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Scalability of cone calorimeter test results for the prediction of full scale fire behavior of polyurethane foam2014 August 1900 (has links)
The ignition and subsequent burning of polyurethane foam based mattresses poses a significant danger to life and safety in North American homes. The development of fire models which can predict the full scale fire behavior of these mattresses using bench scale data would assist manufacturers and regulators to manage this danger in a cost effective manner. This thesis builds on previous work by the University of Saskatchewan and University of Waterloo fire research groups and focuses on the evaluation of one such scaling model, which was originally developed during the Combustion Behavior of Upholstered Furniture (CBUF) project. The evaluation of the CBUF model conducted in this thesis isolates the heat release rate (HRR) density sub-model and explores the effects of 1) cone calorimeter incident heat flux setting, 2) specimen thickness and 3) ignition location on the predictive capability of the CBUF model.
To provide input for the CBUF model cone and furniture calorimeter tests were conducted. Cone calorimeter tests were conducted on foam specimen thicknesses of 2.5, 5.0, 7.5 and 10.0 cm at incident heat flux settings of 25, 35, 50 and 75 kW/m2. Furniture calorimeter tests were conducted on foam specimen thicknesses of 2.5, 5.0, 7.5 and 10.0 cm in both edge and center ignition configuration. Flame area spread rates were measured from infrared video of the furniture calorimeter tests using an automated algorithm.
It was found that HRR curves predicted by the CBUF model showed good agreement with experimental results. Experimental results from tests of thinner foams were predicted with greater success than results from thicker foams, and results from edge ignition tests were predicted with greater success than results of center ignition tests. The results of this study indicated that specimen thickness and ignition location need to be considered when selecting an appropriate incident heat flux setting for producing input data for the CBUF model.
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Modélisation implicite par squelette et ApplicationsZanni, Cédric 06 December 2013 (has links) (PDF)
Modéliser avec des squelettes est une alternative très séduisante aux "points de contrôle" souvent placés à l'extérieur des formes : cette approche, analogue à un fil de fer dans une forme modelée, permet de créer des modèles de toutes géométries et topologies. Pour cela, il faut que les formes définies par chacun des squelettes soient capable de se mélanger de manière lisse. Introduites en informatique graphique dans les années 90, les surfaces implicites sont la principale solution à ce problème. Elles constituent un modèle puissant à la fois pour la modélisation d'objets tridimensionnels et pour leur animation: leur construction par squelette et leurs capacités de mélange par sommation des champs potentiels qui les définissent permettent en effet la conception progressive et le stockage compact d'objets volumiques, ainsi que l'animation de déformations pouvant comprendre des changements de topologie. Les surfaces implicites, et plus particulièrement les surfaces de convolution, forment donc un modèle particulièrement adapté à la modélisation par squelette. Toutefois, elles présentent un certain nombre de défaut qui les ont rendu inutilisables en pratique. Cette thèse propose de nouveaux modèles implicites à squelettes, s'inspirant de la convolution mais basés aussi sur des déformations de l'espace. Ils permettent : - une génération plus aisée de forme le long de squelettes formés de courbes (des arc d'hélices), - un meilleur contrôle des formes tant au niveau de leur épaisseur que de leur mélange, notamment - nos modèles sont invariant par homothétie ce qui les rend plus intuitif, - la génération de surfaces ayant une topologie plus proche de celle des squelettes, - la génération de détails fins engendrés par un bruit procédural, les détails se comportant de manière cohérente avec la surface (et les squelettes) sous-jacente.
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On the simulation of overhead transmission linesSilverman, Shawn F. 13 October 2005 (has links)
This thesis explores and implements techniques for frequency domain modelling and time domain simulation of overhead transmission lines. The popular Vector Fitting algorithm is employed to approximate the frequency domain model using rational functions, and the recursive convolution technique is applied to the rational approximation to generate a time domain form.
The frequency domain model is translated into the time domain using delay extraction, modal decomposition, passivity enforcement, and rational approximation. Several approaches to each of these procedures are investigated.
The thesis also discusses several choices for the integration method used within the recursive convolution procedure.
In order to make the transmission line modeller and simulator easy to use, a Java-based library and partial graphical interface were developed. Specifically, the goal was to develop a platform-independent program that can run either stand-alone or as an applet inside a web page.
