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Sandqvist, Mattias, and Robert Johansson. "Implementation av Network Admission Control." Thesis, Jönköping University, JTH, Computer and Electrical Engineering, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-901.
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This examination work is about implementation of Cisco Systems Network Admission Control (NAC) within a leading IT-company in region of Jönköping. NAC is a technique that is used for securing the internal network from the inside. NAC can verify that the client who connects to the network has the latest antivirus updates and latest operative system hotfixes. Clients who don’t meet the criteria can be placed in quarantine VLAN where they only have access to the update servers. There are also functions that handle VLAN assignment for users.
The assignment where to produce a solution for an implementation of NAC in the company’s computer network. The questions that where asked are the following, if and how could NAC be implemented in the company’s computer network.
An analysis where made of the company’s computer network, to see if the computer network meet the requirements for implementing NAC. The result of this analysis showed that there where a loss of functions needed for a working NAC solution. The computer network where rebuild from scratch to meet the new demands for NAC. After completion of the new computer network the NAC solution were taking shape. This was made in consultation with the company to get a clear picture of the needs. The result of the discussion lead to a so called “Out-of-band virtual gateway” solution. The solution builds on that the client is placed in an authentication VLAN when connecting to the computer network, after that an authentication process begins. During this process the client is checked to verify that the criteria’s are fulfilled, if so the client is moved to his access VLAN.
These solutions increase the internal security in the computer network and reduce the risks for virus spreading within the network.
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Wende, Sandra, Sonja Bonin, Oskar Götze, Heike Betat, and Mario Mörl. "The identity of the discriminator base has an impact on CCA addition." Universitätsbibliothek Leipzig, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-172120.
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CCA-adding enzymes synthesize and maintain the C-C-A sequence at the tRNA 3'-end, generating the attachment site for amino acids. While tRNAs are the most prominent substrates for this polymerase, CCA
additions on non-tRNA transcripts are described as well. To identify general features for substrate requirement, a pool of randomized transcripts was incubated with the human CCA-adding enzyme. Most
of the RNAs accepted for CCA addition carry an acceptor stem-like terminal structure, consistent with tRNA as the main substrate group for this enzyme. While these RNAs show no sequence conservation,
the position upstream of the CCA end was in most cases represented by an adenosine residue. In tRNA, this position is described as discriminator base, an important identity element for correct aminoacylation. Mutational analysis of the impact of the discriminator
identity on CCA addition revealed that purine bases (with a preference for adenosine) are strongly favoured over pyrimidines. Furthermore, depending on the tRNA context, a cytosine discriminator can
cause a dramatic number of misincorporations during CCA addition. The data correlate with a high frequency of adenosine residues at the discriminator position observed in vivo. Originally identified as a
prominent identity element for aminoacylation, this position represents a likewise important element for efficient and accurate CCA addition.
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Mattatall, Neil R. "Cytochrome aa¦3, cytochrome caa¦3, and YpmQ of Bacillus subtilis." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/NQ56090.pdf.
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Rocha, Adilson Pereira da. "Estudo da aderência no reparo com concreto autoadensável (CAA): influência do preparo da superfície, da resistência à compressão do concreto da base e do tipo do concreto (convencional e CAA)." Universidade Federal de Goiás, 2011. http://repositorio.bc.ufg.br/tede/handle/tede/4190.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
Efficient repairs in concrete structures require perfect bonding between the base concrete and the applied concrete. The experimental analysis shown in this study focused on how bonding is influenced by three types of base concrete preparation: hydro-jet blasting (BHD), manual scabbling (BMA) and mechanical scabbling (BME), as well as two types of base surface condition: dry (0%) and humid (100%) and also by the application of three different types of bonding agents: B - cement + water; C – cement + water + additive superplasticizer; D – cement + water + additive superplasticizer + active sílica. Fifteen conventional concrete bases prepared using concrete with compressive strength of class C20 and fifteen self-consolidating concrete bases with compressive strength of class C30 were tested. Surface roughness was characterized using profiles according to parameters Ra (standard deviation with respect to an average line) and Rz (average height between consecutives peaks and valleys). Self-consolidating concrete with C40 compressive strength was used to repair the concrete bases. Dyna Proceq apparatus was used to determine tension bonding strength. The hydro-jet blasting (BHD) preparation presented the lowest surface roughness values and the highest bonding strength results as well as the lowest values of the coefficient of variation. The manual scabbling (BMA) preparation presented intermediary results. The mechanical scabbling (BME) preparation presented the highest surface roughness values and the lowest bonding strength results. Surface humidity increase the number of concrete base ruptures. The use of bonding agents increased bonding strength regardless of the degree of surface humidity.
A busca pela execução eficiente de um reparo em estruturas de concreto passa pela procura de uma aderência perfeita entre o concreto aplicado e o substrato. Durante a análise experimental, realizada nesta dissertação, analisou-se a influência de três tipos de preparo dos substratos – preparo com hidrojateadora (BHD), apicoamento manual (BMA) e apicoamento mecânico (BME), duas condições de superfície: seca (0%) e úmida (100%) e da aplicação de três tipos de ponte de aderência: B – cimento + água; C – cimento + água + aditivo superplastificante e D – cimento + água + aditivo superplastificante + sílica ativa, no sistema de aderência. Para a representação do substrato foram confeccionadas quinze bases de concreto convencional CCV de classe C20 e quinze de concreto autoadensável CAA de classe C30. A rugosidade foi caracterizada através dos perfis, de acordo com os parâmetros Ra (desvio padrão em relação à linha média) e Rz (altura média entre o pico e o vale consecutivo). Para concretagem do reparo utilizou-se o concreto autoadensável CAA de classe C40. O aparelho Dyna Proceq foi utilizado para as determinações de resistência de aderência à tração. O preparo com hidrojateadora (BHD) apresentou os menores valores de rugosidade e os maiores resultados de resistência de aderência, além de menores valores de coeficientes de variação. O preparo por apicoamento manual (BMA) apresentou resultados intermediários. O preparo por apicoamento mecânico (BME) apresentou os maiores valores de rugosidade e os menores resultados de resistência de aderência. O umedecimento da superfície promoveu um maior número de rupturas no substrato. O uso de pontes de aderência contribuiu para o aumento da resistência de aderência independentemente da condição de umidade da superfície.
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Aflalo, Bernardo Santos. "CFD and CAA analysis of single stream isothermal jets with noise suppression devices." Instituto Tecnológico de Aeronáutica, 2009. http://www.bd.bibl.ita.br/tde_busca/arquivo.php?codArquivo=1210.
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Since the 50's, with the appearance of the turbojet engines, the jet noise is being exhaustively studied, because it is one of the most important source of aircraft noise. Many attempts have been made to reduce the jet noise, including higher by-pass turbofan engines. Chevron nozzles also have been used by the industry to try to reduce the jet noise with a low performance and weight penalty. This work shows a computation procedure to assess how this noise suppression devices impact on both fluid dynamics and acoustics of single isothermal jets. Towards this goal, different chevron nozzles, with 6, 8 and 12 lobes have been analyzed. The calculation procedure is based on a Reynolds Average Navier-Stokes calculation, followed by a stochastic noise generation and radiation method, resulting in a relatively fast noise calculation procedure. The simulations have been carried out using the commercial software CFD++. The calculation procedure has predicted the expected fluid dynamic and acoustic behavior for chevron nozzles, e.g., shortening the potential core length, high frequency noise increase and low frequency noise attenuation. The parametric study of the number of lobes has shown that this parameter impacts the mixing region. Moreover, varying this parameter is a way to attain different low frequency reductions, without great impacts on the highest frequencies. Although the procedure did not capture correctly the absolute values of the acoustic response, the results show that this relatively simple and quick analysis reproduced important parameters in designing new nozzles and can be used as a way to better understand the influence of chevrons.
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Durand, Christopher. "Validation of a CAA Code for a Case of Vortical Gust-Stator Interaction." University of Toledo / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1481203960382465.
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Selvaraj, Sudharshan. "Use of CFD to Validate and Predict the Jet Noise from a High Aspect-ratio Nozzle at Off-design Conditions." University of Cincinnati / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1595850094240426.
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Cunha, Guilherme. "Optimisation d'une méthodologie de simulation numérique pour l'aéroacoustique basée sur un couplage faible des méthodes d'aérodynamique instationnaire et de propagation acoustique." Thesis, Toulouse, ISAE, 2012. http://www.theses.fr/2012ESAE0028/document.
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Le présent travail a consisté à évaluer, améliorer et valider plus avant une méthode de couplage faible CFD/CAA, notamment relativement à son application à des problèmes réalistes de bruit avion. Entre autres choses, il a été ici montré dans quelle mesure une telle méthode hybride peut effectivement (i) s’accommoder des contraintes inhérentes aux applications réalistes, (ii) sans être menacée par certains de ses inévitables effets de bord (tels que la dégradation du signal auxquelles sont soumises les données CFD, lorsqu’elles sont traitées ou exploitées acoustiquement)The present work consisted in improving, assessing and validating further the CFD/CAA surface weak coupling methodology, with respect to its application to realistic problems of aircraft noise. In particular, it was here shown how far such hybrid methodology could (i) cope with all stringent constraints that are dictated by real-life applications, (ii) without being jeopardized by some of the unavoidable side-effects (such as the signal degradation to which CFD data are subjected, when processed or being then acoustically exploited)
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Gill, Mundeep. "Development and evaluation of CAA as a formative assessment tool for university- level mehanics." Thesis, Brunel University, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.488685.
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Computer-Aided Assessments (CAA) are increasingly being used in Higher Education as a formative assessment tool. A major function is to provide students with instantaneous feedback, so that they can learn from mistakes and develop their skills. It is therefore essential to understand and identify the level of feedback students can and do engage with, and what they are able to learn from it. This thesis aims to identify the benefits of incorporating CAA into a course to provide formative feedback and evaluate its efficacy.
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Luvizotto, Danice Mazzer. "Caracterização fisiológica e molecular de Burkholderia spp. associadas às raízes de caa-de-açúcar." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/11/11138/tde-15122008-144208/.
