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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

Conflitos pela terra na Gleba Ponte Queimada: experiências de disputas por terras em narrativas (1960-1972) / Conflict in the land Bridge Burned Gleba: dispute experiences lands in narratives (1960-1972)

Silva, Tatiane Karine Matos da 28 April 2016 (has links)
Made available in DSpace on 2017-07-10T17:55:40Z (GMT). No. of bitstreams: 1 2016Tatiane_Karine_Silva.pdf: 2086089 bytes, checksum: a945c06eb113b9f2bf4287815fe59a83 (MD5) Previous issue date: 2016-04-28 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / This paper discusses the dynamics of conflicts over land in a border region from the squatter experiences in disputes over land in Gleba Bridge Burned, in the municipality of Santa Helena, Paraná, between 1960 and 1972. We seek to analyze the practices through several narratives that permeated clashes between squatters and landowners in two spaces of said Gleba, one in Finance Rimacla and the other in Corner Blue Sky community. From this perspective, we are interested in realizing the possibilities and positions built by squatters who had to deal with these conflicting processes, which resulted in his expulsion from places where hitherto lived. We emphasize, therefore, the pressures that permeated their lives, violence and insecurity, as well as prepare their stories about those disputes / Este trabalho problematiza as dinâmicas de conflitos por terras em uma região de fronteira a partir das experiências de posseiros em disputa pela terra na Gleba Ponte Queimada, localizada no município de Santa Helena, Paraná, entre 1960 e 1972. Buscamos analisar as práticas, por meio de narrativas diversas, que permearam embates entre posseiros e proprietários de terras em dois espaços da referida Gleba, um na Fazenda Rimacla e o outro na comunidade de Esquina Céu Azul. Nessa perspectiva, interessa-nos perceber as possibilidades e posicionamentos construídos pelos posseiros que tiveram que lidar com estes processos conflituosos, os quais resultaram em sua expulsão dos lugares em que até então viviam. Enfatizamos, assim, as pressões que permeavam suas vidas, a violência e a insegurança, bem como elaboram suas narrativas acerca daquelas disputas
22

Influência da balneoterapia na descolonização de Staphylococcus aureus e Pseudomonas aeruginosa em pacientes queimados internados em um hospital público localizado na cidade do Rio de Janeiro

