An investigation into the complex function of muscle using non-invasive imaging and novel analytical approaches. / The human body is inherently complex as seen through the structural organization of muscle in terms of its contractile subunit organization and scaling, innervation patterns, and vascular organization. However, the functional complexity of muscle such as its state of oxygenation, metabolism or blood-flow has been less well explored. Thus in an effort to improve our understanding of muscle, blood oxygenation level dependent (BOLD) magnetic resonance imaging of the lower leg, at rest and during a variety of weighted plantar-flexion paradigms, at 40% maximal voluntary contraction, was employed. Prior to experimentation, on 11 healthy subjects, an ergometer and electromyogram (EMG), suitable for use within the MRI, were constructed to allow for concurrent exercise and image acquisition. After collecting muscle BOLD data, four novel techniques were using to describe muscle function. The first technique used the fractal dimension, a measure of complexity, conveying the rate of variation of muscle blood flow at rest. This technique was able to determine differences between the muscles of lower leg, which have varying distributions of muscle fibre types based on function. The second exploratory technique was the use of the phase space, which provides insight into state/state-transitions of a system over time. The phase space representation of the BOLD signal provided novel insight into the muscle activation state. It demonstrated that muscle has more than the two blood flow states of reduced levels at rest and increased levels when exercising. The third technique involved using a signal saturation (SAT) region, proximal to the imaging region, to mitigate the arterial in-flow effects to more accurately represent muscle activation. By observing the correlation between the ideal reference and recorded signal, the acquisition with the arterial suppression improved the assessment of what regions in the muscle were active in the range borderline activation, which has the highest uncertainty. The final outlook on muscle behaviour involved using measures of fatigue from the collected EMG data to develop novel metrics of fatigue based on the BOLD signal. Concurrent BOLD and EMG of the anterior compartment of the lower leg during a plantar-flexion block design, demonstrated that the change in blood-flow between rest and contracted states is an excellent indicator of muscle fatigue. The primary outlook of this thesis is to provide a unique data collection and analytic framework to describe muscle behaviour, which was achieved using non-invasive measures with a complex outlook. / Thesis / Master of Applied Science (MASc) / The human body is complex, and an incredible amount of research has been done to better understand it. Specifically, muscle is built and works in a complex way to allow us to move and perform everyday tasks. There are many diseases that affect how a muscle works, which is why there is a need to describe muscle performance when it is healthy and unhealthy. In this research, muscle behaviour is explored by taking pictures of the leg. From these pictures the blood flow in the calf and shin was measured both when staying still and when performing exercise. Four new techniques were created to describe the blood flow in the leg. The first technique measured how complex the muscle activity is, while staying still. If blood-flow changes a lot in a short amount of time, it is complex. This showed that the different components of muscle, either used for stamina or power, receive blood differently. The second technique used a different way of looking at the muscle to show that there are many different rates and amounts of blood-flow in the muscle. It revealed that muscle has more than the two blood flow options of 1) the normal level when resting and 2) the increased level when exercising. The third technique involved using an image filter to get a clean image of the muscle without the blood vessels affecting or misrepresenting the image. It was able to show what muscle regions were involved in exercise more accurately than before. The final technique involved measuring muscle electricity and blood flow at the same time, to find out when the muscle was exhausted. It demonstrated that muscle, when exhausted, showed larger changes in blood flow when going from resting to exercising. Overall, this research described how muscle performs in healthy individuals using new techniques. These techniques can now be used to compare healthy muscle to damaged/diseased muscle to determine how the muscle is recovering or to diagnose muscular disease.

This paper will examine analogues of Cantor sets, called fractal squares, and some of the geometric ways in which fractal squares raise issues not raised by Cantor sets. Also discussed will be a technique using directed graphs to prove bilipschitz equivalence of two fractal squares. / Ph. D.

The work presented here addresses an important topic in thermal radiation detection when gold-black is used as an absorber. Sought is a model to simulate the absorption of thermal radiation by gold-black. Fractal geometry is created to simulate the topology of gold-black. Then electrical circuits based on the topology are identified that capture the physics of the interaction between the gold-black material and incident electro-magnetic radiation. Parameters of the model are then adjusted so results obtained are comparable to absorption data from the literature. Potential next-generation radiometric instruments will likely involve thermal radiation detectors using gold-black as an absorbing medium. A model that accurately simulates gold-black absorption will be an important tool in their design. / Master of Science

