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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.
21

Distribuição espaço-temporal da aids na Bahia, período 2002 a 2012

Sousa, Alba Regina de 02 December 2014 (has links)
Submitted by Maria Creuza Silva (mariakreuza@yahoo.com.br) on 2015-04-06T18:16:54Z No. of bitstreams: 1 Diss MP Alba Regina de Sousa. 2014.pdf: 2449106 bytes, checksum: b39d805e5a2f5c61378cd2fdc55741d7 (MD5) / Approved for entry into archive by Maria Creuza Silva (mariakreuza@yahoo.com.br) on 2015-04-15T14:34:15Z (GMT) No. of bitstreams: 1 Diss MP Alba Regina de Sousa. 2014.pdf: 2449106 bytes, checksum: b39d805e5a2f5c61378cd2fdc55741d7 (MD5) / Made available in DSpace on 2015-04-15T14:34:15Z (GMT). No. of bitstreams: 1 Diss MP Alba Regina de Sousa. 2014.pdf: 2449106 bytes, checksum: b39d805e5a2f5c61378cd2fdc55741d7 (MD5) / A epidemia da aids persiste como grande problema de saúde pública e conhecer sua dinâmica é importante para o planejamento de políticas públicas. Este estudo analisou a evolução espaço-temporal da aids no estado da Bahia, por meio de estudo ecológico de agregados de dados no tempo e no espaço geográfico da Bahia, no período 2002 a 2012. A população do estudo foi composta por pessoas com diagnóstico de aids, residentes no estado. Os dados resultaram do relacionamento das bases do Sistema Nacional de Agravos de Notificação (Sinan), do Sistema de Informação de Mortalidade (SIM), do Sistema de Controle Logístico de Medicamentos (Siclom) e do Sistema de Controle de Exames Laboratoriais (Siscel), realizado pelo Departamento de DST, Aids e Hepatites Virais/Ministério da Saúde, disponibilizados para as secretarias estaduais de saúde. As variáveis estudadas foram: sexo, faixa etária, escolaridade, ano do diagnóstico da aids, categoria de exposição e município de residência. Foram calculadas taxas de incidência e, para estimar a tendência da epidemia no estado, utilizou-se a regressão linear simples das taxas anuais de incidência de aids no período de 2002-2012. Utilizaram-se planilhas do Excel para o cálculo das taxas de incidência e o pacote estatístico STATA v.12 para a regressão linear. De 2002 a 2012 foram registrados 16.406 casos de aids no estado da Bahia, com predominância no sexo masculino com maior proporção de casos 59,5% (9.765) dos casos. A taxa de incidência de aids na Bahia demonstrou tendência de crescimento com estabilização nos últimos 3 anos da série; em 2002 foi 9,2 por 100.000 hab. e 12,9 por 100.000 hab. em 2012. As taxas de incidência indicaram tendência de crescimento da epidemia para ambos os sexos, embora ainda haja maior expressividade para o sexo masculino. A razão média de casos entre homens e mulheres no período foi 1,5:1. A transmissão sexual foi a categoria de exposição mais referida. Em relação ao nível de escolaridade, a maior proporção dos casos referiu ensino fundamental completo e incompleto. Quanto à raça/cor, a maior proporção de casos foi em indivíduos de cor parda. Em relação à faixa etária, não houve crescimento em menores de 5 anos e as maiores taxas de incidências se situaram nas faixas de 30 a 39 , além de ocorrer crescimento nas faixas de 50 e mais. Do ponto de vista regional, observou-se a existência de casos em todas as regiões da Bahia As regiões são semelhantes em relação á características sociodemográficas da aids, entretanto diferem em relação a magnitude da epidemia. Os resultados sugerem que a aids continua crescendo no estado.
22

Análise temporal da mortalidade por causas externas em idosos no estado de Pernambuco, 1981 a 2010

