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Mapa de fragilidade ambiental: conceituação e aplicação em um setor do oleoduto São Paulo - Brasília (OSBRA) / Environmental fragility map: concept and aplication in São Paulo - Brasília oil pipeline (OSBRA)Filipe Biaggioni Quessada Gimenes 17 May 2013 (has links)
Atualmente existem diferentes definições para o conceito de fragilidade ambiental, o que dificulta sua aplicação e a comparação entre os resultados de diferentes métodos. Este trabalho realiza uma revisão bibliográfica sistemática a cerca desse conceito e adota a definição considerada mais adequada. Com base na definição adotada foi proposto e aplicado um método para avaliar a fragilidade ambiental de uma área de estudo. Esse método utiliza pesos para ponderar os diferentes atributos (meio físico, biótico e socioeconômico) envolvidos na análise de fragilidade ambiental, que são definidos com a aplicação do Processo de Análise Hierárquica (AHP). O método proposto também se fundamenta na utilização de um programa de Sistema de Informação Geográfica (SIG) para a estruturação da base de dados, a realização das análises espaciais e a ponderação dos mapas necessários. A área de estudo corresponde a um setor do oleoduto São Paulo – Brasília (OSBRA), com extensão de 18,5 km e largura de 2 km (área total de 83,99 km²) e utilizou-se uma base cartográfica digital na escala 1:10.000. Foram realizadas vistorias de campo para levantar pontos de observação de superfície e para coletar amostras de solo. Realizaram-se ensaios geotécnicos, químicos e mineralógicos com as amostras coletadas. A aplicação do método consistiu na geração de mapas de suscetibilidade intermediários, que combinados geraram o mapa de fragilidade ambiental. Foi importante a utilização do método AHP, pois ele reduz a subjetividade das ponderações qualitativas realizadas. Os resultados obtidos esclarecem a definição do conceito de fragilidade ambiental, além de mostrar a importância da seleção e ponderação dos atributos utilizados no método. O mapa final gerado também permitiu avaliar a sensibilidade do método e seu potencial de aplicação prática. / Currently there are different definitions to the concept of environmental fragility; it complicates its application and makes difficult to compare between different methods. This work addresses the main definitions to this concept and adopts the one considered the most proper. Based in the adopted definition it was proposed a method to evaluate the environmental fragility of a study area. This method applies weights to the different attributes (physical, biotic and socioeconomic) related to the environmental fragility analysis, which are assigned using the Analytic Hierarchy Process (AHP). The method also uses Geographic Information System (GIS) software to structure the database, to conduct the spatial analysis and to assign weights to the maps. The study area is a sector of the São Paulo – Brasília oil pipeline (OSBRA), covering 18.5 km length and 2 km wide (total area of 83,99 km²) and it was used a digital cartographic map at the scale of 1:10,000. Field trips were made to obtain surface observation points and to collect soil samples. Geological and geotechnical tests, mineralogical tests and chemistry analysis were conducted with the soil samples. The method application consists in generating intermediates susceptibility maps, that were combined to generate the environmental fragility map. It was important to use the AHP method, because it reduces the subjectivity of the qualitative weight assignment. The obtained results elucidate the environmental fragility concept and show the importance of the selection and weight assignment of the attributes used in the method. Moreover, the final map provided to evaluate the method sensitivity and its potential of practical application.