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A cana-de-açúcar (Saccharum sp.) é uma planta que ocupa posição de destaque entre as culturas de importância econômica no cenário internacional, principalmente no Brasil, que é o maior produtor mundial. O estudo da diversidade microbiana associada a plantas, principalmente aquelas com interesse comercial, apresenta-se como importante alternativa para melhorar as características e a sustentabilidade destas culturas. Neste sentido, bactérias endofíticas e rizobactérias tem sido alvo de muitos estudos, pois apresentam efeitos benéficos para as plantas, como promoção de crescimento e inibição de patógenos. Um dos grupos de bactérias que colonizam a cana-de-açúcar é composto por espécies do gênero Burkholderia. Este gênero é composto de bactérias que podem ser encontradas em diferentes nichos ecológicos, como o solo, a água, ou em associação com plantas, fungos, e outros animais, além de humanos. Na interação bactéria-planta, as espécies de Burkholderia podem colonizar a rizosfera e o interior das raízes hospedeiro, onde podem estimular o crescimento do vegetal, contribuir para sua nutrição, como também protegê-lo da ação de fitopatógenos. Sendo assim, isolados de Burkholderia spp. do interior das raízes (endofíticos) e da rizosfera de cana-de-açúcar foram avaliados quanto à capacidade de fixar nitrogênio, produzir AIA, sideróforos, enzimas de interesse biotecnológico, solubilizar fosfato inorgânico e inibir patógenos desta cultura. Estes isolados também foram caracterizados geneticamente por análise de restrição e seqüenciamento dos genes 16S rDNA e gyrB, além da caracterização genotípica por BOX-PCR. Os resultados indicam que os isolados possuem potencial para promoção de crescimento vegetal, inibição de patógenos e produção de lipases. Filogeneticamente, a maioria dos isolados pertencem ao complexo Burkholderia cepacia com similaridade à B. cepacia e B. cenocepacia. Considerando a ocorrência dos isolados como endófitos ou rizosféricos, as metodologias fenotípicas e genotípicas não foram capazes de distinguir os membros componentes destas comunidades. Este trabalho evidencia a ampla associação deste grupo com cana-de-açúcar, e destaca as possíveis aplicações que tais bactérias podem ter no cultivo e sustentabilidade desta cultura.Sugarcane (Saccharum spp.) occupies a position of prominence among the economically important crops in the international scene, mainly in Brazil, which is the world\'s largest producer. The study of microbial diversity associated with plants, especially those with commercial interest, presents itself an important alternative to improve the performance and sustainability of these crops. In this sense, endophytic bacteria and rhizobacteria has been target of many studies, since they have beneficial effects for plants, such as plant growth promotion and inhibition of pathogens. One of the bacterial groups that colonize sugarcane is composed of species of the genus Burkholderia. This genus is composed of a bacterium that can be found in different ecological niches, such as soil, water, or in association with plants, fungi and other animals, as well as in humans. In the association bacterium-plant, the species of Burkholderia can colonize the rhizosphere and the inside of the host roots, which can stimulate the growth of the plant, contributing to its nutrition, but also protects it from the action of phytopathogens. Thus strains of Burkholderia spp. isolated from the inside of the roots (endophytic) and from the rhizosphere of sugarcane were evaluated for the ability to fix nitrogen, produce IAA, siderophores, enzymes of biotechnological interests, solubilize inorganic phosphate and inhibits pathogens of the same crop. These strains were also genetically characterized by the analysis of enzymatic restriction and sequencing of 16S rDNA and gyrB genes, in addition to the characterization by genotypic technique BOX-PCR. The results indicate that the strains have potential for plant growth promotion, inhibition of pathogens and production of lipases. Phylogenetically, the isolates were affiliated to Burkholderia cepacia complex, with mainly similarity to B. cepacia and B. cenocepacia. Considering the occurrence of isolated as endophytes or rhizosphere, the genotypic and phenotypic methods were not able to distinguish the members of these communities. This research work demonstrates the broad association that this group has with sugarcane, and highlights the possible applications that these bacteria may have in cultivation and sustainability of this crop.
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Hortêncio, Tânia Maria de Oliveira Serra. "Ensaios de fadiga sob condições de fretting com o cabo CAA 397,5 MCM - IBIS." reponame:Repositório Institucional da UnB, 2009. http://repositorio.unb.br/handle/10482/6951.
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Dissertação (mestrado)—Universidade de Brasília, Faculdade de Tecnologia, Departamento de Engenharia Mecânica, 2009.Submitted by Jaqueline Ferreira de Souza (jaquefs.braz@gmail.com) on 2011-02-28T11:27:59Z No. of bitstreams: 1 2009_TaniaMariadeOliveiraSerraHortencio.pdf: 16223040 bytes, checksum: 7ab702a94bb1bed964b9e8298d1026d4 (MD5)
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O presente trabalho é de natureza experimental e, visa apresentar uma contribuição sobre o estudo da estimativa de vida útil de cabos condutores de energia elétrica, tendo como referência a análise da resistência à fadiga por fretting. Em particular, o levantamento de dados preliminares que possibilitem a determinação da curva de durabilidade (Curva de Wöhler ou S-N) da montagem do cabo CAA 397,5 MCM - IBIS, com o grampo de suspensão monoarticulado, assim como, identificar as características associadas ao aspecto e posicionamento das falhas encontradas neste tipo de cabo. Testes a uma mesma amplitude de tensão foram conduzidos, observando-se a ruptura do primeiro, segundo e terceiro fio de alumínio e registrando-se o número de ciclos experimentado pela montagem até o instante de cada quebra. Repetindo-se o teste para diferentes amplitudes de deslocamento pode-se então traçar uma curva da amplitude de tensão contra o número de ciclos, a qual é denominada de Curva S-N ou de Wöhler. Para estabelecer a tensão gerada na região de falha utilizou-se a fórmula de Poffenberger-Swart (1965).Os ensaios foram executados, de acordo com as recomendações da CIGRE (1985), EPRI (1979) e IEEE (1978), em uma bancada de 46,8 metros de comprimento, em ambiente climatizado, com sistema de controle dos equipamentos totalmente informatizado.Para a combinação cabogrampo usada, a Curva Limite de Segurança da CIGRÉ (CSBL) mostrou-se muito conservativa, isto é, a vida do cabo é de 5 a 10 vezes maior quando calculada utilizando a curva específica do material como referência.Através do mapeamento das falhas contatouse que para amplitudes de deslocamento menores que 1,0 mm, de maneira geral as falhas ocorreram na camada externa, já para amplitudes maiores a maior incidência até três falhas, foi na camada interna. O valor médio das distâncias das falhas na camada externa foi de 26,7 mm e na camada interna foi de 26,2 mm. Esta constatação evidencia que a previsão da vida útil em fadiga do cabo é de grande importância para as atividades de manutenção, isto porque, as quebras dos fios ocorrem dentro do grampo de suspensão e, portanto não podem ser identificadas nas inspeções visuais. _______________________________________________________________________________ ABSTRACT
The present wok consists of an experimental research on fretting fatigue of an ACSR IBIS overhead conductor, with the objective to contribute to the study of the estimated fatigue life of such components. More specifically, tests were conducted in the same bending displacement amplitude (peak to peak) at a position on the cable 89 mm away from the last point of contact between cable and the mono-articulated aluminium clamping system. The rupture of the first, second and third aluminum strands were monitored as well as the number of cycles experienced by the assembly until the moment of each break. Repeating the test for different levels of prescribed displacement amplitudes one can then plot a curve of stress amplitude versus fatigue life, the so called S-N or Wöhler`s Curve. To correlate the prescribed displacement with stress amplitude Poffenberger-Swart equation was used. The tests were performed in accordance with the recommendations of CIGRE (1985), EPRI (1979) and IEE (1978), in a 46.8 meters long span, in air conditioned environment and using a closed loop control system to assure the repeatability of the tests. The results of the tests showed that, for the conductor/clamp mounting used, the CIGRE Safe Border Line (CSBL) curve was extremely conservative. The actual conductor life was 5 to 10 times higher than the value estimated by the CSBL for the same level of stress amplitude. Such result emphasizes the need to raise specific laboratory S-N curves for different cable/clamp assemblies should accuracy of life estimates be pursued. Mapping the wire failures it was found that for displacement amplitudes smaller than 1 mm, the failures generally occurred in the outer layer, while for amplitudes larger than 1 mm, they preferably occurred in the inner aluminium layer, for up to three failures. Such wire breaks were localized inside the clamp at average distances of 26.7 mm in the outer layer and 26.2 mm in the inner layer, both measured from the clamp mouth. The fact that the broken strand occurs well within the suspension clamp means that it can not be identified by visual inspection and that even inspections by infrared thermography may not be effective, demonstrating the need to establish an accurate methodology to estimate the remaining conductor life in order to allow maintenance before a cathastrofic breakage of the whole cable.
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Qian, Jingjing. "A Step Implementation For Product Structure Data Exchange." Thesis, Linköpings universitet, Institutionen för datavetenskap, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-76684.
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Scania is a Swedish automotive manufacturer for heavy vehicles and engines. It also offers transport solutions and long term commitment for customers. In today's Scania, a modular system provides a huge variety of specifications to meet varying dramatic needs for different customers. In order to be able to meet the diverse requirements of customers, modular approach with the support of reusable components is used to increase the efficiency of designing different products. To customize both product development and product design, computer aided design(CAD) is used to support the process of design and design documentation. "CATIA" is a multi-platform CAD software and "ENOVIA" is a product modeling product offers product database management for virtual model design into CATIA, both "CATIA" and "ENOVIA" are developed by the French company Dassault Systemes are chosen by Scania to support its product development. The modular system approach requires the system support for product structure, which is managed by a mainframe called SPECTRA. The thesis project is mainly about system designing a new module which takes the responsibility for exchanging information between SPECTRA and ENOVIA. In more detail, the new component is to perform a mapping of data in SPECTRA format into a format which ENOVIA can import. The mapping module has several interfaces with other applications in the system. JavaMigrator provides the environment to import data from the mainframe and transfer the data into the module and finally output the expected data format into ENOVIA. To achieve this purpose, several possible solutions were proposed and several methods were tried. Since an in-house developed CAA-module is highly preferred by Scania, the new mapping component will finally be designed into two separate modules, the first part converts the XML extracted from SPECTRA into an intermediate format and the second part is designed to convert the intermediate file into the expected target file. The intermediate file is required, since the format is independent of changes in both SPECTRA and ENOVIA. Furthermore, it is flexible and less complex to maintain than direct mapping from exported XML to ENOVIA. The report focuses on five parts, background, project specification, methodology, implementation, result and future work.
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Goh, Jeffrey Mau Seong. "The principles and policies of regulating airline competition." Thesis, University of Sheffield, 1999. http://etheses.whiterose.ac.uk/6030/.
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Regulation in its generic sense has existed for a very long time in different forms, with different aims and different problems of accountability, but the study of competition regulation by a Government agency has perhaps become fashionable only in recent years. This thesis consists of two leading themes. First, it will contend that, whilst the market system has been seriously underestimated as a social institution to the extent that it should be left to operate and organise itself where that is possible, it is at the same time not always self-regulating. Residual intervention by the State or its agencies will remain necessary in strategic cases, either to protect individual autonomy and choice, or to correct failures of the market system. The question is simply more or less regulation. Secondly, and on that premise, competition regulation must be distinguished into economic regulation and antitrust regulation because the relationship between them is inversely proportional: the more intense economic regulation is, the less important antitrust regulation becomes. By implication then, economic liberalisation or deregulation must be accompanied by a robust framework of antitrust regulation to ensure that the conditions of sustainable competition are not threatened by anti-competitive practices. Conditions of sustainable competition are thus critical for market contestability. For many years, domestic and international airline competition has been the subject of comprehensive regulation. With the passage of time, however, the thinking has changed and, no doubt, liberal policies and practices will continue to find expression in future political and economic sentiments. The responsibility for regulating airlines in the United Kingdom falls on the Civil Aviation Authority, which has played a formidable role in transforming the policy of heavy regulation into minimal regulation, although much of that regulatory landscape has now been altered with the advent of the Single European Aviation Market. The experiences of, both, the CAA and the new SEATNI provide an illuminating account of the evolutionary process of regulating airline competition, that from economic to antitrust regulation.
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Sy, Birame. "Adaptabilité en espace d'un schéma volumes finis d'ordre élevé pour la CFD/CAA des turbomachines." Thesis, Paris, HESAM, 2020. http://www.theses.fr/2020HESAE045.
