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Turbulence dans l'espace de Fourier: mesures de vorticité par diffusion acoustiquepoulain, cédric 05 September 2003 (has links) (PDF)
Turbulence dans l'espace de Fourier, Mesures de vorticit´e par diffusion acoustique Resume Cette these porte sur l'etude experimentale de la vorticite en turbulence developpee dans l'espace de Fourier. Des mesures par diffusion acoustique d'ondes ultrasonores ont ete realisees d'une part dans un jet d'air ambiant en laboratoire (LEGI- Grenoble), d'autre part dans de l'Helium gazeux a 4 Kelvin au CERN (Geneve) permettant de couvrir une gamme de nombres de Reynolds (fondes sur l'echelle de Taylor) compris entre 400 et 6000. Dans un premier temps, on qualifie la chaine de mesure acoustique en comparant des experiences controlees a des calculs numeriques. On examine en particulier l'importance des effets de diffraction induits par des emetteurs de taille finie. L'utilisation de cette chaine acoustique pour l'etude de la vorticite en turbulence developpee a conduit `a deux resultats majeurs. Le premier concerne les temps caracteristiques des evenements vorticitaires turbulents. En particulier, l'etude des temps de d´ecorrelation d'un mode de Fourier de la vorticite revele l existence de deux temps caracterisant ces “evenements vorticitaires” : un temps court proportionnel au temps de “sweeping” et un temps long proportionnel au temps integral de la turbulence. De plus, une technique d'interferometrie appuyee par une analyse temps-frequence (de type Wigner-Ville) du signal complexe de diffusion suggere que le temps long traduit les interactions non-locales et le temps court les interactions locales (en Fourier). Le second resultat majeur est relatif a l'intermittence d'un point de vue spectral que nous avons analysee notamment via l'etude des densites de probabilite du signal. On montre en particulier que les modes de Fourier presentent une forte intermittence, laquelle s'accentue aux grands nombres d'onde et a grand Reynolds. La plupart de ces resultats experimentaux sont egalement observes dans des simulations numeriques directes (DNS) pseudo-spectrales du champ de vorticite correspondant a des nombres de Reynolds de l'ordre de 80.
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When graph meets diagonal: an approximative access to fixed point theory / Wenn der Graph auf die Diagonale trifft: ein approximativer Zugang zur FixpunkttheorieOkon, Thomas 25 August 2001 (has links) (PDF)
The thesis deals with a general access to topological transversality in uniform spaces. / Die Arbeit behandelt einen allgemeinen Zugang zur Topologischen Transversalität in uniformen Räumen.
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When graph meets diagonal: an approximative access to fixed point theoryOkon, Thomas 30 August 2001 (has links)
The thesis deals with a general access to topological transversality in uniform spaces. / Die Arbeit behandelt einen allgemeinen Zugang zur Topologischen Transversalität in uniformen Räumen.
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Fast Sweeping Methods for Steady State Hyperbolic Conservation Problems and Numerical Applications for Shape Optimization and Computational Cell BiologyChen, Weitao 08 August 2013 (has links)
No description available.