RODRIGUES, Maria Olívia Soares 12 August 2014 (has links)
Submitted by Irene Nascimento (irene.kessia@ufpe.br) on 2016-10-04T19:39:38Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) DissertacaoOlivia.pdf: 1004798 bytes, checksum: f09f8e4112ed9300263af5555bf3202b (MD5) / Made available in DSpace on 2016-10-04T19:39:38Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) DissertacaoOlivia.pdf: 1004798 bytes, checksum: f09f8e4112ed9300263af5555bf3202b (MD5) Previous issue date: 2014-08-12 / CAPES / O objetivo deste estudo foi analisar os aspectos temporais da mortalidade por causas externas em idosos no estado de Pernambuco entre os anos de 1981 a 2010. Trata-se de um estudo ecológico exploratório do tipo série temporal. Os dados de mortalidade foram obtidos do Sistema de Informações sobre Mortalidade e os dados demográficos do Instituto Brasileiro de Geografia e Estatística, disponíveis no Datasus/MS. Foram calculados os coeficientes de mortalidade por causas externas geral, segundo sexo, Gerência Regional de Saúde de residência por 100 mil idosos e os coeficientes de mortalidade por causas externas específicas. Em seguida, foram calculadas as médias, desvios padrão e mediana desses coeficientes no período de estudo. Para a análise de tendência foi utilizada a técnica de alisamento spline. Para análise de sazonalidade, foi calculado o índice de sazonalidade. O Sistema de Informação sobre Mortalidade registrou 763.666 mortes em idosos de 1981 a 2010 das quais 19.132 (2,5%) foram por causas externas, a média do período foi de 101,4 óbitos por 100 mil idosos, com uma razão média de sexos de 2,6 mortes masculinas para cada morte feminina. Os maiores coeficientes de mortalidade por causas externas foram encontrados na I Gerência Regional de Saúde. As quedas apresentaram tendência de crescimento e os suicídios de redução. O estudo sinaliza a provável carência de políticas públicas de prevenção dos acidentes e violências nessa faixa etária. No entanto, destaca a redução dos suicídios como fator positivo na evolução dos óbitos por causas externas nos idosos pernambucanos. / The aim of this study was to analyze the temporal aspects of mortality from external causes in the elderly in Pernambuco between the years 1981-2010. . In order to do this, an Ecological study was done with seasonal and temporal analysis. Data on deaths were removed from the Mortality Information System and Population date from the Brazilian Institute of Geography and Statistics, available on Datasus / MS. Mortality rates for general external causes were calculated according to sex, Regional Health Management of residence for 100,000 elderly and mortality rates for specific external causes. Then we calculated the mean, standard deviation and median of the coefficients in the study period. In the trend analysis, the reason of death was softened by spline. For the seasonal index was calculated and compared. The Mortality Information System recorded 763,666 deaths in the elderly from 1981 to 2010 of which 19,132 (2.5%) were by external causes, the average for the period was 101.4 deaths per 100,000 elderly, with an average sex ratio of 2.6 male deaths for each female death. The highest mortality rates from external causes were found in the Regional Health Management I. Falls presented a growth trend and suicide reduction. The study indicates the probable absence of public policies to prevent accidents and violence in this age group. However, highlights the reduction in suicides as a positive factor in the evolution of deaths from external causes in the elderly Pernambuco.
23

Um estudo sobre a distribuição da raiva no Estado do Paraná de 1981 a 2012 / A study on the rabies distribution on Paraná State from 1981 to 2012

