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Design and validation of an experiment for the detection and prediction of stall and surge in a PT6/T400 turboshaft engine /Chalmers, Jennifer L. Y., January 1900 (has links)
Thesis (M.App.Sc.) - Carleton University, 2006. / Includes bibliographical references (p. 99-102). Also available in electronic format on the Internet.
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The Fast Fourier Transform in the MPEG encoding algorithmBreimyer, Paul. January 2001 (has links)
Thesis (B.A.)--Haverford College, Dept. of Computer Science, 2001. / Includes bibliographical references.
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A study of ellipsoidal variance as a function of mean CIELAB values in a textile data set /Ansell, Seth. January 1995 (has links)
Thesis (M.S.)--Rochester Institute of Technology, 1995. / Typescript. Includes bibliographical references (leaves 130-131).
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Detecting glaucoma in biomedical data using image processing /Bhatt, Mittal Gopalbhai. January 2005 (has links)
Thesis (M.S.)--Rochester Institute of Technology, 2005. / Typescript. Includes bibliographical references (leaves 54-56).
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On the regularity of refinable functionsOnwunta, Akwum A. 03 1900 (has links)
Thesis (MSc (Mathematical Sciences. Physical and Mathematical Analysis))--University of Stellenbosch, 2006. / This work studies the regularity (or smoothness) of continuous finitely supported refinable
functions which are mainly encountered in multiresolution analysis, iterative interpolation
processes, signal analysis, etc. Here, we present various kinds of sufficient conditions on
a given mask to guarantee the regularity class of the corresponding refinable function.
First, we introduce and analyze the cardinal B-splines Nm, m ∈ N. In particular, we
show that these functions are refinable and belong to the smoothness class Cm−2(R). As
a generalization of the cardinal B-splines, we proceed to discuss refinable functions with
positive mask coefficients. A standard result on the existence of a refinable function in
the case of positive masks is quoted. Following [13], we extend the regularity result in
[25], and we provide an example which illustrates the fact that the associated symbol to
a given positive mask need not be a Hurwitz polynomial for its corresponding refinable
function to be in a specified smoothness class. Furthermore, we apply our regularity result
to an integral equation.
An important tool for our work is Fourier analysis, from which we state some standard
results and give the proof of a non-standard result. Next, we study the H¨older regularity
of refinable functions, whose associated mask coefficients are not necessarily positive, by
estimating the rate of decay of their Fourier transforms. After showing the embedding of
certain Sobolev spaces into a H¨older regularity space, we proceed to discuss sufficient conditions
for a given refinable function to be in such a H¨older space. We specifically express
the minimum H¨older regularity of refinable functions as a function of the spectral radius
of an associated transfer operator acting on a finite dimensional space of trigonometric
polynomials.
We apply our Fourier-based regularity results to the Daubechies and Dubuc-Deslauriers
refinable functions, as well as to a one-parameter family of refinable functions, and then
compare our regularity estimates with those obtained by means of a subdivision-based
result from [28]. Moreover, we provide graphical examples to illustrate the theory developed.
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Fourier approaches to the theory of volume holographyLewis, J. W. January 1984 (has links)
No description available.
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Analise de sinais em regime transiente aplicando a tecnica de WAVELETPENHA, ROSANI M.L. da 09 October 2014 (has links)
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Estudo do eletrocardiograma sob uma abordagem matemática. / Electrocardiogram evaluation under a mathematical approach.Tito Coutinho Melco 10 November 2006 (has links)
O eletrocardiograma transMITe informações com relação à passagem do pulso elétrico pelo coração e, conseqüentemente, do funcionamento deste. Desde o início da sua utilização, possibilitada pelo trabalho de Willem Einthoven criando a primeira máquina capaz de medir o pulso elétrico de forma não invasiva e com sensibilidade forte o bastante para ser capaz de produzir um gráfico proveitoso, o eletrocardiograma é muito utilizado para avaliação clínica de pacientes. Entretanto a evolução das máquinas que o descrevem não foi muito além do que o elaborado por Einthoven no início do século 20. As máquinas capazes de captar o eletrocardiograma se tornaram menores (até portáteis para algumas aplicações), gráficos passaram a ser disponibilizados em telas de vídeo (ao invés das fitas de papel) e, como maior evolução, as máquinas que observam o eletrocardiograma passaram a conseguir captar a ocorrência de um ciclo cardíaco com alta confiabilidade e, atualmente, passaram a medir também o parâmetro ST com precisão deliMITada (necessitando ajuda do operador para ajuste em alguns casos). É baseado nestes fatos que esta dissertação procura estudar algoritmos matemáticos, de forma mais focada nos modelos do impulso elétrico durante os ciclos cardíacos, e avaliar suas capacidades de interpretar parâmetros do ciclo de ECG de forma precisa e rápida para que o médico tenha prontamente os dados necessários para realizar a avaliação clínica do paciente. Em primeira análise foram estudados os algoritmos para detecção do pulso de eletrocardiograma (detecção da onda R), em seguida feito o janelamento da curva de ECG a fim de separar os ciclos cardíacos. A partir deste ponto foram analisados os modelos matemáticos gerados por