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Aplicação e comparação de metodologias de análise ambiental no trecho leste do Rodoanel Metropolitano de São Paulo / Aplication and comparison of methodologies for environmental analysis in the Section East of the São Paulo Metropolitan BeltwayCarlos Roberto Libonati Machado 24 October 2011 (has links)
Este trabalho visa aplicar e comparar duas metodologias de análise ambiental, a de Ross (1994) e a de Crepani et al. (2001), que abordam o ambiente dentro de uma perspectiva sistêmica, utilizando o conceito de Unidades Ecodinâmicas proposto por Tricart (1977). O objeto do presente trabalho é o Trecho Leste do Rodoanel Metropolitano de São Paulo, parte do anel viário concebido como uma alternativa ao tráfego de passagem pelo centro da Região Metropolitana de São Paulo, o qual o DERSA estabeleceu o traçado definitivo que será implantado a partir de setembro de 2011. Na geração dos documentos cartográficos analíticos e de síntese foram aplicadas técnicas de Geoprocessamento. Também foram utilizadas imagens de Sensoriamento Remoto para a extração de informações referentes à cobertura vegetal e uso do solo. Os mapeamentos de síntese e os traçados gerados automaticamente apresentaram resultados bem divergentes em razão do tratamento desigual das metodologias. Enquanto a proposta de Ross (1994) enfatiza a questão geomorfológica, basicamente as declividades, a metodologia de Crepani et al. (2001) adota uma equivalência entre as variáveis e é mais abrangente ao analisar o ambiente, apresentando uma maior compatibilidade com a área de estudo. Contudo, as variáveis ambientais possuem uma importância relativa, os aspectos econômicos e políticos parecem ter sido mais relevantes na definição do traçado final do Trecho Leste do Rodoanel. / This work aims to apply and compare two methods of environmental analysis, the Ross (1994) and the Crepani et al. (2001), that address the environment within a systemic perspective, using the concept of ecodynamics units proposed by Tricart (1977). The object of this work is the Section East of the São Paulo Metropolitan Beltway, part of the ring road designed as an alternative to traffic passing through the center of the São Paulo metropolitan region, which DERSA set the final route will be implemented from September 2011. In the generation of analytical and synthesis cartographic Geoprocessing techniques were applied. Were also used Remote Sensing images to extract information on land cover and land use. Mappings synthesis and the traces generated automatically showed conflicting results because of unequal treatment of methodologies. While the proposed Ross (1994) emphasizes the issue geomorphological, basically the slopes, the methodology of Crepani et al. (2001) adopts an equivalence between the variables and is more comprehensive in analyzing the environment, providing greater compatibility with the study area. However, environmental variables have a relative importance, the economic and political aspects seem to have been more relevant in defining the final route of the Section East of the Beltway.
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As abordagens sistêmica e do equilíbrio dinâmico na análise da fragilidade ambiental do litoral do Estado de São Paulo: contribuição à geomorfologia das planícies costeiras / Systemic approaches and the dynamic equilibrium in the analysis of environmental fragility of the coast of the state of S Paulo: contribution of geomorphology of coastal plainsMarisa de Souto Matos Fierz 10 December 2008 (has links)
A presente pesquisa tem como objetivo principal avaliar, por meio da abordagem sistêmica e do equilíbrio dinâmico, as diferenças de configurações geológicas e geomorfológicas e de fragilidade nos variados compartimentos geomorfológicos ao longo das planícies costeiras na enseada da Fortaleza, em Ubatuba, litoral norte de São Paulo e região de Peruíbe-Itanhaém, litoral centro-sul de São Paulo. Essas diferenças de configurações morfológicas são resultantes de processos pretéritos e do arcabouço geológico que sustentam as formas manifestadas na paisagem, moldadas pelos processos que atuam como agentes modeladores e de manutenção do equilíbrio dinâmico dessas formas. O equilíbrio dinâmico, nos moldes ecogeográficos de Tricart (1977), é mantido pela cobertura vegetal que pode manter constantes os processos de morfogênese e pedogênese ao longo da planície costeira que constituída de material friável, areias finas a muito finas que lhes conferem, a princípio, um caráter de fragilidade intrínseca. O equilíbrio dinâmico nos moldes geomorfológicos de Hack (1960, 1965) é mantido pela variação da resistência dos materiais que compõem o relevo, sustentando as formas. Essas duas abordagens auxiliaram na determinação da fragilidade ambiental, que é identificada e representada, sobretudo, pelas variações de resistência entre os diversos compartimentos ou subsistemas geomorfológicos mapeados ao longo da planície. Entretanto, em alguns trechos da planície costeira, sobretudo no litoral sul, onde o solo do tipo espodossolo apresenta horizonte B espódico também denominado, nesta tese, de fragipã (?), cuja principal característica é de caráter endurecido pela composição de ácidos húmicos e fúlvicos, retidos ali pelo processo de podzolização. Nestes trechos, os testes de resistência resultaram em poucos impactos de penetração ou nulos. O horizonte B espódico rígido, destarte a classificação da fragilidade ambiental obteve diversidades influenciadas pelas características desses trechos de espodossolos e por apresentarem interferências diretas nos processos de mudanças dos níveis topográficos. / The principal aim of this research, based on the Systems Approach and on the Dynamic Equilibrium, is to evaluate geological and geomorphologic different configurations and environmental fragility on the several geomorphologic topographic features in the coastal plains of Fortaleza bay in Ubatuba, located in the north coast of São Paulo and Peruíbe-Itanhaém area, located in center-southern coast of the São Paulo State.These morphological configurations differences are result of the geologic past processes and the geologic structure that sustain the stamped landscapes forms by active processes that behave as modeling agents and of maintenance of the dynamic equilibrium of this forms.The dynamic equilibrium by ecogeography principles of Tricart (1977) is maintained by the vegetal cover that prolong constant the process of morphogenesis and pedogenesis for all coastal plain that is mainly formed by material, thin to very thin sand particles that gives the region character of intensive fragility.The dynamic equilibrium on the geomorphologic models of Hack (1960, 1965) is maintained by the materials resistance variation that composes the reliefs forms. These both examples help in the determination of the environmental fragility that is identified and represented, mainly by the variations of the resistance among the various compartments geomorphologic or subsystems mapped throughout coastal plain. In some parts of the coastal plain, mainly in the south shore, where the kind of soil is Espodossoil presents level B espodic, also denominated as fragipã (?), which the principal characteristic is present by the character hardened by the composition of the humic and fulvic acids, retained there by the podzolization process. In these places the resistance tests resulted in few or null impacts penetration. The hardened level B espodic, regardless classification of the environmental fragility, showed direct interferences in the process of the changes on the topographic levels.