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A l’ère du numérique, le cycle de développement d’un produit se fait dans sa quasi totalité sur ordinateur. Il n’est plus nécessaire de produire physiquement des versions préliminaires. Leurs caractéristiques peuvent être testées avec une précision dépendante de la maturité des méthodes de simulation. Les acteurs de la recherche en simulation numérique ont donc pour défi de transposer leurs récentes avancées vers l’industrie. En mécanique des fluides, les codes de calcul doivent gagner en adaptabilité afin de prendre en compte la morphologie du problème et du maillage. Le paramétrage des méthodes avancées doit pouvoir être délégué par l’utilisateur non-expert à la machine. Ce travail de recherche porte sur l’adaptabilité en espace d’un schéma volumes finis d’ordre élevé (FV-MLS). L’ordre élevé est un élément indispensable afin de capter les phénomènes fortement instationnaires.Pour augmenter l’ordre de précision, le schéma FV-MLS fait intervenir une reconstruction polynomiale d’ordre élevé par Moindres Carrés Mobiles. MLS affiche un fort potentiel en terme de flexibilité pour traiter des géométries complexes. Elle possède par ailleurs un nombre important de paramètres pouvant être intégrés dans un procédé d’optimisation. Ces travaux ont tout d’abord apporté des réponses concernant la sensibilité de la méthode vis-à-vis des paramètres MLS. À un second niveau, une série d’algorithmes de choix pertinent de ces paramètres a été mise au point, tout en améliorant nettement la robustesse, la précision et l’efficacité de calcul. La charge de l’utilisateur a ainsi été réduite de manière conséquente, lui permettant de se recentrer sur son cœur de métier. Cette méthodologie a été validée jusqu’à l’ordre 6. Pour améliorer la robustesse au schéma numérique vis-à-vis de l’anisotropie du maillage, un nouveau cadre de reconstruction locale d’ordre élevée a été défini.Cette reconstruction locale permet de réduire drastiquement les effets de l’anisotropie. Plusieurs cas de validation et exemples d’applications ont été réalisé afin de démonter l’intérêt des méthodes proposéesIn the digital age, almost all of a product’s development cycle is done on a computer. There is no longer a need to physically produce drafts. Their characteristics can be tested with precision that depends on the maturity of the simulation methods. Researchers in digital simulation therefore have the challenge of transferring their recent advances to industry. In fluid mechanics, the computer codes must gain in adaptability in order to take into account the morphology of the problem and the mesh.The configuration of advanced methods should be delegated by the non-expert user to the machine.This research work focused on the adaptability in space of a high order finite volume scheme (FV-MLS). The high order is an essential element in order to capture highly unsteady phenomena. To increase the order of precision, the FV-MLS scheme involves a high order polynomial reconstruction by Least Mobile Squares. MLS has great potential in terms of flexibility for handling complex geometries. It also has a large number of parameters that can be integrated into an optimization process.This work first provided answers concerning the sensitivity of the method regarding the MLS parameters. At a second level, a series of algorithms for the relevant choice of these parameters has been developed, while clearly improving the robustness, the precision and the calculation efficiency. The user’s load has therefore been reduced significantly, allowing him to focus on his core business. This methodology has been validated up to order 6. To improve the robustness of the numerical scheme vis-à-vis the anisotropy of the mesh, a new high-order local reconstruction framework has been defined. This local reconstruction makes it possible to reduce or even annihilate the effects of anisotropy. Several validation cases and examples of applications have been carried out in order to demonstrate the value of the proposed methods
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Thilakaratne, Ruffina S. "Competence-based validation of architectural education : a critical analysis of the CAA validation in Asia /." Thesis, Click to view the E-thesis via HKUTO, 2002. http://sunzi.lib.hku.hk/hkuto/record/B42576829.
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Clair, Vincent. "Calcul numérique de la réponse acoustique d'un aubage soumis à un sillage turbulent." Thesis, Lyon 1, 2013. http://www.theses.fr/2013LYO10296/document.
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Le bruit généré par l'impact du sillage de la soufflante avec les aubes du redresseur est une source prédominante des turboréacteurs en conditions d'approche, et la composante à large bande contribue fortement au niveau sonore global. Une méthode numérique basée sur un code CAA résolvant les équations d Euler est développée dans cette thèse afin d'estimer le bruit d'interaction entre un sillage turbulent et un aubage de géométrie quelconque. Le sillage amont est modélisé à l'aide d'une méthode stochastique supposant un spectre de turbulence homogène isotrope et une représentation spatiale simplifiée du champ de vitesse. Ces fluctuations de vitesse sont injectées dans le code CAA via des conditions aux limites adéquates. La méthode ainsi mise en place est validée dans un premier temps sur des cas d'interaction avec une plaque plane en comparant les résultats numériques aux solutions du modèle d'Amiet. Un chaınage avec une méthode intégrale est aussi réalisé pour estimer le rayonnement acoustique. La méthode numérique est ensuite mise en œuvre pour simuler la réponse acoustique d'un profil isolé avec un bord d'attaque ondulé conçu et testé dans la soufflerie de l'ISVR dans le cadre du projet européen FLOCON. Enfin, la méthodologie est étendue à des configurations de grilles d'aubes annulaires en conduit. Après une étape de validation sur des cas monofréquentiels issus d'un benchmark CAA, des simulations large bande sont réalisées, tout d'abord sur une configuration de grille d'aubes sans incidence (écoulement axial uniforme) testée en soufflerie au LMFA, puis sur une configuration plus complexe de grille d'aubes non chargée en écoulement tournant proposée par AtassiNoise generation due to the rotor wakes impinging the stator vanes is a dominant turbofan source at approach conditions, and the broadband noise component is significantly contributing to the overall level. A numerical method based on a CAA code solving the Euler equations is developped in this thesis in order to simulate the interaction noise between a turbulent wake and a vane row without geometry restrictions. The upstream turbulent flow is synthesized using a stochastic approach by considering an homogeneous isotropic turbulence spectrum model and a simplified spatial representation of the velocity field. These velocity gusts are injected in the CAA code by implementing a suited boundary condition. The present methodology is first va- lidated against turbulence-flat plate interaction cases, by comparing the numerical predictions to Amiet model solutions. A chaining with an integral formulation is also performed to assess the acoustic far-field. Then, the method is used to estimate the acoustic response of an isolated airfoil with a wavy leading egde, designed and tested in ISVR wind tunnel in the framework of European FLOCON project. Finally, the computations are extended to ducted annular grid configurations. After a validation step on single-frequency cases described in a CAA benchmark, broadband noise simulations are performed, firstly on a flat-plate annular grid in a uniform axial flow tested in the LMFA wind tunnel, and then on a more complex configuration related to an unloaded grid in a swirling mean flow proposed by Atassi
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Kong, Jianfeng. "Evidence for pH-dependent conformations in the catalytic cycle of cytochrome caa¦3 from B. subtilis." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0004/MQ45281.pdf.
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Lavandoscki, Rogerio. "Estudo das propriedades mecânicas de cabos condutores elétricos de tipo CAA usados e sua adequação ao retracionamento." Universidade Federal de São Carlos, 2005. https://repositorio.ufscar.br/handle/ufscar/752.
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Previous issue date: 2005-10-24Diversas linhas aéreas de transmissão de energia elétrica (LTs) foram construídas numa época em que o Brasil dispunha de pouca tecnologia para o desenvolvimento dos projetos e construção. Com isso, os projetos eram baseados em normas estrangeiras, que prescreviam distâncias entre os condutores elétricos e o solo abaixo dos valores hoje recomendados pela norma brasileira. Uma das alternativas para a correção do problema de cabos baixos é a reforma da linha de transmissão, quando pode ser empregado o processo de retracionamento para alteamento dos cabos CAA (Condutores de Alumínio com Alma de Aço). Este trabalho tem como objetivo, o estudo da influência do grampo de suspensão (fadiga e "fretting" - desgaste por atrito entre os fios do condutor e o grampo de suspensão) em determinadas propriedades mecânicas dos condutores usados, visto que esse ponto do condutor é deslocado para fora do grampo de suspensão quando da aplicação do retracionamento, além de ficar submetido a um valor de carregamento mecânico mais elevado. Esses estudos englobam a realização de ensaios de tração e vibração, além de análises metalográficas em amostras de cabos condutores completos usados (regiões dentro e fora do grampo de suspensão) e em condutores novos sem uso. Os resultados obtidos do ensaio de tração indicaram que, para os cabos estudados, não há uma influência direta da região do grampo nas propriedades mecânicas estáticas, como a carga de ruptura e alongamento percentual. Com relação ao ensaio de vibração, todas as amostras de cabos não apresentaram qualquer tipo de fratura, o que levou o ensaio a ser realizado até 10.000.000 de ciclos. As análises microestruturais mostraram a presença de marcas de fretting na parte da camada mais externa e interna dos condutores, mas apenas com danos muito superficiais. Dessa forma, pode-se concluir que, para o condutor estudado é possível a utilização do processo de retracionamento para a reforma da linha de transmissão.
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Virgens, Jeovan Pereira das. "Análise experimental de pilares de concreto armado, com carga excêntrica, reforçados com chumbadores e concreto autoadensável (CAA)." Universidade Federal de Goiás, 2015. http://repositorio.bc.ufg.br/tede/handle/tede/5403.
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Made available in DSpace on 2016-04-04T11:45:04Z (GMT). No. of bitstreams: 2 Dissertação - Jeovan Pereira das Virgens - 2015.pdf: 10009095 bytes, checksum: a8f3d2a6914adbb0c7cdcf49732ffc57 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2015-10-16
This paper presents the experimental study of reinforcement concrete columns reinforced with wedge bolts and a 35 mm self compacting concrete jacket at the most compressed face. Nine columns with a 2000 mm height subjected to flexure and bending with initial eccentricity of 60 mm, named as: original column (Po) with a cross section of 120 mm x 250 mm; reference column (Pref) with a cross section of 155 mm x 250 mm and seven columns with a initial cross section of 120 mm x 250 mm, and later reinforced by the addition of 35 mm reinforcing layer, and various configurations of wedge bolts at its most compressed face. Except for the original column (Po), the columns were submitted to a 42.5 mm load eccentricity due to the attached concrete layer at the compressed face. Although failure of the wedge bolts did not accour, it was not possible to prevent detachment of the reinforcing layer. The results indicate that it is possible to structural rehabilitate reinforce concrete columns with the use of the strengthening methodology used in this research, resulting in average load capacity gains of 3,71 times compared to original column load (Po).
O presente trabalho apresenta o estudo experimental de pilares de concreto armado reforçados com parafusos chumbadores e acréscimo de camada com 35 mm de concreto autoadensável na face comprimida. Nove pilares, com alturas de 2000 mm, foram submetidos à flexão composta reta com excentricidade inicial de 60 mm, assim discriminados: um pilar original (Po) com seção transversal de 120 mm x 250 mm; um pilar de referência (Pref) com seção transversal de 155 mm x 250 mm e sete pilares, inicialmente moldados com seção transversal de 120 mm x 250 mm, e após, reforçados através da adição de camada de reforço de 35 mm e diversas configurações de posições de parafusos chumbadores na face comprimida. Exceto o pilar original (Po), os pilares foram submetidos à excentricidade inicial de carga de 42,5 mm, devido ao acréscimo da camada de reforço na face comprimida. Apesar de não ocorrer ruptura dos parafusos chumbadores, não foi possível evitar o desplacamento da camada de reforço. Os resultados obtidos indicam que é possível a reabilitação estrutural de pilares de concreto armado com o uso da metodologia de reforço empregada, obtendo ganho de capacidade de carga média de 3,71 vezes em relação ao pilar original (Po).
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Goodchild, David Joseph. "The determinants of organisational performance in parts of the local British public services using CPA and CAA." Thesis, Teesside University, 2015. http://hdl.handle.net/10149/613549.
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The research investigated the factors that are associated with organisational performance in British local public services using the national assessment frameworks of Comprehensive Performance Assessment (CPA) and Comprehensive Area Assessment (CAA). Performance measurement was said by Behn (1995) to be one of the big questions of public management and the literature demonstrates this remains the case. More generally performance management has been the subject of a large number of studies, many in the private sector, that often consider a narrow spectrum of explanatory factors. This research is unusual in studying a relatively large number of possible explanations of performance using three different methods of inquiry: longitudinal questionnaire surveys of four types of local public service organisations, a content analysis of strategic documents and the use of organisational profiles regarding the post bureaucratic construct (Kernaghan, 2000). The research relied on the CPA and CAA results to provide an independent assessment of organisational performance; such data is not usually available for public services. CPA has been found to have driven up local government performance (Boyne, James and John et al, 2010) and therefore its use is very appropriate. The analysis used correlation to identify the significant (p<0.05) criteria which were then put through a principal component analysis (PCA). This resulted in the identification of 11 summary factors with the strongest five being Strategy, Performance management, Human resources, Culture and Engagement. Factors of lesser importance are Resources, Leadership, Reputation and Innovation. The term ‘summary factors’ has been used to denote that within each of these there are potentially a number of parts. The research can be used practically by organisations, to improve, by comparing their results on the questionnaire with the criteria associated with high organisational performance. Further, the summary factors provide confidence regarding what may be the most critical areas to be addressed.
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Fassina, Elena <1997>. "LIS come CAA: un supporto per l'apprendimento dell'italiano da parte di una bambina straniera con disabilità intellettiva." Master's Degree Thesis, Università Ca' Foscari Venezia, 2022. http://hdl.handle.net/10579/21766.