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On the simulation of overhead transmission linesSilverman, Shawn F. 13 October 2005 (has links)
This thesis explores and implements techniques for frequency domain modelling and time domain simulation of overhead transmission lines. The popular Vector Fitting algorithm is employed to approximate the frequency domain model using rational functions, and the recursive convolution technique is applied to the rational approximation to generate a time domain form.
The frequency domain model is translated into the time domain using delay extraction, modal decomposition, passivity enforcement, and rational approximation. Several approaches to each of these procedures are investigated.
The thesis also discusses several choices for the integration method used within the recursive convolution procedure.
In order to make the transmission line modeller and simulator easy to use, a Java-based library and partial graphical interface were developed. Specifically, the goal was to develop a platform-independent program that can run either stand-alone or as an applet inside a web page.
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Semilinear stochastic differential equations with applications to forward interest rate models.Mark, Kevin January 2009 (has links)
In this thesis we use techniques from white noise analysis to study solutions of semilinear stochastic differential equations in a Hilbert space H: {dX[subscript]t = (AX[subscript]t + F(t,X[subscript]t)) dt + ơ(t,X[subscript]t) δB[subscript]t, t∈ (0,T], X[subscript]0 = ξ, where A is a generator of either a C[subscript]0-semigroup or an n-times integrated semigroup, and B is a cylindrical Wiener process. We then consider applications to forward interest rate models, such as in the Heath-Jarrow-Morton framework. We also reformulate a phenomenological model of the forward rate. / Thesis (Ph.D.) -- University of Adelaide, School of Mathematical Science, 2009
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Semilinear stochastic differential equations with applications to forward interest rate models.Mark, Kevin January 2009 (has links)
In this thesis we use techniques from white noise analysis to study solutions of semilinear stochastic differential equations in a Hilbert space H: {dX[subscript]t = (AX[subscript]t + F(t,X[subscript]t)) dt + ơ(t,X[subscript]t) δB[subscript]t, t∈ (0,T], X[subscript]0 = ξ, where A is a generator of either a C[subscript]0-semigroup or an n-times integrated semigroup, and B is a cylindrical Wiener process. We then consider applications to forward interest rate models, such as in the Heath-Jarrow-Morton framework. We also reformulate a phenomenological model of the forward rate. / Thesis (Ph.D.) -- University of Adelaide, School of Mathematical Science, 2009
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[en] GENERATING CAPACITY RELIABILITY EVALUATION CONSIDERING UNCERTAINTIES IN UNIT UNAVAILABILITY AND LOAD FORECASTING / [pt] AVALIAÇÃO DA CONFIABILIDADE DA CAPACIDADE DE GERAÇÃO CONSIDERANDO INCERTEZAS NA INDISPONIBILIDADE DAS UNIDADES GERADORAS E NA PREVISÃO DOS PICOS DE CARGAFLAVIO ANTONIO FARINA PAZO BLANCO 14 May 2007 (has links)
[pt] Este trabalho apresenta um método geral e prático,
baseado
em técnicas de convolução discreta, para avaliar o valor
esperado e a variância dos índices de perda de carga
associados a um sistema de geração. O método proposto
trata as indisponibilidades das unidades geradoras e os
valores estimados para os picos de carga como variáveis
aleatórias, especificadas por médias e variâncias, e
modela, sem qualquer restrição, geradores com estados de
capacidade intermediários. Também é mostrado como as
técnicas de Transformada Rápida de Fourier podem ser
aplicadas na solução deste problema.
O algoritmo proposto é aplicado a vários sistemas de
geração, incluindo o sistema teste de confiabilidade do
IEEE, e os resultados são discutidos. / [en] This work presents a pratical and general method based on
discrete convolution techniques for evaluating the
expectation and variance of the loss of load índices, for
a single-area system, by treating forced outage rates and
forecast peak loads as random variables with specified
means and variances. The proposed method easily accounts
for partial forced outage rates associated with unit
derated states, without any restrictions. Also, it is
shown how fast Fourier transtorm techniques can be used to
carry out the discrete convolution.
The proposed algorithm is applied to typical generating
systems including the IEEE Reliability Test System, and
the results are discussed.