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Fragilidade ambiental à erosão laminar na bacia hidrográfica do córrego São Domingos, em Ubá/MGSantos, Vitor Juste dos 08 April 2016 (has links)
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Previous issue date: 2016-04-08 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Ubá está localizado na porção sudeste do Estado de Minas Gerais, na mesorregião da Zona da Mata, sendo polo de uma microrregião composta por 17 municípios. Ubá é a área “core” da microrregião, possuindo diversificada oferta de produtos, bens e serviços, o que gera uma significativa concentração econômica e demográfica, e a diferencia consideravelmente da maior parte das cidades localizadas à sua volta. Demograficamente, tal situação fica evidente a partir dos dados de população apresentados pelo Instituto Brasileiro de Geografia e Estatística (IBGE) e disponibilizados pelo Instituto de Pesquisa Econômica Aplicada (IPEA), que demonstram um desproporcional adensamento da população microrregional na cidade de Ubá e que tem importantes consequências no crescimento da cidade ubaense. O aumento acentuado da população urbana resultou na expansão da ocupação para áreas de encostas, muitas delas com declividades elevadas. Isso provavelmente intensificou a ação dos processos erosivos, devido à exposição dos solos nessas áreas. A Bacia Hidrográfica do Córrego São Domingos (BHCSD), área de estudo da presente pesquisa, constitui um dos vetores de crescimento urbano da cidade de Ubá. Com a abertura de loteamentos, as áreas de solos expostos dentro da bacia aumentarão consideravelmente, o que pode aumentar a ocorrência de processos erosivos. A metodologia proposta por Ross (1990; 1994) foi escolhida para avaliar e mapear a fragilidade da área estudada em relação à erosão laminar dos solos. Então, o objetivo geral desta pesquisa é identificar as diferentes fragilidades aos processos erosivos na BHCSD, desde as áreas mais frágeis as menos frágeis, com base na metodologia daquele autor. Constatou-se, que as áreas de encostas são as mais frágeis em relação aos processos erosivos laminares, pois são as que possuem as maiores declividades da bacia e superfícies com solos expostos, principalmente pela abertura de loteamentos e devido a processos erosivos intensos em curso. Já as áreas menos frágeis são as planícies de inundação, pois possuem as menores declividades, e suas superfícies estão altamente impermeabilizadas devido ao processo de urbanização. Contudo, são as áreas que mais recebem sedimentos de montante, causando entupimento da rede de drenagem, sujando as ruas, assoreando os cursos d’águas, entre outras consequências, que são responsáveis por intensificar problemas como os alagamentos e as inundações. / Ubá is located in the southeastern portion of the State of Minas Gerais, in the middle region of the Zona da Mata. It is polo of a micro-region of 17 municipalities. Ubá is the core area of the micro-region, having diversified range of products, goods and services, which generates a significant economic and demographic concentration, and differs considerably from most towns located around it. Demographically, this situation is evident from the population data provided by the Instituto Brasileiro de Geografia e Estatística (IBGE) and made available by the Instituto de Pesquisa Econômica Aplicada (IPEA), which show a disproportionate density of micro-regional population in the city of Ubá and has important consequences on the growth of the city. The sharp increase of the urban population has resulted in the expansion of occupation to areas of hillsides, many with high steepness. This probably intensified the action of erosion due to exposure of the soil in these areas. The Bacia Hidrográfica do Córrego São Domingos (BHCSD), study area of this research, is one of the urban growth area of the city of Ubá. With the opening of allotments, areas of exposed soils within the basin will increase considerably, which could increase the occurrence of erosive processes. The methodology proposed by Ross (1990, 1994) was chosen to assess and map the fragility of the studied area in relation to soil sheet erosion. So, the objective of this research is to identify the different fragilities to erosion in BHCSD, from the most fragile areas at less fragile, based on that author methodology. It was found that the areas of the slopes are the most fragile in relation to sheet erosion, as are those with the highest slopes of the basin and surfaces exposed soils, particularly by the opening of allotments and due to intense erosive processes underway. As for the less fragile areas are the flood plains, because have the smaller slope and their surfaces are highly impermeable due to the urbanization process. However, are the areas that receive the most amount of sediment, causing clogging of the drainage system, littering the streets, obstructing the water courses, among other consequences, which are responsible for intensifying problems such as flooding.
