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Monitoring fluidized bed dryer hydrodynamics using pressure fluctuations and electrical capacitance tomographyChaplin, Gareth Edgar 24 March 2005 (has links)
As part of the production of certain solid-dosage pharmaceuticals, granulated ingredients are dried in a batch fluidized bed dryer. Currently, the determination of the completion of the drying process is accomplished through measurements of product or outlet air temperatures. No quantitative measurement of hydrodynamic behaviour is employed. Changes in bed hydrodynamics caused by variations in fluidization velocity may lead to increased particle attrition. In addition, excessive desiccation of the granules caused by inaccurate determination of the drying endpoint may lead to an increase in the thermal and mechanical stresses within the granules. The activity of future high-potency or peptide based drug products may be influenced by these effects. Therefore, the quantification of hydrodynamic changes may be a key factor in the tighter control of both fluidization velocity and product moisture, which are critical for maintaining product quality. <p>High-frequency measurements of pressure fluctuations in a batch fluidized bed dryer containing pharmaceutical granulate have been used to provide a global, non-intrusive indication of the hydrodynamic changes occurring throughout the drying process. A chaotic attractor comparison statistical test known as the S-statistic, has been applied to quantify these changes in drying and a related unit operation, fluidized bed granulation. The S-statistic showed a sensitivity to moisture which is not seen with frequency and amplitude analysis. In addition, the S-statistic has been shown to be useful in identifying an undesirable bed state associated with the onset of entrainment in a bed instrumented for the collection of both pressure fluctuation and entrainment data. Thus, the use of the S-statistic analysis of pressure fluctuations may be utilized as a low-cost method for determining product moisture or changes hydrodynamic state during fluidized bed drying. <p>Electrical capacitance tomography (ECT) has also been applied in this study to image the flow structure within a batch fluidized bed used for the drying of pharmaceutical granulate. This represents the first time that ECT has been applied to a bed of wet granulate material. This was accomplished through the use of a novel dynamic correction technique which accounts for the significant reduction in electrical permittivity occurring as moisture is lost during the drying process. The correction has been independently verified using x-ray tomography. <p>Investigation of the ECT images taken in the drying bed indicates centralized bubbling behaviour for approximately the first 5 minutes of drying. This behaviour is a result of the high liquid loading of the particles at high moisture. Between moisture contents of 18-wt% and 10-wt%, the tomograms show an annular pattern of bubbling behaviour with a gradual decrease in the cross-sectional area involved in bubbling behaviour. The dynamic analysis of this voidage data with the S-statistic showed that a statistically significant change occurs during this period near the walls of the vessel, while the centre exhibits less variation in dynamic behaviour. The changes identified by the S-statistic analysis of voidage fluctuations near the wall were similar to those seen in the pressure fluctuation measurements. This indicates that the source of the changes identified by both these measurement techniques is a result of the reduction in the fraction of the bed cross-section involved in bubbling behaviour. At bed moisture contents below 5-wt%, rapid divergence was seen in the S-statistic applied to both ECT and pressure fluctuation measurements. This indicates that a rapid change in dynamics occurs near the end of the drying process. This is possibly caused by the entrainment of fines at this time, or the build-up of electrostatic charge. <p>The use of the complimentary pressure fluctuation and ECT measurement techniques have identified changes occurring as a result of the reduction of moisture during the drying process. Both the localized changes in the voidage fluctuations provided by the ECT imaging and the global changes shown by the pressure fluctuation measurements indicate significant changes in the dynamic behaviour caused by the reduction of moisture during the drying process. These measurement techniques could be utilized to provide an on-line indication of changes in hydrodynamic regime. This information may be invaluable for the future optimization of the batch drying process and accurate determination of the drying endpoint.
