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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.
71

Katenoidų uždavinys variaciniame skaičiavime / The catenoid problem in the variational calculus

Michnevič, Viktorija 22 July 2014 (has links)
Magistro darbe nagrinėjamas katenoidų uždavinys, kuris sprendžiamas variaciniu metodu. Ištirta, kada egzistuoja šio uždavinio sprendinys su simetrinėmis kraštinėmis sąlygomis: y(-a)=y=(a)=A>0. Ištirti atvejai, kai uždavinys neturi sprendinio glodžių funkcijų klasėje. Ištirta, kada egzistuoja šio uždavinio sprendinys su nesimetrinėmis kraštinėmis sąlygomis y(a)=A, y(b)=B, A≠B. Uždavinys buvo sprendžiamas kompiuterinės programos Maple pagalba. / In this master thesis the catenoid problem is discussed using the variational methods. The existence of the solution in the case of symmetrical boundary value conditions y(-a)=y=(a)=A>0 is established. An example is given in the case, when catenoid problem doesn’t have any solution in the class of smooth functions. Besides, an example of this variational problem with non-symmetrical boundary value conditions of the type y(a)=A, y(b)=B, A≠B, is considered. All problems were solved using technical computing sofware Maple.
72

Climate variability and change impacts on coastal environmental variables in British Columbia, Canada

Abeysirigunawardena, Dilumie Saumedaka 29 April 2010 (has links)
The research presented in this dissertation attempted to determine whether climate variability is critical to sea level changes in coastal BC. To that end, a number of statistical models were proposed to clarify the relationships between five climate variability indices representing large-scale atmospheric circulation regimes and sea levels, storm surges, extreme winds and storm track variability in coastal BC. The research findings demonstrate that decadal to inter decadal climatic variability is fundamental to explaining the changing frequency and intensity of extreme atmospheric and oceanic environmental variables in coastal BC. The trends revealed by these analyses suggest that coastal flooding risks are certain to increase in this region during the next few decades, especially if the global sea-levels continue to rise as predicted. The out come of this study emphasis the need to look beyond climatic means when completing climate impact assessments, by clearly showing that climate extremes are currently causing the majority of weather-related damage along coastal BC. The findings highlight the need to derive knowledge on climate variability and change effects relevant at regional to local scales to enable useful adaptation strategies. The major findings of this research resulted in five independent manuscripts: (i) Sea level responses to climatic variability and change in Northern BC. The Manuscript (MC) is published in the Journal of atmospheric and oceans (AO 46 (3), 277-296); (ii) Extreme sea-level recurrences in the south coast of BC with climate considerations. This MC is in review with the Asia Pacific Journal of Climate Change (APJCC); (iii) Extreme sea-surge responses to climate variability in coastal BC. This MC is currently in review in the Annals of the AAG (AN-2009-0098); (iv) Extreme wind regime responses to climate variability and change in the inner-south-coast of BC. This MC is published in the Journal of Atmosphere and Oceans (AO 47 (1), 41-62); (v) Sensitivity of winter storm track characteristics in North-eastern Pacific to climate variability. This manuscript is in review with the Journal of Atmosphere and Oceans (AO (1113)). The findings of this research program made key contributions to the following regional sea level rise impact assessment studies in BC: (i) An examination of the Factors Affecting Relative and Absolute Sea level in coastal BC (Thomson et al., 2008). (ii) Coastal vulnerability to climate change and sea level rise, Northeast Graham Island, Haida Gwaii (formally known as the Queen Charlotte Islands), BC (Walker et al., 2007). (iii) Storm Surge: Atmospheric Hazards, Canadian Atmospheric Hazards Network - Pacific and Yukon Region, C/O Bill Taylor.
73

Théorèmes limites pour des fonctionnelles de clusters d'extrêmes et applications / Limit theorems for functionals of clusters of extremes and applications