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Silent slips, trips and broken hips : the recovery experiences of young adults following an isolated fracture of the proximal femurJanes, Gillian January 2016 (has links)
Isolated hip fracture following a minor fall is a serious injury, normally requiring urgent surgical treatment and a complex recovery journey. Although commonly associated with the elderly, incidence and impact in adults under 60 years of age may be underestimated. The extensive literature almost exclusively focuses on the elderly, surgical interventions and relatively short-term outcomes. Young adults are also missing from the dominant societal discourse and healthcare policy on fragility hip fracture. They therefore represent a silent sub-subset of the fragility hip fracture population, whose recovery experiences and needs, particularly in the longer term, remain largely unknown. A critical interpretivist approach and The Silences Framework (Serrant-Green, 2011), were used to ‘give voice’ to young adults with isolated hip fracture. Thirty participants, between one and ten years post injury, completed an in-depth, minimally structured interview in which they told their story of recovery. An inductive, thematic analysis was undertaken integrating Braun and Clarke (2006) and the four phase cyclical analysis of The Silences Framework (Serrant-Green, 2011). One cross-cutting theme: Communication emerged, together with four other main themes: Experience of care, Impact on self, Impact on others and Moving forward. 11 The findings indicated wide variation in the quality of care, often influenced by social and professional norms regarding hip fracture patient characteristics such as age and mode of injury. Multi-faceted, often long term, physical, social and psychological impact on participants, their family and wider social networks was also found. This included Post Traumatic Stress Disorder type symptoms and impact on work, finances and relationships. The study highlighted some limitations of the current hip fracture care pathway for supporting the specific recovery needs of young adults. It also identified some limited effectiveness of commonly used patient reported outcome measures for hip fracture in this young client group. Exploring the recovery experiences of this under-represented group confirmed, but also altered the silences initially identified. Furthermore, it uncovered new silences which informed recommendations for future research; healthcare practice and policy. This study offers the first long term exploration of the impact of isolated hip fracture following a minor fall in young adults from their perspective. In doing so, it has also demonstrated the appropriateness of The Silences Framework (Serrant-Green, 2011) for guiding a person-centred, experience-based, acute orthopaedic/rehabilitation study undertaken by a student researcher.
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Bone adaptation to impact loading—Significance of loading intensityVainionpää, A. (Aki) 05 June 2007 (has links)
Abstract
Ageing populations have made osteoporosis and fragility fractures a major public health concern worldwide. Half of all women and 30% of all men will suffer a fracture related to osteoporosis during their lifetime. While medical prevention of this immense problem is impossible at population level, it is necessary to find efficient preventive strategies. Exercise is one of the major prevention approaches because one reason behind the increasing burden of osteoporosis is the modern sedentary lifestyle. However, the optimal type, intensity, frequency, and duration of exercise that best enhances skeletal integrity are still largely unknown.
We conducted a 12-month population-based randomized controlled exercise intervention in 120 premenopausal women. The aim was to investigate the effect of impact exercise on bone mineral density, geometry and metabolism in healthy women with the intention of assessing the intensity and amount of impact loading with a novel accelerometer-based measurement device. Training effects on risk factors of osteoporotic fractures, physical performance and risk factors of cardiovascular diseases were also evaluated.