Deutsch, Gabriela 24 March 2017 (has links)
Submitted by Biblioteca da Faculdade de Farmácia (bff@ndc.uff.br) on 2017-03-24T17:22:23Z No. of bitstreams: 1 Deutsch, Gabriela [Dissertação, 2014].pdf: 1124546 bytes, checksum: 4c2efe5d127b5965bea25e458da2afc4 (MD5) / Made available in DSpace on 2017-03-24T17:22:23Z (GMT). No. of bitstreams: 1 Deutsch, Gabriela [Dissertação, 2014].pdf: 1124546 bytes, checksum: 4c2efe5d127b5965bea25e458da2afc4 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A balneoterapia é um importante procedimento realizado diariamente em pacientes queimados. Esta prática consiste na limpeza mecânica com fricção manual sobre as áreas lesionadas pela queimadura utilizando antisséptico. Poucas são as evidências de que sua prática seja efetiva na higienização das feridas e na prevenção de infecção cruzada entre pacientes que utilizam o mesmo tanque. Neste projeto, buscou-se estudar a influência da balneoterapia na descolonização da superfície corporal queimada (SCQ) de pacientes internados em um centro de tratamento de queimaduras (CTQ), quanto à presença de cepas de Staphylococcus aureus e Pseudomonas aeruginosa. Swabs foram coletados durante a realização da balneoterapia de 18 pacientes por 14 semanas. A água utilizada também foi avaliada. Testes fenotípicos e genotípicos foram utilizados para identificação de S. aureus e P. aeruginosa. A susceptibilidade a antimicrobianos e biocidas foi verificada segundo os critérios do Clinical and Laboratory Standards Institute (CLSI). Pulsed-field gel electrophoresis (PFGE) foi utilizado para avaliar a diversidade genômica. Análise exploratória das variáveis envolvidas no processo da balneoterapia foi determinado pela estatística descritiva e testes estatísticos não paramétricos foram utilizados na análise dos fatores de risco. Trezentos e cinquenta e dois swabs foram coletados dos quais 214 (61%) da SCQ, 60 (17%) da cavidade nasal e 78 (22%) da mesa onde ocorreu a balneoterapia. Detectou-se 13 cepas de S. aureus e 39 de P. aeruginosa. A concentração mínima inibitória (CMI) para sulfadiazina de prata foi ≥32μg/mL para as cepas de S. aureus enquanto que para a P. aeruginosa a maioria das cepas apresentou CMI de 128μg/mL. Com relação a clorexidina, as cepas de S.aureus apresentaram um CMI variando de 2 a 8g/mL enquanto para P. aeruginosa a variação foi de 16 a 64μg/mL. Cinco amostras foram identificadas como S. aureus resistentes a meticilina (MRSA) e nove como P. aeruginosa resistentes a carbapenêmicos. A análise do perfil de fragmentação do DNA total (PFGE) nas cepas de P. aeruginosa demonstrou a existência de 10 clones entre 35 cepas analisadas. O tipo A foi o mais prevalente, com 23 cepas distribuídas em 8 subtipos. Estes estavam presentes na SCQ coletada antes e após o banho e nas superfícies da mesa de banho, sugerindo que há contaminação cruzada de um indivíduo para o outro, de uma área queimada para outra no mesmo indivíduo, da mesa da balneoterapia para indivíduos e finalmente do indivíduo para mesa. Os resultados não se mostraram estatisticamente significativos, no entanto, quatro pacientes que não apresentaram contaminação antes do banho se tornaram positivos após este procedimento, e 10 pacientes que apresentaram contaminação antes do banho, assim permaneceram. Conclui-se que o procedimento de descontaminação não está sendo eficaz uma vez que houve similaridade clonal entre as cepas de P. aeruginosa coletadas em vários pontos e momentos / Balneotherapy is an important procedure usually performed in burn patients. This practice consists on a mechanical cleaning with manual friction on the damaged areas using an antiseptic. There is little evidence that this practice is effective to clean the wounds and avoid cross infection between patients using the same table. In this project, we study the influence of hydrotherapy in the decolonization of burned body surface area (BSA) of patients admitted to a burn center (BC) for the presence of Staphylococcus aureus and Pseudomonas aeruginosa isolates. Thus, swabs were used to collect bacteria from 18 patients submitted to balneotherapy during 14 weeks. The material from bath table and the water used were also evaluated. Genotypic and phenotypic tests were used to identify S. aureus and P. aeruginosa. Susceptibility to antimicrobials and biocides has been verified according to the criteria of the Clinical and Laboratory Standards Institute (CLSI). Genomic diversity was assessed by pulsed-field gel electrophoresis (PFGE). Descriptive statistics were used in the exploratory analysis of the variables involved in the balneotherapy and non-parametric statistical tests were used in process analysis of risk factors. Three hundred fifty-two swabs were collected of which 214 (61%) were from BSA, 60 (17%) from nasal cavity and 78 (22%) from table where balneotherapy occurred. Thirteen isolates were identified as S. aureus and 39 as P. aeruginosa. Minimum inhibitory concentration (MIC) for silver sulfadiazine was ≥ 32μg/mL for S. aureus isolates and 128μg/mL for P. aeruginosa. It is possible that the increased MIC to silver sulfadiazine has occurred by the constant use of this antimicrobial in balneotherapy. However, MIC to chlorhexidine for S. aureus isolates range from 2 to 8mg/mL and for P. aeruginosa range from 16 to 64μg/mL. Furthermore, five S. aureus isolates were identified as methicillin-resistant Staphylococcus aureus (MRSA) and nine as P. aeruginosa resistant to carbapenems. A profile analysis of total P. aeruginosa DNA fragmentation showed 10 clones among 35 strains analyzed. Type A was the most prevalent, with 23 isolates distributed into eight subtypes. These subtypes were present in BSA collected before and after the bath and on the surfaces of the bath table, suggesting that there is cross-contamination from one individual to another, from a burned area to another in the same individual, from the balneotherapy table to an individual and finally from the individual to the table. The results were not statistically significant, however, four patients who were not contaminated before bathing became positive after this procedure, and 10 patients who were contaminated before bathing, remained so. Thus, it is possible to conclude that the procedure is not efficient for the decontamination because there was similarity between the clonal isolates of P. aeruginosa collected at various points and times
23