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Questo lavoro rappresenta uno studio di caso incentrato su una bambina bengalese, recentemente immigrata in Italia, affetta da ritardo cognitivo e difficoltà relazionali, oltre che comunicative. La bambina presa in esame è iscritta alla classe seconda di una scuola primaria della provincia di Venezia, ma non è seguita da nessun insegnante di sostegno in quanto la sua disabilità non risulta essere stata ancora certificata. In più, essendo priva di un’adeguata competenza linguistica sia nella sua L1 che in italiano, trovare un modo per riuscire ad interagire efficacemente con gli altri non è scontato per lei. L’obiettivo di questo lavoro si focalizza quindi sul tentativo di trovare un modo per agevolare la suddetta bambina nella comprensione e produzione linguistica, soprattutto per quanto riguarda l’italiano, con lo scopo di permetterle una migliore integrazione all’interno della classe. Per facilitare e supportare l’apprendimento dell’italiano e la memorizzazione di vocaboli di uso quotidiano, è stata scelta una particolare forma di CAA che include la LIS. Grazie a quest’ultima, dopo un periodo di training e di osservazione della bambina, sono stati registrati alcuni miglioramenti, i quali si sono dimostrati utili in relazione ai progressi da lei compiuti sia nei rapporti con i coetanei, sia in quelli con il corpo docente.
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COELHO, F. Z. "AVALIAÇÃO DO CICLO DE VIDA CRADLE-TO-GATE DE MISTURAS DE CONCRETOS AUTOADENSÁVEIS COM INCORPORAÇÃO DE RESÍDUOS E SUBPRODUTOS INDUSTRIAIS." Universidade Federal do Espírito Santo, 2016. http://repositorio.ufes.br/handle/10/9471.
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tese_10450_DISSERTAÇÃO FELIPE ZANELLATO COELHO COMPLETA PDF.pdf: 5435895 bytes, checksum: 0407e27924b1cfbdf97715466ba0e4d6 (MD5)
Previous issue date: 2016-09-05A incorporação de resíduos e subprodutos industriais nos traços de concreto é uma solução para minimizar os impactos causados pelos processos produtivos dos materiais que o compõem. Vários estudos avaliam o desempenho técnico da incorporação de resíduos e subprodutos industriais nos traços de concreto, porém para decidir qual mistura apresenta a menor carga ambiental é necessário fazer uma análise completa de todo seu ciclo de vida. A avaliação do ciclo de vida (ACV) é uma metodologia para avaliar os potenciais impactos ambientais e os recursos utilizados ao longo do ciclo de vida de um produto. Portanto, o objetivo desta dissertação consiste no desenvolvimento de uma ACV comparativa para analisar 162 traços de Concretos Autoadensáveis (CAA) com altas proporções de incorporação de resíduos e subprodutos industriais em um cenário na cidade de Berkeley, Califórnia-EUA. A pesquisa aponta quantitativamente quais os traços que apresentam o melhor desempenho ambiental no cenário proposto. Os traços foram extraídos de 15 artigos científicos que comprovaram a viabilidade técnica dos concretos analisados. Os CAA's estão sendo cada vez mais utilizados para a construção de elementos de concreto complexos altamente reforçados e para estruturas de concreto maciço, como barragens e fundação que necessitam de misturas com maior fluidez. Para avaliar o desempenho ambiental dos CAA's os traços foram separados em 3 classes de resistência e analisados com o Software SIMAPRO, método de avaliação de impacto IMPACT 2002+, banco de dados ECOINVENT e unidade funcional de 1 m3. A ACV realizada desconsiderando as fases de pós-fabricação, ou seja, o limite do sistema é "cradle-to-gate". Os resultados mostram que as categorias de danos mais afetadas foram a Saúde Humana, Mudanças climáticas e os Recursos Energéticos por consequência das altas emissões de partículas respiratórias inorgânicas, emissão de GEE's e o consumo de energia não renovável respectivamente. O traço de menor impacto por categoria apresenta índices de emissões de partículas respiratórias inorgânicas, emissão de GEE's e o consumo de energia não renovável menor que o traço de maior impacto nas proporções de 57%, 65%, 55% respectivamente na classe 1A, 55%, 78%, 55% respectivamente na classe 1B e 49%, 78%, 51% respectivamente na classe 2. Em resumo, os ecoconcretos apresentam ganhos ambientais significativos que podem ajudar a minimizar o aquecimento global, reduzir o esgotamento dos recursos naturais e promover a construção verde.
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Buckridge, Steeve O. ""Dem caa dress yah!" : dress as resistance and accommodation among Jamaican women from slavery to freedom 1760-1890 /." The Ohio State University, 1998. http://rave.ohiolink.edu/etdc/view?acc_num=osu1273239678.
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Mahoney, James Scott, and n/a. "Clipped Wings: Management discourses during organisational change at Australia's Civil Aviation Authority." University of Canberra. Arts & Design, 2007. http://erl.canberra.edu.au./public/adt-AUC20081113.153047.
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Structural change in organisations is stressful for staff and the managers who must implement it. Most change programs use employee communication techniques to support change directions set by senior executive decision makers-dominant coalitions.
This research used a single case study to explain the context and management discourses of a major re-structure of an Australian Federal Government agency, the former Civil Aviation Authority (CAA), during the early 1990s. A content analysis examined the use of keywords in management discourses that argued the need for change. The keywords represented the two major change discourses: micro-economic reform and aviation safety regulation. A critical discourse analysis investigated the dominant coalition's discourse strategies to justify change. Content and process communication theories, and the role of framing in organisational change, were used to explain how employees may have reacted to change directions.
The research found that change directions were framed as an economic imperative that clashed with a traditional organisational culture that emphasised the primacy of aviation safety. It found that mixed messages by the two principal members of the dominant coalition who drove change exacerbated the clash.
The results suggest a need for further analysis of management discourses used to inform employees about structural change, especially in organisations that have legislative responsibilities. Further analysis of change messages framed by dominant coalitions could lead to a deeper understanding ofhow they affect employees and the change process.
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Zaczek, Kinga. "Development and evaluation of computer-aided assessment in discrete and decision mathematics." Thesis, Brunel University, 2015. http://bura.brunel.ac.uk/handle/2438/10973.
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This thesis describes the development of Computer-Aided Assessment questions for elementary discrete and decision mathematics at the school/university interface, stressing the pedagogy behind the questions’ design and the development of methodology for assessing their efficacy in improving students’ engagement and perceptions, as well as on their exams results. The questions give instant and detailed feedback and hence are valuable as diagnostic, formative or summative tools. A total of 275 questions were designed and coded for five topics, numbers, sets, logic, linear programming and graph theory, commonly taught to students of mathematics, computer science, engineering and management. Pedagogy and programming problems with authoring questions were resolved and are discussed in specific topic contexts and beyond. The delivery of robust and valid objective questions, even within the constraints of CAA, is therefore feasible. Different question types and rich feedback comprising text, equations and diagrams that allow random parameters to produce millions of realisations at run time, can give CAA an important role in teaching mathematics at this level. Questionnaires identified that CAA was generally popular with students, with the vast majority seeing CAA not only as assessment but also as a learning resource. To test the impact of CAA on students’ learning, an analysis of the exam scripts quantified its effect on class means and standard deviations. This also identified common student errors, which fed into the question design and editing processes by providing evidence-based mal-rules. Four easily-identified indicators (correctly-written remainders, conversion of binary/octal/hexadecimal numbers, use of correct set notation {…} and consistent layout of truth tables) were examined in student exam scripts to find out if the CAA helps students to improve examination answers. The CAA answer files also provided the questions’ facilities and discriminations, potentially giving teachers specific information on which to base and develop their teaching and assessment strategies. We conclude that CAA is a successful tool for the formative/summative assessment of mathematics at this level and has a positive effect on students’ learning.
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Emmanuelli, Ariane. "Numerical simulation and modelling of entropy noise in nozzle and turbine stator flows." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLC067.
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L'étude du bruit de combustion est motivée par l'augmentation de sa contribution relative au bruit émis par les moteurs aéronautiques actuels, ainsi que par son impact sur la conception de chambres de combustion à basse émission de NOx. Le bruit entropique est une source de bruit de combustion indirect générée par l'accélération de perturbations entropiques à travers les tuyères et les étages de turbine à l'aval de la chambre de combustion. Cette étude porte sur la simulation numérique et la modélisation du bruit entropique à travers une tuyère et un stator de turbine. Dans un premier temps, le bruit entropique est simulé dans une tuyère avec un code CAA (Computational AeroAcoustics) afin de valider un modèle 2D existant sous des hypothèses similaires. Les niveaux de bruit entropique et de diffusion acoustique obtenus par les deux méthodes sont en accord. Leur comparaison au bruit estimé par des modèles compacts et 1D montre que les effets bi-dimensionnels sont significatifs. De plus, de la vorticité induite par l'accélération de perturbations entropiques est identifiée, mais celle-ci ne contribue pas significativement au bruit généré. Une géométrie de stator de turbine haute pression est ensuite étudiée en 2D. Le modèle pour les tuyères 2D est étendu à ces configurations, héritant de certaines de ses hypothèses. L'étude de celles-ci montre que l'impact de la vorticité et des variations azimutales des fluctuations acoustiques, négligées par le modèle, est significatif. Ces hypothèses devront être relaxées lors de développements futurs. Les calculs CAA permettent également de caractériser la génération de bruit entropique sous hypothèses simplificatrices avec à la fois des champs porteurs Euler et RANS. Une étude plus approfondie du cas RANS est nécessaire pour sa validation, ainsi que pour mieux comprendre le rôle de la couche limite dans la génération du bruit entropique. Enfin, un canal de stator est étudié par des calculs ZDES (Zonal Detached Eddy Simulation) afin d'examiner les effets 3D et visqueux sur le bruit généré. La tri-dimensionnalité de l'écoulement est mise en évidence et les perturbations sont post-traitées en portant une attention particulière au filtrage des fluctuations hydrodynamiques et aux réflexions en parois. Les résultats obtenus par la CAA et la ZDES sont comparables, ce qui indique que la tri-dimensionnalité et la viscosité de l'écoulement ont un effet limité sur le bruit entropique généré dans un stator de turbineThe investigation of combustion noise is motivated by its growing relative contribution to the noise emitted by modern turbofan engines overall, as well as its effect on low NOx emission combustor design. Entropy noise is a source of indirect combustion noise, which is generated by the acceleration of heterogeneities, in this case entropy, downstream of the combustion chamber. This study consists of the investigation of entropy noise in nozzle and turbine stator flow using both analytical and numerical methods. Nozzle flow is considered first. A Computational AeroAcoustics (CAA) reference case is built for the validation of an existing two-dimensional semi-analytical model developed under similar assumptions. The levels of entropy noise and acoustic scattering estimated using both methods are in good agreement. Two-dimensional effects on entropy noise are highlighted, notably by comparison with compact and 1D models. In addition, vorticity induced by the acceleration of entropy noise is evidenced, but it yields negligible vortex sound. Next, the focus is shifted to a 2D high-pressure turbine stator. The 2D model for nozzle flow is extended to this configuration, inheriting some of its main assumptions. Their investigation, using CAA in particular, sets the path for future developments and allows insight to be gained into the role of both vorticity and azimuthal variation of acoustics, which are neglected by the model. CAA also allows to characterise entropy noise generation in 2D stator flow under simplifying assumptions, using Euler and RANS mean flows. Further investigation is needed to validate the RANS case and to fully understand the effect of boundary layers on entropy noise generation. Finally, entropy noise is simulated using Zonal Detached Eddy Simulation (ZDES) in a stator channel in order to investigate 3D and viscous effects on entropy noise. The three-dimensionality of the flow is highlighted and acoustic signals are carefully post-processed, ensuring hydrodynamic perturbations are correctly filtered and boundary reflections are minimised. The closeness of noise levels obtained using CAA and ZDES suggest three-dimensional and viscous effects have a limited impact on the entropy noise generated in turbine stator flow
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Al-hajri, Amina Obaid. "Computer assisted assessment in Oman : factors affecting student performance." Thesis, University of Plymouth, 2011. http://hdl.handle.net/10026.1/318.