This study demonstrated that 12 months of regular impact exercise favoured bone formation, increased bone mineral density in weight-bearing bones, especially at the hip, and led to geometric adaptations by increasing periosteal circumference. Bone adaptations had a dose- and intensity-dependent relationship with measured impact loading. Changes in proximal femur were threshold-dependent, indicating the importance of high impacts exceeding acceleration of 4 g as an osteogenic stimulus. The number of impacts needed to achieve this stimulation was 60 per day. Impact exercise also had a favourable effect on physical performance and cardiorespiratory risk factors by increasing maximal oxygen uptake, dynamic leg strength and decreasing low-density lipoproteins and waist circumference. Changes were dose-dependent with impact loading at wide intensity range.
Bone adapts to impact loading through various mechanisms to ensure optimal bone strength. The number of impacts needed to achieve bone stimulation appeared to be 60 per day, comparable to the same number of daily jumps. If done on a regular basis, impact exercise may be an efficient and safe way of preventing osteoporosis. / Tiivistelmä
Väestön ikääntymisen ja elintapojen muutosten myötä osteoporoosista ja osteoporoottisista murtumista on tullut maailmanlaajuinen terveysongelma. Ongelman laajuuden vuoksi murtumien lääkkeellinen ehkäisy ei ole mahdollista kattavasti väestötasolla, joten vaihtoehtoisten ehkäisymenetelmien kehittäminen on välttämätöntä. Liikunta on yksi potentiaalinen ehkäisykeino, koska yksi tärkeä tekijä ongelman taustalla on arkiliikunnan vähentyminen. Liikunnan tiedetään hyödyttävän luustoa, mutta optimaalisen liikunnan tyyppi, intensiteetti, määrä ja kesto ovat kuitenkin selvittämättä.
Tämän tutkimuksen tavoitteena oli selvittää hyppyharjoittelun vaikutusta 35–40-vuotiaiden naisten luun tiheyteen, geometriaan ja aineenvaihduntaan sekä määrittää luun kannalta optimaalisen harjoittelun määrä ja voimakkuus. Tutkimuksessa selvitettiin myös harjoittelun vaikutuksia fyysiseen suorituskykyyn, sekä sydän- ja verisuonisairauksien riskitekijöihin. Toteutimme väestöpohjaisen, satunnaistetun, kontrolloidun 12 kuukauden mittaisen liikuntaintervention, johon osallistui 120 naista. Intervention aikana mittasimme hyppykuormitusten määrää ja voimakkuutta uudella kiihtyvyysanturiin perustuvalla menetelmällä. Nousujohteinen hyppyharjoittelu aiheutti kuormitetuissa luissa muutoksia, joista keskeiset olivat luuntiheyden ja luun ympärysmitan kasvu. Lisäksi luuston aineenvaihdunnassa tapahtui muutoksia, jotka osoittivat luun uudismuodostuksen lisääntyneen. Luun mukautumisen ja mitattujen iskukuormitusten välillä havaittiin annos-vastesuhde. Kuormitusten voimakkuus oli olennaista, sillä reisiluun kaulan luuntiheyden muutokset olivat yhteydessä kuormituksiin, joiden kiihtyvyys oli yli 4 kertaa maan vetovoiman (g) suuruinen. Luustomuutoksen saavuttamiseen tarvittavien kuormitusten määrä yli 4 g:n tasolla oli kuitenkin vain 60 kuormitusta vuorokaudessa, jotka voidaan turvallisesti saavuttaa normaaleilla hypyillä. Liikuntaharjoittelu paransi myös kolesteroliarvoja, maksimaalista hapenottokykyä, voimatasoja sekä pienensi vyötärön ympärystä, vaikuttaen näin positiivisesti sydän- ja verisuonisairauksien riskitekijöihin.
Tutkimus osoitti luun mukautuvan muuttuneisiin kuormituksiin useiden mekanismien kautta ja mukautumisen olevan kuormitusten intensiteetistä riippuvaista. Osteoporoosin ehkäisyn kannalta tehokas ja turvallinen kuormitusmäärä näyttää olevan 60 hyppyä päivässä.