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QP Partitioning for Radiationless TransitionsLavigne, Cyrille 18 March 2014 (has links)
This work presents a new implementation of the QP algorithm, a computer method to diagonalize the extremely large matrices arising in multimode vibronic problems. Benchmark calculations are included, showing the accuracy of the program. The QP algorithm is extended to treat multiple electronic surfaces for competitive control and this is demonstrated with an Hamiltonian including three electronic states, a model of the benzene radical cation. Finally, the evolution of zeroth-order states in a simple two electronic states, two dimensional model with a conical intersection is explored, towards building a time-dependent view of overlapping resonances coherent control.
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QP Partitioning for Radiationless TransitionsLavigne, Cyrille 18 March 2014 (has links)
This work presents a new implementation of the QP algorithm, a computer method to diagonalize the extremely large matrices arising in multimode vibronic problems. Benchmark calculations are included, showing the accuracy of the program. The QP algorithm is extended to treat multiple electronic surfaces for competitive control and this is demonstrated with an Hamiltonian including three electronic states, a model of the benzene radical cation. Finally, the evolution of zeroth-order states in a simple two electronic states, two dimensional model with a conical intersection is explored, towards building a time-dependent view of overlapping resonances coherent control.
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Determinação do coeficiente de atrito para as ligas de alumínio AA6351e e de titânio Ti6Al4V pelos métodos do anel e tubo cônicoBueno, Alex Fabiano January 2010 (has links)
O presente trabalho apresenta um breve apanhado do processo de forjamento, resultados da investigação experimental e da análise computacional acerca do teste de compressão do anel e ensaio do tubo cônico, ambos visando a determinação do coeficiente de atrito existente na região de contato entre as matrizes e os corpos-de-prova, para as ligas de alumínio AA6351 e de titânio Ti6Al4V. Foram realizadas curvas teóricas de calibração do coeficiente de atrito tanto para o alumínio quanto para o titânio com faixa de temperatura distinta para cada um dos materiais. Após a realização da calibração por meio das curvas foram realizados os ensaios práticos de compressão do anel e do tubo cônico, também foram realizadas as simulações computacionais dos ensaios do tubo. Estas simulações permitiram a verificação teórica do fluxo de material no interior dos corpos de prova comparando-as com o material obtido em ensaios práticos, comprovando a eficiência dos programas de simulação, visto que a geometria do tubo favorece a comparação entre a simulação e os testes experimentais. Os resultados obtidos tanto nos experimentos teóricos como os práticos, efetuou-se uma comparação com os dados das referências bibliográficas descritas neste trabalho. Em que os dois lubrificantes testados apresentaram desempenho satisfatório, devido à redução do contato interfacial da relação matriz/peça. E o ensaio do tubo cônico mostrou-se viável apenas para determinação a quente do coeficiente de atrito, neste caso o comportamento em ambos os ensaios é similar. / This paper presents a brief overview of the forging process and the results of experimental investigation and computational analysis of ring compression testing and conical tube-upsetting test, both aiming to determine the coefficient of friction in the region of contact between die and bodies-of-evidence for the AA6351 aluminum alloy and titanium Ti6Al4V. Theoretical calibration through curves were performed of the coefficient of friction were performed for both aluminum and titanium with different temperature range for each material. After completion of the calibration curves compression ring and the conical tube practical tests were performed, computer simulations of the tube-upsetting test were also performed. Continue) These simulations allowed to verify the theoretical flow of material within the samples and comparing them with the material obtained in practical tests, proving the efficiency of simulation programs, since the geometry of the tube facilitates the comparison between the simulation and testing experiments. The results in both theoretical and practical experiments, were a compared with the data from the references described herein. Two oils tested showed a satisfactory performance due to the reduced interfacial contact relationship die/workpiece. And the tube-upsetting test was feasible only to determine the hot coefficient of friction, in this case the behavior in both tests is similar.
