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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
821

Arremessos de basquetebol e sequências de Bernoulli : uma aplicação de métodos estatísticos para análise de séries temporais binárias / Basketball shots and sequences of Bernoulli : an application of statistical methods for analysis of binary time series

Costa, Michelly Guerra, 1984- 21 August 2018 (has links)
Orientador: Cristiano Torezzan / Dissertação (mestrado profissional) - Universidade Estadual de Campinas, Instituto de Matemática, Estatística e Computação Científica / Made available in DSpace on 2018-08-21T20:22:07Z (GMT). No. of bitstreams: 1 Costa_MichellyGuerra_M.pdf: 529315 bytes, checksum: 0d134b8239c73b591005b036b0339e20 (MD5) Previous issue date: 2012 / Resumo: No presente trabalho investigamos as semelhanças entre registros de lançamentos extraídos de jogos reais de basquetebol e sequências aleatórias geradas por algoritmos computacionais. Nosso principal objetivo é comparar o comportamento das sequências de arremessos consecutivos de jogadores ao longo de uma temporada com sequências aleatórias de zeros e uns (sequências de Bernoulli) geradas computacionalmente. Para tanto, foram desenvolvidos algoritmos computacionais específicos para os testes e implementados na plataforma Scilab para análise dos dados. Os testes realizados neste trabalho indicam que, de maneira geral, não existem diferenças estatísticas entre os dois conjuntos de dados considerados. Além de uma breve revisão sobre testes estatísticos e sobre o problema da boa fase no jogo de basquetebol, apresentamos diversos exemplos visando tornar o texto acessível para alunos de graduação ou demais interessados em estatística aplicada, em especial ao esporte / Abstract: In this work we investigate the similarities between records of shots extracted from real basketball games and random sequences generated by computational algorithms. Our goal is to compare the behavior of sequences of consecutive shots of players throughout a season with random sequences of zeros and ones (Bernoulli sequences) generated computationally. For this purpose, computational algorithms have been developed for specific tests and implemented in the Scilab platform. The tests performed in this study indicate that, in general, there are no statistical differences between the two sets of data considered. Besides a brief review of statistical tests and the problem of good stage in the game of basketball, we present several examples in order to make the text accessible to undergraduates or others interested in applied statistics, especially the ones concerning this sport / Mestrado / Matematica / Mestra em Matemática
822

Utilização de dados PALSAR/ALOS (banda L) no monitoramento da cana-de-açúcar / Monitoring sugarcane with PALSAR/ALOS (L band) data