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This thesis investigates the social and psychological factors that might affect Omani higher education students if computerised assessment was to be implemented. A review of the literature and the historical and cultural development in Oman suggested that a number of different variables might affect students‘ performance when taking computerised assessment. These factors which include gender, college of study and geographical region of residence may cause unwanted and selective differences in student performance which are not related to the content of the assessment. In addition, the potential effects of such variables as computer experience and computer self-efficacy on student performance were investigated. The study also explored student and academic staff attitudes towards computerised assessment. Both quantitative and qualitative methods are used in this study through a selection of instruments such as a test that was delivered in different modes, questionnaires, focus groups and semi-structured interviews. Quantitative approaches are used to provide answers to the main study questions about student performance, and qualitative approaches are used to get deeper insights into the students‘ and staff members‘ perceptions, attitudes and values in relation to the research subject of the study. All these instruments were developed based upon the literature and also validated through a separate initial study. The main study took place after the instruments had been validated and involved over 400 students and 100 staff at three Omani Applied Sciences Colleges. Statistical analysis showed a small but significant difference between the two assessment modes in favour of the paper-and-pencil test. There was a significant difference in performance between both genders, with females out-performing males. However, the most striking finding was a differential effect of assessment mode between males and females. Males performed better in the computerized test than in the paper-based one, in contrast to females whose performance in the paper test was better. This suggests that the introduction of computerised testing may affect males and females in different ways. One 4 possible explanation for this is that Omani males have more opportunities to use computers inside and outside homes. The questionnaire results and the qualitative information from focus groups both showed that females were more nervous and found it more difficult to read from the computer screen than males did. Also, it was obvious in the focus group discussions that females had more negative feelings towards computerised testing compared to males, both before and after experiencing computerised assessment. The study found that students‘ performance in the English language test had showed significant variation across colleges, and among students from different regions. This variation seemed to be associated with variation in computer experience among students at the different colleges and from different regions. This may be due to regional differences or specificities, especially in terms of computer use, among the nine administrative regions in Oman. Staff attitudes and perceptions towards CAA, in general, were positive and not affected by either the gender or nationality/language factor. Most of the academic staff members revealed their willingness to implement CAA but also stressed that CAA should be gradually implemented. Both students and staff members identified a number of important points such as the need for a reliable system, qualified technicians and sufficient computers if Computer Assisted Assessment was to achieve wide acceptability.
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Switzer, Earl R., and Amy D. Fleishans. "Progress in Global Air Traffic Management (GATM) Avionics System Test at the Air Force Flight Test Center." International Foundation for Telemetering, 2001. http://hdl.handle.net/10150/606465.
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International Telemetering Conference Proceedings / October 22-25, 2001 / Riviera Hotel and Convention Center, Las Vegas, NevadaThis paper presents a progress report on Global Air Traffic Management (GATM) avionic system test activities at the Air Force Flight Test Center. In many parts of the world today the continuing growth of commercial air traffic is running up against limits brought on by overuse of aviation resources. Air corridors in Europe and on transoceanic air routes are operating at maximum capacity. Civil Aviation Authorities (CAAs) are working these challenges on two levels—near-term incremental improvements and long-term visionary changes. Each country has a CAA; ours being the Federal Aviation Administration (FAA). Near-term solutions focus on better utilization of resources such as air space and frequency spectrum and improved performance of air traffic control facilities. Long-term visionary changes, such as free flight, could fundamentally change the current civil aviation business process model. CAA policies and standards are driving near-term improvements and migration toward long-term objectives. This initiative is referred as Communication Navigation Surveillance/Air Traffic Management (CNS/ATM). Implementation of the U.S. military’s vision, Global Reach/Global Power, requires the ability to rapidly deploy armed forces to major regional conflicts anywhere in the world, and to sustain these forces for as long as it takes to resolve these conflicts. To achieve this goal and accomplish rapid deployments while at the same time minimizing costs, the Air Force has adopted a solution that makes extensive use of CNS/ATM. The Air Force calls its initiative Global Air Traffic Management (GATM). Air Force aircraft equipped with GATM avionics will be able to use CNS/ATM capabilities such as reduced vertical separation minimum (RVSM), 8.33 kHz data links, automatic dependent surveillance - broadcast (ADS-B), and global communication networks. These capabilities make possible improved flight safety, lower fuel costs, and quicker turn times. The Air Force Flight Test Center supports the GATM initiative by providing Air Traffic Control (ATC) Communications Test Facilities and Avionic System Test (ACTFAST) capabilities to support aircraft modification programs.
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Desquesnes, Guillaume. "Couplage par recouvrement de maillages curviligne/cartésien pour la simulation en aéroacoustique." Paris 6, 2007. http://www.theses.fr/2007PA066418.
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La simulation numérique en aéroacoustique (CAA) est en fort développement depuis ces dix dernières années. Cette thèse s'intègre dans le cadre de l'extension du champ d'applications des méthodes CAA basées sur les schémas aux différences finies d'ordre élevé, en maillage structuré. En effet, l'utilisation de ce type de maillage s'accompagne d'une certaine raideur de mise en oeuvre. L'enjeu de la thèse est de mettre en place un outil - le couplage par recouvrement - permettant de surmonter cette difficulté. Cette approche est comparable aux méthodes « Chimère » en CFD. Dans ce mémoire, un couplage à un sens et à deux sens est proposé (en 2D et en 3D). Une analyse originale de l'interpolateur de Lagrange est présentée ; les phénomènes prédits par l'analyse étant ensuite effectivement observés dans certains cas sur les simulations. Pour chaque type de couplage, l'approche est validée sur des configurations académiques (diffraction acoustique sur cylindre, bruit d'écoulement autour d'un cylindre), et ensuite, mise en oeuvre sur des configurations industrielles (bruit de profil d'aile hyper-sustenté, effet d'installation motrice). En parallèle, la première étude numérique du phénomène "tone noise" (lié au bruit de profil) est menée. Il est montré que la simulation reproduit bien le phénomène observé en soufflerie. De plus, l'étude confirme les hypothèses tentant d'expliquer ce phénomène. Enfin, elle propose une interprétation originale de la forme particulière du spectre qui est observée dans certains cas. Ainsi, il est montré que la simulation numérique peut être un outil performant et complémentaire à l'expérience pour la compréhension de la physique des écoulements.
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Williams, Catherine E. "The circulation and fluxes from the Arctic into the North Atlantic Ocean 1979-2002 model results." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2004. http://library.nps.navy.mil/uhtbin/hyperion/04Sep%5FWilliams.pdf.
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Thesis (M.S. in Applied Science (Physical Oceanography))--Naval Postgraduate School, Sept. 2004.Thesis Advisor(s): Wieslaw Maslowski. Includes bibliographical references (p. 87-90). Also available online.
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COSTA, Jéssica Flaíne dos Santos. "As contribuições do ENADE para o curso de pedagogia da UFPE-CAA: um olhar para o percurso formativo de pedagogos/as." Universidade Federal de Pernambuco, 2017. https://repositorio.ufpe.br/handle/123456789/28834.
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FACEPE
A intencionalidade desta pesquisa, intitulada “As contribuições do ENADE para o curso de Pedagogia da UFPE-CAA: um olhar para os percursos formativos de pedagogos/as”, centra-se em compreender de que formas os resultados do ENADE têm sido levados em consideração pela coordenação e equipe docente do curso de Pedagogia, bem como pelos membros da Comissão Própria de Avaliação (CPA) da UFPE, para aperfeiçoamento da formação oferecida aos licenciandos, tendo, assim, como objetivos específicos: Investigar como os resultados do ENADE têm chegado à UFPE-CAA, especificamente ao curso de Pedagogia; Analisar de que maneiras os resultados apontados pelo ENADE são considerados pelos/as coordenadores/as e pelos/as docentes do curso de Pedagogia, bem como pela Comissão Própria de Avaliação (CPA) da instituição. Diante disto, buscamos um aprofundamento epistemológico das questões relacionadas ao percurso histórico e as contribuições engendradas pela avaliação educacional e pelas políticas avaliativas do ensino superior no Brasil, lançando mão dos estudos de Vianna (1995; 2000), Gatti (2002; 2011; 2014), Sobrinho (2002; 2010), da lei do SINAES, 10.861/2004, entre outros. A UFPE-CAA, figura como nosso campo de pesquisa por ser uma IES pública, fruto da política do REUNI, uma das ações que integraram o Plano Nacional da Educação (PNE), instituído pela Lei nº 10.172/2001. Esta escolha caracteriza o nosso procedimento investigativo como Estudo de Caso, sob as óticas de Stake (1982), Yin (1994) e Mazzotti (2006). Para colaborar com a coleta de dados, elegemos 4 coordenadores do curso de Pedagogia, 7 docentes, por serem estes os que são responsáveis pelo recebimento dos resultados do ENADE em relação à apreciação, discussão e promoção de melhorias no currículo do curso. Escolhemos também 4 membros da CPA da instituição, por desempenharem funções referentes a autoavaliação, elaborando relatórios sobre as condições físicas-estruturais e pedagógicas, que se somarão a avaliação externa realizada pelo INEP. Utilizamos como fonte de coleta de dados, a entrevista semiestruturada, gravada em áudio. Estabelecemos enquanto Corpus documental, o PPC do curso de Pedagogia e o relatório do INEP, referente ao último ENADE. Para análise dos dados, adotamos a Análise do Discurso, na perspectiva de Orlandi (2013; 2016), afim de alcançarmos os sentidos atribuídos às repercussões da realização do ENADE pelos/as estudantes da IES. Ao nos debruçarmos sobre os dados, foi possível constatar que o curso de Pedagogia apresenta uma proposta avaliativa interna formativa em sua base documental, legal, no entanto os colaboradores da pesquisa desconsideram os resultados da avaliação de larga escala, proposta pelo Sistema Nacional de Avaliação do Ensino Superior (SINAES), enquanto possibilidade de aprimoramento da qualidade educacional, pois não chegam a promover momentos voltados à apreciação dos resultados do ENADE, por acreditarem na dispensabilidade destes e na descontextualização da política de avaliação externa, ao apontarem que esta deixa a desejar no que diz respeito a contemplação das características próprias e específicas que compõem a realidade do curso em questão, bem como as necessidades formativas de seus/as estudantes.
The intentionality of this research, entitled "The contributions of the ENADE to the course of Pedagogy of the UFPE-CAA: a look at the formative paths of Pedagogues / like", focuses on the enunciation of forms of ENADE results have been taken the considerations By CPA, of UFPE, for the improvement of the training offered to the graduates, having, as, specific objectives: To investigate how the results of ENADE have arrived at the UFPE-CAA, specifically to the Pedagogy course; Analyze of ways and results on behalf of ENADE are essential by the coordinators / as and by the teachers of the Pedagogy course as well as by the institution's own Evaluation Committee (CPA). The objective of the study is to evaluate, for example, the results of higher education and educational education and public higher education policies in Brazil, using the studies of Vianna (1995, 2000), Gatti (2002, 2011, 2014), Sobrinho (2002, 2010), of the SINAES law, 10,861 / 2004, among others. UFPE-CAA, figure as our field of research for being a public HEI, a product of the policy of REUNI, one of the actions that integrate the National Education Plan (PNE), instituted by Law 10,172 / 2001. Establish our study as a study (1982), Yin (1994), and Mazzotti (2006). In order to collaborate with a data collection, we chose 4 pedagogy course coordinators, 7 teachers, as they are responsible for receiving the results of ENADE in relation to the appreciation, discussion and promotion of improvements in the curriculum of the course. We also chose 4 members of the CPA, for performing functions related to self-assessment, elaborating information about the physical-structural and pedagogical conditions, which will be added to the external evaluation by the INEP. We used as a source of data collection, a semi-structured interview, recorded in audio. We established as documentary Corpus, the PPC of the Pedagogy course and the INEP report, referring to the last ENADE. To analyze the data, we adopted Discourse Analysis, from Orlandi's perspective (2013, 2016), in order to reach the senses attributed to the repercussions of ENADE's achievement by IES students. When we look at the data, it was possible to verify that the Pedagogy course presents a proposal of internal formative evaluation in its documentary, legal basis, however, the research collaborators disregard the results of the large scale evaluation, proposed by the National System of Evaluation of Higher Education (SINAES), Considering the possibility of improving educational quality, it is not an innovative method, but it is not an innovative method, but it is not an innovative method. It concerns the contemplation of the own and specific technologies that make up the reality of the course in question, as well as the formative needs of its students.