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Big Data Analysis of Bacterial Inhibitors in Parallelized Cellomics - A Machine Learning ApproachJanuary 2016 (has links)
abstract: Identifying chemical compounds that inhibit bacterial infection has recently gained a considerable amount of attention given the increased number of highly resistant bacteria and the serious health threat it poses around the world. With the development of automated microscopy and image analysis systems, the process of identifying novel therapeutic drugs can generate an immense amount of data - easily reaching terabytes worth of information. Despite increasing the vast amount of data that is currently generated, traditional analytical methods have not increased the overall success rate of identifying active chemical compounds that eventually become novel therapeutic drugs. Moreover, multispectral imaging has become ubiquitous in drug discovery due to its ability to provide valuable information on cellular and sub-cellular processes using florescent reagents. These reagents are often costly and toxic to cells over an extended period of time causing limitations in experimental design. Thus, there is a significant need to develop a more efficient process of identifying active chemical compounds.
This dissertation introduces novel machine learning methods based on parallelized cellomics to analyze interactions between cells, bacteria, and chemical compounds while reducing the use of fluorescent reagents. Machine learning analysis using image-based high-content screening (HCS) data is compartmentalized into three primary components: (1) \textit{Image Analytics}, (2) \textit{Phenotypic Analytics}, and (3) \textit{Compound Analytics}. A novel software analytics tool called the Insights project is also introduced. The Insights project fully incorporates distributed processing, high performance computing, and database management that can rapidly and effectively utilize and store massive amounts of data generated using HCS biological assessments (bioassays). It is ideally suited for parallelized cellomics in high dimensional space.
Results demonstrate that a parallelized cellomics approach increases the quality of a bioassay while vastly decreasing the need for control data. The reduction in control data leads to less fluorescent reagent consumption. Furthermore, a novel proposed method that uses single-cell data points is proven to identify known active chemical compounds with a high degree of accuracy, despite traditional quality control measurements indicating the bioassay to be of poor quality. This, ultimately, decreases the time and resources needed in optimizing bioassays while still accurately identifying active compounds. / Dissertation/Thesis / Doctoral Dissertation Computer Science 2016
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Estudo da distribuição do tempo de residência em um processo de pasteurização assistido por micro-ondas. / Study of the residence time distribution in a pasteurization process assisted by microwaves.Nilo Henrique Meira Fortes 22 August 2018 (has links)
O processo de pasteurização tem como objetivo garantir a segurança e qualidade nutricional do alimento e aumentar sua vida de prateleira. O conhecimento da distribuição do tempo de residência (DTR) do alimento em cada etapa do processo contínuo é importante para uma avaliação adequada do processo e das alterações que causa no alimento. Este trabalho tem como objetivo estudar a DTR em um processo de pasteurização contínuo assistido por micro-ondas aplicado a alimentos líquidos e propor modelos de escoamento para representá-la. Para isso, foram realizados experimentos de estímulo-resposta com alimentação tipo pulso por técnica condutimétrica utilizando uma solução saturada de NaCl como traçador. Com isso, foram obtidas as curvas de DTR do sistema completo, dos trocadores de calor das seções de pré-aquecimento e resfriamento, de seis tubos de retenção com diferentes diâmetros e comprimentos (volumes entre 40 e 125 mL) e do sistema de aquisição de dados de condutividade elétrica. Os experimentos foram realizados em quatro vazões volumétricas (0,5, 0,7, 0,9 e 1,1 L/min), a temperatura ambiente (19 a 26 °C) e como fluido de trabalho foi utilizada uma corrente de alimentação de água com concentração 0,5 g/L de NaCl para estabilizar a leitura de condutividade elétrica. Foram realizadas três repetições por vazão para o processo completo, trocadores de calor e tubos de retenção, e cinco repetições por vazão para o sistema de aquisição de dados, dada a maior sensibilidade. Observou-se a necessidade de realizar o procedimento de convolução numérica para avaliar a distorção na curva de DTR do processo causada pelo escoamento na célula do sistema de aquisição de dados. Foram testados cinco modelos de escoamento: dispersão axial, compartimentado PFR+CSTR, tanques em série, convecção generalizada e y-laminar. O critério de ajuste dos modelos foi a minimização do erro quadrático entre valores experimentais e calculados da curva E(t). Os modelos de dispersão axial e y-laminar foram o que apresentaram