Picoli, Michelle Cristina Araújo, 1981- 20 August 2018 (has links)
Orientador: Rubens Augusto Camargo Lamparelli / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agrícola / Made available in DSpace on 2018-08-20T12:04:36Z (GMT). No. of bitstreams: 1 Picoli_MichelleCristinaAraujo_D.pdf: 3300395 bytes, checksum: 8977f82fac78de53ad03a7e436b10bc1 (MD5) Previous issue date: 2012 / Resumo:A cana-de-açúcar (Saccharum spp.) exerce papel fundamental na economia na medida em que fornece matéria prima para a produção das comodities açúcar e álcool. Dentro deste contexto a necessidade de informações, as quais possibilitam o acompanhamento desta, é extremamente importante porque permite avaliar a disponibilidade da matéria prima e sua demanda. Para isto, é necessário o monitoramento constante da cultura e uma das formas de se fazer é com o uso de imagens de sensoriamento remoto. Porém, sabe-se que nem sempre isso é possível devido aos períodos chuvosos que ocorrem durante a safra e, portanto, dificultando a aquisição de imagens de satélite livre de nuvens. Para tentar minimizar este problema, a utilização de sensores ativos, como é o caso dos sensores radar de abertura sintética (SAR - Synthetic Aperture Radar), pode ajudar. Os sensores SAR podem coletar dados da superfície em áreas com freqüente cobertura de nuvens e névoa, operando inclusive à noite. Sendo assim, este trabalho teve como objetivo: analisar o potencial das imagens de radar PALSAR/ALOS, polarizações HH e HV, no monitoramento da cultura de cana-de-açúcar, determinar os efeitos das linhas de plantio em culturas de cana-de-açúcar nessas imagens de radar e estimar a produtividade agrícola em talhões de cana-de-açúcar, por meio de um modelo utilizando imagens de radar do sensor PALSAR/ALOS e dados agronômicos, nas safras: 2007/08, 2008/09, 2009/10 na região nordeste do Estado de São Paulo. Os resultados mostraram que foi capaz de detectar mudanças na estrutura (biomassa) da cana-de-açúcar. Os valores médios do coeficiente de retroespalhamento (?°), provenientes de talhões, com linhas de plantio perpendiculares, na polarização HH, foram mais altos que os dos talhões com linhas paralelas à linha de visada do sensor (0,7 a 2,3 dB mais altos, 1,2 dB em média). Para a polarização HV não houve diferença estatisticamente significativa. Já os modelos de estimativa de produtividade explicaram 79%, 12% e 74% da variação da produtividade agrícola observada nos talhões nos anos safra 2007/08, 2008/09 e 2009/10, respectivamente, e o modelo considerando as três safras juntas explicou 66%. Esses resultados podem ser usados para auxiliar e aprimorar a estimativa da produtividade feita in loco, e, principalmente, proporcionar uma alternativa ao monitoramento da cultura sob quaisquer condições climáticas / Abstract: The sugarcane (Saccharum spp.) plays important role in economy because it is source of raw material for sugar and alcohol production. In this context the information needs, which enables its monitoring is very important due to allows evaluate the availability of raw material and its demands. For this, it is need a crop systematical monitoring and one of the ways to do this is through the use of remote sensing images. However, it known that it is not always possible due to the rainy season that occurs in certain periods during the crop phenological phases, impeding the acquisition of optics satellite images free of clouds. To get around this problem the use of active sensors, such as sensors of synthetic aperture radar (SAR) can help. SAR sensors can collect data in areas with frequent cloud cover and fog and can operate even at night. Therefore, this study aimed to analyze the potential of radar PALSAR/ALOS, in HH and HV polarizations, for monitoring the sugarcane crop, to determine the effects of planting rows on the backscatter and estimate sugarcane yield by means of model using radar sensor PALSAR/ALOS and agronomic data, in crop seasons: 2007/08, 2008/09, 2009/10 in northeastern region of São Paulo. The results are promising because it was able to show changing in biomass enabling the monitoring. The mean values of the backscattering coefficient (?°) from fields with perpendicular rows, in HH polarization, were higher than those from parallel rows to the range direction of the satellite (0.7 to 2.3 dB over high, 1.2 dB on average). For HV polarization, there was no statistically significant difference. The yield model estimation, explained 79%, 12% and 74% of the variation in final yield, observed in the plots, in crop seasons 2007/08, 2008/09 and 2009/10, respectively, and the model built for the three crop seasons together explained 66% . These results can be used to assist and improve the prediction of yield performed in loco, and mainly to afford an alternative for crop monitoring in some weather conditions / Doutorado / Planejamento e Desenvolvimento Rural Sustentável / Doutora em Engenharia Agrícola
823

Linguistiche analysis van neurogeen stotteren

Bijleveld, Henny January 1999 (has links)
Doctorat en philosophie et lettres / info:eu-repo/semantics/nonPublished
824

Méthodes statistiques pour le calcul d’interférences électromagnétiques extrêmes au sein de systèmes complexes / Statistical methods for the computation of extreme electromagnetic interferences within complex systems