震災時学区避難者数及び救難物資の推定に関する研究

邵, 俊豪 23 January 2012 (has links)
Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(工学) / 甲第16506号 / 工博第3499号 / 新制||工||1529(附属図書館) / 29163 / 京都大学大学院工学研究科都市環境工学専攻 / (主査)教授 田中 哮義, 教授 田中 仁史, 教授 神吉 紀世子 / 学位規則第4条第1項該当
24

Skeletal changes after post-mortem exposure to fire as an indicator of decomposition stage

Keough, Natalie January 2013 (has links)
Forensic anthropologists and taphonomists are often tasked with interpreting the sequence of events from death through decomposition to skeletonisation. Discovery of burnt bone often evokes questions as to the condition of the body prior to the burn event. The purpose of this study was to evaluate features of thermal damage on bones in relationship to the condition of the bone (dry/wet) and progression of decomposition. Twenty-five pigs in various stages of decomposition (fresh, early, advanced, early & late skeletonisation) were exposed to fire for 30 minutes. The skeletal elements were scored and features included: colour change (unaltered, charred, calcined), brown and heat borders, heat lines, delineation, greasy bone, joint shielding, predictable and minimal cracking, delamination and heatinduced fractures. Colour changes were scored according to a ranked percentage scale (0 – 3) and the remaining traits as absent or present (0/1). Cohen’s Kappa statistics evaluated intraand interobserver error. Density plots and frequency distributions were constructed and multiple regression (categorical variables) and transition analysis were employed. The majority (8) of the 13 traits displayed potential to predict decomposition stage from burned remains. An increase in calcined and charred bone occurred synchronously with an advancement in decomposition. The organic composition of bone and presence of flesh affect the characteristics features of burned bone. Greasy bone occurred most often in the early/fresh stages (fleshed bone). Heat borders, heat lines, delineation, joint shielding, predictable and minimal cracking were associated with wet tissue/bone; whereas brown burn/borders, delamination and other heat-induced fractures were associated with early and late skeletonisation. No statistically significant differences were noted among observers for the majority of the traits except for predictable and minimal cracking and heat-induced fractures in the cranium. Heat-induced changes may assist in estimating decomposition stage from unknown, burnt remains and thereby aid in a providing an indication as to the condition of the bone prior to the burn event. / Thesis (PhD)--University of Pretoria, 2013. / gm2014 / Anatomy / unrestricted
25

Eliminace vad při výrobě ozubených kol / Elimination of defects in the gears manufacturing

Petříček, Vít January 2021 (has links)
The aim of the diploma thesis was to analyze qualitative outages in the production of gears for a gear pump and to minimize them. The largest amount of outages was caused by the burning of the surface during face grinding. After analyzing the current state of production there were created some suggestions to avoid this issue. Also there was found some space to speed up the whole process. Suggestions to eliminate burning have been tested with minimal impact on production. The reduction of outages for burned surface was achieved and also the cycle time was shortened. Those suggestions will be implemented in serial production.
26

Resurrecting Stones Transforming Lives

Elliott, Magdalena Anna 16 May 2013 (has links)
My Polish background and upbringing have had a profound influence on the way I look at architecture. Growing up I was always fascinated by the interplay of new things that were around me, dancing with the old objects and way of life that were still present. How can these two worlds co-exist? Does the rise of one signify the death of the other? My thesis project explores this dichotomy of old and new and how they interact with each other. The site is near Dupont Circle in Northwest Washington DC. I thought it beautifully poetic the idea of a homeless shelter rising above the ruins of a burned out church. A place for spiritual salvation would now morph into a haven for corporeal redemption. The transformation the space demanded was basically cosmetic; it would remain a place for human beings to rediscover themselves. The lingering eminence of the space made me fall in love with it, and the possibility of what it could become, of what it could turn into, drove my desire. / Master of Architecture
27

Miško entomokompleksų kaita pušynų degavietės miško paklotėje / The fluctuation of forest entomocomplex in a pines stand burned area litter