Gomez Garcia, José Gregorio 13 November 2017 (has links)
Cette thèse traite principalement des théorèmes limites pour les processus empiriques de fonctionnelles de clusters d'extrêmes de séquences et champs aléatoires faiblement dépendants. Des théorèmes limites pour les processus empiriques de fonctionnelles de clusters d'extrême de séries temporelles stationnaires sont donnés par Drees & Rootzén [2010] sous des conditions de régularité absolue (ou "ß-mélange"). Cependant, ces conditions de dépendance de type mélange sont très restrictives : elles sont particulièrement adaptées aux modèles dans la finance et dans l'histoire, et elles sont de plus compliquées à vérifier. Généralement, pour d'autres modèles fréquemment rencontré dans les domaines applicatifs, les conditions de mélange ne sont pas satisfaites. En revanche, les conditions de dépendance faible, selon Doukhan and Louhichi [1999] et Dedecker & Prieur [2004a], sont des conditions qui généralisent les notions de mélange et d'association. Elles sont plus simple à vérifier et peuvent être satisfaites pour de nombreux modèles. Plus précisément, sous des conditions faibles, tous les processus causals ou non causals sont faiblement dépendants: les processus Gaussien, associés, linéaires, ARCH(∞), bilinéaires et notamment Volterra entrent dans cette liste. À partir de ces conditions favorables, nous étendons certains des théorèmes limites de Drees & Rootzén [2010] à processus faiblement dépendants. En outre, comme application des théorèmes précédents, nous montrons la convergence en loi de l'estimateur de l'extremogramme de Davis & Mikosch [2009] et l'estimateur fonctionnel de l'indice extrémal de Drees [2011] sous dépendance faible. Nous démontrons un théorème de la valeur extrême pour les champs aléatoires stationnaires faiblement dépendants et nous proposons, sous les mêmes conditions, un critère du domaine d'attraction d'une loi d'extrêmes. Le document se conclue sur des théorèmes limites pour les processus empiriques de fonctionnelles de clusters d’extrêmes de champs aléatoires stationnaires faiblement dépendants, et met en évidence la convergence en loi de l'estimateur d'un extremogramme de processus spatio-temporels stationnaires faiblement dépendants en tant qu'application. / This thesis deals mainly with limit theorems for empirical processes of extreme cluster functionals of weakly dependent random fields and sequences. Limit theorems for empirical processes of extreme cluster functionals of stationnary time series are given by Drees & Rootzén [2010] under absolute regularity (or "ß-mixing") conditions. However, these dependence conditions of mixing type are very restrictive: on the one hand, they are best suited for models in finance and history, and on the other hand, they are difficult to verify. Generally, for other models common in applications, the mixing conditions are not satisfied. In contrast, weak dependence conditions, as defined by Doukhan & Louhichi [1999] and Dedecker & Prieur [2004a], are dependence conditions which generalises the notions of mixing and association. These are easier to verify and applicable to a wide list of models. More precisely, under weak conditions, all the causal or non-causal processes are weakly dependent: Gaussian, associated, linear, ARCH(∞), bilinear and Volterra processes are some included in this list. Under these conveniences, we expand some of the limit theorems of Drees & Rootzén [2010] to weakly dependent processes. These latter results are used in order to show the convergence in distribution of the extremogram estimator of Davis & Mikosch [2009] and the functional estimator of the extremal index introduced by Drees [2011] under weak dependence. We prove an extreme value theorem for weakly dependent stationary random fields and we propose, under the same conditions, a domain of attraction criteria of a law of extremes. The document ends with limit theorems for the empirical process of extreme cluster functionals of stationary weakly dependent random fields, deriving also the convergence in distribution of the estimator of an extremogram for stationary weakly dependent space-time processes.
74

Deslizamentos de terra no município de Nova Friburgo: histórico e interpretação estatística de dados / Landslides in municipal area of Nova Friburgo: historical and data statistical interpretation