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Determinação do coeficiente de atrito para as ligas de alumínio AA6351e e de titânio Ti6Al4V pelos métodos do anel e tubo cônicoBueno, Alex Fabiano January 2010 (has links)
O presente trabalho apresenta um breve apanhado do processo de forjamento, resultados da investigação experimental e da análise computacional acerca do teste de compressão do anel e ensaio do tubo cônico, ambos visando a determinação do coeficiente de atrito existente na região de contato entre as matrizes e os corpos-de-prova, para as ligas de alumínio AA6351 e de titânio Ti6Al4V. Foram realizadas curvas teóricas de calibração do coeficiente de atrito tanto para o alumínio quanto para o titânio com faixa de temperatura distinta para cada um dos materiais. Após a realização da calibração por meio das curvas foram realizados os ensaios práticos de compressão do anel e do tubo cônico, também foram realizadas as simulações computacionais dos ensaios do tubo. Estas simulações permitiram a verificação teórica do fluxo de material no interior dos corpos de prova comparando-as com o material obtido em ensaios práticos, comprovando a eficiência dos programas de simulação, visto que a geometria do tubo favorece a comparação entre a simulação e os testes experimentais. Os resultados obtidos tanto nos experimentos teóricos como os práticos, efetuou-se uma comparação com os dados das referências bibliográficas descritas neste trabalho. Em que os dois lubrificantes testados apresentaram desempenho satisfatório, devido à redução do contato interfacial da relação matriz/peça. E o ensaio do tubo cônico mostrou-se viável apenas para determinação a quente do coeficiente de atrito, neste caso o comportamento em ambos os ensaios é similar. / This paper presents a brief overview of the forging process and the results of experimental investigation and computational analysis of ring compression testing and conical tube-upsetting test, both aiming to determine the coefficient of friction in the region of contact between die and bodies-of-evidence for the AA6351 aluminum alloy and titanium Ti6Al4V. Theoretical calibration through curves were performed of the coefficient of friction were performed for both aluminum and titanium with different temperature range for each material. After completion of the calibration curves compression ring and the conical tube practical tests were performed, computer simulations of the tube-upsetting test were also performed. Continue) These simulations allowed to verify the theoretical flow of material within the samples and comparing them with the material obtained in practical tests, proving the efficiency of simulation programs, since the geometry of the tube facilitates the comparison between the simulation and testing experiments. The results in both theoretical and practical experiments, were a compared with the data from the references described herein. Two oils tested showed a satisfactory performance due to the reduced interfacial contact relationship die/workpiece. And the tube-upsetting test was feasible only to determine the hot coefficient of friction, in this case the behavior in both tests is similar.
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Gain and Loss Factor for Conical Horns, and Impact of Ground Plane Edge Diffractions on Radiation Patterns of Uncoated and Coated Circular Aperture AntennasJanuary 2014 (has links)
abstract: Horn antennas have been used for over a hundred years. They have a wide variety of uses where they are a basic and popular microwave antenna for many practical applications, such as feed elements for communication reflector dishes on satellite or point-to-point relay antennas. They are also widely utilized as gain standards for calibration and gain measurement of other antennas.
The gain and loss factor of conical horns are revisited in this dissertation based on
spherical and quadratic aperture phase distributions. The gain is compared with published classical data in an attempt to confirm their validity and accuracy and to determine whether they were derived based on spherical or quadratic aperture phase distributions. In this work, it is demonstrated that the gain of a conical horn antenna obtained by using a spherical phase distribution is in close agreement with published classical data. Moreover, more accurate expressions for the loss factor, to account for amplitude and phase tapers over the horn aperture, are derived. New formulas for the design of optimum gain conical horns, based on the more accurate spherical aperture phase distribution, are derived.
To better understand the impact of edge diffractions on aperture antenna performance, an extensive investigation of the edge diffractions impact is undertaken in this dissertation for commercial aperture antennas. The impact of finite uncoated and coated PEC ground plane edge diffractions on the amplitude patterns in the principal planes of circular apertures is intensively examined. Similarly, aperture edge diffractions of aperture antennas without ground planes are examined. Computational results obtained by the analytical model are compared with experimental and HFSS-simulated results for all cases studied. In addition, the impact of the ground plane size, coating thickness, and relative permittivity of the dielectric layer on the radiation amplitude in the back region has been examined.