Rekašius, Stasys 16 June 2006 (has links)
Study object. The research was made in two forest stands: one was affected by fire and another without fire damage. A sample plot was in a pine stand damaged by fire a year ago, which is is in Kaunas forest enterprise, in Kulautuva forest department. The stand is in square No. 169 and the plots numbers are 14 and 15. The damaged area takes 0,4 hectare. It is 100% pine stand with a site index Nbl. Study aim. To investigate the low fire influence on pine stand litter entomocomplex fluctuation: on their number and seasonal dynamic, on their distrubution by trophical groups, on species abundance and variety in a fire damaged stands. Methods. The research was made in 2004 since april till october. The Barberis ground trap was used in a research. The trap is made from a 150 ml volume and 6,5 cm diameter plastic cruet. The traps were digged into ground to the top of the trap. 1/3 of the trap was filled with a 10% formalin soak. In that case the insects were saved of decomposing and birds. The traps were placed in three zones: in burned area, chequerwise in the place between damaged and undamaged area, and in undamaged area. There were 6 satelites in each area holding 4 traps in each. All together it was 72 traps placed. The distance between the areas was 20 m and the distance between satelites – 10 m. The collected insects were dried and recognized in the labs of Lithuanian University of Agriculture and Forest Research Institute. Results. The total amount of collected insects in 6... [to full text]
28

Atributos químicos e físicos de solo sob mata do Jardim Botânico em Goiânia / Chemical and physical properties of soil under forest of the Botanical Garden in Goiânia

Mesquita, Glaucia Machado 12 December 2014 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2015-05-05T11:16:36Z No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Tese - Glaucia Machado Mesquita - 2014.pdf: 1462595 bytes, checksum: 8236e4606455874ac35952384edc7e41 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2015-05-05T11:20:54Z (GMT) No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Tese - Glaucia Machado Mesquita - 2014.pdf: 1462595 bytes, checksum: 8236e4606455874ac35952384edc7e41 (MD5) / Made available in DSpace on 2015-05-05T11:20:54Z (GMT). No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Tese - Glaucia Machado Mesquita - 2014.pdf: 1462595 bytes, checksum: 8236e4606455874ac35952384edc7e41 (MD5) Previous issue date: 2014-12-12 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In the state of Goiás, its 34 million hectares, only 0.93% represent the Conservation Unit (UCs) full and 2.59% UCs of sustainable use, among these protected areas are the parks. Law Nº. 9985 of July 18, 2000, establishing the National System of Nature Conservation Units (SNUC) is made up of all federal conservation units, state and municipal. This Act establishes criteria and standards for the creation, implementation and management of protected areas. The protected area is the territorial space and its environmental resources, including jurisdictional waters, with relevant natural characteristics, legally instituted by the Government, with conservation objectives and defined limits, under special administration regime, to which adequate safeguards apply to protection. This study aims to evaluate the effect of fire on the chemical and physical properties of soil in a protected area in an urban area, which has preserved area and kills suffered burning process. The study was conducted in the Botanical Garden Amalia Hermano Teixeira (JATH) located in the southern region of Goiânia, Goiás, has a total area of 1,000,000 m2. The soil was classified as Oxisol. In JATH were selected two areas for the study: Burnt Forest (MQ), the area which suffered from illegal burning process in 2010; Preserved forest (MP). Its vegetation is characterized as primary forests have changed, the type Forest