserver vid namn JBoss application server 7. MySQL användes för databas och för webbgränssnitt användes Primefaces. Resultatet är en fuskbank som kan interagera med e-fakturaflöden och visa var i en parsad EFB-fil ett formatfel uppstod. Av de mätningar som gjorts framkommer det att tiden det tar att parsa en EFB-fil är skäligt. Fuskbanken kommer endast användas i testmiljö varför den information som sätts in i en databas reflekterar inte riktiga efakturakunders fakturor.
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Bartolucci, Alberto. "Morphological characterization of ZnS thin films for photovoltaic applications." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amslaurea.unibo.it/10540/.
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Le celle solari a film sottile sono tra le alternative più promettenti nel campo fotovoltaico. La ricerca di materiali non tossici ed economici per la passivazione delle superfici è di fondamentale importanza. Il presente è uno studio sulla morfologia di film sottili di ZnS. I campioni analizzati sono stati cresciuti tramite DC sputtering a diversa potenza (range 50-150W) per studiare le connessioni tra condizioni di deposizione e proprietà strutturali. Lo studio è stato condotto mediante acquisizione di mappe AFM. E' stata effettuata un'analisi dei buchi (dips) in funzione della potenza di sputtering, per individuare il campione con la minore densità di dips in vista di applicazioni in celle solari a film sottile. I parametri strutturali, quali la rugosità superficiale e la lunghezza di correlazione laterale sono stati determinati con un'analisi statistica delle immagini. La densità e dimensione media dei grani sono state ricavate da una segmentazione delle immagini. Le analisi sono state svolte su due campioni di ZnO per fini comparativi. Tramite EFM sono state ottenute mappe di potenziale di contatto. Tramite KPFM si è valutata la differenza di potenziale tra ZnS e un layer di Al depositato sulla superficie. La sheet resistance è stata misurata con metodo a quattro punte. Dai risultati la potenza di sputtering influenza la struttura superficiale, ma in maniera non lineare. E' stato individuato il campione con la minore rugosità e densità di dips alla potenza di 75 W. Si è concluso che potenze troppo grandi o piccole in fase di deposizione promuovono il fenomeno di clustering dei grani e di aumentano la rugosità e densità di dips. E' emersa una corrispondenza diretta tra morfologia e potenziale di contatto alla superficie. La differenza di potenziale tra Al e ZnS è risultata inferiore al valore noto, ciò può essere dovuto a stati superficiali indotti da ossidi. Il campione risulta totalmente isolante.
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Castañeda, Nakano Natahlie Yahaida, and Mestanza Andrea Elizabeth Olano. "Diagnóstico de las empresas familiares de la ciudad de Chiclayo en cuanto a aplicar un modelo de empresas familiarmente responsables (EFR). Un estudio exploratorio." Bachelor's thesis, Universidad Católica Santo Toribio de Mogrovejo, 2015. http://hdl.handle.net/20.500.12423/74.
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En la actualidad lograr un equilibrio entre las diversas actividades de un individuo podría resultar complicado. La conciliación entre la vida personal, familiar y laboral es un tema de novedad, que debería empezar a ser de gran importancia en las empresas y en consecuencia en su gestión. La presente tesis se fundamenta en los indicadores de Empresa Familiarmente Responsable (EFR), estudiado en sus inicios en España por la Dra. Nuria Chinchilla, con base en escalas previamente validadas que forman parte del IESE, se realizó un diagnóstico empírico situacional en las empresas familiares de Chiclayo, comprendidas en este estudio acerca de su nivel de desarrollo en cuanto a aplicar un modelo de empresa familiarmente responsable, mostrando los diferentes aspectos que intervienen en el desarrollo de la conciliación entre vida familiar y laboral. Los resultados muestran que solo una empresa aplica en su totalidad estos parámetros, es decir más del 80 %, a pesar de que por su naturaleza debería añadir más interés por sus trabajadores ya que se constituyen como familiares, estas no están fomentando una conciliación entre vida laboral y familiar en su totalidad. El principal aporte de la tesis es que a través de este diagnóstico se puede obtener información referencial acerca de la situación actual de las empresas familiares de la ciudad de Chiclayo comprendidas en este estudio, en cuanto a aplicar el modelo de empresa familiarmente responsable.Tesis
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Castañeda, Nakano Natahlie Yahaida, Mestanza Andrea Elizabeth Olano, Nakano Natahlie Yahaida Castañeda, and Mestanza Andrea Elizabeth Olano. "Diagnóstico de las empresas familiares de la ciudad de Chiclayo en cuanto a aplicar un modelo de empresas familiarmente responsables (EFR). Un estudio exploratorio." Bachelor's thesis, Universidad Católica Santo Toribio de Mogrovejo, 2015. http://tesis.usat.edu.pe/jspui/handle/123456789/497.
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Trabajo de suficiencia profesionalEn la actualidad lograr un equilibrio entre las diversas actividades de un individuo podría resultar complicado. La conciliación entre la vida personal, familiar y laboral es un tema de novedad, que debería empezar a ser de gran importancia en las empresas y en consecuencia en su gestión. La presente tesis se fundamenta en los indicadores de Empresa Familiarmente Responsable (EFR), estudiado en sus inicios en España por la Dra. Nuria Chinchilla, con base en escalas previamente validadas que forman parte del IESE, se realizó un diagnóstico empírico situacional en las empresas familiares de Chiclayo, comprendidas en este estudio acerca de su nivel de desarrollo en cuanto a aplicar un modelo de empresa familiarmente responsable, mostrando los diferentes aspectos que intervienen en el desarrollo de la conciliación entre vida familiar y laboral. Los resultados muestran que solo una empresa aplica en su totalidad estos parámetros, es decir más del 80 %, a pesar de que por su naturaleza debería añadir más interés por sus trabajadores ya que se constituyen como familiares, estas no están fomentando una conciliación entre vida laboral y familiar en su totalidad. El principal aporte de la tesis es que a través de este diagnóstico se puede obtener información referencial acerca de la situación actual de las empresas familiares de la ciudad de Chiclayo comprendidas en este estudio, en cuanto a aplicar el modelo de empresa familiarmente responsable.