This investigation indicates that the edge diffractions do impact the main forward lobe pattern, especially in the E plane. Their most significant contribution appears in far side and back lobes. This work demonstrates that the finite edge contributors must be considered to obtain more accurate amplitude patterns of aperture antennas. / Dissertation/Thesis / Doctoral Dissertation Electrical Engineering 2014
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A utilização do software GeoGebra no ensino da geometria analíticaBrito, Marcos Alves de 19 December 2014 (has links)
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Previous issue date: 2014-12-19 / Outra / In this thesis we aim, through the use of a technological tool, the
computer, show the possibility of teaching Mathematics causing the student to build
their knowledge from concepts presented with the help of software that allow viewing
the activities developed. In this sense, we use the GeoGebra software, it is a
dynamic geometry software in the public domain and its application to analytic
geometry content is easy to learn for the user. Thus, we present a teaching sequence
using GeoGebra software in teaching Analytic Geometry, following the contents of the
Curriculum Proposal of the State of São Paulo. In each of the proposed activities
develop the theoretical content with exercises followed by activity in GeoGebra. At
the end of each activity are some of the comments made by students. / Nesta dissertação temos como objetivo, a partir do uso de uma ferramenta
tecnológica, o computador, mostrar a possibilidade de ensinar Matemática fazendo com
que o estudante construa seu conhecimento a partir de conceitos apresentados com
auxílio de softwares que possibilitem visualizar as atividades desenvolvidas. Neste
sentido, utilizamos o software GeoGebra, que se trata de um software de Geometria
dinâmica de domínio público e sua aplicação aos conteúdos de Geometria Analítica é de
fácil aprendizado para o usuário. Desta forma, apresentamos uma sequência didática
utilizando o Software GeoGebra no ensino de Geometria Analítica, seguindo os conteúdos
da Proposta Curricular do Estado de São Paulo. Em cada uma das atividades propostas
desenvolvemos o conteúdo teórico com exercícios seguido da atividade no GeoGebra. Ao
final de cada atividade apresentamos alguns dos comentários feitos pelos estudantes.
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Excavations at the Templete de Limoncarro in the Lower Valley of Jequetepeque / Excavaciones en el Templete de Limoncarro, valle bajo de JequetepequeSakai, Masato, Martínez, Juan José 10 April 2018 (has links)
This is a first synopsis of the research that we have realized at the Templete de Limoncarro recognized as a site of the Cupisnique culture. At this Templete we have excavated five times and identified two phases of construction. The structures of the first phase, La Calera, are very few, while at the second phase, Limoncarro, are constructed a sunken court and three platforms, which are the objects of frequent repair. Some structures of conic adobe at the platforms represent faces of animals, which seems to be of the Cupisnique iconography. / La presente es una primera aproximación al estudio que se realiza en la actualidad en el Templete de Limoncarro, complejo reconocido como un sitio de la cultura Cupisnique. En este se han efectuado excavaciones a lo largo de cinco temporadas y se ha comprobado la existencia de dos fases de construcción. Las edificaciones de la primera fase, denominada La Calera, son muy escasas, en tanto que a la segunda fase, nombrada como Limoncarro, corresponden la plaza hundida y las tres plataformas identificadas, las que fueron objeto de reparaciones frecuentes mientras estuvieron vigentes. Algunas de las estructuras hechas con adobes cónicos en dichas plataformas representan rostros de animales, los que se asemejan a la iconografía cupisnique.