melhor ajuste para os tubos de retenção e o modelo de convecção generalizada apresentou melhor ajuste para os trocadores de calor. O regime de escoamento durante os experimentos variou entre laminar e de transição (valores de Reynolds entre 1259 e 4238). Os resultados para o sistema completo e trocadores de calor foram satisfatórios, para os tubos de retenção foi observada uma grande incerteza nos valores dos parâmetros e foi observada a importância da convolução numérica em sistemas de pequeno volume. / Pasteurization process aims to ensure the safety and nutritional quality of the food and increase its shelf life. The knowledge of residence time distribution (RTD) of the food in each step of continuous processes is important to evaluate the process and changes that it causes in foods. This work aims to study the RTD in a continuous pasteurization process assisted by microwave applied to liquid foods and propose flow models to represent it. For this reason, stimulus-response experiments by pulse injection were conducted by conductimetric technique using a saturated solution of NaCl as a tracer. Thus, it was obtained the RTD of the complete process, heat exchangers of preheating section and cooling section, six retention tubes with different diameters and lengths (volumes between 40 and 125 mL) and of the electrical conductivity data acquisition system. The experiments were carried out at four volumetric flow rates (0.5, 0.7, 0.9 and 1.1 L/min), at room temperature (19 to 26 °C) and water with 0.5 g/L of NaCl was used as the work fluid to stabilize the electrical conductivity reading. Three repetitions per volumetric flow rate were performed for the complete process, heat exchangers and holding tubes, and five repetitions per volumetric flow rate were performed for the data acquisition system, given the higher sensibility. It was observed the need to apply the numerical convolution procedure to evaluate the distortion in the RTD curve of the process caused by the flow through the data acquisition system. Five flow models were tested: axial dispersion, PFR+CSTR association, tanks in series, generalized convection and y-laminar. The adjustment criterion of the parameters was the minimization of the quadratic error between experimental and calculated E(t) values. The axial dispersion and y-laminar models provided the best adjustments for the holding tubes and the generalized convection model provided the best adjustment for the heat exchangers. The flow regime during the experiments varied between laminar and transition (Reynolds values between 1259 and 4238). The results for the complete system and heat exchangers were satisfactory, for the holding tubes was observed a great uncertainty in the parameters values and was observed the importance of numerical convolution in small volume systems.
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Tipos de holomorfia em espaços de Banach / Holomorphy types on a Banach spacesJatobá, Ariosvaldo Marques 12 August 2018 (has links)
Orientador: Jorge Tulio Mujica Ascui / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Matematica, Estatistica e Computação Cientifica / Made available in DSpace on 2018-08-12T04:40:55Z (GMT). No. of bitstreams: 1
Jatoba_AriosvaldoMarques_D.pdf: 617454 bytes, checksum: b1f5fca80565a5a0f7b273ed5238b6ee (MD5)
Previous issue date: 2008 / Resumo: Neste trabalho introduzimos e estudamos os espaços das funções inteiras ?-holomorfas de tipo limitado. Em particular obtemos resultados de dualidade via a transformada de Borel e provamos resultados de existência e aproximação para equações de convolução. Os resultados provados generalizam resultados anteriores deste tipo devido a C. Gupta [21], M. Matos [28] e X. Mujica [32]. Nós estudamos as relações entre o espaço Hb(E; F) das funções inteiras de tipo limitado, o espaço HNb(E; F) das funções inteiras nucleares de tipo limitado, o espaço HPIb(E; F) das funções inteiras Pietsch-integrais de tipo limitado, e o espaço HGIb (E; F) das funções inteiras Grothendieck-integrais de tipo limitado. Estendemos para o caso de funções inteiras resultados de R. Alencar [2] e R. Cilia e J. Gutierrez [10] no caso de polinômios homogêneos. / Abstract: In this work we introduce and study functions of ?-holomorphy type of bounded type. In particular we obtain a duality result via the Borel transform and we prove existence and approximation results for convolution equations. The results we prove generalize previous results of this type due to C. Gupta [21], M. Matos [28] and X. Mujica [32]. We study the relationships among the space Hb(E; F) of entire mappings of bounded type, the space HNb(E; F) of entire mappings of nuclear bounded type, the space HPIb(E; F) of entire mappings of Pietsch integral bounded type, and the space HGIb(E; F) of entire mappings of Grothendieck integral bounded type. We extend to the case of entire mappings several results due to R. Alencar [2] and R. Cilia and J. Gutiérrez [10] in the case of homogeneous polynomials. / Doutorado / Analise Funcional / Doutor em Matemática
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