Celso Narcizo Volotão 29 June 2006 (has links)
Uma modelagem estatística baseada no conceito "risco = probabilidade x conseqüência" e no principio da máxima entropia é apresentada nesta Dissertação, visando estabelecer previsões realistas de perda de vida no Município de Nova Friburgo, Estado do Rio de Janeiro, para subsidiar as autoridades públicas locais a minimizar as conseqüências de inundações e deslizamentos de terra. Os resultados mostram que o princípio da máxima entropia modela muito bem a distribuição de mortalidade em deslizamentos de terra. Comparações de mortalidade em Nova Friburgo, Petrópolis, Região Metropolitana de Recife e na Cidade do Rio de Janeiro também são apresentadas nesta Dissertação. Os resultados apresentados indicam que o risco de perda de vidas em Nova Friburgo é de, aproximadamente, a terça parte do risco em Petrópolis ou a quarta parte do risco na Cidade do Rio de Janeiro. Um estudo estatístico dos deslizamentos registrados na Rodovia RJ-116, no trecho de serra entre as cidades de Nova Friburgo e Cachoeiras de Macacu, mostra também um bom ajuste dos dados históricos com o princípio de máxima entropia, apesar do curto período de observação, de apenas 21 meses. As previsões baseadas no princípio de máxima entropia indicam que a Defesa Civil municipal deveria estar preparada para atuar de forma planejada em um evento extremo com possibilidade de ocorrência de até 27 casos fatais, no caso de uma chuva excepcionalmente elevada. / A statistical model based on the concept risk = probability x consequence and on the principle of maximum entropy is presented in this Dissertation, aiming to establish realistic predictions of loss of life in the Municipal area of Nova Friburgo State of Rio de Janeiro, to help the local public authorities to minimize the consequences of flooding and landslide. The results show that the principle of maximum entropy models very well the distribution of mortality in landslide disasters. Comparisons of landslide mortality in Nova Friburgo, Petrópolis, and Metropolitan Area of Recife and in the City of Rio de Janeiro are presented in this Dissertation. The results shown indicate that the risk of loss life in Nova Friburgo is about one third of the risk in Petrópolis and about one forth of risk in the Rio de Janeiro City. A statistical study of the recorded landslides in the Highway RJ-116, in the mountain area between Nova Friburgo and Cachoeiras de Macacu cities, shows also a good adjustment of the historical data with the principle of maximum entropy in spite of the short period of observation, only 21 months. Predictions based on the principle of maximum entropy indicate that the Municipal Civil Defense should be prepared to face a landslide disaster with as much as 27 fatal cases in case of a exceptionally high rainfall.
75

VARIAÇÕES CLIMÁTICAS NA PRECIPITAÇÃO DO RIO GRANDE DO SUL NO CLIMA PRESENTE E FUTURO / CLIMATE CHANGE IN PRECIPITATION IN SOUTHERN BRAZIL IN PRESENT AND FUTURE CLIMATE