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Determinação do coeficiente de atrito para as ligas de alumínio AA6351e e de titânio Ti6Al4V pelos métodos do anel e tubo cônicoBueno, Alex Fabiano January 2010 (has links)
O presente trabalho apresenta um breve apanhado do processo de forjamento, resultados da investigação experimental e da análise computacional acerca do teste de compressão do anel e ensaio do tubo cônico, ambos visando a determinação do coeficiente de atrito existente na região de contato entre as matrizes e os corpos-de-prova, para as ligas de alumínio AA6351 e de titânio Ti6Al4V. Foram realizadas curvas teóricas de calibração do coeficiente de atrito tanto para o alumínio quanto para o titânio com faixa de temperatura distinta para cada um dos materiais. Após a realização da calibração por meio das curvas foram realizados os ensaios práticos de compressão do anel e do tubo cônico, também foram realizadas as simulações computacionais dos ensaios do tubo. Estas simulações permitiram a verificação teórica do fluxo de material no interior dos corpos de prova comparando-as com o material obtido em ensaios práticos, comprovando a eficiência dos programas de simulação, visto que a geometria do tubo favorece a comparação entre a simulação e os testes experimentais. Os resultados obtidos tanto nos experimentos teóricos como os práticos, efetuou-se uma comparação com os dados das referências bibliográficas descritas neste trabalho. Em que os dois lubrificantes testados apresentaram desempenho satisfatório, devido à redução do contato interfacial da relação matriz/peça. E o ensaio do tubo cônico mostrou-se viável apenas para determinação a quente do coeficiente de atrito, neste caso o comportamento em ambos os ensaios é similar. / This paper presents a brief overview of the forging process and the results of experimental investigation and computational analysis of ring compression testing and conical tube-upsetting test, both aiming to determine the coefficient of friction in the region of contact between die and bodies-of-evidence for the AA6351 aluminum alloy and titanium Ti6Al4V. Theoretical calibration through curves were performed of the coefficient of friction were performed for both aluminum and titanium with different temperature range for each material. After completion of the calibration curves compression ring and the conical tube practical tests were performed, computer simulations of the tube-upsetting test were also performed. Continue) These simulations allowed to verify the theoretical flow of material within the samples and comparing them with the material obtained in practical tests, proving the efficiency of simulation programs, since the geometry of the tube facilitates the comparison between the simulation and testing experiments. The results in both theoretical and practical experiments, were a compared with the data from the references described herein. Two oils tested showed a satisfactory performance due to the reduced interfacial contact relationship die/workpiece. And the tube-upsetting test was feasible only to determine the hot coefficient of friction, in this case the behavior in both tests is similar.
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Micromorfologia de pétalas e sua relação com a polinizaçãoCOSTA, Vanessa Bastos Simões da 21 February 2014 (has links)
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Previous issue date: 2014-02-21 / The petals of many species of Angiosperms have as main function to attract pollinators, them visual, tactile and olfactory signals occur, which in most cases are associated with the anatomy of this organ, which influences the reproductive success of plants. One of the main microstructures involved in attractive feature is the presence of conical epidermal cells on the adaxial surface of petals. These cells play related to the absorption and reflection of light functions, enhancing the perceived color, in addition to being covered by a cuticle, which influences the gloss. Can also facilitate the adhesion and locomotion of the pollinator on the petal. In many cases produce odoriferous substances that attract pollinators. Another characteristic micromorphological petals with attractive function is related to the mesophyll, which according to the arrangement of its cells can increase the reflection of sunlight, and can still accumulate odoriferous substances. These characteristics of the petals may vary with the groups of pollinators. Whereas the morphology of petals can vary and influence in interactions with pollinators we aim to relate the characteristics micromorphological petals with pollination syndrome, using as a model species pollinated by bees, birds and bats. For that petals were investigated 11 species distributed in three pollination syndromes, melittophily, ornithophily and chiropterophily, with respect to several parameters; these parameters were analyzed by optical images and scanning electron microscopy. Qualitative characters were described based on the literature and quantitative