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Étude de la vulnérabilité des bâtiments en maçonnerie soumis à des mouvements de terrains et élaboration de critères d’évolution de leur rigidité / Study of the vulnerability of masonry buildings subjected to ground movements and elaboration of their stiffness evolution criteriaSerhal, Jamil 13 April 2016 (has links)
L’objectif principal de cette recherche est l’étude du dommage des bâtiments en maçonnerie subissant des tassements différentiels. Cette contribution, en s’appuyant sur la modélisation numérique, les méthodes analytiques et sur l’expérimentation, vise à une meilleure compréhension du comportement des structures en maçonnerie. Ce problème trouve diverses applications en ingénierie avec par exemple les maisons situées dans des zones de creusement de tunnels, ou des zones subissant des affaissements de terrains. L’étude bibliographique met en évidence la diversité des méthodes permettant de catégoriser le dommage des bâtiments subissant des tassements. La cohérence de ces méthodes est étudiée. En particulier, le travail porte sur l’étude de l’influence des propriétés mécaniques des bâtiments sur les valeurs seuils proposées pour catégoriser le dommage. Une étude de sensibilité est mise en œuvre afin de proposer des intervalles de seuils dépendant des propriétés des bâtiments. Cette incertitude est alors formalisée par le développement de courbes de fragilité permettant de quantifier en terme de probabilité la sévérité du dommage pour différents types de bâtiments. En addition, la rigidité des bâtiments subissant des mouvements de terrains est un paramètre important pour étudier les phénomènes d’interaction sol-structure et évaluer les tassements différentiels transmis par le terrain aux structures. L’évolution de cette rigidité en fonction du dommage associé aux tassements n’est pas étudiée dans la littérature. Une méthodologie d’étude de la variation de la rigidité des bâtiments en maçonnerie en fonction du tassement transmis a été développée au moyen de modélisations numérique (logiciel UDEC). Des formulations analytiques sont alors proposées pour relier la réduction de la rigidité des bâtiments en fonction du tassement subis et de leurs propriétés. Une procédure expérimentale est mise en place afin de valider la méthodologique numérique. En conclusion, les deux principales contributions de cette thèse sont 1) une amélioration de l’évaluation du dommage des bâtiments en fonction de leurs propriétés, au moyen des courbes de fragilité et 2) le développement d’une méthodologie numérique permettant d’évaluer l’évolution de la rigidité des bâtiments en maçonnerie en fonction du tassement qu’ils subissent et en fonction de leurs propriétés / The main purpose of this research is the assessment of the damage of masonry buildings undergoing differential settlements. This contribution, which is based on numerical modeling, analytical methods and experimentation, aims for a better understanding of the behavior of masonry structures. The treated issue may be applied in different engineering fields, as for example the case of buildings located in tunneling areas or in areas suffering land subsidence. The bibliography survey presents a diversity of methods to categorize the damage of buildings undergoing settlement. This variety of methods, parameters and thresholds used to qualify the severity of the damage, prompted us to study the consistency of these methods, and the effect of the properties of masonry buildings - undergoing ground movements - on proposed threshold values. A sensitivity analysis on building properties is implemented in order to propose thresholds values intervals that depend on buildings properties. This uncertainty is then taken into account with the development of fragility curves that aim quantifying the damage in terms of probability according to a typology of buildings. In addition, the stiffness of buildings undergoing ground movements plays a very important role in studying the phenomenon of soil-structure interaction. However, the evolution of the stiffness of the damaged building due to settlements is not investigated in the literature. Numerical modeling (UDEC) is used to develop a methodology for the study of the stiffness variation of masonry buildings in relation to he settlement suffered by the structure. Analytical formulations are proposed to relate the reduction of the stiffness of the buildings with regard to the suffered settlement, and depending on the buildings properties. Some experimental tests are performed to validate the numerical methodology. Finally, the two mains results are 1) improvement in the assessment of buildings damage with the drawn of fragility curves and 2) the numerical methodology to formulate the changes in the stiffness of masonry buildings according to the suffered settlement, and according to their properties
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EXPECTATIONS IN MACROECONOMICS: PERSPECTIVES, LABORATORY EXPERIMENTS AND AB MODELSTETTAMANZI, MICHELE 22 December 2017 (has links)
La presente tesi studia le aspettative in macroeconomia contribuendo alla letteratura esistente sia indagando circa il meccanismo di formazione delle aspettative, sia analizzando come le aspettative a razionalità limitata influenzino la dinamica economica.
Nel primo capitolo viene presentato un esperimento nel quale ai soggetti viene chiesto di predire il valore futuro dell'inflazione: a seconda del trattamento, i soggetti possono venire esposti ad un segnale, che mira a stabilizzare l'economia, che fungendo quindi da indicazione prospettica (Forward Guidance). I risultati vengono poi studiati sottolineando il meccanismo di formazione delle aspettative soprattutto in funzione della credibilità del segnale; inoltre viene studiata l'efficacia dello strumento di politica monetaria nella stabilizzazione del sistema economico: si evidenzia come un segnale informativo permetta una sensibile stabilizzazione dell'economia, prevenendo spirali deflazionistiche.