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Woodard, Tracy, Jeff Vetter, and Jason Rodzinak. "Development of a Subminiature Enhanced Flight Termination Receiver." International Foundation for Telemetering, 2011. http://hdl.handle.net/10150/595659.
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ITC/USA 2011 Conference Proceedings / The Forty-Seventh Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2011 / Bally's Las Vegas, Las Vegas, NevadaAs the size of missiles and UAVs shrink, so does the volume available for the Flight Termination System (FTS). Small, light weight FTS systems open up applications not possible with the larger and heavier conventional FTS systems. This paper presents a novel approach for the design, implementation and test of a subminiature Flight Terminate System Receiver for use in the Subminiature Flight Safety System (SFSS). This receiver implements the new digital-based Enhanced Flight Termination System (EFTS) protocol, while maintaining a volume of less than 1 cubic inch with power consumption of less than 2 watts. Combining all of the necessary functionality into a small package while meeting the rigorous requirements of the Range Commanders Council (RCC) specifications (EMI, vibration and shock) presented significant challenges. The Subminiature Enhanced Flight Termination Receiver used in the SFSS has been named the "SEFTR".
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Lanzoni, Evandro Martin. "Electric force microscopy techniques on GaAs mesoscopic structures." Universidade Estadual Paulista (UNESP), 2018. http://hdl.handle.net/11449/154116.
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As técnicas de microscopia de sonda Kelvin (KPFM) e de microscopia de força eletrostática (EFM) são amplamente utilizadas para analisar a distribuição do potencial de superfície, porém com pouca aplicação em nanoestruturas semicondutoras auto-organizadas embutidas em um substrato. Neste trabalho, investigamos diretamente o acúmulo de carga dentro de estruturas mesoscópicas de GaAs (MGS) [1]. As estruturas são fabricadas através do crescimento sobreposto de um modelo de nano orifícios usando epitaxia de feixe molecular. Para tal, uma combinação de desoxidação assistida por Ga e ataque químico por gotículas localizadas foram utilizadas para criar orifícios iniciais com uma profundidade de ca. 10 a 15nm, que são posteriormente cobertos com 15nm de barreira AlxGax-1As e GaAs com 1nm, 2nm, 5nm, 10nm de espessura. Microscopia de força atômica e microscopia eletrônica de transmissão mostraram que a forma do orifício é preservada durante o crescimento de AlGaAs. Em seguida, esses orifícios são preenchidos com GaAs formando uma estrutura alongada sobre o buraco [1]. Investigamos o potencial de superfície local e a distribuição das cargas nestas estruturas com a técnica KPFM de passagem única. Portanto, uma voltagem AC de 5 V é aplicada a uma ponta metalizada e varremos a amostra no modo de contato intermitente. Observamos uma clara diferença de potencial na região central da estrutura, onde esperamos o furo preenchido. Então, um estudo sistemático com a técnica de KPFM mostrou a influência no acúmulo de carga quando a espessura de GaAs é alterada, bem como, quando modificamos a concentração de Al na barreira de AlGaAs. O cálculo simulando um poço de potencial com barreiras semi-finitas e finitas mostrou que não ocorre acúmulo de carga quando a espessura do GaAs é menor que 1,5 nm, corroborando com nossos resultados. Simulações do diagrama de banda e da densidade de elétron da estrutura permitem atribuir o acumulo de carga observado, aos diferentes níveis de energia da estrutura mesoscópica de GaAs em comparação com as camadas de GaAs circundantes.
Kelvin probe force microscopy and electric force microscopy techniques are widely used to analyze the distribution of the surface potential with little application to self-assembled semiconductor nanostructures embedded into a substrate. In this work, we directly investigate the charge accumulation inside mesoscopic GaAs structures [1]. The structures are fabricated by overgrowth of a nanohole template using molecular beam epitaxy. Therefore, a combination of Ga assisted deoxidation and local droplet etching is used to create initial holes with a depth of ca. 10 to 15nm, which are covered subsequently with 15nm of AlxGax-1As barrier and GaAs caps with 1nm, 2nm, 5nm, 10nm thicknesses. Atomic force microscopy and transmission electron microscopy results showed that the hole shape is preserved during the AlGaAs overgrowth. Then filled with GaAs forming an elongated mount over the hole [1]. We investigate the local potential and the charge distribution in these structures with a single pass Kelvin probe force microscopy technique. Therefore, an AC voltage of 5 V is applied to a metalized tip and scanned in tapping mode over the sample. We observed a clear potential difference in Kelvin probe force microscopy measurements in the middle of the structure, where we expect a filled hole. We systematically study by Kelvin probe force microscopy the influence on the charge accumulation when the GaAs thickness is changed, as well as the Al concentration in the AlGaAs barrier. Calculation of the particle in the box for semi-finite and finite barriers were done and show that no charge accumulation is observed for GaAs thickness lower than 1.5nm in the semi-finite barrier, corroborating with our results. Simulations of band gap and electron wavefunction of the structure allow us to ascribe the charge accumulation observed, to the different confinement of carriers inside of the unstrained mesoscopic GaAs structure compared to the surrounding GaAs layers.
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Li, Xiaxi. "In situ characterization of electrochemical processes of solid oxide fuel cells." Diss., Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/54256.
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Solid oxide fuel cells (SOFCs) represent a next generation energy source with high energy conversion efficiency, low pollutant emission, good flexibility with a wide variety of fuels, and excellent modularity suitable for distributed power generation. As an electrochemical energy conversion device, SOFC’s performance and reliability depend sensitively on the catalytic activity and stability of the electrode materials. To date, however, the development of electrode materials and microstructures is still based largely on trial-and-error methods because of inadequate understanding of the mechanisms of the electrode processes. Identifying key descriptors/properties of electrode materials or functional heterogeneous interfaces, especially under in situ conditions, may provide guidance to the design of electrode materials and microstructures. This thesis aims to gain insight into the electrochemical and catalytic processes occurring on the electrode surfaces using unique characterization tools with superior sensitivity, high spatial resolution, and excellent surface specificity applicable under in situ/operando conditions.