Larbi, Mourad 11 February 2016 (has links)
La prolifération des électroniques et des émetteurs radiofréquences rend de plus en plus compliqué le processus de conception des systèmes sur le plan CEM. Ce processus doit aboutir à limiter le risque d’interférences ou de défauts au niveau le plus faible notamment dans le contexte des interférences électromagnétiques intentionnelles (IEMI). Ces défauts CEM doivent alors être anticipés lors de la phase de conception. Cependant, du fait de la dispersion des valeurs prises par certains paramètres du système, la modélisation déterministe éprouve quelques difficultés à identifier le risque encouru. La mauvaise connaissance de l’effet des incertitudes associées au système, aboutit alors à prendre des marges de conception considérables conduisant à des surcoûts de fabrication. Pour cette raison, il est devenu important de prendre en compte l’impact des incertitudes des différents paramètres constitutifs d’un système (en phase de conception). Ces paramètres sont essentiellement géométriques (e.g. position de câblages) ou électromagnétiques (e.g. caractéristiques intrinsèques de matériaux). Ils influent par nature sur les performances CEM de ce système. Ces travaux de thèse portent sur l’analyse de la propagation des incertitudes relatives à ces paramètres sur des sorties de modèles de CEM. Le but visé, consiste à quantifier sous une forme probabiliste, le risque de défaut d’un système contenant de nombreux paramètres incertains. Ce type d’étude statistique devrait également permettre, via des analyses de sensibilité, des stratégies de conception de systèmes « fiables » ou à moindres coûts. Dans le contexte des applications visées, les approches dites « fiabilistes » et la méthode dite de « stratification contrôlée », ont été identifiées comme intéressantes, du point de vue de l’analyse d’événements extrêmes. Dans un premier temps, nous nous sommes consacrés à la transposition des méthodes fiabilistes dans un contexte CEM. Ces techniques permettent de quantifier la probabilité de défaillance d’un système, définie comme le dépassement d’un seuil de risque, et renseignent, via une analyse de sensibilité locale, sur les paramètres clés à ajuster. Dans un second temps, nous nous sommes intéressés à la méthode de stratification contrôlée, non appliquée à ce jour à notre connaissance en CEM. L’objectif de cette approche consiste à estimer un quantile extrême de la réponse d’intérêt d’un modèle rigoureux, via l’utilisation d’un modèle simple beaucoup moins coûteux en termes de temps de calcul. Ce processus permet d’accélérer l’obtention d’observations extrêmes, nécessaires à l’estimation du quantile recherché. Les deux techniques ont été mises en oeuvre sur un problème complexe dans un contexte IEMI, pour estimer la probabilité d’occurrence d’événements d’interférences extrêmes. Elles ont permis de dégager des tendances similaires, quant à l’importance de certains paramètres d’entrée incertains sur les événements rares. Les deux méthodes, bien appliquées, pourraient constituer un apport considérable en matière de conception CEM. / The proliferation of electronic and radio frequency transmitters makes more complicated the system design process on the EMC point of view. This process should lead to limit the risk of interferences or defects to lowest level particularly in the context of intentional electromagnetic interferences (IEMI). Therefore, these EMC defects have to be anticipated during the design stage. However, due to the dispersion of the values taken by some parameters of the system, the deterministic modeling presents some difficulties to identify the involved risk. The poor knowledge of the uncertainties effect associated with the system, leads then to take important design margins at the price of additional costs of manufacturing. For this reason, it has become important to take into account the impact of uncertainties of the various constituent parameters of a system (at the design stage). These parameters are essentially geometric (e.g. position of wirings) or electromagnetic (e.g. intrinsic characteristics of materials) ones. They influence by nature the EMC performance of this system. This thesis work deals with the analysis of the propagation of uncertainties of these parameters on EMC model outputs. It aims at quantifying in a probabilistic form, the default risk of a system containing numerous uncertain parameters. This type of statistical analysis should also allow through sensitivity analyses, design strategies of “reliable” systems or at lower cost. In the context of targeted applications, the so-called “reliability approaches” and the “controlled stratification” method have been identified as interesting from the point of view of the analysis of extreme events. Firstly, we are dedicated to the transposition of reliability methods in an EMC context. These techniques are used to quantify the probability of failure of a system, defined as the probability of exceeding a threshold of risk. They inform through a local sensitivity analysis, on the key parameters to adjust. Secondly, we have focused our work on the controlled stratification method, not yet applied in EMC as far as we know. The objective of this approach is to estimate an extreme quantile of the interest response of a rigorous model, using of a much cheaper simple model in terms of computation time. This process allows to speed up the identification of extreme observations required for the estimation of the researched quantile. Both techniques have been applied on a complex problem in an IEMI context, to estimate the probability of occurrence of extreme interference events. They have revealed similar trends as regards to the importance of some uncertain input parameters on rare events. Both methods, properly applied, could provide a significant contribution in terms of EMC design strategy.
825

Détermination de classes de modalités de dégradation significatives pour le pronostic et la maintenance / Determination of classes of significant deterioration modalities for prognosis and maintenance