Cera, Jossana Ceolin 17 March 2011 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / This study presents the analysis of precipitation trends for the Southern region of Brazil, for three present climate periods with a comparison between precipitation data and data of the regional Model RegCM3 and an analysis of future climate tendency. The study also presents the pattern of precipitation variability which operates in the South region o f Brazil. Using the Principal Components Analysis for daily precipitation data filtered in 2/20 day band, 20/100 day band and interannual band, spatial and temporal fields were found which represent the maximum variance of certain variabilities and in these, the variability pattern of precipitation for each season. And with the standard deviation series it was possible to determine the quantity of dry and rainy events present in each variability pattern. The pattern were calculated in three periods: from 1981 to 2007 for the precipitation data by Dr. Liebmann, from 1982 to 2006 for the data of the RegCM3 Model and from 2070 to 2086 for the data of the Model for future climate, being the A2 the scenery for emission used for the last period (considered pessimist). Three variability pattern were found, they were denominated Modo Sul, Modo PR and Modo Niño. / Este trabalho apresenta a análise de tendências de precipitação para a região Sul do Brasil, para três conjuntos de dados com uma comparação entre dados de precipitação e dados do Modelo regional RegCM3 e uma análise de tendência para o clima futuro. O trabalho também apresenta os modos de variabilidade de precipitação que atuam na região Sul do Brasil. Utilizando a análise de componentes principais em dados de precipitação diária filtrados nas bandas 2/20 dias, 20/100 dias e banda interanual foram encontrados campos espaciais e temporais que representam a máxima variância de determinadas variabilidades, e neles foram detectados os modos de variabilidade de precipitação para cada estação do ano. E com as séries de desvio padrão foi possível determinar a quantidade de eventos secos e chuvosos presentes em cada modo de variabilidade. Os modos foram calculados para três períodos: de 1981 a 2007 para os dados de precipitação do Dr. Liebmann, de 1982 a 2006 para os dados do Modelo RegCM3 e de 2070 a 2086 para os dados do Modelo para o clima futuro, sendo que o cenário de emissão utilizado para este ultimo período foi o A2 (considerado pessimista). Foram encontrados três modos de variabilidade denominados Modo Sul, Modo PR e Modo Niño.
76

Contributions à la théorie des valeurs extrêmes : Détection de tendance pour les extrêmes hétéroscédastiques / Contributions to extreme value theory : Trend detection for heteroscedastic extremes

Mefleh, Aline 26 June 2018 (has links)
Nous présentons dans cette thèse en premier lieu la méthode de Bootstrap par permutation appliquée à la méthode des blocs maxima utilisée en théorie des valeurs extrêmes (TVE) univariée. La méthode est basée sur un échantillonnage particulier des données en utilisant les rangs des blocs maxima dont la distribution est présentée et introduite dans les simulations. Elle amène à une réduction de la variance des paramètres de la loi GEV et des quantiles estimés. En second lieu, on s’intéresse au cas où les observations sont indépendantes mais non identiquement distribuées en TVE. Cette variation dans la distribution est quantifiée en utilisant une fonction dite « skedasis function » notée c qui représente la fréquence des extrêmes. Ce modèle a été introduit par Einmahl et al. dans le papier « Statistics of heteroscedastic extremes ». On étudie plusieurs modèles paramétriques pour c (log-linéaire, linéaire, log-linéaire discret) ainsi que les résultats de consistance et de normalité asymptotique du paramètre θ représentant la tendance. Le test θ =0 contre θ ≠0 est interprété alors comme un test de détection de tendance dans les extrêmes. Nous illustrons nos résultats dans une étude par simulation qui montre en particulier que les tests paramétriques sont en général plus puissants que les tests non paramétriques pour