Carbon deposition on nickel-based anodes is investigated with in situ Raman spectroscopy and SERS. Analysis shows a rapid nucleation of carbon deposition upon exposure to small amount of propane. Such nucleation process is sensitive to the presence of surface coating (e.g., GDC) and the concentration of steam. In particular, operando analysis of the Ni-YSZ boundary indicates special function of the interface for coking initiation and reformation.
The coking-resistant catalysts (BaO, BZY, and BZCYYb) are systematically studied using in situ Raman spectroscopy, SERS, and EFM. In particular, time-resolved Raman analysis of the surface functional groups (-OH, -CO3, and adsorbed carbon) upon exposure to different gas atmospheres provides insight into the mechanisms related to carbon removal. The morphology and distribution of early stage carbon deposition are investigated with EFM, and the impact of BaO surface modification is evaluated.
The surface species formed as a result of sulfur poisoning on nickel-based anode are examined with SERS. To identify the key factors responsible for sulfur tolerance, model cells with welldefined electrode-electrolyte interfaces are systematically studied. The Ni-BZCYYb interface exhibits superior sulfur tolerance.
The oxygen reduction kinetics on LSCF, a typical cathode material of SOFC, is studied using model cells with patterned electrodes. The polarization behaviors of these micro- electrodes, as probed using a micro-probe impedance spectroscopy system, were correlated with the systematically varied geometries of the electrodes to identify the dominant paths for oxygen reduction under different electrode configurations. Effects of different catalyst modifications are also evaluated to gain insight into the mechanisms that enhance oxygen reduction activity.
The causes of performance degradation of LSCF cathodes over long term operation are investigated using SERS. Spectral features are correlated with the formation of surface contamination upon the exposure to air containing Cr vapor, H2O, and CO2. Degradation in cathode performance occurs under normal operating conditions due to the poisoning effect of Cr from the interconnect between cells and the high operating temperature. The surface-modified LSCF cathode resists surface reactions with Cr vapor that impairs electrode performance, suggesting promising ways to mitigate performance degradation.
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Riedel, Clément. "Propriétés diélectrique et mécanique des polymères aux échelles macro et nanoscopiques." Phd thesis, Université Montpellier II - Sciences et Techniques du Languedoc, 2010. http://tel.archives-ouvertes.fr/tel-00582827.
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Le but de cette thèse était tout d'abord d'étudier les théories physiques qui décrivent la dynamique des polymères à l'échelle macroscopique. Le modèle de Rouse et la théorie d'enchevêtrement de P-G. de Gennes décrivent la dynamique des polymères non enchevêtrés et enchevêtrés, respectivement. Nous avons étudié les différentes transitions entre ces deux régimes en utilisant deux techniques expérimentales : Spéctroscopie dielectrique large bande et rhéologie. Un test complet du modèle de Rouse à été effectué en comparant les prédictions de ce modèle pour la dépendance en fréquence de la permittivité diélectrique et du module de cisaillement aux données expérimentales. Les effets d'enchevêtrement sur les spectres diélectriques ont été discutés. Nous avons ensuite développé des méthodes basées sur la microscopie à force électrostatique afin d'étudier les propriétés diélectriques locales. En utilisant une simulation numérique basée sur la Méthode des Charges Equivalentes, nous avons quantifié la constante diélectrique à partir de la mesure du gradient de force crée par un potentiel statique entre une pointe et un diélectrique. Cette méthode permet d'imager la constante diélectrique avec une résolution spatial de 40 nm. Le retard de phase de la composante en 2 omega de la force ou du gradient de force crée par un voltage alternatif est relié aux pertes diélectriques. Nous avons développé un mode d'imagerie des pertes diélectriques. Cette méthode simple pourrait être appliqué en biologie ou matière molle en générale afin d'étudier des variations locales de constantes dielectriques.
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Chmayssani, Toufic. "Modulation sur les canaux vocodés." Phd thesis, Université Paris-Est, 2010. http://tel.archives-ouvertes.fr/tel-00587629.