traits were compared in ANOVA, Tukey test, with alpha 5%, and the variation of quantitative anatomical characters was assessed by principal component analysis (PCA), and the similarity of characters was verified by the cluster analysis (Cluster). All mellittophilous and ornithophilous species showed cone cells in the epidermal surface of the upper face, with the exception of the standard petal Periandra coccinea, with flat cells, as well as all chiropterophilous species. All species present epicuticular striations. The mesophyll of mellittophilous and ornithophilous species consisted of cells braciformes and many intercellular spaces. Cassia grandis (mellittophilous) presented sclerified pericyclic fibers in the bundle sheath of the main vein. The Pachira aquatica chiropterophilous species presented a thickened mesophyll and secretory cavities were observed in this region of the petal. In cluster analysis the chiropterophilous species split off from mellittophilous and ornithophilous species, PCA showed that the variable of greatest importance in the pool is the distance between the apexes. We can conclude that micromorphological characters analyzed did not define the pollination syndrome. Biometrics showed the closeness between species and mellittophilous ornithophilous; that the distance between the apexes in cone cells was the most important character in the grouping of species and this parameter is a mediator in the interaction with the pollinator; and the development of pericyclic fibers sclerified in the bundle sheath of the main vein of petals indicated a response of mechanical vibration resistance. / As pétalas de muitas espécies de Angiospermas têm como principal função a atração de polinizadores, nelas ocorrem sinais visuais, táteis e olfativos, que na maioria das vezes estão associados à anatomia deste órgão, que influencia no sucesso reprodutivo das plantas. Uma das principais microestruturas envolvidas na função atrativa é a presença de células epidérmicas cônicas na superfície adaxial das pétalas. Essas células desempenham funções relacionadas à absorção e reflexão da luz, intensificando a cor percebida, além de estarem recoberta por cutícula, que influencia no brilho. Também podem facilitar à aderência e locomoção do polinizador sobre a pétala. Em muitos casos produzem substâncias odoríferas, que atraem polinizadores. Outra característica micromorfológica de pétalas com função atrativa está relacionada ao mesofilo, que de acordo com a disposição de suas células podem aumentar a reflexão dos raios solares, e ainda podem acumular substâncias odoríferas. Estas características das pétalas podem variar de acordo com os grupos de polinizadores. Considerando que a micromorfologia de pétalas pode variar e influenciar nas interações com os polinizadores temos o objetivo relacionar as características micromofológicas de pétalas com a síndrome de polinização, usando como modelo espécies polinizadas por abelhas, aves e morcegos. Para isso foram investigadas pétalas de 11 espécies distribuídas em três síndromes de polinização, melitofilia, ornitofilia e quiropterofilia, com relação a vários parâmetros; estes parâmetros foram analisados através de imagens de microscopia ótica e eletrônica de varredura. Os caracteres qualitativos foram descritos com base na literatura e os caracteres quantitativos foram comparados em Anova, teste Tukey, com alfa a 5%, e a variação dos caracteres anatômicos quantitativos foi avaliada por meio da análise de componentes principais (PCA), e a similaridade dos caracteres foi verificada por meio da análise de agrupamento (Cluster). Todas as espécies melitófilas e ornitófilas apresentaram células cônicas na superfície adaxial da epiderme, com exceção da pétala estandarte de Periandra coccinea, com células planas, assim como todas as espécies quiropterófilas. Todas as espécies analisadas apresentam estriações epicuticulares. O mesofilo das espécies melitófilas e ornitófilas foram constituídos de células braciformes e muitos espaços intercelulares. Cassia grandis (melitófila) apresentou fibras pericíclicas esclerificadas na bainha do feixe da nervura principal. A espécie quiropterófila Pachira aquatica apresentou um mesofilo espessado, e foi observado cavidades secretoras nesta região da pétala. Na análise de agrupamento as espécies quiropterófilas se separam das espécies melitófilas e ornitófilas, o PCA mostrou que a variável com maior importância no agrupamento é a distância entre os ápices. Podemos concluir que os caracteres micromorfológicos analisados não definiram as síndromes de polinização. A biometria mostrou a aproximação entre espécies melitófilas e ornitófilas; que a distância entre os ápices em células cônicas foi o caractere de maior importância no agrupamento das espécies e este é um parâmetro mediador na interação com o polinizador; e que o desenvolvimento de fibras pericíclicas esclerificadas na bainha do feixe da nervura principal de pétalas indicou uma resposta de resistência mecânica à vibração.
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