la détection de la tendance, d’où l’utilité de notre travail. Nous discutons en plus le choix du seuil k en appliquant la méthode de Lepski. Enfin, nous appliquons la méthodologie sur les données de températures minimales et maximales dans la région de Fort Collins, Colorado durant le 20ème siècle afin de détecter la présence d’une tendance dans les extrêmes sur cette période. En troisième lieu, on dispose d’un jeu de données de précipitation journalière maximale sur 24 ans dans 40 stations. On réalise une prédiction spatio-temporelle des quantiles correspondants à un niveau de retour de 20 ans pour les précipitations mensuelles dans chaque station. Nous utilisons des modèles de GEV en introduisant des covariables dans les paramètres. Le meilleur modèle est choisi en termes d’AIC et par la méthode de validation croisée. Pour chacun des deux modèles choisis, nous estimons les quantiles extrêmes. Finalement, on applique la TVE unvariée et bivariée sur les vitesses du vent et la hauteur des vagues dans une région au Liban en vue de protéger la plateforme pétrolière qui y sera installée de ces risques environnementaux. On applique d’abord la théorie univariée sur la vitesse du vent et la hauteur des vagues séparément en utilisant la méthode des blocs maximas pour estimer les paramètres de la GEV et les niveaux de retour associés à des périodes de retour de 50, 100 et 500 années. Nous passons ensuite à l’application de la théorie bivariée afin d’estimer la dépendance entre les vents et les vagues extrêmes et d’estimer des probabilités jointes de dépassement des niveaux de retour univariés. Nous associons ces probabilités jointes de dépassement à des périodes de retour jointes et nous les comparons aux périodes de retour marginales. / We firstly present in this thesis the permutation Bootstrap method applied for the block maxima (BM) method in extreme value theory. The method is based on BM ranks whose distribution is presented and simulated. It performs well and leads to a variance reduction in the estimation of the GEV parameters and the extreme quantiles. Secondly, we build upon the heteroscedastic extremes framework by Einmahl et al. (2016) where the observations are assumed independent but not identically distributed and the variation in their tail distributions is modeled by the so-called skedasis function. While the original paper focuses on non-parametric estimation of the skedasis function, we consider here parametric models and prove the consistency and asymptotic normality of the parameter estimators. A parametric test for trend detection in the case where the skedasis function is monotone is introduced. A short simulation study shows that the parametric test can be more powerful than the non-parametric Kolmogorov-Smirnov type test, even for misspecified models. We also discuss the choice of threshold based on Lepski's method. The methodology is finally illustrated on a dataset of minimal/maximal daily temperatures in Fort Collins, Colorado, during the 20th century. Thirdly, we have a training sample data of daily maxima precipitation over 24 years in 40 stations. We make spatio-temporal prediction of quantile of level corresponding to extreme monthly precipitation over the next 20 years in every station. We use generalized extreme value models by incorporating covariates. After selecting the best model based on the Akaike information criterion and the k-fold cross validation method, we present the results of the estimated quantiles for the selected models. Finally, we study the wind speed and wave height risks in Beddawi region in the northern Lebanon during the winter season in order to protect the oil rig that will be installed. We estimate the return levels associated to return periods of 50, 100 and 500 years for each risk separately using the univariate extreme value theory. Then, by using the multivariate extreme value theory we estimate the dependence between extreme wind speed and wave height as well as joint exceedance probabilities and joint return levels to take into consideration the risk of these two environmental factors simultaneously.
77