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Les canaux vocodés sont les canaux de communications dédiés à la voix et dans lesquels le signal traverse divers équipements destinés au transport de la voix tels que des codeurs de parole, des détecteurs d'activité vocale (VAD), des systèmes de transmission discontinue (DTX). Il peut s'agir de systèmes de communications téléphoniques filaires ou mobiles (réseaux cellulaires 2G/3G, satellites INMARSAT...) ou de voix sur IP. Les codeurs de parole dans les normes récentes pour les réseaux de téléphonie mobiles ou de voix sur IP font appel à des algorithmes de compression dérivés de la technique CELP (Code Excited Linear Prediction) qui permettent d'atteindre des débits de l'ordre de la dizaine de Kb/s bien inférieurs aux codeurs des réseaux téléphoniques filaires (typiquement 64 ou 32 Kb/s). Ces codeurs tirent leur efficacité de l'utilisation de caractéristiques spécifiques aux signaux de parole et à l'audition humaine. Aussi les signaux autres que la parole sont-ils généralement fortement distordus par ces codeurs. La transmission de données sur les canaux vocodés peut être intéressante pour des raisons liées à la grande disponibilité des canaux dédiés à la voix et pour des raisons de discrétion de la communication (sécurité). Mais le signal modulé transmis sur ces canaux vocodés est soumis aux dégradations causées par les codeurs de parole, ce qui impose des contraintes sur le type de modulation utilisé. Cette thèse a porté sur la conception et l'évaluation de modulations permettant la transmission de données sur les canaux vocodés. Deux approches de modulations ont été proposées pour des applications correspondant à des débits de transmission possibles assez différents. La principale application visée par la thèse concerne la transmission de parole chiffrée, transmission pour laquelle le signal de parole est numérisé, comprimé à bas débit par un codeur de parole puis sécurisé par un algorithme de cryptage. Pour cette application, nous nous sommes focalisés sur les réseaux de communications utilisant des codeurs CELP de débits supérieurs à la dizaine de Kb/s typiquement les canaux de communication mobiles de deuxième ou troisième génération. La première approche de modulation proposée concerne cette application. Elle consiste à utiliser des modulations numériques après optimisation de leurs paramètres de façon à prendre en compte les contraintes imposées par le canal et à permettre des débits et des performances en probabilité d'erreur compatibles avec la transmission de parole chiffrée (typiquement un débit supérieur à 1200 b/s avec un BER de l'ordre de 10-3). Nous avons montré que la modulation QPSK optimisée permet d'atteindre ces performances. Un système de synchronisation est aussi étudié et adapté aux besoins et aux contraintes du canal vocodé. Les performances atteintes par la modulation QPSK avec le système de synchronisation proposé, ainsi que la qualité de la parole sécurisée transmise ont été évalués par simulation et validés expérimentalement sur un canal GSM réel grâce à un banc de test développé dans la thèse.La deuxième approche de modulation a privilégié la robustesse du signal modulé lors de la transmission à travers un codeur de parole quelconque, même un codeur à bas débit tels que les codeurs MELP à 2400 ou 1200 b/s. Dans ce but, nous avons proposé une modulation effectuée par concaténation de segments de parole naturelle associée à une technique de démodulation qui segmente le signal reçu et identifie les segments de parole par programmation dynamique avec taux de reconnaissance élevé. Cette modulation a été évaluée par simulation sur différents codeurs de parole. Elle a aussi été testée sur des canaux GSM réels. Les résultats obtenus montrent une probabilité d'erreur très faible quelque soit le canal vocodé et le débit des codeurs de parole utilisés mais pour des débits possibles relativement faibles. Les applications envisageables sont restreintes à des débits typiquement inférieurs à 200 b/s.Enfin nous nous sommes intéressés aux détecteurs d'activité vocale dont l'effet peut-être très dommageable pour les signaux de données. Nous avons proposé une méthode permettant de contrer les VAD utilisés dans les réseaux GSM. Son principe consiste à rompre la stationnarité du spectre du signal modulé, stationnarité sur laquelle s'appuie le VAD pour décider que le signal n'est pas de la parole
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Veaux, Christophe. "Étude de traitements en réception pour l'amélioration de la qualité de la parole : application au GSM." Paris, ENST, 2005. http://www.theses.fr/2005ENST0006.
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Dans les communications radio-mobiles, la qualité de la parole est fortement impactée par les erreurs résiduelles en sortie du décodeur canal. Celles-ci résultent des paquets d'erreurs introduits par le canal radio alors que les contraintes de complexité limitent les performances du codage canal. Parallèlement, ces mêmes contraintes font qu'il subsiste une redondance résiduelle en sortie du codeur de parole. Cette redondance résiduelle fournit une information a priori qui peut être exploitée au niveau du décodeur de parole pour minimiser l'erreur d'estimation des paramètres transmis, ou au niveau du décodeur canal pour minimiser le taux d'erreurs résiduelles. Nous étudions chacune de ces approches ainsi que leur combinaison dans le cas du GSM EFR. Au niveau du décodeur parole, nous modélisons la redondance résiduelle des paramètres du codeur à l'aide de mélanges de gaussiennes ce qui permet de réduire la complexité de l'estimation par rapport aux méthodes existantes et délivre une information plus riche sur la redondance résiduelle. Au décodeur canal, nous améliorons la prise en compte de la redondance résiduelle entre les bits d'une même trame par une technique de prédiction le long des chemins du treillis. Ces approches sont évaluées sur des simulations de transmission par l'algorithme PESQ de mesure objective de la qualité vocale. Le décodeur de parole exploitant la redondance résiduelle apparaît supérieur au décodeur classique du GSM EFR avec masquage d'erreur. En revanche, les performances du décodeur canal exploitant la redondance résiduelle sont sensibles à la correspondance choisie ente les éléments du dictionnaire de quantification et leur étiquetage binaireIn digital mobile radio systems, the speech quality can be severly degraded if the channel decoder produces residual bit errors due to heavy burst errors on the radio path. On the other hand, in most speech coding schemes some residual redundancy remains because of complexity and delay limitations. A solution for improving the speech quality consists in using a priori information based on source residual redundancy at the receiver side. In one approach, a priori information is used at the source decoder to perform optimal estimation of transmitted codec parameters. In another approach, a priori information is used at the channel decoder in oder to minimize the residual bit errors rate. We study both approaches and apply them to the GSM EFR. At the speech decoder level, we model the residual redundancy of speech codec parameters by using Gaussian mixtures. This model reduces the complexity when compared to state-of-art methods and provides a better representation of residual redundancy. At the channel decoder level, we introduce an efficient method to exploit intra-frame bit redundancy during the channel decoding process. In this method, the value of the bit being decoded is predicted from the bits already decoded along the treillis path. These methods are evaluated on simulations of radio transmission by an objective measure of speech quality. In all cases, the performance of the speech decoder using our residual redundancy model turns out to be better than the GSM EFR decoder with standard error concealment procedure. The performance of the channel decoder using residual redundancy is strongly dependent of the index assignment used by the quantifier
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Habrard, Florian. "Élaboration de dispositifs et matériaux mixtes à base de polymères conjugués électroluminescents." Phd thesis, Université Joseph Fourier (Grenoble), 2006. http://tel.archives-ouvertes.fr/tel-00130247.