The sun is constantly emitting electrons and ions as magnetized plasma, forming the solar wind and carrying with it the sun’s rotating magnetic field. The solar wind subsequently interacts with Earth’s magnetosphere and the magnetospheres of other planets. Occasionally large amounts of magnetized plasma are released at one time in a Corona mass ejection (CME). When the CME interacts with Earth’s magnetic field, it induces perturbations that may have a significant impact on critical infrastructure, for instance, by disturbing communication systems, and inducing currents on pipelines and electric power lines, which in turn may cause increased corrosion or blackouts, among other effects. In this dissertation, we analyze measured electrical signals provided to us by the Finnish Meteorological Institute, which were induced by geomagnetic storms on pipelines located in Finland and recorded in 2003. Specifically, we perform a wavelet leader multifractal analysis of these current signals to generate singularity spectra, and then using the bootstrapping technique, we apply statistical tests to show that these signals exhibit multifractal characteristics. We also performed surrogate testing to show that these characteristics were unique to the signal. / Ph.D. / Earth’s weather affects all of us every day. The solar space environment has weather of its own that affects us as well. Storms of a size that far exceed anything on Earth can impact Earth and affect our infrastructure. One of the most powerful phenomena that occur, called solar corona mass ejections, results when the sun ejects a large amount of plasma. This can interact with the Earth’s magnetic field, which in turn induces perturbations that may have a significant impact on critical infrastructure, for instance, by disturbing communication systems, and inducing currents on pipelines and electric power lines. The currents can cause increased corrosion or blackouts, among other effects. In this dissertation, we analyze measured electrical signals provided to us by the Finnish Meteorological Institute, which were induced by geomagnetic storms on pipelines located in Finland and recorded in 2003. Specifically, we perform a statistical analysis of these current signals to decide whether they exhibit multifractal characteristics.

Os condomínios e loteamentos fechados constituem um fenômeno urbano que vem se espalhando por todas as metrópoles brasileiras. Desde o final dos anos 1980, podemos observar um grande aumento no número de condomínios fechados dentro da Região Metropolitana de São Paulo (RMSP). Os condomínios e loteamentos fechados, antes destinados à moradia da classe alta e localizados em grandes áreas das zonas periféricas da RMSP, atualmente atendem outras classes sociais e possuem características bastante distintas (tamanho da gleba, unidade habitacional, serviços coletivos). A preocupação com conforto foi suplantada pela necessidade de segurança e pelo status. A proliferação desses loteamentos e condomínios fechados nos últimos quinze anos vem modificando a configuração espacial de algumas áreas da Região Metropolitana. Segundo alguns autores, o padrão centro rico versus periferia pobre, que caracterizou os estudos sobre a RMSP, entre os anos 1940 e 1980, alterou-se na última década para um modelo fractal de segregação. Esta Tese pretende verificar a pertinência do novo modelo fractal de segregação espacial, tomando como referência os condomínios horizontais residenciais fechados, e mostrar, a partir de levantamento realizado na Região Metropolitana de São Paulo, que parte das premissas relativas aos condomínios fechados não são absolutas. / Gated communities constitute an urban phenomenon that is nowadays spreading all over the Brazilian metropolis. Since the 1980s, we can observe an increasing number of gated communities within the São Paulo Metropolitan Area (SPMA). The gated communities, initially located at suburban areas and used by upper classes, at the present time serve other social classes and have new and distinct characteristics (size and location, houses sizes, services at the collective areas, etc). The initial concerning to comfort was substituted by the need of security and possibly the search for status. This Thesis analyses if the new fractal pattern of spatial segregation has overlapped the rich center X poor suburbia pattern that characterized the SPMA between 1940 and 1980, using the gated communities as case studies. And also pretends to demonstrate that part of the premises about gated communities is not absolute.