Wang, Xuanzhou 15 November 2013 (has links)
Les travaux présentés dans ce manuscrit traitent de la détermination de classes de systèmes selon leur mode de vieillissement dans l'objectif de prévenir une défaillance et de prendre une décision de maintenance. L’évolution du niveau de dégradation observée sur un système peut être modélisée par un processus stochastique paramétré. Un modèle usuellement utilisé est le processus Gamma. On s’intéresse au cas où tous les systèmes ne vieillissent pas identiquement et le mode de vieillissement est dépendant du contexte d’utilisation des systèmes ou des propriétés des systèmes, appelé ensemble de covariables. Il s’agit alors de regrouper les systèmes vieillissant de façon analogue en tenant compte de la covariable et d’identifier les paramètres du modèle associé à chacune des classes.Dans un premier temps la problématique est explicitée avec notamment la définition des contraintes: incréments d’instants d’observation irréguliers, nombre quelconque d’observations par chemin décrivant une évolution, prise en compte de la covariable. Ensuite des méthodes sont proposées. Elles combinent un critère de vraisemblance dans l’espace des incréments de mesure du niveau de dégradation, et un critère de cohérence dans l’espace de la covariable. Une technique de normalisation est introduite afin de contrôler l’importance de chacun de ces critères. Des études expérimentales sont effectuées pour illustrer l'efficacité des méthodes proposées / The work presented in this thesis deals with the problem of determination of classes of systems according to their aging mode in the aim of preventing a failure and making a decision of maintenance. The evolution of the observed deterioration levels of a system can be modeled by a parameterized stochastic process. A commonly used model is the Gamma process. We are interested in the case where all the systems do not age identically and the aging mode depends on the condition of usage of systems or system properties, called the set of covariates. Then, we aims to group the systems that age similarly by taking into account the covariate and to identify the parameters of the model associated with each class.At first, the problem is presented especially with the definition of constraints: time increments of irregular observations, any number of observations per path which describes an evolution, consideration of the covariate. Then the methods are proposed. They combine a likelihood criterion in the space of the increments of deterioration levels, and a coherence criterion in the space of the covariate. A normalization technique is introduced to control the importance of each of these two criteria. Experimental studies are performed to illustrate the effectiveness of the proposed methods
826

Zadání a statistické řešení výzkumné úlohy / Assignment and Statistical Solution of a Research Task

Novák, Marek January 2008 (has links)
This thesis is intent on the introduction to problems of statistical approach to research tasks. It focuses on research assignments, position of research worker and statistician while analyzing, ways of gathering data files and problems connected with them, main types of multivariate statistical methods and possible views of their classification. Moreover, this work includes overview of examples of research assignments, possibilities of their solutions and related data files. First chapter describes statistical approach to the research assignments, and the second one shows concrete examples of these assignments. The enclosed CD includes data files to most of the statistical examples.
827

Nepřímé metody čtvrtletních odhadů makroagregátů / Indirect methods of quarterly estimates of macroeconomic aggregates

Klučka, Jiří January 2011 (has links)
The aim of my diploma thesis is to describe indirect methods that are used in the compilation of quarterly national accounts. The diploma thesis is divided into three parts and three chapters. The first chapter presents the theoretical background and describes the development of national accounts in the Czech Republic and the basic macroeconomic aggregates. The second chapter is devoted to the quarterly national accounts and mathematical and statistical methods that are used in their compilation. The third chapter describes in detail selected indirect methods, which consists in linking the indicator and aggregate. Consequently, this method is applied to the data of the Czech Republic and then quarterly estimates are constructed which are compared to actual values.
828

O impacto do evento competitivo após o transplante de células-tronco hematopoiéticas : comparação entre os métodos de incidência cumulativa e Kaplan-Meier / The impact of a competitive event after hematopoietic stem cell transplantation : comparison between cumulative incidence and Kaplan-Meier methods