Thaisa Lucas Sandri 17 March 2014 (has links)
A raiva é uma zoonose viral que afeta o Sistema Nervoso Central (SNC) causando encefalite e meningoencefalite, de evolução aguda e fatal, que acomete mamíferos carnívoros e morcegos, e periodicamente se manifesta sob a forma de epizootias ou surtos epidêmicos em populações humanas. Neste estudo foram analisadas 16.190 amostras de bovinos, equídeos e morcegos, e menos frequentemente de outros mamíferos durante o período de 1981 a 2012, provenientes do Estado do Paraná. Desse total, 2.766 amostras foram positivas para raiva; 81,74% foram de bovinos, 10,34% de equídeos, 4,05% de morcegos, 2,31% em animais de produção não bovinos, 1,52% em caninos e 0,04%em outros animais. Ao longo da série histórica, há, para os bovinos, uma tendência de aumento das notificações e não foram observadas variação sazonal e cíclica. Na análise espaço-temporal foi detectado um aglomerado mais provável de notificações de raiva em bovinos, envolvendo 20 municípios da região litorânea e metropolitana de Curitiba entre 1981 e 1987. Além dele, foram detectados seis aglomerados secundários sugerindo uma migração da raiva ao longo do tempo no Estado do Paraná. Ao longo da série histórica dos equídeos há uma tendência de diminuição das notificações e não foram observadas variação sazonal e cíclica. Os clusters encontrados na análise espaço-temporal da raiva nos equídeos corroboram com aqueles encontrados na análise dos bovinos localizados nas mesmas regiões durante no mesmo período, sugerindo a migração do vírus da raiva no mesmo sentido da observada na análise dos bovinos. Durante o período de 1981 a 1997, os casos de raiva em morcegos acompanham o trajeto da migração dos aglomerados dos bovinos e dos equídeos, o que demonstra que a raiva ocorre endemicamente no território do Estado do Paraná em herbívoros e morcegos. / Rabies is a viral zoonosis that affects the central nervous system (CNS) causing encephalitis and meningoencephalitis, acute and fatal outcome, which affects mammalian carnivores and bats, and periodically manifests itself in the form of epidemics or outbreaks in human populations. In this study 16,190 samples of cattle, horses and bats, and less frequently other mammals were analyzed during the period 1981 to 2012, from the State of Paraná. Of this total, 2,766 samples were positive for rabies; 81.74 % were bovine, equine 10.34 %, 4.05 % of bats, 2.31 % in livestock no bovine, 1.52 % in canine, and 0.04% in other animals. Throughout the time series, there is, for cattle, a trend of increased reporting and no seasonal or cyclical variations were observed. In spatio-temporal analysis, more likely to notifications of rabies in cattle, a cluster involving 20 municipalities in coastal and metropolitan Curitiba between 1981 and 1987 was detected. Besides this, six sub clusters were detected suggesting a migration of anger over time in the state of Paraná. Throughout the historical series of equine there is a downward trend in notifications and no seasonal and cyclical variations were observed. Clusters found in the spatio-temporal analysis of rabies in horses corroborate those found in the analysis of cattle located in the same regions during the same period, suggesting the migration of rabies virus in the same direction as that observed in the cattle analysis. During the period from 1981 to 1997, cases of rabies in bats follow the migration path of clusters of bovine and equine. This shows that rabies is endemic in the state of Paraná in herbivores and bats.
24

Análise temporal dos setores de aglomerados subnormais dos censos 2000 e 2010: o estudo de caso da subprefeitura de São Mateus no município de São Paulo-SP / Temporal analysis of subnormal agglomerates enumeration districts of Brazilian census 2000 and 2010: the case study of São Mateus borough in Sao Paulo city

Alexandra Aguiar Pedro 08 April 2016 (has links)
O propósito deste trabalho é investigar as características dos dados sobre aglomerados subnormais, na subprefeitura de São Mateus - município de São Paulo - SP, tendo em vista a realização de análises temporais. Os censos demográficos, por meio dos setores de aglomerados subnormais, são uma importante fonte de dados socioeconômicos e demográficos sobre favelas, coletados periodicamente e disponibilizados pelo IBGE para todos os municípios brasileiros. No entanto, pesquisadores e poder público estão sujeitos às controvérsias metodológicas e questões cartográficas que ainda dificultam o uso dessas informações. No presente estudo, foram identificadas e sistematizadas as características dos aglomerados subnormais. Posteriormente, essas informações foram verificadas quanto à sua ocorrência e significância por meio do estudo de caso, com sobreposição das malhas censitárias dos censos 2000 e 2010, e das bases cadastrais da prefeitura em um sistema de informação geográfica (SIG). Aprimoramentos foram observados nos processos e resultados do censo de 2010, comparado com o censo de 2000. Entretanto, os dados sobre aglomerados subnormais ainda apresentam características que dificultam a realização de análises temporais, destacando-se os seguintes resultados: a) 96,5% dos setores subnormais do estudo de caso, identificados como tal somente em 2010 são constituídos por favelas implantadas até 1999; b) 42,5% dos setores subnormais de 2010 referem-se à novas identificações de favelas em relação a 2000; c) 55% dos setores subnormais identificados em 2010 são resultantes de subdivisão ou agregação dos setores do censo 2000; d) em 26% dos setores subnormais em 2010 há conjuntos habitacionais ou residências não consideradas favelas pela prefeitura; e) três setores subnormais em 2010 não possuem em sua área, favelas cadastradas pela PMSP e quatro favelas cadastradas na PMSP não foram demarcadas como setores subnormais no censo 2010. As contradições nos dados censitários entre 2000 e 2010 e destes em relação às favelas da prefeitura tornam as análises temporais pouco precisas. O fato de que os dados estão agregados em setores que foram muito modificados entre um censo e outro agrava esta situação, na medida em que limita a comparação dos dados entre os períodos. / The purpose of this research is to analyze the data on subnormal agglomerates (special enumeration districts to identify the most common kind of slum in Brazil, the favelas), provided by the Brazilian Statistics Office, through the case study area, São Mateus borough, located in Sao Paulo city, with regard to achieving temporal analysis. The population census, through the subnormal agglomerates enumeration districts, are an important source of socioeconomic and demographic data on favelas, collected periodically and available to all Brazilian municipalities. However, researchers and public authorities have been subject to methodological controversies and cartographic issues that still complicate the use of this information. This research identifies and systematizes the characteristics relating to subnormal agglomerates. In the sequence, this information is verified according to its occurrence and significance through the case study area, by overlaying the vector census zoning 2000-2010 and the cadastral databases from Sao Paulo city hall, in geographic information system (GIS). Improvements in the processes and results of 2010 census were observed, compared to the 2000 census. However, the subnormal agglomerates data still present characteristics that complicates the accomplishment of temporal analysis. The highlighted results are: a) 96.5% of the subnormal enumeration districts in the case study, identified only in 2010 are favelas implemented until 1999; b) 42.5% of subnormal enumeration districts in 2010 were new favelas identifications; c) 55% of subnormal enumeration districts identified in 2010 are the result of subdivision or aggregation of the 2000 census enumeration districts; d) in 26% of subnormal enumeration districts in 2010 there are social housing buildings or houses not considered favelas by the municipal cadastre; e) three subnormal enumeration districts in 2010 have no correspondence with favelas registered by the municipality and four favelas registered by the municipality were not delineated as subnormal agglomerates in the 2010 census. The contradictions in census data between 2000 and 2010, and the differences found in comparison to the favela municipal database become the temporal analysis less accurate. This imprecision tends to expand due the deep modifications on the enumeration districts, which limit the data comparison.
25