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Fadel, Aida Alves. "Avaliação do efeito de tracionamento em elevados níveis de EDS sobre a resistência em Fadiga do Condutor IBIS (CAA 397,5 MCM)." reponame:Repositório Institucional da UnB, 2010. http://repositorio.unb.br/handle/10482/6023.
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Tese (doutorado)-Universidade de Brasília, Faculdade de Tecnologia, Departamento de Engenharia Mecânica, 2010.Submitted by Suelen Silva dos Santos (suelenunb@yahoo.com.br) on 2010-11-24T17:57:45Z No. of bitstreams: 1 2010_AidaAlvesFadel.pdf: 12583940 bytes, checksum: 5397d2e3fff17d1e58735f16c0504567 (MD5)
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O presente trabalho é de natureza experimental e, visa apresentar uma avaliação da influência da carga de esticamento aplicada a cabos condutores de energia elétrica, sobre a vida útil destes elementos. O estudo, baseado na análise da resistência à fadiga por fretting, tem como foco o levantamento da curva Curva de Wöhler ou S-N de determinada montagem cabo/grampo. Para tal, foi realizado um total de 41 ensaios de vibração em amostras de 41,5m de comprimento do cabo IBIS (CAA 397,5 MCM)/ grampo de suspensão mono articulado submetidas a cargas de esticamento referentes à carga média diária de tração, conhecida como EDSi (Every Day Stress) de 20% e 30%. Os ensaios foram executados, de acordo com as recomendações da CIGRE (1985), EPRI (1979) e IEEE (1978), em uma bancada de 46,8 metros de comprimento, em ambiente climatizado, com sistema de controle dos equipamentos totalmente automatizado. Testes adicionais foram realizados para determinar o erro inserido pela fórmula de Poffenberger-Swart (1965), P-S, que é uma expressão numérico-empírica usada para correlacionar o nível de tensão nominal (na região da falha) ao deslocamento provocado pela vibração no cabo (medido em uma posição padrão a partir do grampo de suspensão). Para a combinação cabo-grampo usada, a curva experimental obtida foi comparada à Curva Limite de Segurança da CIGRE (CSBL), que é empregada no projeto das linhas de transmissão, apresentando vidas 4,5 a 13,5 vezes maiores do que as previstas pela curva padrão CSBL. A vida da mesma montagem sofreu uma redução de cerca de 50% quando a carga foi elevada da EDS de 20% para 30%. Neste trabalho são ainda avaliadas as características associadas ao aspecto e posicionamento das falhas obtidas em cada amostra de cabo ensaiada, na tentativa de definir um padrão de falhas para diferentes níveis de EDS e amplitude. _________________________________________________________________________________ ABSTRACT
The aim of this experimental work is to evaluate the effects of aeolian vibration, concerned to the reduction of aerial conductor´s life, when these structures are subjected to high levels of EDSii (Every Day Stress). The study, based on fretting fatigue resistance has it focus on the construction of a Wöhler Curve for a chosen cable/clamp set. A total of 41 vibration experiments has been conducted on IBIS (CASR 397,5 MCM) conductor samples, which were attached by a monoarticuled suspension clamp to an experimental rig. Samples were, tested with EDS of 20% and 30% Tests were performed according to CIGRE (1985), EPRI (1979) e IEEE (1978) recommendations in a rig fully instrumented and closed loop controlled, with a total span of 46,8 meters operating on a climatized environment. Further tests using strain gauges were performed to determine the amount of error that is carried on the stress calculation by the application of Poffenberger-Swart formula (P-S), (1965) which is an analytical experimental expression used to correlate nominal stress level (at the failure region) to vibration displacement (measured at a standard distance from the clamp). The fretting fatigue resistance limits, measured through the experimental procedure, were then compared to the limits imposed by CIGRE on its Save Border Line curve, which is applied as design standard for energy lines, revealing that CIGRE´s design guideline is very conservative, since the life prescribed by the curve is 4,5 to 13,5 times smaller than the measured ones. Tested samples presented an average life reduction of 50 % when EDS was increased from 20 to 30%. Position and characteristics of superficial aspect and of the failures (macro and microscopic) were also compared in order to try to establish a common pattern for each different level of vibration displacement and EDS.
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Nogueira, Leon White. "Otimização acústica e análise numérica do escoamento ao redor de um conjunto cilindro-placa separadora." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/3/3150/tde-13072016-150044/.
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RESUMO Simulações de aeroacústica computacional demandam uma quantidade considerável de tempo, o que torna complicada a realização de estudos paramétricos. O presente trabalho propõe uma metodologia viável para otimização aeroacústica. Através da análise numérica utilizando dinâmica dos fluidos computacional, foi estudada a aplicação de uma placa separadora desacoplada como método de controle passivo da esteira turbulenta de um cilindro e avaliou-se a irradiação de ruído causado pela interação do escoamento com ambos os corpos, empregando ferramentas de aeroacústica computacional baseadas no método de Ffowcs-Williams e Hawkings. Algumas abordagens distintas de metodologias de otimização de projeto foram aplicadas neste problema, com o objetivo de chegar a uma configuração otimizada que permita a redução do nível sonoro ao longe. Assim, utilizando uma ferramenta de otimização multidisciplinar, pode-se avaliar a capacidade de modelos heurísticos e a grande vantagem do emprego de algoritmos baseados em método de superfície de resposta quando aplicados em um problema não linear, pois requerem a avaliação de um menor número de alternativas para se obter um ponto ótimo. Além disso, foi possível identificar e agrupar os resultados em 5 clusters baseados em seus parâmetros geométricos, nível de pressão sonora global e o valor quadrático médio do coeficiente de arrasto, confirmando a eficiência da aplicação de placas separadoras longas desacopladas posicionadas próximas ao cilindro na estabilização da esteira turbulenta, enquanto que o posicionamento de placas acima de um espaçamento crítico aumentou o nível de pressão acústica irradiado devido à formação de vórtices no espaço entre o cilindro e a placa separadora.Computational aeroacoustics simulations require a considerable amount of time, which makes the comparison of a large number of different geometric designs a difficult task. The goal of the present study is to provide a suitable methodology for aeroacustic optimization. By means of numerical analyses using computational fluid dynamics tools, the application of a detached splitter plate as a passive control method for the turbulent wake of a circular cylinder was investigated. The irradiation of noise caused by the interaction between the flow and both bodies was evaluated using computational aeroacoustics tools based on the Ffowcs-Williams and Hawkings method. Various design optimization methodologies were applied to this flow in order to achieve a possible optimal configuration, i.e., one which is capable of reducing the far field noise level without increasing the aerodynamic forces. Using a multidisciplinary optimization tool, it was possible to evaluate the behavior of heuristic optimization algorithms and the major advantage of algorithms based on response surface methods when applied to a nonlinear aeroacoustics problem, since they require a smaller number of calculated designs to reach the optimal configuration. In addition, it was possible to identify and group the outcomes into 5 clusters based on their geometric parameters, overall sound pressure level and drag coefficient, confirming the efficiency of the application of long detached splitter plates placed next to the cylinder in stabilizing the turbulent wake, whereas the positioning of splitter plates at a distance larger than a critical gap increased the overall sound pressure level radiated due to the formation of vortices in the gap.
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Slivko, Giedrė. "Biologinių neuronų mokymosi savybių tyrimas." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2008. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2008~D_20080902_100150-63821.
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Ankstesni tyrimai, susiję su laikinėmis sinapsinio efektyvumo pasikeitimo taisyklėmis per nuo veikimo potencialų poravimo priklausantį plastiškumą, praktiškai nekreipė jokio dėmesio į neuronų erdvines savybes. Mes nagrinėjame nuo kalcio/kalmodulino priklausančią kinazę II (CaMKII) ir kalcineuriną (CaN) artimuosiuose ir tolimuosiuose spygliuose bei jų įtaką ilgalaikei potenciacijai ir ilgalaikei depresijai. Tyrimų metu buvo atskleista, kad esant neigiamam veikimo potencialų laiko poravimui tolimoje sinapsėje gali vykti ilgalaikė potenciacija, tuo tarpu artimajame spyglyje visi procesai vyksta remiantis klasikinėmis sinapsinio plastiškumo taisyklėmis. Gauti rezultatai teigia, kad sinapsės vieta dendritiniame medyje yra lemiamas veiksnys nuo veikimo potencialų laikų poravimo priklausančiame sinapsiniame plastiškume.Previous studies focusing on the temporal rules governing changes in synaptic efficacy during spike timing-dependent plasticity (STDP) have paid little attention to spatial characteristics of neurons. We analyze the activity of calcium-calmodulin dependent protein kinase II (CaMKII) and phosphatase calcineurin (CaN) in proximal and distal spines and their impact on long-term potentiation (LTP) and long-term depression (LTD). During tests we found that at negative timing of action potentials in distal spine synapse can undergo LTP while in proximal spine the processes follow the classic STDP rules. Our results suggest that synapse location within the dendritic tree is a crucial determinant of STDP.
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Rannikmäe, Kristiina. "Genetic associations with sporadic cerebral small vessel disease." Thesis, University of Edinburgh, 2017. http://hdl.handle.net/1842/23585.
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Background: Cerebral small vessel disease (SVD) causes substantial cognitive, psychiatric and physical disabilities. Despite its common nature, SVD pathogenesis and molecular mechanisms remain poorly understood, and prevention and treatment are probably suboptimal. Identifying the genetic determinants of SVD will improve understanding and may help identify novel treatment targets. The aim of this thesis is to better understand genetic associations with SVD through investigating its pathological, radiological and clinical phenotypes. Methods: To unravel the genetic associations with SVD, I used three complementary approaches. First, I performed a systematic review looking at existing intracerebral haemorrhage (ICH) classification systems and their reliability, to help inform future studies of ICH genetics. Second, I performed a series of systematic reviews and meta-analyses, investigating associations between genetic polymorphisms and histopathologically confirmed cerebral amyloid angiopathy (CAA). Third, I performed meta-analyses of existing genome-wide datasets to determine associations of >1000 common single nucleotide polymorphisms (SNP) in the COL4A1/COL4A2 genomic region with clinico-radiological SVD phenotypes: ICH and its subtypes, ischaemic stroke and its subtypes, and white matter hyperintensities. Results: The reliability of existing ICH classification systems appeared excellent in eight studies conducted in specialist centres with experienced raters, although these existing systems have several limitations. In my systematic evaluation of CAA genetics, meta-analyses of 24 studies including 3520 participants showed robust evidence for a dose-dependent association between APOE ɛ4 and histopathological CAA. There was, however, no convincing association between APOE ɛ2 and presence of CAA in a meta-analysis of 11 studies including 1640 participants. Meta-analyses of five studies including 497 participants showed, contrary to an existing popular hypothesis, that while APOE 4 may increase the risk of developing severe CAA vasculopathy, there is no clear evidence to support a role of ɛ2. There were few data about the role of APOE in hereditary CAA, but in the three studies that had looked at this, there was no evidence for an association between APOE ɛ4 and CAA severity. There were too few studies and participants to draw firm conclusions about the effect of non-APOE ε2/ε3/ε4 genetic polymorphisms on CAA, but there were positive associations with TGF-β1, TOMM40 and CR1 genes in four studies. Finally, in my meta-analyses of the COL4A1/COL4A2 genomic region, three intronic SNPs in COL4A2 were associated with SVD phenotypes: significantly with deep ICH, and suggestively with lacunar ischaemic stroke and WMH. Conclusions: I have shown that while existing ICH classification systems appear to have very good reliability, further research is needed to determine their performance in different settings. For large population-based prospective studies of ICH genetics, anatomical systems are likely to be more feasible, scalable and appropriate, although they have limitations and will need to be further developed. Using systematic reviews and meta-analyses, I have confirmed a dose-related association between APOE ɛ4 and histopathological CAA, but also demonstrated that, despite popular acceptance, there is insufficient data to draw firm conclusions about the association with APOE ɛ2. I found some positive associations with CAA in other genes, which merit replication in further larger studies, and showed that there is currently insufficient data about the role of APOE in hereditary CAA. Finally, I identified a novel association between a locus in a known hereditary SVD gene – COL4A2 – and sporadic SVD. This highlights a new and successful approach for selecting candidate genes and can be expanded in future studies to include other known hereditary SVD genes.