Miranda, Eliana Cristina Martins, 1965 24 August 2018 (has links)
Orientador: Carmino Antonio De Souza / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-24T04:16:36Z (GMT). No. of bitstreams: 1 Miranda_ElianaCristinaMartins_D.pdf: 1801629 bytes, checksum: b4c847d7141a9b207af7438bdef8c791 (MD5) Previous issue date: 2013 / Resumo: O estudo analisa duas metodologias que estão sendo usadas para estimar a probabilidade de eventos. Um método é a inversão do Kaplan-Meier (1-KM), o qual não considera eventos competitivos, e o outro método é a função da incidência cumulativa (FIC). O estudo contemplou a definição do conceito de risco competitivo e a aplicação dos métodos citados em um conjunto de dados de pacientes submetidos ao transplante de células-tronco hematopoiéticas (TCTH). Os critérios de inclusão foram pacientes consecutivos transplantados no período de Janeiro de 1994 a Dezembro de 2010, com diagnóstico de leucemia aguda (LA) ou leucemia mieloide crônica (LMC). O evento de interesse foi a doença do enxerto contra o hospedeiro (DeCH) crônica, enquanto os eventos competitivos foram: recaída e morte prévia a DeCH crônica. O resultado após a aplicação do método 1-KM para o grupo de pacientes com LA foi de 52% e estratificado pelo tipo de enxerto foi 44% para medula óssea (MO) e 77% para sangue periférico (SP) p= 0.003. Quando aplicado o método FIC a probabilidade geral foi de 45% e por tipo de enxerto foi 17% para MO e 33% para SP, p= 0.00002. No grupo de pacientes diagnosticados com LMC, usando a mesma racional os resultados foram similares. Não há comparações entre os métodos estatísticos, principalmente porque o pressuposto de se considerar o evento competitivo é aplicado somente na metodologia FIC. A fonte de células SP cotejada com fonte de células MO conduzem a uma incidência cumulativa maior de DeCH, independente da doença de base. Os resultados apresentaram, na grande maioria, diferenças grandes entre os testes, indicando a importância de se averiguar os detalhes no momento da aplicação / Abstract: This study presents two methodologies that have been used to estimate the probability of events. One method is the Kaplan-Meier inversion (1-KM), which no consider the competitive events, and another one is the cumulative incidence function (CIF). The study showed the definition of competitive risk concepts and its application in the database of patients submitted to the hematopoietic stem cell transplantation (HSCT). Inclusion criteria were consecutive transplanted patients in the period between January 1994 to December 2010, with acute leukemia (AL) or chronic myeloid leukemia (CML). The interest event was chronic graft versus host disease (GVHD), insofar, competitive events were relapse or early death previous to chronic GVHD. The results after 1-KM application in the AL group was 52% and stratified by source of graft was 44% in bone marrow (BM) and 77% in peripheral blood (PB) with p=0.003. When CIF test applied the results was 45% and by source of graft was 17% in BM and 33% in PB, p= 0.00002. In the CML group the results were similar. There is no comparison between the statistical tests, mainly because their assumptions are not the same. PB as source of graft induces a higher incidence of chronic GVHD, independent of disease. All results presented, in the mayor, huge differences among the tests, indicating the importance to check the details at time of application / Doutorado / Clinica Medica / Doutora em Clínica Médica
829

Avaliação da qualidade das águas na sub-bacia hidrográfica do Rio Siriri/SE

Gonçalves, Amanda de Azevedo 26 February 2016 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The sub-basin of the river Siriri stands out for its diversity in land use and soil, having: agricultural activity, with planting of sugarcane and pasture; industrial, producing fertilizers and agro-energy; and urban areas. Also in the study area are perceived visual impacts, such as the removal of riparian vegetation along the river and around the springs reflecting the environmental quality loss; advanced erosion stage in some reaches; sediment banks in bed; odor and the presence of solid waste in dried periods. This study aims to evaluate the quality of surface waters in the watershed of the Rio Siriri by collecting water samples, laboratory tests and statistical tools, in order to contribute to the understanding of its seasonal variation. Thus, to characterize the water quality of the river Siriri were selected five points for the collection of water samples. This research used some statistical tools, such as the descriptive statistics applied to twelve variables: T, pH, DO, N, NO-3, P, chlorophyll-a, PRD, TDS, turbidity, EC and TTC; and the correlation matrix tool; analysis of variance and principal component analysis. The survey showed that DO is on alert for noble uses in this basin in study. P is not within the limit of CONAMA Resolution 357/2005 for Class 1, but within the limit for Class 2, but on alert. There is a negative correlation between the variable agriculture area with the DO and positively with EC, turbidity and P. In the ANOVA analyses, there was significant difference (at 5% level of significance) to the location factor for the variables pH, EC, TDS, DO, turbidity, N, P, TTC, depth, agriculture and pasture. For seasonality factor it was observed significant difference for T, NO-3, N, P, PRD, turbidity, chlorophyll-a and precipitation. By PCA with Varimax rotation, the PC1 (27%) concentrated the variables related to the influence of agricultural activities (EC, TDS, DO, P, agriculture and pasture). It was observed that the point P1 contributed to the variations of N, NO-3 and DO. / A sub-bacia hidrográfica do rio Siriri destaca-se por sua diversidade no uso da terra e do solo, possuindo: atividade agropecuária, com plantio de cana-de-açúcar e pastagens; industrial, com produção de fertilizantes e agroenergia; e, zonas urbanas. Também na área em estudo percebem-se impactos visuais, como: a supressão da mata ciliar ao longo do rio e no entorno das nascentes refletindo na perda da qualidade ambiental; trechos em estágio de erosão avançada; bancos de sedimentos no leito; odor em períodos secos e presença de resíduos sólidos. O presente trabalho tem como objetivo avaliar a qualidade das águas superficiais na sub-bacia hidrográfica do Rio Siriri por meio de coletas de amostras de água, testes laboratoriais e ferramentas estatísticas, buscando contribuir para o entendimento da sua variação sazonal. Dessa forma, para caracterizar a qualidade da água do rio Siriri foram selecionados cinco pontos para a coleta de amostras de água. Essa pesquisa utilizou algumas ferramentas estatísticas, tais como a estatística descritiva aplicada nas doze variáveis: T, pH, OD, N, NO-3, P, clorofila-a, PRD, SDT, turbidez, CE e CTT; a ferramenta matriz de correlação; a análise de variância e a ferramenta para análise de componentes principais. A pesquisa mostrou que o OD encontra-se em estado de alerta para usos nobres na sub-bacia hidrográfica em estudo. O P não está dentro do limite da Resolução CONAMA 357/2005 para Classe 1 e sim dentro do limite para Classe 2, porém em estado de alerta. Há correlação da variável agricultura negativamente com o OD e positivamente com CE, Turbidez e P. Na análise da ANOVA houve diferença significativa (ao nível de 5% de significância) para o fator localização para as variáveis pH, CE, SDT, OD, turbidez, N, P, CTT, profundidade, agricultura e pastagem. Para sazonalidade, verificou-se diferença significativa para T, NO-3, N, P, PRD, turbidez, clorofila-a e para as precipitações. Por PCA com rotação Varimax, o PC1 (27%) concentrou-se as variáveis relacionadas à influência de atividades agrícolas (CE, SDT, OD, P, agricultura e pastagem). Observou-se que o ponto P1 contribuiu para as variações de N, NO-3 e OD.
830