Utvärdering av temporala analysmetoder inom brottskategorin bostadsinbrott

Svenhag, Olle January 2015 (has links)
Context. In year 2013 the number of reported residential burglariesin Sweden was 21000, where only 4-5 percent of those actuallygot solved [1]. The Swedish police is trying to improve their way ofworking to increase the number of solved burglaries, this by structuringthe data collection and analysing with computer science methods.Temporal analysis is the key to gure out when crime actually takesplace. Objectives. This thesis study ve dierent methods for analysingthe temporal data of residential burglaries. The temporal analysis isperformed on three time spans: time of day, day of the week and dayof the month. The objective is to evaluate the ve methods in thethree time spans and decide which method is the most suitable foreach of them. Methods. This study includes three experiments testing all ve methodson the three time spans. The experiments focus on comparing theobserved data against the data of burglaries with a known specictime of the crime. In order to test the performance of each method aChi-squared goodness-of-t test was used, as well as a visual comparisonof the produced plots. Results. The results showed that the Aoristic-method was the mostsuitable method to use when analysing temporal data of residentialburglars, if looking at the time of day, day of the week and day ofthe month. Using the methods we also generated plots of the threetemporal distributions, with an R script. Conclusions. We concluded that using the Aoristic-method is themost suitable method to use to generate plots from the temporal data.We also concluded that using this script with the Aoristic-method togenerate plots, would make it possible for the police to resource allocationaccording to when burglaries actually take place.
26

Análise dos casos de hanseníase na região metropolitana de Aracaju no período de 2001 a 2013 utilizando os dados do SINAN, Sergipe, Brasil / Analysis of leprosy cases in Aracaju of metropolitan region in the period 2001 to 2013 using the sinan data, Sergipe, Brazil