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ALMEIDA, Eliene Amorim de. "A interculturalidade no currículo da formação de professoras e professores indígenas no Programa de Educação Intercultural da UFPE/CAA - curso de Licenciatura Intercultural." Universidade Federal de Pernambuco, 2017. https://repositorio.ufpe.br/handle/123456789/25637.
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CAPES
Essa pesquisa teve como objetivo compreender a interculturalidade no primeiro curso de formação para professoras e professores indígenas oferecido pelo Centro Acadêmico do Agreste na Universidade Federal de Pernambuco. A interculturalidade no currículo da formação das(os) docentes indígenas foi analisada no contexto do Pensamento Decolonial, através das noções de Colonialidade (QUIJANO, 2005, 2010), Diferença Colonial (MIGNOLO, 2003, 2008, 2010); Desobediência Epistêmica (MIGNOLO, 2008), Interculturalidade (TUBINO, 2005; WALSH, 2006, 2008, 2009a, 2009b, 2010) além da categoria currículo, baseados em Santiago (1990, 2006); Silva, T. T. (2000, 2011); Arroyo (2008, 2012); Macedo (2008, 2011). Os dados foram coletados através da análise de documentos do MEC e da UFPE e a pesquisa de campo foi realizada através de grupo focal (GATTI, 2005) com as(os) estudantes Xukuru egressos do primeiro curso de licenciatura Intercultural da UFPE/CAA. Na análise dos dados, utilizamos as técnicas da Análise de Conteúdo, através da Análise temática (BARDIN, 2004; LEITE, 2002; VALA, 1999). Os dados mostram a interculturalidade nos documentos analisados como um termo polissêmico e polivocal, ora sendo apresentado como interculturalidade funcional, ora na perspectiva crítica, confirmando o que o nosso referencial teórico já anunciava. No que diz respeito às falas das(os) estudantes, identificamos uma distância no que anuncia o PPC/UFPE/CAA e a sua realização na prática, além disso, as falas das(os) estudantes indicam uma outra perspectiva de interculturalidade, ou seja, os indígenas entendem que um curso de formação para/com elas(es) deve tomar a interculturalidade como interepistemologias de forma a superar o racismo epistêmico próprio do sistema mundo moderno colonial patriarcal.
This research aimed to understand interculturalism in the first training course for indigenous teachers offered by Agreste Academic Center at the Federal University of Pernambuco. Interculturality in the curriculum of the training of indigenous teachers was analyzed in the context of Decolonial Through by notions of Coloniality (QUIJANO, 2005, 2010), Colonial Difference (MIGNOLO, 2003, 2008, 2010); Epistemic Disobedience (MIGNOLO, 2008), Interculturalism (TUBINO, 2005; WALSH, 2006, 2008, 2009a, 2009b, 2010), in addition to the curriculum category, based in Santiago (1990, 2006); Silva, T. (2000, 2011); Arroyo (2008, 2012); Macedo (2008, 2011). Data were collected through the MEC and UFPE document analysis and the field research was conducted through focus group (GATTI, 2005) with the students Xukuru graduates of the first Intercultural degree course of UFPE / CAA. In the data analysis, we used the techniques of Content Analysis, through the Thematic Analysis (BARDIN, 2004; LEITE, 2002; VALA, 1999). The data shows the interculturalism in the documents analyzed as a polysemic and polivocal term, being presented as functional interculturalism, and in critical perspective, confirming what our theoretical framework already announced. Regarding the speech of students we identified a distance in advertising PPC / UFPE / CAA and its implementation in practice, in addition, the lines of the speech of the students shows another perspective of interculturalism, ie, the Indians understand that a training course for / with them should take interculturalism as interepistemologias in order to overcome the epistemic racism own the modern world patriarchal colonial system.
Cette recherche a eut pour objectif comprendre l'interculturalité présente dans le premier cursus de formation offert par le centre académique do Agreste - université fédérale de Pernambuco - destiné aux professeurs/es autochtones. L´approche d´interculturalité a été examinée à partir des apports du courant décoloniel, plus précisemment, des notions de Colonialité (QUIJANO, 2005, 2010), de Différence Coloniale (MIGNOLO, 2003, 2008, 2010); de Désobéissance Èpistémique (MIGNOLO, 2008), d'Interculturalisme (TUBINO, 2005; WALSH, 2006, 2008, 2009a, 2009b, 2010) et celle de curriculum (SANTIAGO 1990, 2006; SILVA T.T., 2000, 2011; ARROYO, 2008, 2012 ; MACEDO, 2008, 2011). Les données analysées pour cette recherche proviennent des documents produits par le Ministère d´Education et Culture (MEC) et par l´Université fédérale de Pernambuco, mais aussi de la recherche de terrain menée auprès des étudiants Xukuru (UFPE/CE) à travers de discussions en groupe focal (GATTI, 2005). Pour analyser l´ensemble des données recueillies nous utilisons les techniques d'Analyse de Contenu, et celle de Thématique (BARDIN, 2004; LEITE, 2002; VALA, 1999). Les résultats montrent que, dans les documents examinés, le terme d´interculturalité aparaît de façon polysémique et polivocal, soit il fait référence à l´interculturalisme fonctionnel, soit il s´incrit dans une perspective plus critique ; ce qui confirmme notre apport théorique du départ. A partir des discussions établies avec les étudiants, nous avons pu identifier une distance entre ce que le PPC / UFPE / CAA afirme/propose et les pratiques mises en oeuvre par leus responsable / dirigeants. En outre, nous avons observés aussi que la perspective d´interculturalité avancée par le peuple autochtone, qui ont participés à la formation au CAA, renvoie à l´idee de interépistémologies. D´après eux, cette perspective peut aider à surmonter le racisme épistémique propre du système-monde moderne colonial et patriarcal.
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Rife, M. E. "Large eddy simulations of high Reynolds number jets with microjet injection." Thesis, Loughborough University, 2014. https://dspace.lboro.ac.uk/2134/14686.
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Continued growth of the aviation industry and increasingly strict noise requirements set by international bodies and airport authorities alike means that novel methods of reducing aircraft noise must be found. Engine noise represents a majority contribution to total aircraft noise during take-off and turbulent mixing of the exhaust gases is the dominant noise source of the engine at take-off. While bypass ratio has been the historical, and rather convenient means, of reducing jet noise, an upper limit to bypass ratio is now being approached and additional means of reducing jet noise must be found. One method that has shown potential for reducing aeroacoustic jet noise is the application of small, high pressure jets to the circumference of the jet nozzle. These jets, termed microjets, have the advantage over static devices that the microjets can be activated only when the noise benefit is required and deactivated when emitted noise is not an issue, such as in cruise, thereby reducing the thrust penalty associated with the devices over the majority of the flight. Large eddy simulations have been performed to investigate the impact that the addition of microjets has on the aerodynamic flowfield and radiated far-field noise of a high Reynolds number, Mach 0.9, propulsive, laboratory scale jet. Far-field noise was predicted through a new implementation of the permeable Ffowcs Williams Hawkings surface method in the solver. In addition to single-point flowfield statistics and far-field noise, spatio-temporal second- and fourth-order correlations are investigated. Two pairs of simulations were conducted, a coarse mesh containing 100 million elements and a fine mesh with 200 million elements. The coarse mesh included an azimuthal clustering of the cells in the near-microjet region. The non-uniformity of the azimuthal cell size was shown to adversely affect the development of the initial shear layer, yielding a delay in transition to a fully turbulent state and larger coherent structures in regions with larger cells. Radial velocity and turbulent kinetic energy profiles show good agreement with experimental results. A previously unidentified periodic interaction between the main jet and microjets was found. The dynamic interaction gives rise to velocity and pressure fluctuations in the near microjet region that match a tonal frequency found in the microjet far-field spectra that is absent from the clean jet case. Second- and fourth-order correlation distributions show large periodic regions of high correlation amplitude in the near microjet region. The evidence demonstrates that the main-microjet interaction is a clear high-frequency noise source. Despite the high-frequency noise associated with the main-microjet interaction, the addition of microjets yields a 1-2 dB reduction in overall sound pressure level. Additionally, over a significant portion of the length of the potential core the microjets reduce the amplitude of the majority of the six main correlation amplitudes that can be used in far-field noise prediction. Finally, the generation of the counter-rotating vortex pair downstream of the microjets was investigated. It is commonly presumed that this vortex pair is similar in origin to the counter-rotating vortex pair present in a jet in a crossflow. Vortex identification methods, velocity vectors and streamlines in the near microjet region demonstrate that the horseshoe-like vortex is the source of the counter rotating vortex pair that is present downstream of the microjets. The horseshoe-like vortex in the microjet case has the same sense as the vortices in the microjet shear layer and appears to be generated by the development of a recirculation region of microjet fluid during the main-microjet interaction.
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Unjum, Md Navid Unjum. "Analyzing the Efficiency of an Implicit Dual Time Stepping Solver for Computational AeroAcoustics." University of Toledo / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1501884344120742.
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Sousa, Mariana Silva. "Up-converting phosphor - lateral flow caa, kato-katz and poc-cca: a comparative analysis in Schistosoma mansoni infection diagnosis in a low endemic area." Universidade Federal do CearÃ, 2015. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=13457.
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Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgicoA esquistossomose acomete pelo menos 230 milhÃes de pessoas e està associada com pelo menos 200.000 mortes anualmente no mundo. A detecÃÃo dos antÃgenos circulantes de Schistosoma està se tornando uma ferramenta promissora para o diagnÃstico de infecÃÃes ativas. Os nÃveis sÃricos desses antÃgenos estÃo relacionados com a carga parasitÃria e a intensidade de infecÃÃo e diminuem rapidamente apÃs o tratamento medicamentoso, demonstrando ser uma abordagem Ãtil tambÃm na avaliaÃÃo da resposta terapÃutica. Foi avaliada a prevalÃncia da infecÃÃo ativa pelo S. mansoni atravÃs do ensaio Up- Converting Phosphor Lateral Flow (UCP-LF) para determinaÃÃo do AntÃgeno AnÃdico Circulante (CAA) na urina e comparada com a da tÃcnica de Kato-Katz para a detecÃÃo de ovos nas fezes e com a do teste Point-of-Care â CCA (POC-CCA), que detecta o AntÃgeno CatÃdico Circulante (CCA) na urina. AlÃm disso, a resposta terapÃutica foi avaliada pelos mÃtodos que detectam os antÃgenos circulantes seis semanas apÃs o tratamento. O estudo foi realizado na localidade de Bananeiras, Capistrano, uma Ãrea endÃmica no Estado do CearÃ. De 297 habitantes da localidade, 285 aceitaram participar do estudo, dos quais 159 receberam o tratamento. Destes, 128 entregaram as amostras de urina e fezes requisitadas antes e apÃs o tratamento e foram avaliados pelos trÃs mÃtodos. O ensaio UCP-LF CAA detectou 44 positivos (34,4%). A tÃcnica de Kato-Katz revelou apenas duas amostras de fezes positivas (1,6%) e o POC-CCA detectou 8 positivos (6,2%). As sensibilidades dos diferentes ensaios foram determinadas contra um padrÃo ("ouro") de positividade de infecÃÃo combinado, mostrando-se maior para o ensaio UCP-LF CAA (92%), seguido pelo POC-CCA (17%), enquanto o Kato-Katz (trÃs lÃminas) teve uma sensibilidade muito baixa (4%). A maior taxa de prevalÃncia de infecÃÃes ativas encontrada foi em pessoas com idades de 30 a 39 anos. As concentraÃÃes de CAA antes do tratamento variaram de 0,16 a 61,12 pg CAA / ml de urina, havendo um decrÃscimo significativo dos nÃveis de CAA apÃs seis semanas do tratamento (Wilcoxon, P = 0,003). Dessa maneira, tendo em conta essas observaÃÃes promissoras, o UCP-LF CAA mostrou um valor potencial para a determinaÃÃo da prevalÃncia de esquistossomose mansoni em Ãreas de baixa endemicidade; contudo, outros estudos mais amplos sÃo necessÃrios.