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Le sujet de cette thèse se situe dans le contexte de l'électronique organique à base de polymères conjugués. Nous avons choisi la famille des polyfluorènes principalement en raison de leur émission dans le bleu, leur bon rendement quantique ainsi que pour la facilité avec laquelle on peut modifier leurs propriétés en greffant différents groupements fonctionnels sur la structure de base du fluorène. L'originalité des recherches effectuées au laboratoire concerne la structure des dispositifs électroluminescents (cellules électrochimiques électroluminescentes ou OLEC) que nous réalisons. Leur principe de fonctionnement repose sur l'utilisation de liquides ioniques ajoutés directement au polymère conjugué sans l'intervention d'un polymère conducteur ionique. Le travail réalisé au cours de cette thèse a principalement consisté à tenter d'améliorer les performances du polyfluorène par l'utilisation de groupements fonctionnels permettant d'augmenter la compatibilité polymère / liquide ionique. Dans cette optique, nous avons mis en œuvre l'utilisation d'un outil de caractérisation particulièrement adapté à nos échantillons : la microscopie à force atomique en mode EFM ou KFM. Cela nous a permis de visualiser précisément la séparation de phase entre le polymère et le liquide ionique. Nous avons ainsi pu montrer que le courant dans un dispositif était grossièrement proportionnel à l'interface polymère / liquide ionique. Nous avons alors proposé une hypothèse expliquant le mode de vieillissement des OLEC. L'amélioration du mélange, c'est-à-dire la maximisation de l'interface polymère / liquide ionique devrait ainsi permettre d'améliorer la durée de vie des dispositifs. L'utilisation de groupements PEO et cyano greffés sur le polyfluorène semble une voie à explorer. Enfin, nous avons décrit le comportement particulier du mélange polyfluorène cyano – THA-TFSI dont la morphologie évolue suivant les conditions de température et de pression.
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Notari, Airton Carlos. "Estudo de incorporações de impurezas doadoras em estruturas semicondutoras III-V crescidas por epitaxia por feixes moleculares." Universidade de São Paulo, 1993. http://www.teses.usp.br/teses/disponiveis/54/54132/tde-09032009-150110/.
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Amostras de Semicondutores III-V foram crescidas usando a técnica de Epitaxia por feixes Moleculares. As propriedades elétricas das estruturas de GaAs com dopagem planar com Silício foram investigadas, e também a saturação e a difusão do Silício nestas amostras. As propriedades ópticas e elétricas das estruturas dopadas planarmente com Selênio foram analisadas, usando as técnicas de Capacitância-voltagem e a de Tunelamento resonante. As propriedades elétricas dos poços quânticos a base de InGaAs/GaAs foram investigadas, em função da posição da impureza planarmente dopada com Silício.III-V semiconductor samples were grown using the Molecular beam epitaxy technique, the electrical properties of the GaAs structures planar doped with silicon were investigated as well as the Silicon saturation and diffusion in these samles. The optcal and electrical properties of structures planar doped with Selenium were analyzed using the Capacitance Voltage and resonant Tunneling techniques. The electrical properties of InGaAs/ GaAs based quantum wells were investigated as a function of the planar doped with Silicon impurity position.
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Li, Wei. "Investigation of Pseudo-Passive Layer Formation in CO2 Corrosion." Ohio University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1307119897.
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Keeler, Farrah Dawn. "Developing an Electronic Film Review for October Sky." Diss., CLICK HERE for online access, 2005. http://contentdm.lib.byu.edu/ETD/image/etd800.pdf.
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Larsson, Rasmus, and Edvard Wikström. "Analysis and implementation of a call simulator for Mobile@Home at Ericsson AB." Thesis, Linköping University, Department of Electrical Engineering, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-2629.
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Mobile telephony technology like GSM made portable telephony a possibility. The arising and development of the Internet made a revolutionary change to communication and interchange of information. Bluetooth wireless technology revolutionizes personal connectivity by providing freedom from wired connections. Combining these technologies together brings the concept of Mobile@Home of Ericsson.
Mobile@Home is a fixed-mobile convergence concept using the fixed network to carry present and future mobile services (e.g. voice, video, mail and Internet access) all the way to the home or office. By combining the high bandwidth of the fixed access network with the wireless technology of Bluetooth, Mobile@Home makes it possible to deliver high bandwidth to the mobile phone. Mobile@Home requires a Bluetooth enabled mobile phone and a Bluetooth enabled HBS (Home Base Station), placed at the home or office. By means of fast IP access (ADSL, cable modem etc.) the HBS connects into the standard mobile core network through a HBSC (Home Base Station Controller).
The purpose of this thesis is the generation of simulated traffic between the HBS and HBSC and to analyze its behavior. This primary involves generation of signaling through an internal protocol, provided by Ericsson, for management and call control, and generation of GSM EFR (Enhanced Full Rate) voice streams over the RTP (Real Time Protocol) protocol. The simulation will consist of both the HBS and MS (Mobile Station). A set of HBS: s with attached MS will call one another through the HBSC. In this assignment only the GSM signaling will be considered because of time and scope limitations. The goal is to validate the RTP traffic generated towards the HBSC. Parameters like packet loss, packet delay and erroneous packets will be analyzed.
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Chevtchenko, Serguei Aleksandrovich. "DEFECTS IN GaN: AN EXPERIMENTAL STUDY." VCU Scholars Compass, 2007. http://scholarscompass.vcu.edu/etd_retro/72.