Menezes, Jurema Cristina Machado de 28 May 2015 (has links)
Leprosy is a chronic infectious disease caused by the bacillus Mycobacterium leprae, which is transmitted from person to person by continuous contact with infectious patients without treatment. In Brazil, due to its endemicity is an important public health problem. This study aimed to analyze and map epidemiological data of leprosy in the metropolitan area of Aracaju, Sergipe. It performed a longitudinal retrospective study based on secondary data from the Notifiable Diseases Information System (SINAN) aiming to achieve the spatial distribution, temporal analysis and describe the epidemiological profile of leprosy in the metropolitan area of Aracaju, Sergipe, Brazil, in the period from 2001 to 2013. Information regarding the patients were collected in the SINAN database provided by the State Health Department of Sergipe. Interest surveyed variables were: municipality of residence, number of cases diagnosed per year, age, education, race, operational classification, clinical form, disability grade, form of entry into the reporting system. The temporal analysis of leprosy in the metropolitan area of Aracaju identified a declining trend in the disease, when studying the municipalities together. The high number of cases with indeterminate clinical form shows that there is a high bacterial load circulating in the community, the statement of Kernel density showed that the hottest areas are concentrated in the center of Aracaju, and will spread by other municipalities in Region Metropolitan Aracaju. These results show the regions where the risk of infection by the bacillus Mycobacterium leprae can occur, showing that leprosy transmission is occurring in the study area, generating new cases. It is of utmost importance that the research activities and leprosy control are maintained and developed for the purpose of disposal and effective control of this disease. / A hanseníase é uma doença infectocontagiosa crônica, causada pelo bacilo Mycobacterium leprae, que é transmitido de pessoa a pessoa pelo contato contínuo com doentes contagiantes sem tratamento. No Brasil, devido a sua endemicidade constitui em um importante problema de saúde pública. Este estudo teve como objetivo principal analisar e mapear dados epidemiológicos da hanseníase na Região Metropolitana de Aracaju, Sergipe. Foi realizado um estudo retrospectivo longitudinal baseado em dados secundários do Sistema de Informação de Agravos Notificáveis (SINAN) com os objetivos de realizar a distribuição espacial, análise temporal e descrever o perfil epidemiológico da hanseníase na Região Metropolitana de Aracaju, Sergipe, Brasil, no período de 2001 a 2013. As informações referentes aos pacientes foram coletadas no banco de dados do SINAN disponibilizadas pela Secretaria Estadual de Saúde de Sergipe. As variáveis de interesse pesquisadas foram: município de residência, número de casos diagnosticados por ano, idade, escolaridade, raça, classificação operacional, forma clínica, grau de incapacidade, forma de ingresso no sistema de notificação. A análise temporal da hanseníase na Região Metropolitana de Aracaju identificou uma tendência ao declínio da doença, quando se estuda os municípios em conjunto. O elevado número de casos com a forma clínica indeterminada demonstra que há uma alta carga bacilar circulando na comunidade, O mapa da densidade de Kernel demonstrou que as áreas mais quentes estão concentradas no centro de Aracaju, e que vai se difundindo pelos outros municípios da Região Metropolitana de Aracaju. Esses resultados evidenciam as regiões onde o risco de infecção pelo bacilo Mycobacterium leprae pode ocorrer, demonstrando que a transmissão da hanseníase está ocorrendo na área em estudo, gerando novos casos. É de extrema importância que as atividades de pesquisa e controle da hanseníase sejam mantidas e desenvolvidas, com o propósito de eliminação e um controle efetivo dessa doença.
27

A Framework for Simulating and Analyzing Multi-UAV Persistent Search and Retrieval with Stochastic Target Appearance

Day, Ryan David 07 August 2020 (has links)
In recent years, advances in small unmanned aerial vehicle (UAV) technology have transformed the use cases of these aircraft from hobby flying to industrial and business applications. These maneuverable, easily deployed tools can be retrofitted with a myriad of sensors and equipment, which make them suitable to perform a variety of specialized tasks. With increasing UAV capabilities, the function of small UAVs can be extended from pure monitoring or surveillance to the dual objective of monitoring an environment for events and addressing the events in some way. This thesis seeks to explore a subdomain of the dual objective problem described, referred to in this thesis as the multi-UAV persistent search and retrieval task with stochastic target appearance (PSR-STA), in which UAVs continuously search an area over a long period of time for targets of interest, which appear according to a probabilistic model, to retrieve and deliver them to a collector location. The advent of high-speed computers and agent-based modeling theory enable the simulation of multi-UAV PSR-STA. However, it can be complicated to combine parts of multi-UAV PSR-STA such as motion models and multi-UAV coordination into one integrated system, and even after they are combined successfully, it is difficult to analyze the system except with simple comparison tools. This thesis 1) proposes a framework that builds a foundation for understanding how to simulate and analyze multi-UAV PSR-STA through prescribing important design decisions and methods for simulation and 2) identifies metrics, analysis tools, and trends related to overall system effectiveness for multi-UAV PSR-STA. A case study of multi-UAV park cleanup is implemented where many simulations with input parameters chosen by a latin hypercube design of experiments are examined, algorithms for choosing the locations of collectors and charging stations based on probabilistic information are proposed, and the differences in effectiveness between four coverage search patterns are analyzed. Measures are highlighted that provide insight into performance variability over time and space. Line charts and the discrete Fourier transform are used to understand temporal patterns inherent in the data. Principal component analysis is used to analyze relevant spatial patterns in effectiveness, and a random forest surrogate model with a profiler is used to explore the non-linear influence of input parameters on the spatial patterns. The trellis chart or figure of figures method is presented for visualizing spatial and temporal data across many simulations. A second set of experiments based on the park cleanup case study are performed and examined to verify the benefits of these methods.
28