Estudo estat?stico sobre eventos de precipita??o intensa no nordeste do Brasil / Statistical analysis of the extreme rainfall events in northeastern Brazil

Oliveira, Priscilla Teles de 16 April 2014 (has links)
Made available in DSpace on 2014-12-17T14:12:03Z (GMT). No. of bitstreams: 1 PriscillaTO_TESE.pdf: 3493221 bytes, checksum: 724431c57caf371626a1f4eb15f4b92c (MD5) Previous issue date: 2014-04-16 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The Northeast of Brazil (NEB) shows high climate variability, ranging from semiarid regions to a rainy regions. According to the latest report of the Intergovernmental Panel on Climate Change, the NEB is highly susceptible to climate change, and also heavy rainfall events (HRE). However, few climatology studies about these episodes were performed, thus the objective main research is to compute the climatology and trend of the episodes number and the daily rainfall rate associated with HRE in the NEB and its climatologically homogeneous sub regions; relate them to the weak rainfall events and normal rainfall events. The daily rainfall data of the hydrometeorological network managed by the Ag?ncia Nacional de ?guas, from 1972 to 2002. For selection of rainfall events used the technique of quantiles and the trend was identified using the Mann-Kendall test. The sub regions were obtained by cluster analysis, using as similarity measure the Euclidean distance and Ward agglomerative hierarchical method. The results show that the seasonality of the NEB is being intensified, i.e., the dry season is becoming drier and wet season getting wet. The El Ni?o and La Ni?a influence more on the amount of events regarding the intensity, but the sub-regions this influence is less noticeable. Using daily data reanalysis ERAInterim fields of anomalies of the composites of meteorological variables were calculated for the coast of the NEB, to characterize the synoptic environment. The Upper-level cyclonic vortex and the South atlantic convergene zone were identified as the main weather systems responsible for training of EPI on the coastland / O Nordeste do Brasil (NEB) apresenta alta variabilidade no clima, abrangendo desde regi?es semi-?ridas at? regi?es com alto ?ndice pluviom?trico. Segundo o ?ltimo relat?rio do Intergovernmental Panel on Climate Change, o NEB ? uma regi?o altamente suscept?vel ?s mudan?as clim?ticas, al?m de ser uma regi?o sujeita ? ocorr?ncia de eventos de precipita??o intensa (EPI); contudo, ainda existem poucos estudos sobre a climatologia destes epis?dios na regi?o. Neste sentido, o objetivo principal da pesquisa ? determinar a climatologia e tend?ncia dos EPI sobre o NEB e suas sub-regi?es climatologicamente homog?neas, comparando seu comportamento com a climatologia e tend?ncia dos eventos de precipita??o fraca e dos eventos de precipita??o normal. Para tanto, foram utilizados os dados di?rios de precipita??o da rede hidrometeorol?gica gerenciada pela Ag?ncia Nacional de ?guas, para o per?odo de 1972 a 2002. Por interm?dio da t?cnica dos quantis foram definidos os eventos de precipita??o e sua confian?a estat?stica foi analisada atrav?s do teste de Mann Kendall. As sub-regi?es foram obtidas por meio da an?lise de cluster, utilizando como medida de similaridade a dist?ncia euclidiana e o m?todo hier?rquico aglomerativo de Ward. Os resultados mostraram que a sazonalidade do NEB est? sendo intensificada, ou seja, a esta??o seca est? se tornando mais seca e esta??o chuvosa ficando mais chuvosa. Os fen?menos El Ni?o e La Ni?a influenciam mais em rela??o ? quantidade de eventos do que em rela??o ? intensidade, mas nas sub-regi?es esta influ?ncia ? menos percept?vel. Utilizando dados di?rios das rean?lises do ERA-Interim, campos das anomalias dos compostos de vari?veis meteorol?gicas foram calculados para o litoral do NEB, para caracteriza??o do ambiente sin?tico. Foram identificados os V?rtices Cicl?nicos de Altos N?veis e a Zona de Converg?ncia do Atl?ntico Sul como os principais sistemas meteorol?gicos respons?veis pela forma??o dos EPI no litoral
78

Deslizamentos de terra no município de Nova Friburgo: histórico e interpretação estatística de dados / Landslides in municipal area of Nova Friburgo: historical and data statistical interpretation