Nel secondo capitolo viene sviluppato un modello ad agenti il quale incorpora un meccanismo di formazione delle aspettative a razionalità limitata, derivato da esperimenti precedenti. Inoltre, grazie ad un peculiare processo di aggregazione, viene derivato un modello analiticamente trattabile che permette di studiare il meccanismo di trasmissione di uno shock, isolando gli effetti dovuti all'eterogeneità fra gli agenti e alle aspettative: entrambi gli effetti sono considerevoli ed aiutano nello spiegare la dinamica economica. / The present dissertation analyses expectations in macroeconomics, contributing to the existing literature both studying the expectation formation process, and inquiring how economic dynamic is influenced by boundedly rational expectations.
The first chapter presents a learn to forecast experiment in which subject are asked to form expectation regarding the future value of inflation: depending on the treatment, subjects might be exposed to a signal, which possibly aim at stabilizing economy, mimicking the non conventional monetary policy instrument called Delphic Forward Guidance. The collected data are studied trying to recover the underlying expectation formation process highlighting especially the role of credibility of the signal; moreover from the data emerges that informative Forward Guidance helps in stabilizing economy, drastically reducing the probability of deflationary spirals.
The second chapter develops an agent-based model, encapsulating a boundedly rational expectation formation process, which had been extrapolated in previous experiments. Moreover benefiting from a specific aggregation procedure, we derive a model characterized by high analytical tractability, allowing hence to study the transmission mechanisms of a shock by insulating the effects due to the heterogeneity among agents and due to expectations: both the effects are sizable and help in understanding the dynamics of the economic system.
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La vulnérabilité des ouvrages soumis aux aléas mouvements de terrains ; développement d'un simulateur de dommages / Development of a damage simulator for evaluation of buildings vulnerability due to ground movementsSaeidi, Ali 12 February 2010 (has links)
L’objectif de cette thèse a été de concevoir et développer un simulateur de dommages permettant d’étudier la vulnérabilité d’un territoire soumis à des aléas de mouvements de terrains associés à la présence d’exploitations souterraines. Ce développement repose sur la combinaison d’une méthode de prévision des affaissements miniers, de fonctions de vulnérabilité pour l’évaluation des dommages et d’une base de données des bâtiments. L’enjeu scientifique est le développement de fonctions de vulnérabilité pour les bâtiments en zone d’affaissement minier. Ces fonctions sont comparables à celles utilisées vis-à-vis d’autres aléas comme les séismes et les tsunamis. On a développé et appliqué une méthodologie basée sur des simulations de type Monte-Carlo qui utilise les méthodes existantes d’évaluation des dommages dans les zones d’affaissement minier (méthodes empiriques ou analytiques). Elle permet de prendre en compte l’incertitude sur les paramètres géométriques et mécaniques du bâti. Afin de valider cette méthodologie, les dommages estimés par les fonctions vulnérabilité développées pour des bâtiments en maçonnerie du bassin ferrifère lorrain sont comparées aux dommages observés, consécutifs aux affaissements de 1996 à 1999 en Lorraine. Dans une étape suivante, la méthode des fonctions d’influence a été implémentée dans le simulateur avec certains développements permettant de tenir compte de la variabilité des angles d’influences et permettre le calcul des déformations horizontales du terrain. Les résultats de cette méthode sont validés sur un cas d’affaissement observé dans le bassin ferrifère de lorrain. Enfin, une approche probabiliste d’évaluation des dommages est implémentée pour tenir compte de différents scénarios d’affaissement possibles. L’application sur les bâtiments de la ville de Joeuf, permet d’illustrer les différents résultats obtenus / The objective of this thesis has been the design and the development of a damage simulator for evaluation of building damage in subsidence regions affected by undergrounds excavations. The simulator is combining a method for the subsidence prediction, vulnerability functions for assessment of building damage and a database of buildings. The scientific challenge is the development of vulnerability functions for buildings in subsidence regions. These functions are similar to those used for other hazards such as earthquakes and tsunamis. We then developed and applied a methodology based on Monte-Carlo simulations which involves existing methods of building damage assessment in subsidence area (empirical or analytical methods). It allows to take into account uncertainties on both geometrical and mechanical parameters of buildings. To validate this methodology, damages given by the vulnerability functions developed for masonry buildings in the Lorraine Iron ore field are compared to observed damages, resulting from subsidence from 1996 to 1999 in Lorraine. In a next step, the method of influence functions is implemented in the simulator with developments to take into account variability of the influence angles and to allow the calculation of horizontal ground strain. Results of this method are validated with a subsidence case study in the Lorraine iron ore field. Finally, a probabilistic approach to assess damage is implemented in the simulator to take into account different scenarios of possible subsidence. The application of the simulator on the buildings of the Joeuf city, allows to illustrate the different results