Submitted by Michele Mologni (mologni@unoeste.br) on 2019-01-23T12:44:40Z No. of bitstreams: 1 Marcelo Fernandes Tribst.pdf: 777315 bytes, checksum: b27a7e6b55bc34cf1e1df838b6e087c4 (MD5) / Made available in DSpace on 2019-01-23T12:44:40Z (GMT). No. of bitstreams: 1 Marcelo Fernandes Tribst.pdf: 777315 bytes, checksum: b27a7e6b55bc34cf1e1df838b6e087c4 (MD5) Previous issue date: 2018-09-21 / Smoking is a global concern because of the impact on public health, particularly in causing chronic illness and suffering for millions of people and is a leading cause of preventable deaths worldwide. The global annual cost of health services associated with smoking is estimated at US$ 422 billion, equivalent to US$ 56.34 per person. This represents 5.7% of total health expenditure in the world. The blend of cigarette smoke contains around 4.7000 toxic substances that are associated with decreased bone mass and influencing the process of bone healing and remodeling. Bone tissue being multifunctional and subject to cell differentiation at different stages of development is more susceptible to receiving the deleterious action of the main smoking agent of cigarette smoke. Functional, probiotic, prebiotic and symbiotic foods due to their ability to improve intestinal absorption and compete with pathogenic microorganisms may contribute to the improvement of bone quality. The objective of this study was to evaluate the effects of dietary supplementation of probiotic, prebiotic and symbiotic supplements on mineral composition, histomorphometry, biomechanical properties and fractal dimension of the femur of growing rats, chronically exposed to cigarette smoke (PT). Sixty-four young male rats were randomly assigned to eight groups (n = 8): control (C) [basal diet (DB)]; probiotic (Pro) [DB + probiotic (Lactobacillus acidophilus, Enterococcus faecium, Bifidobacterium thermophilum and Bifidobacterium longum (2-5 109 CFU each)], prebiotic (Pre) [DB + prebiotic (mannan oligosaccharide)], symbiotic probiotic + prebiotic + PT), prebiotic smoker (PreT) (DB + prebiotic + PT), smoker control (PT + The rats were sacrificed after 189 days of experimental period, and the results showed that probiotic, prebiotic and symbiotic supplementation improved significantly (P <0.05), as well as symbiotic smoker (SymT) (DB + prebiotic + probiotic + PT). The results showed that the functional food supplementation, probiotic, prebiotic, and the presence of the functional, probiotic, optical or symbiotic improved bone health in growing rats chronically exposed to cigarette smoke. / O tabagismo é uma preocupação global devido ao impacto na saúde pública, particularmente em causar doenças crônicas e sofrimento de milhões de pessoas e é uma das principais causas de mortes evitáveis em todo o mundo. Estima-se em US$ 422 bilhões o custo global anual dos serviços de saúde associados ao tabagismo, equivalente a US$ 56,34 por pessoa. Isso representa 5,7% do gasto total em saúde no mundo. A mistura da fumaça do cigarro contém por volta de 4.700 substâncias tóxicas que estão associados à diminuição de massa óssea e influenciando no processo de consolidação e remodelação óssea. O tecido ósseo por ser multifuncional e sujeito a diferenciação celular em diferentes estágios de desenvolvimento é mais susceptível a receber á ação deletéria da nicotina, principal agente agressor da fumaça do cigarro. Os alimentos funcionais, probiótico, prebiótico e simbiótico, devido sua capacidade de melhorar a absorção intestinal e competir com microrganismos patógenos podem contribuir para a melhora da qualidade óssea. O objetivo desse estudo foi avaliar os efeitos da suplementação na dieta de suplementos alimentares: probiótico, prebiótico e simbiótico, na composição mineral, histomorfometria, propriedades biomecânicas e dimensão fractal do fêmur de ratos em fase de crescimento, expostos cronicamente a fumaça do cigarro (PT). Sessenta e quatro ratos machos jovens foram randomicamente distribuídos em oito grupos (n=8): controle (C) [dieta basal (DB)]; probiótico (Pro) [DB + probiótico (Lactobacillus acidophilus, Enterococcus faecium, Bifidobacterium thermophilum e Bifidobacterium longum (2–5 109 UFC cada)]; prebiótico (Pre) [DB + prebiótico (mananoligossacarídeo)]; simbiótico (Sym) (DB + probiótico + prebiótico); controle fumante (CT) [DB + protocolo de exposição ao tabagismo passivo (PT)]; probiótico fumante (ProT) (DB + probiótico + PT); prebiótico fumante (PreT) (DB + prebiótico + PT); e simbiótico fumante (SymT) (DB + prebiótico + probiótico + PT). Os ratos foram sacrificados após a189 dias de período experimental e os resultados revelaram que a suplementação com probióticos, prebióticos e simbióticos melhoraram significativamente (P<0,05) os parâmetros: P, Ca, Mg, DMO, CMO, resistência, resiliência, dimensão fractal e tamanho da área das diáfises dos fêmures dos ratos expostos cronicamente ou não a fumaça do cigarro. Concluímos que a suplementação dos alimentos funcionais, probiótico, prebiótico ou simbiótico, melhorou a saúde óssea de ratos em fase de crescimento expostos cronicamente a fumaça do cigarro.