Analyse de l'activité d'éclairs des systèmes orageux dans le bassin du Congo / Analysis of the lightning activity of thunderstorms systemes in the Congo basin

Kigotsi Kasereka, Jean 11 May 2018 (has links)
Cette thèse est consacrée à une analyse de l'activité d'éclairs des systèmes orageux en Afrique équatoriale (10°E - 35°E ; 15°S - 10°N) sur la période de temps 2005-2013. Tout d'abord, les données fournies par le réseau global de détection d'éclairs WWLLN (World Wide Lightning Location Network) ont été comparées à celles obtenues par le capteur optique spatial LIS (Lightning Imaging Sensor) afin d'estimer l'efficacité de détection relative du WWLLN. Ensuite, elles ont permis d'établir une climatologie régionale à haute résolution de l'activité d'éclairs. Enfin, elles ont été associées à des données sur les caractéristiques nuageuses et météorologiques pour des études de cas d'orages dans différentes situations, afin d'examiner les corrélations entre activité d'éclairs, activité orageuse, caractéristiques nuageuses et conditions météorologiques. La méthode adaptée pour estimer l'efficacité de détection du WWLLN dans la zone d'étude a permis d'obtenir des valeurs compatibles avec celles trouvées dans d'autres régions du monde, et de mettre en évidence une variabilité spatio-temporelle qui aide à l'interprétation des changements affectant plusieurs paramètres de l'activité d'éclairs. La climatologie réalisée dévoile des caractéristiques originales de l'évolution temporelle et de la distribution spatiale de l'activité d'éclairs, notamment celles d'un maximum très aigu dans l'Est de la République Démocratique du Congo. Ainsi, la localisation, les dimensions, la forme, la persistance saisonnière et l'environnement de ce maximum ont été précisés. La distribution zonale des éclairs montre une forte proportion dans la bande tropicale sud, liée au maximum principal mais aussi à une forte activité étalée longitudinalement et constituant un large maximum secondaire où l'activité orageuse est plus variable spatialement d'une année à l'autre, temporellement d'une saison à l'autre, et où le cycle diurne est moins marqué.[...] / This thesis is devoted to an analysis of the lightning activity of storm systems in Equatorial Africa (10°E-35°E; 15°S-10°N) over the period 2005-2013. Firstly, data from the World Wide Lightning Location Network (WWLLN) were compared with those from the Lightning Imaging Sensor (LIS) to estimate the relative detection efficiency of the WWLLN. Then, they established a high-resolution regional climatology of lightning activity. Finally, they were combined with data on cloud and meteorological characteristics to carry out thunderstorm case studies in different situations in order to examine the correlations between lightning activity, storm activity, cloud characteristics and meteorological conditions. The appropriate method introduced for estimating the WWLLN detection efficiency in the study area provides values ??consistent with those found in other regions of the world. Its spatial and temporal variability helps to interpret changes affecting several parameters of lightning activity. The climatology realized reveals original characteristics of the temporal evolution and the spatial distribution of the lightning activity, in particular those of a very sharp maximum in the Eastern Democratic Republic of Congo. Thus, the location, the dimensions, the shape, the seasonal persistence and the environment of this maximum have been specified. The zonal distribution of lightning shows a high proportion in the southern tropical band, linked to the principal maximum but also to a high activity spread out longitudinally and constituting a large secondary maximum where the storm activity is more spatially variable from one year to another, temporally from one season to another, and where the diurnal cycle is less marked. [...]
29

Geodetic methods of mapping earthquake-induced ground deformation and building damage