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This work examines extended, point, and surface defects in GaN by means of electric force microscopy, photoluminescence and deep-level transient spectroscopy. Modeling of the surface band bending, its origin, and the effects of fabrication processing steps are discussed in the first part of the dissertation. Experimental results indicate that spontaneous polarization does not play a predominant role in GaN band bending. An increase of surface band bending due to annealing and etching was observed, while passivation did not produce changes. However, passivation did reduce reverse-bias leakage current by one to two orders of magnitude in GaN Schottky diodes. The optical properties of GaN were found to be sensitive to fabrication processing steps, most likely due to changes in the total density of surface states.The second part of this dissertation concerns the reduction of extended defects and associated deep levels in layers of GaN grown on different templates. Templates employing a low temperature GaN nucleation layer, epitaxial lateral overgrowth, and SiNx nanonetwork are compared in terms of deep level concentrations in the resulting GaN films. The concentrations of two types of traps, A (Ec-ET ~ 0.54-0.58 eV) and B (Ec-ET ~ 0.20-0.24 eV), were the highest for the sample with a low temperature nucleation layer and lowest for a sample with a 6 min SiNx deposition time. We surmise that the defects responsible for the dominant trap A are located along dislocation lines and form clusters.In the last part we investigate the piezoelectric and ferroelectric properties of PZT in Pb(Zr, Ti)O3(PZT)/GaN structures, and the effects of interface states. Sol-gel derived thin PZT films on GaN and Pt/Ti/SiO2/Si surfaces were studied by piezoresponse force microscopy (PFM), where quantitative characterization of piezoelectric properties of PZT films was performed. Superior piezoelectric properties of PZT/GaN/sapphire structures as compared to PZT/ Pt/Ti/SiO2/Si structures were observed and explained by a different preferred orientation of PZT. Despite the possible existence of a strong depolarization field at the PZT/GaN interface, we confirm with PFM the presence of a remanent polarization in PZT/GaN/sapphire structures.
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Imran, Saeed Sohail. "Investigation of Mechanisms for Spur Generation in Fractional-N Frequency Synthesizers." Thesis, Linköpings universitet, Elektroniksystem, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-80886.
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With the advances in wireless communication technology over last two decades, the use of fractional-N frequency synthesizers has increased widely in modern wireless communication applications due to their high frequency resolution and fast settling time. The performance of a fractional-N frequency synthesizer is degraded due to the presence of unwanted spurious tones (spurs) in the output spectrum. The Digital Delta-Sigma Modulator can be directly responsible for the generation of spur because of its inherent nonlinearity and periodicity. Many deterministic and stochastic techniques associated with the architecture of the DDSM have been developed to remove the principal causes responsible for production of spurs. The nonlinearities in a frequency synthesizer are another source for the generation of spurs. In this thesis we have predicted that specific nonlinearities in a fractional-N frequency synthesizer produce spurs at well-defined frequencies even if the output of the DDSM is spur-free. Different spur free DDSM architectures have been investigated for the analysis of spurious tones in the output spectrum of fractional-N frequencysynthesizers. The thesis presents simulation and experimental investigation of mechanisms for spur generation in a fractional-N frequency synthesizer. Simulations are carried out using the CppSim system simulator, MATLAB and Simulink while the experiments are performed on an Analog Devices ADF7021, a high performance narrow-band transceiver IC.
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Rocque, Ryan K. "A Study of the Effectiveness of Annotations in Improving the Listening Comprehension of Intermediate ESL Learners." Diss., CLICK HERE for online access, 2008. http://contentdm.lib.byu.edu/ETD/image/etd2370.pdf.
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Murteira, Martinho José Badagola. "Caracterização da qualidade da água para rega nas captações do sistema Alqueva-Pedrogão." Master's thesis, Universidade de Évora, 2009. http://hdl.handle.net/10174/18527.
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O Empreendimento de Fins Múltiplos de Alqueva (EFMA) é um projecto estruturante centrado na barragem do Alqueva, que pretende garantir o recurso Água na região e com isso viabilizar uma série de infra-estruturas que contribuirão para o desenvolvimento, em termos económicos e sociais, de uma das regiões mais desfavorecidas da Europa. O EFMA é constituído pelo "Reservatório Mãe" e por um conjunto de outras albufeiras de menor dimensão, interligados por uma rede com cerca de dois mil quilómetros de canais e condutas e mais de meia centena de estações de bombagem, contemplando os seguintes usos da água: - Abastecimento público. - Fornecimento de água para o desenvolvimento de actividades agrícolas e agro-industriais; - Produção de energia; Este trabalho tem por objectivo avaliar a adequabilidade da qualidade da água para o uso rega na origem e produzir informação adequada de suporte à decisão. Os resultados obtidos permitem afirmar que de um modo geral a qualidade da água captada no sistema Alqueva- Pedrógão é adequada para o uso rega, apesar de se verificar uma persistente contaminação de coliformes fecais. ABSTRACT; The Multipurpose Alqueva Project (EFMA- Empreendimento de Fins Múltiplos de Alqueva) is a groundwork project centred in Alqueva dam and its reservoir, which intends to guarantee a strategic water reserve in the region, and therefore making possible a series of associated infrastructures, contributing for the potential development of the region, in economic and social terms, in one of the most poorest regions of Europe. The EFMA includes a "Main Reservoir" and set of other dams with lesser dimension, connected by a several canals and pipelines about two thousand kilometers long (including Primary and Secondary Network), and about 50 pumping stations, with the goal of attaining the following main objectives: - Water supply for the development of agricultural and agro-industrial activities; - Production of energy; - Public Water Supply. This study intends to evaluate the suitability of water quality in the origin for irrigation use and to achieve adequate information for support decision. The results have revealed that the quality of water abstracted in the Alqueva - Pedrógão System is suitable for irrigation, although the persistent contamination of fecal coliforms.
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Bringer, Olivier. "Mesures des sections efficaces de capture et potentielsd’incinération des actinides mineurs dans les hauts flux de neutrons : impact sur la transmutation des déchets." Grenoble INPG, 2007. http://www.theses.fr/2007INPG0109.