A diversidade de espécies presentes no riquíssimo reino vegetal torna o processo de identificação de órgãos foliares uma tarefa muito complexa. A biodiversidade das espécies, associada aos modelos tradicionais de taxonomia, transforma essa tarefa em um verdadeiro desafio para os pesquisadores. Neste trabalho é apresentada uma nova abordagem para identificação de espécies vegetais baseada em características internas dos órgãos foliares. A coleta de informações é realizada através de técnicas de visão computacional e análise de imagens, através das quais são extraídas características relativas à complexidade (dimensão fractal) e biometria dos órgãos foliares. A eficiência da metodologia desenvolvida foi avaliada em casos reais de identificação de espécies, em que foram utilizados dois conjuntos de imagens: espécies da Mata Atlântica e do Cerrado brasileiro, e espécies de maracujás silvestres do gênero Passiflora. Para classificação das espécies foram utilizadas as técnicas de reconhecimento padrões de análise de agrupamentos e redes neurais artificiais. / The plant species diversity makes their correct identification a very complex task. The traditional taxonomy models, associated with species biodiversity, has been transformed this task in a challenger for the researches. This work presents a new approach to plant species identification, based on internal characteristics of leaf form. The data are collected by computer vision and shape analysis techniques, which extracts features from complexity (fractal dimension) and biometry of plant species. The methodology efficiency was evaluated with real cases of species identification: digital images of Mata Atlântica and brazilian Cerrado species; and passion fruit species of genus Passiflora. The species classifications are performed using pattern recognition techniques as clustering and artificial neural networks.

This work is dedicated to the study of the structure of attractors of dynamical systems with the objective of estimating their fractal dimension. First we study the case of exponential global attractors of some generalized gradient-like semigroups in a general Banach space, and estimate their fractal dimension in terms of themaximumof the dimension of the local unstablemanifolds of the isolated invariant sets, Lipschitz properties of the semigroup and rate of exponential attraction. We also generalize this result for some special evolution processes, introducing a concept of Morse decomposition with pullback attractivity. Under suitable assumptions, if (A, \'A POT. \') is an attractor-repeller pair for the attractor A of a semigroup {T (t ) : t 0}, then the fractal dimension of A can be estimated in terms of the fractal dimension of the local unstable manifold of \'A POT. \', the fractal dimension of A, the Lipschitz properties of the semigroup and the rate of the exponential attraction. The ingredients of the proof are the notion of generalized gradient-like semigroups and their regular attractors, Morse decomposition and a fine analysis of the structure of the attractors. Also, making use of the skew product semiflow and its Morse decomposition, we give some estimates of the fractal dimension of the pullback attractors of non-autonomous dynamical systems / Este trabalho é dedicado ao estudo da estrutura dos atratores de sistemas dinâmicos com o objetivo de obter estimativas de suas dimensões fractais. Primeiramente estudamos o caso de atratores globais exponenciais de alguns semigrupos gradient-like generalizados em um espaço de Banach geral, e estimamos suas dimensões fractais em termos da máxima dimensão das variedades instáveis locais dos conjuntos invariantes isolados, a propriedades de Lipschitz do semigrupo e da taxa de atração exponencial. Também generalizamos este resultado para alguns processos de evoluções especiais, introduzindo um conceito de decomposição de Morse com atração pullback. Sob hipóteses apropriadas, se (A, \'A POT. \') é um par atrator-repulsor para o atratorA de um semigrupo {T (t ) : t 0}, então a dimensão fractal de A pode ser estimada em termos da dimensão fractal da variedade instável de \'A POT. \', a dimensão fractal de A, as propriedades de Lipschitz do semigrupo e a taxa de atração exponencial. Os ingredientes da demonstração são a noção de semigrupos gradient-like e seus atratores regulares, decomposição de Morse e uma análise fina da estrutura dos atratores. Além disto, fazendo uso do skew product semiflow e sua decomposição de Morse, damos estimativas da dimensão fractal dos atratores pullback de sistêmas dinâmicos não-autônomos