Celso Narcizo Volotão 29 June 2006 (has links)
Uma modelagem estatística baseada no conceito "risco = probabilidade x conseqüência" e no principio da máxima entropia é apresentada nesta Dissertação, visando estabelecer previsões realistas de perda de vida no Município de Nova Friburgo, Estado do Rio de Janeiro, para subsidiar as autoridades públicas locais a minimizar as conseqüências de inundações e deslizamentos de terra. Os resultados mostram que o princípio da máxima entropia modela muito bem a distribuição de mortalidade em deslizamentos de terra. Comparações de mortalidade em Nova Friburgo, Petrópolis, Região Metropolitana de Recife e na Cidade do Rio de Janeiro também são apresentadas nesta Dissertação. Os resultados apresentados indicam que o risco de perda de vidas em Nova Friburgo é de, aproximadamente, a terça parte do risco em Petrópolis ou a quarta parte do risco na Cidade do Rio de Janeiro. Um estudo estatístico dos deslizamentos registrados na Rodovia RJ-116, no trecho de serra entre as cidades de Nova Friburgo e Cachoeiras de Macacu, mostra também um bom ajuste dos dados históricos com o princípio de máxima entropia, apesar do curto período de observação, de apenas 21 meses. As previsões baseadas no princípio de máxima entropia indicam que a Defesa Civil municipal deveria estar preparada para atuar de forma planejada em um evento extremo com possibilidade de ocorrência de até 27 casos fatais, no caso de uma chuva excepcionalmente elevada. / A statistical model based on the concept risk = probability x consequence and on the principle of maximum entropy is presented in this Dissertation, aiming to establish realistic predictions of loss of life in the Municipal area of Nova Friburgo State of Rio de Janeiro, to help the local public authorities to minimize the consequences of flooding and landslide. The results show that the principle of maximum entropy models very well the distribution of mortality in landslide disasters. Comparisons of landslide mortality in Nova Friburgo, Petrópolis, and Metropolitan Area of Recife and in the City of Rio de Janeiro are presented in this Dissertation. The results shown indicate that the risk of loss life in Nova Friburgo is about one third of the risk in Petrópolis and about one forth of risk in the Rio de Janeiro City. A statistical study of the recorded landslides in the Highway RJ-116, in the mountain area between Nova Friburgo and Cachoeiras de Macacu cities, shows also a good adjustment of the historical data with the principle of maximum entropy in spite of the short period of observation, only 21 months. Predictions based on the principle of maximum entropy indicate that the Municipal Civil Defense should be prepared to face a landslide disaster with as much as 27 fatal cases in case of a exceptionally high rainfall.
79

Eventos pluviais extremos e risco de inundações na cidade de Aracaju/SE

Brazil, João Luiz Santana 31 May 2016 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The disorderly growth of cities has caused a continuous process of environmental degradation in urban centers, providing a setting for risks caused by climatic factors. It is in this context that, from the 70s, the city of Aracaju has grown considerably. The process of occupation of environmentally fragile areas, for socially vulnerable populations is critical to the formation of areas of risk, exposed to more intense rainfall events. This research aims to analyze the extreme rainfall events in the areas of risk to flooding from the urban development of the city of Aracaju / SE. To achieve the proposed objectives was made using different procedures, emphasizing the theoretical review, covering theory and urban climate, cartographic survey and field work to show and record the areas at risk of flooding. The methodology allowed the crossing of social and environmental variables to identify the level of risk to flooding. The results achieved in this research led to the acceptance of the rain is the main cause of the risk of formation to flooding in Aracaju / SE, but that comes from overlapping with the pace of urbanization in the city. In addition, the study also demonstrated that an adequate sanitation service, if the urban drainage service contributes directly to improving the health of the population. The risk to flooding can be analyzed and verified in comparison of existing typological patterns in Aracaju in 2004, compared to the current typological standards in 2014. The city is another and their relationships as well. Thus, the extreme rainfall events that occur in the city of Aracaju occur in the autumn and winter period, between the months of March to July, and cause the exposure condition of the risk to the resident, varies according to their socioeconomic standard population / O crescimento desordenado das cidades tem causado um contínuo processo de degradação ambiental nos centros urbanos, propiciando um cenário para riscos causados pelos fatores climáticos. É nesse contexto que, a partir da década de 70, a cidade de Aracaju cresceu consideravelmente. O processo de ocupação de áreas ambientalmente frágeis, por populações socialmente vulneráveis, é decisivo para a formação de espaços de riscos, mais expostos a eventos pluviais intensos. Esta pesquisa tem como objetivo analisar os eventos pluviais extremos nas áreas de risco à inundações a partir do desenvolvimento urbano da cidade de Aracaju/SE. Para o alcance dos objetivos propostos fez-se uso de procedimentos distintos, priorizando a revisão teórica, levantamento cartográfico e trabalho em campo para evidenciar e registrar as áreas de risco de inundações. A metodologia utilizada permitiu o cruzamento das variáveis socioambientais para identificação do nível de risco a inundações. Os resultados alcançados nesta pesquisa conduziram para a aceitação de que a chuva é a principal causa da formação de risco a inundações em Aracaju/SE, mas que advém das imbricações com os ritmos da urbanização na cidade. Além disso, o estudo demonstrou ainda que um serviço de saneamento adequado, no caso o serviço de drenagem urbana contribui diretamente para a melhoria da qualidade de vida da população. O risco a inundações pode ser analisado e constatado em comparativos dos padrões tipológicos preexistentes em Aracaju em 2004, frente aos atuais padrões tipológicos em 2014. A cidade é outra e suas relações também. Assim, os eventos pluviais extremos que registrados na cidade de Aracaju estão concentradas no período de outono e inverno, entre os meses de março a julho, e ocasionam a condição de exposição a riscos para a população residente, variável conforme seu padrão socioeconômico. Conclui-se, portanto, que para que as políticas públicas sejam eficazes, é fundamental que as autoridades públicas considerem as peculiaridades e particularidades naturais da cidade de Aracaju, remanejando as pessoas das áreas propensas às inundações, além de garantir investimentos na educação ambiental, visando diminuir a quantidade de despejo de lixo nos rios e buscar soluções de engenharia mais adequadas.
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Sistema de alerta inteligente para apoiar a comunicação e a mobilização de equipes de emergência na Amazônia