Diederichs, Anna K. 25 August 2020 (has links)
I use temporal lidar and radar to reveal fault rupture kinematics and to test a method of mapping earthquake-induced structural damage. Using pre- and post-event data, these applications of remote technology offer unique perspectives of earthquake effects. Lidar point clouds can produce high resolution, three-dimensional terrain maps, so subtle landscape shifts can be discerned through temporal analysis, providing detailed imagery of co-seismic ground displacement and faulting. All-weather radar systems record back-scattered signal amplitude and phase. Pre- and post-event comparisons of phase can illuminate co-seismic structural damage using an oblique look angle, most sensitive to changes in building heights. Extracted information from these geodetic methods may be used to inform decisions on future earthquake modeling and emergency response. In the first major section of this thesis, I calculate co-seismic 3D ground deformation produced by the Papatea fault using differential lidar. I demonstrate that this fault - a key element within the 2016 Mw 7.8 Kaikoura earthquake - has a distinctly non-planar geometry, far exceeded typical co-seismic slip-to-length ratios, and defied Andersonian mechanics by slipping vertically at steep angles. Its surface deformation is poorly reproduced by elastic dislocation models, suggesting the Papatea fault did not release stored strain energy as typically assumed, perhaps explaining its seismic quiescence in back-projections. Instead, it slipped in response to neighboring fault movements, creating a localized space problem, accounting for its anelastic deformation field. Thus, modeling complex, multiple-fault earthquakes as slip on planar faults embedded in an elastic medium may not always be appropriate. For the second major part of this thesis, I compare mean values of interferometric synthetic aperture radar (InSAR) coherence change across four case studies of earthquake-induced building damage. These include the 2016 Amatrice earthquake, the 2017 Puebla-Morelos earthquake, the 2017 Sarpol-e-Zahab earthquake, and the 2018 Anchorage earthquake. I examine the influences of environmental and urban characteristics on co-seismic coherence change using Sentinel-1 imagery and compare the outcomes of various damage levels. I do not find consistent values of mean coherence change to distinguish levels of damage across the case studies, indicating coherence change values vary with location, environment, and damage pattern. However, this method of damage mapping shows potential as a useful tool in earthquake emergency response, capable of quickly identifying localized areas of high damage in areas with low snow and vegetation cover. Given the large spatial coverage and relatively quick, low-cost acquisition of SAR imagery, this method could provide damage estimates for unsafe or remote regions or for areas unable to self-report damage. / Graduate
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A Spatio-Temporal Analysis of Landscape Change within the Eastern Terai, India : Linking Grassland and Forest Loss to Change in River Course and Land Use

Biswas, Tanushree 01 May 2010 (has links)
Land degradation is one of the most important drivers of landscape change around the globe. This dissertation examines land use-land cover change within a mosaic landscape in Eastern Terai, India, and shows evidence of anthropogenic factors contributing to landscape change. Land use and land cover change were examined within the Alipurduar Subdivision, a representative of the Eastern Terai landscape and the Jaldapara Wildlife Sanctuary, a protected area nested within Alipurduar through the use of multi-temporal satellite data over the past 28 years (1978 – 2006). This study establishes the potential of remote sensing technology to identify the drivers of landscape change; it provides an assessment of how regional drivers of landscape change influence the change within smaller local study extents and provides a methodology to map different types of grassland and monitor their loss within the region. The Normalized Difference Vegetation Index (NDVI) and a Normalized Difference Dry Index (NDDI) were found instrumental in change detection and the classification of different grasslands found inside the park based on their location, structure, and composition. Successful spectral segregation of different types of grasslands and their direct association with different grassland specialist species (e.g., hispid hare, hog deer, Bengal florican) clearly showed the potential of remote sensing technology to efficiently monitor these grasslands and assist in species conservation. Temporal analysis provided evidence of the loss of dense forest and grasslands within both study areas with a considerably higher rate of loss outside the protected area than inside. Results show a decline of forest from 40% in 1978 to 25% in 2006 across Alipurduar. Future trends project forest cover and grassland within Alipurduar to reduce to 15% and 5%, respectively. Within the Alipurduar, deforestation due to growth of tea industry was the primary driver of change. Flooding changed the landscape, but more intensely inside the wildlife preserve. Change of the river course inside Jaldapara during the flood of 1968 significantly altered the distribution of grassland inside the park. Unless, the direction of landscape change is altered, future trends predict growth of the tea industry within the region, increased forest loss, and homogenization of the landscape.

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