Made available in DSpace on 2017-07-21T20:43:48Z (GMT). No. of bitstreams: 1 Charles Betuel Mansende Mvumbi.pdf: 3357827 bytes, checksum: 822a91a949448c4769ce680ef684f74d (MD5) Previous issue date: 2016-01-29 / The ceramic porcelains are produced from natural raw materials (silica, feldspar and kaolin). In some applications other materials are added to increase the mechanical and dielectric strength. They are used in the manufacture of several products. Therefore, they are very studied and have been developed for long time. In this work, porcelains with different compositions were characterized and submitted to fragmentation by mechanical disruption in a ballistic impact testing. Generally the mechanical disruption in the materials produces a power dissipation forming cracks and fracture surfaces having an irregular geometry. The main objective of this work was to characterize the microstructure and the fractal fracture surface in porcelains. For comparison, the impact tests were also performed on commercial glass and acrylic. The evaluation of the fracture surface and the fractal dimension of rupture was performed by analyzing the fraction of the fragments as a function of the probability of fracture. The samples were prepared in the form of cylindrical disks with a thickness and fixed diameters. Mechanical impact test was made on the center of the disks for different materials, maintaining the same test conditions. The results of the size and mass of the fragments were obtained as a function of the impact energy, thickness, diameter and kind of material. Thus, it was possible to obtain a correlation between the test conditions and the composition of the material with the fractal pattern breakage. It has been found that the compositions used in porcelain, has a fracture toughness which is between the glass and acrylic. A correlation between strength properties to the patterns of formed crack was made. It was noticed that the number, the shape of cracks and the branches form a pattern that is associated with the impact energy and material type. / As porcelanas são cerâmicas produzidas a partir de matérias primas naturais (sílica, feldspato e caulim). Em algumas aplicações são adicionadas outras matérias primas para o aumento da resistência mecânica e dielétrica. Elas são usadas na fabricação de variados produtos. Portanto, elas são muito estudadas e vêm sendo desenvolvidas há muito tempo. Neste trabalho, porcelanas com diferentes composições foram caracterizadas e submetidas à fragmentação por ruptura mecânica em um ensaio de impacto balístico. A ruptura mecânica nos materiais em geral produz uma dissipação de energia formando trincas e superfícies de fratura que tem uma geometria irregular. O principal objetivo deste trabalho foi a caracterização da microestrutura e a caracterização fractal da superfície de fratura de porcelanas. Para comparação, os ensaios de impacto também foram feitos em vidro e acrílico comercial. A avaliação da superfície de fratura e da dimensão fractal de ruptura foi feita pela análise da fração de fragmentos em função da probabilidade de fratura. Os corpos de prova foram preparados na forma de discos cilíndricos, com espessura e diâmetros fixos. O ensaio de impacto mecânico foi feito sobre o centro dos discos, para os diferentes materiais, mantendo-se as mesmas condições de ensaios. Os resultados, do tamanho e massa dos fragmentos, foram obtidos em função da energia, espessura, diâmetro e do tipo de material. Desta forma, foi possível obter uma correlação entre as condições de ensaio e a composição do material com o padrão de ruptura fractal. Verificou-se que a porcelana nas composições usadas possui uma tenacidade à fratura que se situa entre a do vidro a do acrílico. Finalmente foi feita uma correlação entre as propriedades de resistência mecânica com os padrões de trinca formado. Percebeu-se que o número, a forma das trincas e as ramificações formam um padrão que está relacionado com a energia de impacto e o tipo de material.

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / A pesquisa teve como objetivo correlacionar diferentes defeitos e suas criticidades, em corpos de prova de aÃo ASTM A516 grau 60 para ensaio CTOD, cujos detalhes foram feitos no metal de base, no metal de solda e na zona termicamente afetada de uma junta soldada, com os sinais de emissÃo acÃstica obtidos durante os ensaios. Quatro mÃtodos de anÃlise fractal foram utilizados: anÃlise re-escalada de Hurst (R/S), dimensÃo de contagem de caixas, dimensÃo de cobetura mÃnima e anÃlise de flutuaÃÃo sem tendÃncias (DFA). Um nÃmero mÃnimo de pontos necessÃrios para a obtenÃÃo dos expoentes associados a cada mÃtodo de anÃlise foi determinado para os vÃrios sinais, bem como o efeito de diferentes mÃtodos de filtragem nesses expoentes. Verificou-se que nenhum dos mÃtodos isoladamente conseguiu caracterizar os defeitos nem os regimes de carregamento. Entretanto, utilizando-se representaÃÃes bidimensionais de todos os expoentes juntamente com o desvio padrÃo dos sinais foi possÃvel estabelecer, de forma satisfatÃria, uma caracterizaÃÃo hierÃrquica dos defeitos e regimes de carregamento. / The research aims to correlate different defects and their criticidades in specimens of ASTM A516 grade 60 CTOD test, details of which were made in the base metal in the weld metal and heat affected zone of welded joint with acoustic emission signals obtained during the tests. Four fractal analysis methods were applied: re-scaled analysis Hurst (R / S), the box counting dimension, cobetura minimum dimension and analysis of fluctuation without bias (DFA). A minimum number of points required to obtain the exponent associated with each method of analysis was determined for the various signals and the effect of different filtering methods such exponents. It was found that none of the methods alone failed to characterize or defects charging schemes. However, using two-dimensional representations of all the exponents with the standard deviation of signals could be made in a satisfactory way, a hierarchical characterization of defects and charging systems.