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Cette thèse se fonde sur l'étude de la transmutation nucléaire des actinides mineurs, En premier lieu, afin de mettre en lumière les paramètres nucléaires apportant le plus d'indétermination sur ce processus, une étude d'impact des incertitudes de l'ensemble des paramètres nucléaires a été réalisée dans le cas de l'incinération de 1,24/Am et du 237Np et dans trois spectres distincts: EFR (rapide), GT-MHR (épithermique) et HI-HWR (thermique). Ainsi, une partie des paramètres mis en valeurs ont pu être mesurés grâce à des campagnes expérimentales dans lesflux de neutrons intenses hautement modérés du réacteur de l'institut Laue-Langevin (Grenoble). Cel/es-ci ont notamment portées sur l'étude de l'incinération et la transmutation de l'américium-24l, du curium-244 et du californium-249. Aufinal, plus de 12 paramètres nucléaires ont pu être déterminés de cette manière au point d'énergie thermiqueThis thesis is based on the study of nuclear transmutation of minor actinides, Rrstly, in order to highlight the nuclear parameters which bring the highest Indetermination on this process, an impact study was proceed over the whole nuclear parameters incertitude on the 241 Am and 237 Np Incineration in three distinct spectra : EFR (fast), GT-MHR (epithermal) and HI-HWR (thermal). Thus, a part of the parameters which were under/ined were measured thanks to different experimental campaigns in the high/y moderated intensive neutron fluxes that are presents in Laue-Langevin institute (Grenoble) reactor. These ones were notably focused on the nuclear Incineration and transmutation of americium-241, curium-244 and californium-249. Rnally, more than 12 parameters were successfully determined in this manner at thermal energy point
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Cook, Mandy Lee Hill. "Behavioral and auditory evoked potential (AEP) hearing measurements in odontocete cetaceans." [Tampa, Fla] : University of South Florida, 2006. http://purl.fcla.edu/usf/dc/et/SFE0001769.
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Bica, Manuel Francisco Pinela Aires da. "Barragem do Pisão - análise dos aspectos condicionantes na sua construção." Master's thesis, Universidade de Évora, 2010. http://hdl.handle.net/10174/20859.
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O presente trabalho descreve as principais características da barragem do Pisão e aborda as principais alterações efectuadas durante a empreitada de construção. Descreve os materiais utilizados na construção, caracteriza a fundação, bem como, a metodologia adoptada para a realização do aterro experimental da barragem. Simultaneamente procura identificar e caracterizar alguns dos principais problemas que foram detectados na concepção e construção e que, como tal, condicionam a sua execução. Por fim, apresenta-se paralelamente algumas sugestões, que sirvam de orientação para futuros projectos a implementar de idêntica natureza. – ÁBSTRACT: This study aim to describe the most relevant characteristics of Pisão dam at the sarne time it focus upon the main changes undertaken during the construction works. Construction materials description, foundation characterization and work method used during construction of the dam landfill, are presented. Furthermore, the study seeks to identify and characterize the main constraints that have limited the project execution during the dam conception and construction. Finally, some suggestions that may be used as major guidelines in similar projects, are also presented.
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SILVA, JÚNIOR João Ferreira da. "Um Algoritmo para Distribuição Balanceada de Carga Elétrica e Redução de Consumo de Energia em Centros de Dados e Nuvens." Universidade Federal de Pernambuco, 2013. https://repositorio.ufpe.br/handle/123456789/12376.
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Os avanços tecnológicos acontecem por intermédio de pesquisas e estudos, inclusive com a criação de novos paradigmas, tais como a computação em nuvem, comércio eletrônico e redes sociais. Em alguns casos, grandes centros de dados são utilizados para suportar esses paradigmas. Com isso, estes grandes centros de dados tornaram-se elementos críticos no desenvolvimento de tarefas diárias, o que sugere que, a cada dia, utilizamos mais seus recursos, aumentando a demanda e, consequentemente, o consumo elétrico. Hodiernamente, o consumo de energia é uma questão de interesse comum. Pesquisas demonstram que, como consequência da constante evolução e expansão da tecnologia da informação, os centros de dados e as nuvens (cloud computing) são grandes consumidores de energia elétrica. Com esse alto consumo, destacam-se as questões de sustentabilidade e custo. Neste contexto, a presente dissertação propõe um algoritmo de distribuição de carga elétrica (ADCE) para otimizar a distribuição de energia em infraestruturas elétricas de centros de dados e nuvens privadas. O ADCE é suportado pelo ambiente denominado Mercury, que é capaz de realizar uma avaliação integrada das métricas de confiabilidade, custo e sustentabilidade. O ADCE otimiza, mais especificamente, a distribuição da corrente elétrica na modelagem de fluxo de energia (EFM - Energy Flow Model). A modelagem em EFM é responsável por estimar as questões de sustentabilidade e de custo das infraestruturas elétricas de centros de dados e nuvens, respeitando as restrições de capacidade de energia que cada dispositivo é capaz de fornecer (considerando o sistema elétrico) ou extrair (considerando o sistema de refrigeração). Ademais, dois estudos de caso são apresentados, onde são analisadas sete infraestruturas elétricas de um centro de dados e seis de uma nuvem privada. Para os centros de dados foi alcançada uma redução no consumo de energia de até 15,5% e a métrica utilizada para avaliar a redução do impacto ambiental (exergia) foi reduzida em mais da metade de seu valor. No que concerne ao estudo das nuvens privadas a redução do consumo de energia foi de até 9,7% e da exergia de para quase um terço de seu valor inicial. Os resultados obtidos foram significativos, uma vez que as preocupações ambientais ganham destaque com o passar dos anos e os recursos financeiros das empresas são finitos e muito valiosos.
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Thorell, Hampus. "Voice Activity Detection in the Tiger Platform." Thesis, Linköping University, Department of Electrical Engineering, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-6586.
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Sectra Communications AB has developed a terminal for encrypted communication called the Tiger platform. During voice communication delays have sometimes been experienced resulting in conversational complications.
A solution to this problem, as was proposed by Sectra, would be to introduce voice activity detection, which means a separation of speech parts and non-speech parts of the input signal, to the Tiger platform. By only transferring the speech parts to the receiver, the bandwidth needed should be dramatically decreased. A lower bandwidth needed implies that the delays slowly should disappear. The problem is then to come up with a method that manages to distinguish the speech parts from the input signal. Fortunately a lot of theory on the subject has been done and numerous voice activity methods exist today.
In this thesis the theory of voice activity detection has been studied. A review of voice activity detectors that exist on the market today followed by an evaluation of some of these was performed in order to select a suitable candidate for the Tiger platform. This evaluation would later become the foundation for the selection of a voice activity detector for implementation.