Semideciduous. Soil sampling was done at two different times: MQ in September 2012 and MP in May 2013. native forest areas are used as reference areas for soil studies. Thus were estimated physical and chemical indicators of soil penetrometer with up to 40 cm and samples of disturbed and undisturbed soil for the purpose of physical and chemical analysis. Soil samples were collected at depths of 0-5, 5- 10, 10-20 and 20-40 cm. In each area were soil samples collected form a sample grid consists of six rows and five columns with a distance of 10 m between sample points, forming a gride 300 m2. Data were subjected to analysis of variance (ANOVA) and the means were compared within each depth and in each area by 5% Tukey test. The results showed that after four years of the forest burning, observed a concentration of nutrients in the soil profile of MQ in relation to MP at a depth of 0-5 cm. The levels of potassium, calcium and magnesium, present in higher mean values MQ relative to MP, which can be attributed in part to the effect of residual ash. The time after firing do not influence so means the physical soil. / No estado de Goiás, dos seus 34 milhões de hectares, apenas 0,93% representam as Unidades de Conservação (UCs) integral e 2,59% UCs de uso sustentável, dentre estas UCs estão os parques. A Lei nº 9.985, de 18 de julho de 2000, institui o Sistema Nacional de Unidades de Conservação da Natureza (SNUC) constitui-se do conjunto das unidades de conservação federais, estaduais e municipais. Esta Lei estabelece critérios e normas para a criação, implantação e gestão das unidades de conservação. A unidade de conservação é o espaço territorial e seus recursos ambientais, incluindo as águas jurisdicionais, com características naturais relevantes, legalmente instituída pelo poder público, com objetivos de conservação e limites definidos, sob regime especial de administração, ao qual se aplicam garantias adequadas de proteção. O presente trabalho tem como objetivo avaliar o efeito do fogo sobre os atributos químicos e físicos do solo de uma Unidade de Conservação em área urbana, a qual possui área de mata preservada e mata que sofreu processo de queima. O estudo foi realizado no Jardim Botânico Amália Hermano Teixeira (JATH) situado na região sul de Goiânia-Goiás, que possui uma área de aproximadamente 1.000.000 m2. O solo foi classificado como Latossolo Vermelho distrófico. No JATH, foram selecionadas duas áreas distintas para a realização do estudo: Mata queimada (MQ), área a qual sofreu processo de queimada clandestina em 2010; Mata preservada (MP). Sua cobertura vegetal caracteriza-se por ser mata primária já alterada, do tipo Floresta Estacional Semidecidual. A amostragem do solo foi feita em duas épocas distintas: MQ em Setembro de 2012 e MP em Maio de 2013. Áreas de mata nativa são utilizadas como áreas de referencia para estudos do solo. Desta forma foram estimados os indicadores físicos e químicos do solo, com penetrometria até 40 cm e amostras de solo deformadas e indeformadas, para fins de análises físicas e químicas. As amostras de solo foram coletadas nas profundidades de 0-5, 5-10, 10-20 e 20-40 cm. Em cada área foram coletadas amostras de solo formando uma malha amostral composta por seis linhas e cinco colunas com distancia de 10 m entre os pontos amostrais, formando um gride de 300 m2. Os dados obtidos foram submetidos a análises de variância (ANOVA), sendo as médias comparadas dentro de cada profundidade e em cada área pelo teste Tukey a 5%. Os resultados apontaram que após quatro anos da queima da mata, verificando-se uma concentração de nutrientes no perfil do solo da MQ em relação à MP na profundidade de 0- 5 cm. Os teores de potássio, cálcio e magnésio, apresentam valores médios maiores na MQ, em relação à MP, o que pode ser atribuído, em parte, ao efeito residual das cinzas. O tempo decorrido após a queima não influenciou de forma significativa a física do solo.
29