Nogueira, André Alves 20 February 2014 (has links)
Made available in DSpace on 2015-04-11T14:02:58Z (GMT). No. of bitstreams: 1 Andre Alves Nogueira.pdf: 3385945 bytes, checksum: 5c7b555b59610b2dac767f2900bfe5be (MD5) Previous issue date: 2014-02-20 / Weather Extreme Events (WEE) can cause natural disasters because they are often accompanied by dangerous physical activities which cause significant damage to people and properties, including some deaths. A way to soften the damage caused by these disasters is to use Weather Warning System (WWS). These kind of systems can detect an imminent risk and, different types of alerts can be triggered in order to mobilize the emergency personnel in advance. This research aims to help the Amazon Protection System (SIPAM) to solve the communication problem with the alert and mobilization. It is intended, primarily, to assist the Civil Defense with the affected population by WEE. A comparative investigation was performed in ten studies aiming to understand and analyze the main characteristics of a Warning System, which were incorporated into this research, highlighting the support of a Multi-Agent System to assist the WWS, and the use of SMS (Short Message Service) technology and E-mail for sending the alert. System Tests showed that the approach proved promising, with shipping times smaller alerts those found in the literature with a high rate of confirmed users. Also the process of sending the alert factor being faster helps to minimize the effects of EME with the affected population. / Eventos Meteorológicos Extremos (EME) podem gerar desastres naturais, geralmente acompanhados de atividades físicas perigosas que provocam danos significativos a pessoas e propriedades, gerando um grande número de vítimas ou até mesmo mortes. Uma maneira de mitigar os danos causados por estes desastres é a utilização de Sistemas de Alertas Meteorológicos (SAM); sendo detectado um risco iminente, diferentes tipos de alertas podem ser acionados objetivando a mobilização antecipada das equipes de emergência. O presente trabalho visa contribuir com o Sistema de Proteção da Amazônia (SIPAM) ou com órgãos semelhantes para a resolução do problema de comunicação referente à emissão dos alertas e a mobilização, destinando-se principalmente à ação da Defesa Civil e órgãos competentes junto à população em função dos EME ocorridos. Nesta pesquisa foi realizada uma investigação comparativa com dez trabalhos objetivando conhecer e analisar as principais características de um Sistema de Alerta, as quais foram incorporadas neste projeto, destacando-se o apoio de um Sistema Multiagente para auxiliar o SAM, e o uso das tecnologias de SMS (Short Message Service) e E-mail para o envio do alerta. Testes do sistema evidenciaram que a abordagem adotada mostrou-se promissora, apresentando tempos de envio de alertas menores que os encontrados na literatura e com alta taxa de usuários confirmados, fator de muita importância para a minimização dos efeitos dos EME junto à população atingida.

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