equações polinomiais, Transformada de Fourier e Transformada wavelet. E, com o intuito de filtrar ruídos e gerar derivações não medidas, foi implementado um filtro de kalman em um modelo vetorial do eletrocardiograma. Para avaliar os resultados obtidos foram utilizados requisitos de desempenho declarados pelo FDA norte americano e pela norma européia IEC60601-2-51. Essas análises foram feitas através da utilização dos algoritmos gerados nas curvas provindas do banco de dados do PhisioNet. O método polinomial não foi considerado interessante na medida em que não possibilita gerar uma equação para um ciclo cardíaco, mas sim várias equações (uma para cada ponto do ciclo). Os demais métodos apresentaram melhor eficiência na medida em que foram capazes de gerar parâmetros com significado físico e possibilitando melhor caracterização de pontos importantes da curva do eletrocardiograma. / The electrocardiogram gives information related to the passage of an electric pulse through the heart and, therefore, to his state function. Since the beginning of electrocardiogram utilization, thanks to the work of Willem Einthoven building the first machine capable of measuring the electric pulse non-invasively and with sensitivity enough to be able to provide a profitable graph, it is widely used for clinical evaluation of patients. However the evolution of the machines that describes the electrocardiogram hadn´t much more advances since the elaborated by Einthoven in the beginning of the 20th century. They become smaller (even portable for some applications), the graphs are now displayed in video screens (instead of the paper strip) and, taking place as the biggest evolutions, machines that observes the electrocardiogram became able to recognize a cardiac cycle with high reliability and, more recently, became able to measure the ST parameter with liMITed precision (it needs the help of the operator to set specific measuring points in some cases). It is based in these facts that this dissertation looks for analyzing mathematic algorithms, more specifically the mathematic models of the electric impulse during the cardiac cycles, and evaluate their capacities to expound ECG parameters in a fast and reliable way in order to the physician receive promptly the data needed for his clinical evaluation of the patient. For the first step were analyzed some algorithms for electrocardiogram pulse detection (detection of R wave), in the following step were done the windowing of the ECG wave in order to separate the cardiac cycles. In this step were analyzed the mathematic models generated by polynomial equations, Fourier Transform and Wavelet Transform. And, in order to filter noises and generate leads not measure, it was implemented a kalman´s filter at a vector model. To evaluate the obtained results were used the requirements of performance given by north-american FDA and by the European rule IEC60601-2-51. These evaluations were done by executing the generated algorithms in the waves supplied by the databank PhisioNet. The polynomial method weren´t considered interesting because it weren´t able to generate an equation for the cardiac cycle, but many equations (one for each point of the cycle). The other methods showed a better efficiency since they were capable of generate parameters with physical meaning and being able to do a better characterization of the important points of the electrocardiogram wave.
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Analise de sinais em regime transiente aplicando a tecnica de WAVELETPENHA, ROSANI M.L. da 09 October 2014 (has links)
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Metodos de diferenças finitas : conceitos e interpretações / Finite-difference methods : concepts and interpretationSousa, Nadson de 13 August 2018 (has links)
Orientador: Ricardo Caetano Azevedo Biloti / Dissertação (mestrado profissional) - Universidade Estadual de Campinas, Instituto de Matematica, Estatistica e Computação Cientifica / Made available in DSpace on 2018-08-13T04:58:29Z (GMT). No. of bitstreams: 1
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Previous issue date: 2009 / Resumo: O presente trabalho aborda os métodos de diferenças finitas com suas propriedades e aplicações. Iniciamos com uma revisão histórica, destacando alguns matemáticos que participaram do desenvolvimento da teoria de métodos de diferenças. Em seguida, apresentamos alguns modelos matemáticos compostos por equações diferenciais. Através da equação de advecção, estudamos métodos de diferenças explícitos, com especial enfoque para as propriedades de erro de truncamento, consistência, estabilidade e convergência dando ênfase ao Teorema de Lax. Estudamos a análise de Fourier e a condição de von Neumann para interpretar a amplitude, a dissipação e a dispersão das soluções numéricas. Abordamos os métodos Upwind, de Lax-Friedrichs e de Lax-Wendroff. Por fim, exemplificamos numericamente os conceitos e propriedades estudados com comparações entre os métodos, aplicados em um problema teste. / Abstract: The present work approaches finite-difference methods, their properties, and their applications. We present a historical review, including some mathematieians who participated in the development of the theory of differences. Furthermore, we present some mathematical models consisting of differential equatiolls. Through the advection equationl, we study explicit finite-difference methods, detailing their truncation error, consistency, stability and conlvergence properties. We employ Fourier analysis and the von Neumann condition to study the amplitude, dissipation and dispersion of numerical solutions. We compare three methods: Upwind, Lax-Friedrichs and Lax-Wendroff. Finally, we perform numerical tests to illustrate the concepts and properties studied in this work. / Mestrado / Analise Numerica / Mestre em Matemática
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