Avaliação da área queimadas no bioma cerrado: proposições para o monitoramento e conversação / Burned areas of assessment in cerrado biome: proposals for monitoring and conservation

Araújo, Fernando Moreira de 03 March 2015 (has links)
Submitted by Cláudia Bueno (claudiamoura18@gmail.com) on 2015-12-04T17:06:29Z No. of bitstreams: 2 Tese - Fernando Moreira de Araújo - 2015.pdf: 6967405 bytes, checksum: 6a3a47f12667e66913e2ad2c041d7e21 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2015-12-07T11:21:38Z (GMT) No. of bitstreams: 2 Tese - Fernando Moreira de Araújo - 2015.pdf: 6967405 bytes, checksum: 6a3a47f12667e66913e2ad2c041d7e21 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2015-12-07T11:21:38Z (GMT). No. of bitstreams: 2 Tese - Fernando Moreira de Araújo - 2015.pdf: 6967405 bytes, checksum: 6a3a47f12667e66913e2ad2c041d7e21 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2015-03-03 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Fire is an important ecological and environmental disturbance phenomenon in the Cerrado biome, which is influenced by climatic, ecological, cultural and economic factors. Burning biomass promotes change in the structure and composition of the soil, accelerates the erosion and sedimentation processes, promotes seed germination, renewal of grasses and releases large amounts of trace gases and aerosols into the atmosphere. This research seeks to understand the location patterns and the recurrence of burned areas to the Cerrado biome according to their different geographical regions from the land cover and land use class, and climatic variables. In particular, we evaluated quantitatively the performance of the MODIS MCD45A1 product for the Cerrado biome, in accordance with the different land use and land cover classes depending on the landscape, using as reference 130 randomly selected burned area polygons, and four randomly selected medium resolution orbital images, both from the month of September. In addition, we analyzed the burned areas spatial and temporal patterns in Brazil, considering both the territorial limits of the six biomes (i.e. Amazônia, Caatinga, Cerado, Mata Atlântica, Pampa and Pantanal) and their main land cover and land use classes (PROBIO MMA). At last, for burned areas greater than 2 km², we evaluated their patterns (spatial and temporal) and frequency of recurrence (burned areas that intersect more than 50%), as well as their interanual and seasonal climatic variations from vegetation index (EVI), precipitation (TRMM) and evapotranspiration (MOD16) images. These images were analyzed in association with the four groups of recurrence (burned areas with recurrence every four years) to determine the different burning regimes and the pre and post burning vegetation responses. The MCD45A1 polygons (September) had good relationship with the reference mapping (Landsat base) (r² = 0.92) and also with the hotspots (MOD14 and MYD14 - monthly data) (r² = 0.89). The omission error found is high, but this is associated with landscape structure patterns, as found for the four reference images. The Product MCD45A1 even with spatial and temporal limitations promotes temporal mapping consistency and provides understanding the behavior and impacts of the burned on the Cerrado landscape. Among the Brazilian biomes, Cerrado is the one with the highest record of fires between 2002 and 2010 (73%), followed by Amazon (14%), while 81% of the records of the burned areas occur on the remnant vegetation cover class. The records of the burning recurrences in the Cerrado focus on the remnant class, 59% whereas the frequency of recurrence presented a higher proportion up to 3 times for the period 2000-2013. For the four groups of recurrences analyzed after the first fire record, 2002, the vegetative vigor records declines, especially after 2010, on average 4% for the remnant classes and 3.5% for the anthropogenic. The minimum distance between the fragments presents that 42% of recurrences analyzed are between 1-2 kilometers, providing greatest spatial concentration. / O fogo é um importante fenômeno ecológico e de perturbação ambiental no bioma Cerrado, o qual sofre influência de fatores climáticos, ecológicos, culturais e econômicos. A queima da biomassa promove a alteração da estrutura e composição do solo, acelera os processos erosivos e de sedimentação, promove a germinação de sementes, renovação das gramíneas e libera grandes quantidades de gases traços e aerossóis para a atmosfera. A presente pesquisa busca entender os padrões de localização e de recorrência das áreas queimadas para o bioma Cerrado, segundo suas diferentes regiões geográficas a partir das classes de uso da terra e cobertura vegetal remanescente e variáveis climáticas. Em específico busca-se avaliar quantitativamente a performance do produto MODIS MCD45A1 para o bioma Cerrado, de acordo com as distintas classes de uso e cobertura da terra em função da paisagem com base em 130 polígonos de áreas queimadas e 4 imagens orbitais de resolução espacial média, ambas amostras localizadas no mês de setembro. Outro interesse é de analisar os padrões espaciais e temporais da distribuição das áreas queimadas no território brasileiro considerando os limites territoriais dos biomas brasileiros e seus principais tipos de cobertura vegetal natural e antrópica (base PROBIO MMA), para tanto foi considerado os limites territoriais dos 6 biomas brasileiros (i.e. Amazônia, Caatinga, Cerrado, Mata Atlântica, Pampa e Pantanal). Por fim, avaliar os padrões (espaciais e temporais) e as frequências de recorrências das queimadas no Cerrado, com base em áreas queimadas >= 2km² e interseções >= 50% para as recorrências, bem como entender como a sazonalidade e variação interanual climática a partir dos dados de índice da vegetação (EVI), precipitação (TRMM) e evapotranspiração (MOD16) determinam os diferentes regimes de queima das várias classes de uso da terra e cobertura vegetal remanescente, para tanto foram analisados quatro grupos de recorrências com recortes temporais distintos. Os polígonos do produto MCD45A1 (setembro) apresentaram boa relação com o mapeamento de referência (base Landsat) (r² = 0.92) e também com os focos de calor (MOD14 e MYD14 - dados mensais) (r² = 0.89). O erro de omissão encontrado é alto, mas este está associado aos padrões de estrutura da paisagem, como o encontrado para as quatro imagens de referência. O Produto MCD45A1 mesmo apresentando limitações espaciais e temporais promove mapeamento com série temporal consistente, fornecendo entendimento do comportamento e os impactos do fogo sobre a paisagem do Cerrado. Entre os biomas brasileiros, o Cerrado é o que apresenta o maior registro de queimadas entre 2002 a 2010 (73%), seguido do Amazônico (14%), enquanto 81% dos registros das áreas queimadas ocorrem sobre as classes de cobertura vegetal remanescente. O registro das recorrências de queimadas no Cerrado se concentra sobre as classes remanescentes, 59%, já a frequência da recorrência apresenta maior proporção até 3 vezes para o período de 2000 a 2013. Para os quatro grupos de recorrências analisados, após o primeiro registro de fogo, 2002, o vigor vegetativo registra queda, principalmente após o ano de 2010, sendo em média 4% para as classes remanescentes e 3,5% para as antrópicas. A distância mínima entre os fragmentos mostra que 42% de recorrências analisadas estão entre 1 a 2 quilômetros, conferindo maior concentração espacial.
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Wildfire as Coupled Human Natural System