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Urbanização e fragilidade ambiental na Bacia do Corrego Proença, Municipio de Campinas (SP) / Urbanization and environmental fragility in the basin drainage, Proença Municipality of Campinas (SP)Vilela Filho, Luis Ribeiro 21 August 2006 (has links)
Orientador: Antonio Carlos Vitte / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Geociencias / Made available in DSpace on 2018-08-07T09:24:41Z (GMT). No. of bitstreams: 1
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Previous issue date: 2006 / Resumo: o acelerado processo de expansão urbana verificado nas últimas décadas, particularmente nas grandes cidades brasileiras, fez com que os chamados problemas ambientais urbanos se avolumassem de forma generalizada. Dentre esses problemas, a questão das enchentes tem se constituído em um dos mais relevantes por acarretar danos socioambientais por vezes irremediáveis. Em sua gênese, a incidência de enchentes em áreas urbanas está associada às circunstâncias em que se consolida a apropriação do espaço urbano, que em geral são baseadas em posturas pouco abrangentes da gestão pública, na medida em que essas intervenções são regidas por interesses particulares em detrimento das características e propriedades do espaço natural. Essas intervenções alteram e desestabilizam o sistema natural, fazendo com que sua dinâmica passe a responder a novos estímulos e processos, podendo resultar na ftagilidade do sistema, uma vez que, no meio fisico a fragilidade está associada à suscetibilidade desse meio sofrer alterações. Nesse contexto, o objeto de estudo deste trabalho é a bacia de drenagem do córrego Proença, situada nas imediações da área central da cidade de Campinas (SP) que, em função de um modelo de planejamento associado a uma lógica especulativa imobiliária, atrelada ao poder local, acabou por gerar um intenso e denso processo de urbanização na bacia, que acarretou em profundas intervenções no seu sistema natural, provocando seu desequilíbrio, o qual se reflete nas constantes situações de enchentes ocorridas anualmente na bacia. Tendo em vista estas questões, o objetivo deste trabalho é caracterizara situação de risco às enchentes na bacia do córrego Proença, a partir da relação entre a fragilidade potencial do relevo, e o processo de produção do espaço urbano em Campinas. Nesse sentido, a correlação entre os índices morfométricos obtidos possibilitou a identificação dos setores de fragilidade potencial da bacia, de tal forma que, a associação entre o modelo de gestão urbana adotado para a cidade, onde priorizaram-se as intervenções viárias e funcionais no sentido de favorecer a especulação imobiliária em detrimento dessas propriedades morfométricas do espaço natural, resultou em situações de risco à enchentes bacia do córrego Proença / Abstract: The acceleratered urban expansion process that took place during the last decades in most of Brazilian metropolis, made the so-called urban environmental problems increase in a generalized way. Among those problems, floods have become one of the most relevant since it may cause social-environrnentalhazards, which are, sometimes, incurable. The incidence of floods in urban areas is associated to the circumstances consolidated by the use of the urban space, generally based on not so wide-ranging public policies, since those interventions are ruled by private interests rather than the characteristics and specifíc aspects of the natural area.
Such interventions alter and make the natural system unstable, so that its dynamics react to the new stimulus and processes, resulting in its ftagility, since in the physical environrnent this fragility is associated to its susceptibility ofundergoing changes. In this context, the focus of present study is the Basin Drainage Proenca, located around the downtown area Campinas (SP) which, due to a planning scheme associated to logic speculative real state aflàirs, connected to local power, caused a great urban process around the basin area which led to a deep impact in its natural system, thus causing unstable status reflected by the ftequent and high incidence of floods that annually take place. Based in the above statement, the aim of study was characterize the situations of risks related to
floods in the Basin Proenca, taking into account the relationship between the fragile terrain and the urban developing process in Campinas. The correlation between the morphemics rate found in this study enabled the identification of potential fragile areas in the basin in such a way that, the association between urban management models used by local govemment, where the intervention of roads are given more attention in order to favor real state speculation rathen than to the morphemics characteristic of the natural
area, resulted in the situation of risks of floods in the Basin Proença / Mestrado / Análise Ambiental e Dinâmica Territorial / Mestre em Geografia
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