Finally, the implementation of the chosen voice activity detector, including a comfort noise generator, was done on the platform. This implementation was based on the special requirements of the platform. Tests of the implementation in office environments show that possible delays are steadily being reduced during periods of speech inactivity, while the active speech quality is preserved.
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Tomasi-Gustafsson, Egle. "Étude des réactions de stripping d'un nucléon induites par ions lourds aux énergies de quelques dizaines de MeV par nucléon." Paris 11, 1988. http://www.theses.fr/1988PA112144.
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Nous avons étudié le peuplement des états discrets par réactions de stripping d'un nucléon sur une cible de ²⁰⁸Pb, induites par le faisceau de 480 MeV de ¹ ² C fourni par le laboratoire national GANIL à Caen. Nous avons mesuré les spectres en énergie des éjectiles avec une résolution en énergie de 200 keV de largeur à mi-hauteur à l'aide du spectromètre magnétique à perte d'énergie SPEG. Nous avons analysé les niveaux discrets, présents jusqu'à 6 MeV d'énergie d'excitation et de larges structures présentes à 9-10 MeV. La comparaison avec des résultats obtenus avec un faisceau de 160 à 793 MeV où 1e nucléon transféré se trouve dans une configuration initiale différente que dans le cas du ¹ ² C, a montré que le peuplement des états discrets aux énergies incidentes de quelques dizaines de MeV par nucléon est gouverné par deux règles de sélection : 1) Les niveaux les plus peuplés correspondent à des états de grand moment angulaire car les moments angulaires pour les ondes rasantes d'entrée et de sortie diffèrent de plusieurs unités. 2) Les niveaux les plus peuplés correspondent aux transitions qui se font sans retournement du spin : le nucléon transféré tourne dans le même sens autour des cœurs des noyaux avant et après le transfert. Ce comportement est opposé à ce qui se passe à basse énergie. Ces règles sont bien comprises dans le cadre du modèle semi-classique de D. M. Brink (1972) et implicitement contenues dans les calculs suivant l'approximation de Born en ondes distordues en portée finie (EFR-DWBA). L'analyse EFR-DWBA reproduit très bien les sections efficaces différentielles aussi bien en forme qu'en valeur absolue pour le système ¹ ² C + ²⁰⁸Pb à 480 MeV. Cela nous a permis d'extraire les facteurs spectroscopiques qui sont en bon accord avec ceux qui sont connus théoriquement ou extraits expérimentalement à plus basse énergie ou encore avec des projectiles plus légers. Nous avons étudié en détail l'influence des différents paramètres qui rentrent dans le calcul des sections efficaces. Les noyaux éjectiles ayant un spin, nous avons aussi fait des calculs en introduisant un terme de spin-orbite dans le potentiel optique de la voie de sortie. Nous avons de plus observé les composants de la fragmentation d'états de particule indépendante de haut spin à haute énergie d'excitation qui sont favorisés par les deux règles de sélection. Les facteurs spectroscopiques correspondants sont en accord avec des expériences de stripping d'un nucléonWe have studied at the GANIL facility (Caen) the one-nucleon stripping reactions (¹ ² C,¹ ¹ C) and (¹ ² C,¹ ¹ B) on a ²⁰⁸Pb target at an incident energy of 480MeV. We have analysed the energy spectra up to 15 MeV excitation energy. The energy resolution obtained with the energy loss magnetic spectrometer SPEG was 200 keV FWHM. The comparison with similar reactions induced by 160 on ²⁰⁸Pb at 793 MeV gives experimental evidence of the population of the excited discrete levels in terms of two selection rules : 1) High spin states are selected ; 2) the most populated states correspond to no spin-flip transitions. These rules are well understood in the semi-classical model of D. M. Brink, and are contained in the Exact Finite Range-Distorted Wave Born Approximation (EFR-DWBA) formalism. The angular distributions of the observed states were measured between 2° and 9° in the laboratory system. The EFR-DWBA calculations reproduce fairly well their shape, allowing us to extract spectroscopic factors in agreement with those previously known. EFR-DWBA calculations for ¹ ² C induced reactions reproduce also the absolute values of the cross sections for all the analysed states, while for the reaction induced by l6O the theory overestimates the experimental values by a factor of five to ten. A detailed study of the influence of the various parameters was carried out: the optical model parameters extracted from elastic scattering, which was also measured, and the form factor parameters, which were taken from previous studies at lower incident energy for the same system. The EFR-DWBA absolute cross sections are found to be very sensitive to the optical potential reduced radius, which, on the other hand, doesn't affect much the shape of the transfer reaction angular distributions. Moreover, between 4 and 10 MeV excitation energy, broad peaks and large structures have been observed, which are attributed to the excitation of high spin states which are fragmented into many components. We have looked at the effect of a spin-orbit term in heavy ion reactions at high energy. Polarization measurements are necessary to determine without ambiguities if this term does or does not play an important role, as we might expect from the fact that the angular momenta involved in the reactions investigated here are very large
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Lin, Y. J., and 林揚展. "The weighting function and base functionof EFM." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/17973084109774270426.
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碩士國立中央大學
土木工程研究所
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The weighting function and base function of EFM ABSTRACT Keywords：element free，weighting function，base function，moving least square In this thesis,treatment of the interpolated function including the weighting and base functions in the element free method is studied in detail. The element free method(EFM) is a newly proposed numerical method in applied mechanics. This method is formulated by a technique so called “ moving least square”(MLS) to interpolate the discrete data within the domain to be analysed. Both the weighting and base functions influence the interpolated function which controls the accuracy of solving solid mechanics problems. After introducing many kinds of weighting function,the cantliver beam problems have been solved with EFM in diffrent kind weighting function and different base function. Numerical examples illustrate that some kinds of weighting function will get better solutions than others. After all,the rule of the choice of the weighting function has been presented. Numerical examples illustrate that the 2 order base function will get better solutions than the 1order base function in some problems.