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Avaliação dos fatores de risco no processamento de café verde para o aparecimento de ocratoxina A (OTA) / Evaluation of risk factors in green coffee processing for ochratoxin A (OTA)Nogueira, Márcia Dimov 03 April 2007 (has links)
Dentre os perigos relacionados com a produção de café verde, a ocratoxina A (OTA) é considerada significativa nesse produto. Com o objetivo de estudar a origem da OTA no processamento de café verde e avaliar os possíveis fatores de risco (região, etapas do processamento, fungos, insetos e ácaros) que poderiam contribuir na presença de OTA, foram amostradas três fazendas nos seguintes municípios: Bom Jardim (RJ), Espírito Santo do Pinhal (SP) e Cornélio Procópio (PR), onde havia a produção de café verde pela via seca e úmida. Foram coletadas 109 amostras de grãos de café, em diversas etapas do processamento, no período de maio a agosto de 2002. As amostras foram colhidas de acordo com fluxograma estabelecido e as etapas estudadas foram: cereja (campo), via seca, via úmida, armazém e café de varrição. Dessas amostras, 10 apresentaram OTA, que variou na sua quantificação de 3 a 101 ng.g-1. A maior prevalência de OTA foi a do café de varrição 57%, a via úmida apresentou uma prevalência de 10,3% e a via seca 7%. Na etapa cereja o fungo potencialmente toxigênico mais encontrado foi Penicillium spp, e quanto aos insetos, as larvas de Diptera e os Homoptera; na via úmida foram encontradas linhagens do Aspergillus seção Nigri e Circundatti e Penicillium spp, a infestação predominante foi a broca do café e os ácaros da família Acaridae; na etapa via seca registrou-se o isolamento de fungos do gênero Penicillium spp e Aspergillus seção Nigri , a broca do café foi a infestação predominante junto com os ácaros da família Acaridae, na etapa de armazém foram isolados Penicillium spp e Aspergillus seção Nigri, o inseto predominante foi a broca do café e os ácaros da família Acaridae; no café de varrição foram isolados Penicillium spp e Aspergillus seção Nigri e a broca do café estava presente junto com insetos da Ordem Diptera. Os resultados de cada etapa foram comparados por Análise de Variância em um nível de significância de 95%. Na análise de fatores de risco o café de varrição foi o mais significativo (p< 0,001). / The ochratoxin A (OTA) is considered to be among the most significant coffee contaminants with related hazards. With the purpose to study the origin of the OTA in the processing of green coffee and to evaluate the possible risk factors (region, step of processing, fungi, insects and mites) that could contribute in the OTA presence, had been selected three regions (states) of Brazil: Bom Jardim/RJ, Espírito Santo do Pinhal/SP and Cornélio Procópio/PR. A total of 109 samples of coffee beans were collected in conformity with flow chart established at different stages of ripening and processing: cherry (field), dry method, wet method, and warehouse and varrição coffee, from May to August of 2002. Of these samples 10 had presented OTA, which varied in its quantification from 3 to 101 ng.g-1. The biggest prevalence of OTA was the varrição coffee 57%, the wet method presented a prevalence of 10,3% and dry way 7%. In the stage cherry fungi potentially toxigenic was more found Penicillium spp, the insects had been the larvae of Diptera and the Homoptera; in the wet way it was found Aspergillus section Nigri and Circundatti and Penicillium spp, the predominant infestation was the coffee berry borer and the mite of the Acaridae family; in the stage wet methods spp was registered the isolation the Penicillium spp and Aspergillus section Nigri, the predominant infestation was the coffee berry borer together with the mites of the Acaridae family; in the stage of warehouse had been isolated Penicillium spp and Aspergillus section Nigri, and the predominant insect was the coffee berry borer and mites of the family Acaridae; in the varrição coffee had been isolated Penicillium spp and Aspergillus section Nigri the coffee berry borer was the most present insects together of Diptera. The results of each step had been with compared by Analysis of Variance. In the analysis of risk factors the varrição coffee\" was the factor most strongly related to the risk of the presence of OTA (p<0,001 ).