Análise qualitativa de um modelo de propagação de dengue para populações espacialmente homogêneas / Qualitative analysis of dengue propagation model to spatially homogeneous populations

Sales Filho, Nazime, 1986- 26 August 2018 (has links)
Orientador: Bianca Morelli Rodolfo Calsavara / Dissertação (mestrado profissional) - Universidade Estadual de Campinas, Instituto de Matemática, Estatística e Computação Científica / Made available in DSpace on 2018-08-26T15:10:31Z (GMT). No. of bitstreams: 1 SalesFilho_Nazime_M.pdf: 36937949 bytes, checksum: 4ceff2992bbc8648a89104715aac602e (MD5) Previous issue date: 2015 / Resumo: Neste trabalho será analisado um modelo matemático que descreve a propagação da dengue. Tal modelo é dado por um sistema de equações diferenciais ordinárias não lineares sujeitas a condições iniciais, que descreve duas populações: a de mosquitos e a humana. A população de mosquitos é dividida em duas subpopulações: fase aquática, incluindo os ovos, larvas e pupas, e fase alada, que é subdividida em mosquitos suscetíveis e infectados. A população humana é dividida em subpopulações de suscetíveis, infectados e removidos. No modelo citado é assumido que a população de mosquito e a população humana atingiram homogeneidade espacial, isto é, não há movimentação destas populações influenciando na disseminação da doença. O principal interesse neste trabalho é analisar qualitativamente o comportamento das populações em torno dos pontos de equilíbrio do sistema. Para este fim, além do uso de ferramentas analíticas também foram realizadas simulações numéricas utilizando o software Maple. Dessa forma foi possível obter informações sobre a disseminação da dengue, sob algumas hipóteses, mesmo sem obtermos solução explícita do sistema / Abstract: In this work it will be analyzed a mathematical model describing propagation of dengue disease. This model is given by a system of nonlinear ordinary differential equations, subjected to initial conditions, involving two populations: one of mosquitos and another of humans. The mosquitos population is divided in two subpopulations: the aquatic phase, including eggs, larvae and pupae, and the winged phase, that is divided in susceptible and infected mosquitos. The human population is divided in subpopulations of susceptible, infected and removed. In the cited model it is assumed that the mosquito and human populations achieved spatial homogeneity, i.e., there is no movement of these populations affecting the disease dissemination. The main interest of this work is to analyze qualitatively the populations behavior around the equilibrium points of the system. To this end, in addition to the use of analytical tools, numerical simulations were performed by using Maple software. In this way, it was possible to obtain information about dengue dissemination, under some hypotheses, even without obtaining explicit solution for the system / Mestrado / Matematica Aplicada e Computacional / Mestre em Matemática Aplicada e Computacional

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