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Slimani, Oukacha. "Etude de l'adsorption des molécules OCS et CS dans les zéolites NaA, NaCaA et CaA détermination des isothermes et chaleurs d'adsorption par spectroscopie infrarouge /." Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb37609974k.
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Šálený, Vratislav. "Numerická simulace hluku generovaného nestabilitami ve smykové vrstvě." Doctoral thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2018. http://www.nusl.cz/ntk/nusl-383530.
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Predicting and inhibiting aerodynamically generated noise for fast moving vehicles such as cars, aircraft and trains is increasingly important. The tonal noise generated by the shear-layer instability of air flowing around the cavity opening is especially one of the most significant and most intense sources of aerodynamically generated noise. Computational aeroacoustics (CAA) based on the CFD simulations of compressible Navier-Stokes equations offers the most general approach to predicting those aerodynamically induced sounds. Aeroacoustics is practically always associated with turbulent flow and turbulence is the major challenge for CFD simulations. Four different turbulence modelling approaches are examined in this work. Three of them belong to the LES method category and one uses the URANS approach. Appropriate numerical discretization and iteration schemes have been identified for each of these approaches and implemented in the OpenFOAM open source CFD platform. The accuracy, computational performance and convergence reliability of those schemes have been subsequently studied during three-dimensional CFD simulations on a model of a suitable real object. The CFD simulation results are validated by a measurement. An organ pipe has been chosen as the object of this CAA research because it uses self-sustained oscillations, commonly referred as shear-layer (Rossiter) modes, as the source of its tone generation. The numerical simulation of the shear layer modes, respectively the noise generated by instability in the shear layer, is the subject of this work.
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Slimani, Oukacha. "Etude de l'adsorption des molecules ocs et cs::(2) dans les zeolites naa, nacaa et caa : determination des isothermes et chaleurs d'adsorption par spectroscopie infrarouge." Paris 6, 1987. http://www.theses.fr/1987PA066028.
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Chaudhari, Sachin B. "DEVELOPMENT OF AN INTERNET-BASED ANALYSIS TOOL USING THE BOUNDARY ELEMENT METHOD." University of Cincinnati / OhioLINK, 2000. http://rave.ohiolink.edu/etdc/view?acc_num=ucin971963697.
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Nassisi, Riccardo. "DAAC Messaggistica istantanea per dispositivi mobili tramite la Comunicazione Aumentativa Alternativa." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2022.
Find full textAbstract:
DAAC (Dialog with Augmentative and Alternative Communication) è una applicazione di messaggistica istantanea, sviluppata per dispositivi mobili. L’obiettivo che si pone è quello di permettere la comunicazione tra persone capaci di utilizzare il linguaggio formale basato sull’alfabeto, e persone che, a causa di condizioni di disabilità, evolutiva o temporanea, ricorrono alla Comunicazione Aumentativa e Alternativa (CAA).
L’applicazione fornisce due modalità di inserimento dei messaggi: la tastiera integrata standard del dispositivo su cui è in esecuzione l’applicazione, e l’implementazione di una tastiera pittografica basata sulla CAA; quest’ultima è composta da simboli appartenenti al sistema pittografico ARASAAC, sistema gratuito, open-source, fornito dal Governo dell’Aragona.
In base al tipo di input che viene usato, DAAC ha il compito di tradurre il messaggio digitato da testo alfabetico a serie di pittogrammi o viceversa, per permettere uno scambio di messaggi completo, a prescindere dalle capacità comunicative di chi si trova ad utilizzare l’applicazione. Tutti i messaggi visibili a schermo sono anch’essi visibili sia sotto forma di testo alfabetico che di pittogrammi.
L’obiettivo del progetto è di creare una base per lo sviluppo di soluzioni capaci di unire strumenti tecnologici all’avanguardia, ormai parte della vita quotidiana della maggior parte della società, con le tecnologie e gli strumenti che la CAA offre a chi necessita sostegni comunicativi per potersi esprimere, di fatto aumentando l’inclusione sociale dell’avanzamento tecnologico.
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Karlsson, Catarina. "Användaranpassning av instruktioner." Thesis, University of Skövde, School of Humanities and Informatics, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-2955.
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Detta arbete har syftat till att ta reda på vad som är viktigt att tänka på vid utformning av instruktioner för CAD-användare. Som praktikfall har en studie gjorts på Volvo IT där deras instruktioner för CAD/CAM/CAE-systemet CATIA V5 har granskats. Undersökningen mynnade ut i en användarstudie där erfarna användare av systemet fick möjlighet att diskutera den support som finns i dagsläget samt ställa krav på framtida instruktioner. Kraven som togs fram har legat till grund för riktlinjer för hur morgondagens instruktioner skulle kunna göras mer användaranpassade.
Några områden som är viktiga att ta hänsyn till är bland annat: att ta tillvara på användarnas erfarenhet, involvera användarna vid framtagandet av instruktionerna, ta reda på hur instruktionenrna läses samt skapa rubrikter som underlättar informationssökning för användarna.
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Paul, Steffen. "Spritzgußsimulation als Kopplungselement von CAD und CAE." Universitätsbibliothek Chemnitz, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-142037.
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Böhme, Carsten, and Klaus Brökel. "Konzept zum Parameteraustausch zwischen unterschiedlichen CAD/CAE-Plattformen." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-228848.
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Einleitung und Motivation
Im ZIM-Projekt Vestainnen wird die Entwicklung einer stationären Wirbelschichtfeuerungsanlage (SWSF) kleiner Leistung fortgesetzt. Dabei liegen die Schwerpunkte auf der Modellierung und Simulation der Belastungen an Anlage und den Abläufen in der Feuerung.
Insgesamt sind am Projekt sieben Partner beteiligt, die parallel und weitgehend unabhängig arbeiten und die Entwicklung ihres Teilprojekts vorantreiben. Bedingt durch die Vielfalt der Aufgaben kommt bei jedem Partner eine eigene, für die Teilaufgabe geeignete Softwarelösung zum Einsatz. Um die Entwicklungsergebnisse jedoch gemeinsam nutzen zu können, müssen diese eigenständigen Teilmodelle jederzeit auf einen gemeinsamen Stand gebracht werden können, um dieselbe Baugröße und Konfiguration der SWSF abzubilden.
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Böhme, Carsten, and Klaus Brökel. "Konzept zum Parameteraustausch zwischen unterschiedlichen CAD/CAE-Plattformen." TUDpress - Verlag der Wissenschaften GmbH, 2012. https://tud.qucosa.de/id/qucosa%3A30535.
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Einleitung und Motivation
Im ZIM-Projekt Vestainnen wird die Entwicklung einer stationären Wirbelschichtfeuerungsanlage (SWSF) kleiner Leistung fortgesetzt. Dabei liegen die Schwerpunkte auf der Modellierung und Simulation der Belastungen an Anlage und den Abläufen in der Feuerung.
Insgesamt sind am Projekt sieben Partner beteiligt, die parallel und weitgehend unabhängig arbeiten und die Entwicklung ihres Teilprojekts vorantreiben. Bedingt durch die Vielfalt der Aufgaben kommt bei jedem Partner eine eigene, für die Teilaufgabe geeignete Softwarelösung zum Einsatz. Um die Entwicklungsergebnisse jedoch gemeinsam nutzen zu können, müssen diese eigenständigen Teilmodelle jederzeit auf einen gemeinsamen Stand gebracht werden können, um dieselbe Baugröße und Konfiguration der SWSF abzubilden.
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Kapa, Lilla. "Numerical prediction of noise production and propagation." Doctoral thesis, Universite Libre de Bruxelles, 2011. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209828.
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Numerical simulation of noise production and propagation is a very complex problem. A methodology fitting for one particular problem can fail for another one. So there are no general guidelines on how to deal with such phenomena. In the present work, noise propagated in non-uniform mean-flow is considered. For most cases, in the propagation field, there is a rather significant region where the mean flow is not uniform, but the sound production is negligible compared to the noise emitted by the source region. In thisnearfield, a linear set of propagation equations may be considered (LEE). For such problems, the following simulation methodology is proposed:
1. Incompressible/compressible LES simulation in the source region.
2. Linearized Euler Equations to propagate the noise through the nonlinear mean flow.
3. Kirchhoff method in the farfield, if necessary.
This thesis deals with the second item of this system (LEE), including interfacing with the other two steps.
Doctorat en Sciences de l'ingénieur
info:eu-repo/semantics/nonPublished
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FABRIZI, CARLO. "Analisi computazionale dell’aeroacustica di un pneumatico in rotolamento." Doctoral thesis, Università degli Studi di Roma "Tor Vergata", 2010. http://hdl.handle.net/2108/1369.
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Il traffico stradale è una delle maggiori fonti di inquinamento acustico della società moderna. Conseguentemente, lo sviluppo dei nuovi veicoli è soggetta a direttive sempre più stringenti in termini di emissione rumorosa. Le maggiori sorgenti di rumore dei comuni veicoli stradali sono il rumore del motore, quello della trasmissione, il rumore aerodinamico e quello dell’interazione pneumatico-strada. Quest’ultimo diventa dominante tra i 50 e 100 km/h, velocità tipiche dei tratti urbani ed extra-urbani. Il rumore derivante dall’interazione pneumatico-strada è la combinazione di vibrazioni strutturali e fenomeni aeroacustici che generano e amplificano/riducono il suono emesso dal pneumatico. L’analisi numerica presentata in questa tesi ha lo scopo di investigare i meccanismi di generazione del rumore aeroacustico del pneumatico e allo stesso tempo fornire uno strumento di sviluppo di coperture a basso impatto acustico.
Il presente lavoro è diviso in due parti, l’analisi dell’aerodinamica stazionaria e l’analisi aeroacustica del pneumatico in rotolamento. Nella prima, lo studio della soluzione numerica delle Navier-Stokes mediate ha consentito di evidenziare i fenomeni aerodinamici, come separazioni o flussi a getto, che possono originare emissione acustica. Nella seconda parte tali aspetti sono stati analizzati con maggiore dettaglio per mezzo delle analogie aeroacustiche, definendo la reale capacità di predizione dello strumento numerico e fornendo suggerimenti per lo sviluppo di pneumatici più silenziosi.Road traffic is one of the major source of noise in modern society. Consequently, the development of new vehicles is subject to increasingly stringent guidelines in terms of noise emissions. The main noise sources of common road vehicles are the engine, the transmission, the aerodynamic and the tire-road interaction. The latter becomes dominant between 50 and 100 mph, speeds typical of urban and extra-urban roads. The noise that arises from tire-road is the combination of structural vibration and aeroacoustics phenomena that create and amplification/reduction of the sound emitted from the tire. The aim of the numerical analysis presented in this thesis is to investigate the aeroacoustic noise generation mechanisms of the tire and at the same time provide a tool to develop low noise tire. The present work is divided into two parts, the analysis of the steady aerodynamics and the aeroacoustic of the rolling tire. In the first part, the study of the Navier-Stokes numerical solution made it possible to highlight the aerodynamic phenomena, such as separations or jet streams, which can cause noise. In the second part these aspects have been analyzed in greater detail by means of aeroacoustic analogies, defining the capacity of the numerical tool to provide suggestions for the development of quieter tires.