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Avaliação dos fatores de risco no processamento de café verde para o aparecimento de ocratoxina A (OTA) / Evaluation of risk factors in green coffee processing for ochratoxin A (OTA)Márcia Dimov Nogueira 03 April 2007 (has links)
Dentre os perigos relacionados com a produção de café verde, a ocratoxina A (OTA) é considerada significativa nesse produto. Com o objetivo de estudar a origem da OTA no processamento de café verde e avaliar os possíveis fatores de risco (região, etapas do processamento, fungos, insetos e ácaros) que poderiam contribuir na presença de OTA, foram amostradas três fazendas nos seguintes municípios: Bom Jardim (RJ), Espírito Santo do Pinhal (SP) e Cornélio Procópio (PR), onde havia a produção de café verde pela via seca e úmida. Foram coletadas 109 amostras de grãos de café, em diversas etapas do processamento, no período de maio a agosto de 2002. As amostras foram colhidas de acordo com fluxograma estabelecido e as etapas estudadas foram: cereja (campo), via seca, via úmida, armazém e café de varrição. Dessas amostras, 10 apresentaram OTA, que variou na sua quantificação de 3 a 101 ng.g-1. A maior prevalência de OTA foi a do café de varrição 57%, a via úmida apresentou uma prevalência de 10,3% e a via seca 7%. Na etapa cereja o fungo potencialmente toxigênico mais encontrado foi Penicillium spp, e quanto aos insetos, as larvas de Diptera e os Homoptera; na via úmida foram encontradas linhagens do Aspergillus seção Nigri e Circundatti e Penicillium spp, a infestação predominante foi a broca do café e os ácaros da família Acaridae; na etapa via seca registrou-se o isolamento de fungos do gênero Penicillium spp e Aspergillus seção Nigri , a broca do café foi a infestação predominante junto com os ácaros da família Acaridae, na etapa de armazém foram isolados Penicillium spp e Aspergillus seção Nigri, o inseto predominante foi a broca do café e os ácaros da família Acaridae; no café de varrição foram isolados Penicillium spp e Aspergillus seção Nigri e a broca do café estava presente junto com insetos da Ordem Diptera. Os resultados de cada etapa foram comparados por Análise de Variância em um nível de significância de 95%. Na análise de fatores de risco o café de varrição foi o mais significativo (p< 0,001). / The ochratoxin A (OTA) is considered to be among the most significant coffee contaminants with related hazards. With the purpose to study the origin of the OTA in the processing of green coffee and to evaluate the possible risk factors (region, step of processing, fungi, insects and mites) that could contribute in the OTA presence, had been selected three regions (states) of Brazil: Bom Jardim/RJ, Espírito Santo do Pinhal/SP and Cornélio Procópio/PR. A total of 109 samples of coffee beans were collected in conformity with flow chart established at different stages of ripening and processing: cherry (field), dry method, wet method, and warehouse and varrição coffee, from May to August of 2002. Of these samples 10 had presented OTA, which varied in its quantification from 3 to 101 ng.g-1. The biggest prevalence of OTA was the varrição coffee 57%, the wet method presented a prevalence of 10,3% and dry way 7%. In the stage cherry fungi potentially toxigenic was more found Penicillium spp, the insects had been the larvae of Diptera and the Homoptera; in the wet way it was found Aspergillus section Nigri and Circundatti and Penicillium spp, the predominant infestation was the coffee berry borer and the mite of the Acaridae family; in the stage wet methods spp was registered the isolation the Penicillium spp and Aspergillus section Nigri, the predominant infestation was the coffee berry borer together with the mites of the Acaridae family; in the stage of warehouse had been isolated Penicillium spp and Aspergillus section Nigri, and the predominant insect was the coffee berry borer and mites of the family Acaridae; in the varrição coffee had been isolated Penicillium spp and Aspergillus section Nigri the coffee berry borer was the most present insects together of Diptera. The results of each step had been with compared by Analysis of Variance. In the analysis of risk factors the varrição coffee\" was the factor most strongly related to the risk of the presence of OTA (p<0,001 ).
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Kulturně společenské centrum u brněnské přehrady - architektonická studie objektů pro kulturně společenské i sportovní akce / The cultural and community centre near the Brno dam - the architectural design of buildings for cultural and social and sports eventsŠmihula, Michal January 2010 (has links)
The design of cultural centre is situated in part Kozia Hôrka( well-known city swimming pool), in its advantage takes natural scenery and calm atmosphere of place. Into action of performance brings a message in form of body of reservoir, function of centre is divided into small parts placed in area Kozia Hôrka. Orientation of objects comes mainly from local natural ispirations. Complex is multifunctional in concept, counts with several sorts of culture - sports events. Whereby the main function of swimming pool is preserved and added for higher comfort of inhabitants. Architecture of objects comes from idea of floating leaf on water level and body of reservoir. Objects stylizely illustrate this idea. The design takes the game of solids of organic and strictly ortogonal shapes. Two mutual opposites, in interaction. Objects smoothy and with respect encroach the environment, which is enough marked by human. Simplicity in used materials ( glass, steel, wood ) give transparency and purity to whole solution.
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