Farkhondehmaal, Farshad 01 February 2022 (has links)
Wildfire activity has increased in recent years in the United States, endangering both environment and society. Appropriate management of this phenomenon is only achievable with a thorough understanding of the critical factors influencing wildfire activity in each region. In three essays, I use statistical and mathematical models to examine wildfires and propose solutions to mitigate their impact on society. In the first essay, I focused on building a systematic framework for modeling wildfire as a coupled human-natural system. I employ system dynamics modeling, which was previously applied in various fields, including healthcare, sustainability, and disaster mitigation. I show how, in the absence of exogenous factors such as temperature or lightning, the human perception of fire danger may establish a feedback loop that can yield significant trends such as fluctuation or even fluctuation with rising amplitude when linked with the natural system. This conclusion is counter-intuitive, given that the human contribution to wildfire is typically described in the literature using constant or semi-constant variables. Additionally, I analyzed the impact of three important fire protection measures on reducing burning rates (prescribed burning, enhancing immediate suppression accomplishment, and regulating the rate of WUI growth). The research concludes that appropriately integrating several policies can result in a synergistic effect that is greater than the sum of the effects of the individual policies. The second essay calibrates the model built in the first essay and examines wildfire trends across the contiguous United States. The simulation results closely match the real data, and the model serves as a foundation for data-driven policy research. To be more precise, I fit the model to each state separately and then compare the model's goodness of fit. Following that, I examine the influence of various policies and scenarios on wildfire behavior. In the scenario, I examine the effect of maintaining constant temperatures and precipitation levels relative to the average values for these variables over the last century. For the policy analysis, I examine the influence of three policies on each state (prescribed burning, increasing immediate suppression achievement, and regulating the rate of WUI development). Here, I provide state-specific suggestions about the primary factors that contribute to wildfires and the most effective policies for each state. In the third essay, I have implemented the Oregon wildfire history dataset and integrated it with two other aerial datasets, including meteorological data gathered by weather stations located around the state and counties. Then, using hierarchical modeling on over 10,000 wildfire ignitions, I developed a classification system for determining if a given fire has the potential to grow major or not. However, utilizing a huge dataset and a variety of resources presents several obstacles, such as the presence of missing data. I imputed the missing numbers using a sophisticated mathematical approach called "Predictive Mean Matching". / Doctor of Philosophy / Wildfire activity has increased in recent decades in the United States, which put many people in danger. Climate change, the Settlement of people in the Wildland Urban Interface, and an increase in vegetation density each play a role in this increase. In this dissertation, we discuss the wildfire in the United States in three essays. In the first essay, we develop a mathematical model to show how humans and nature affect wildfire activity in any area. We then test different major wildfire management policies on the hypothetical situation to compare the outcome of these policies together. In the second essay, we use the model developed in the essay (with some minor changes) to model the wildfire activity in 11 states of the U.S. which has the most wildfire activity in recent years. First, we show that our model can replicate the wildfire activity in each state. Second, we test the effect of wildfire mitigation policies on each state. This essay proposes state-specific policy recommendations based on the main reasons for the increase in wildfire activity in each state. Finally, in the third essay, we develop a statistical model to predict the existence of large wildfires in the next month in Oregon counties. We use climate, land, and fire history data to develop a warning system. Policymakers can use this system to move the fire suppression resources to counties with a high probability of experiencing large wildfires over the next month. Finally, all essays aim to enhance our understanding of the reasons for the increase in wildfire activity in recent years and suggest finding the appropriate way to deal with this change to reduce the effect of wildfire on human life.

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