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Évaluation de la microarchitecture trabéculaire et des propriétés mécaniques osseuses in vivo chez l’humain par scanner périphérique a haute résolution : application clinique à l’ostéoporose / In vivo assessment of trabecular microarchitecture and bone biomechanical properties by high resolution peripheral quantitative tomography : application to osteoporosisVilayphiou, Nicolas 16 December 2010 (has links)
La microarchitecture osseuse est un des déterminants de la qualité osseuse qui peut maintenant être évaluée in vivo au radius et au tibia distaux avec une résolution isotropique de 82μm par un nouveau scanner à haute résolution (XtremeCT, SCANCO Medical AG). Par ailleurs, l’utilisation d’analyse en éléments finis sur les volumes 3D obtenus permet d’évaluer les propriétés biomécaniques de l’os comme la résistance osseuse. Nous avons montré qu’il s’agissait d’une technique prometteuse pour évaluer la densité, la microarchitecture et les propriétés biomécaniques osseuses au niveau des sites périphériques, notamment parce que ces mesures étaient associées chez la femme avec des fractures ostéoporotiques de toutes sortes. Nous avons également montré que les mêmes mesures étaient tout aussi pertinentes chez l’homme, alors qu’il est moins sujet à l’ostéoporose. Les résultats étaient associés aux fractures ostéoporotiques de toutes sortes, notamment les fractures vertébrales. L’analyse en éléments finis permet donc la mesure in vivo de la résistance osseuse, ce qui pourrait fournir des informations sur la fragilité osseuse et le risque de fracture non accessible par les seules mesures de densité ou de microarchitecture osseuse. / Bone microarchitecture is one of the determinants of bone quality that can now be evaluated in vivo at the distal radius and tibia with an isotropic resolution of 82μm with a new high-resolution peripheral scanner (XtremeCT, SCANCO Medical AG). Moreover, the use of finite element analysis on the 3D bone volume acquired allows the assessment of bone biomechanical properties such as bone strength. Our studies show that this technique is promising to assess bone density, microarchitecture and strength at peripheral skeletal sites. Indeed those measures were associated with osteoporotic fractures of all kinds in women. We also demonstrated that those same measures were associated with osteoporotic fractures of all kinds, including vertebral fractures, in men, who are less prone to be affected by osteoporosis. Finite element analysis allows in vivo measurement of bone strength, which might provide additional information about bone fragility and fracture risk that are not assessed by measures of density or microarchitecture.
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Méthodes de construction des courbes de fragilité sismique par simulations numériques / Development of seismic fragility curves based on numerical simulationsDang, Cong-Thuat 28 May 2014 (has links)
Une courbe de fragilité sismique qui présente la probabilité de défaillance d’une structure en fonction d’une intensité sismique, est un outil performant pour l’évaluation de la vulnérabilité sismique des structures en génie nucléaire et génie civil. On se concentre dans cette thèse sur l’approche par simulations numériques pour la construction des courbes de fragilité sismique. Une étude comparative des méthodes paramétriques existantes avec l’hypothèse log-normale est d’abord réalisée. Elle permet ensuite de proposer des améliorations de la méthode du maximum de vraisemblance dans le but d’atténuer l’influence de l’excitation sismique lors de son processus de construction. Une autre amélioration est l’application de la méthode de simulations par subsets pour l’évaluation de la probabilité de défaillance faible. Enfin, en utilisant la méthode de calcul de l’évolution des fonctions de densité de probabilité qui permet d’évaluer la probabilité conjointe entre la réponse structurale et les variables aléatoires du système et de l’excitation, nous proposons également une nouvelle technique non-paramétrique de construction des courbes de fragilité sismique sans utiliser l’hypothèse de la loi log-normale. La validation des améliorations et de la nouvelle technique est réalisée sur des exemples numériques. / A seismic fragility curve that shows the failure probability of a structure in function of a seismic intensity is a powerful tool for the evaluation of the seismic vulnerability of structures in nuclear engineering and civil engineering.We focus in this thesis on the numerical simulations-based approach for the construction of seismic fragility curves. A comparative work between existent parametric methods with the lognormal assumption of the fragility curves is first performed. It then allows proposing improvements to the maximum likelihood method in order to mitigate the influence of seismic excitation during its construction process. Another improvement is the application of the subsets simulation method for the evaluation of the low probability of failure. Finally, using the Probability Density Evolution Method (PDEM) for evaluating the joint probability between a structural response and random variables of a system and/or excitations, a new technique for construction of seismic fragility curves was proposed. The seismic fragility curve can be derived without the assumption of lognormal law. The improvements and the new technique are all validated by numerical examples.
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Solidité et pérennité des banques de l'Union économique et monétaire ouest-africaine (UEMOA)Ndiaye, Malick Paul 17 April 2015 (has links)
Ces dernières décennies ont été marquées par une succession de crises financières qui trouvent principalement leur origine ou ont été amplifiées par les systèmes bancaires. L'importance du secteur bancaire dans tout processus de développement économique a fait que les crises se sont considérablement ressenties dans la sphère réelle. Le rebondissement et l'extension des crises ont ravivé le débat sur la solidité et la pérennité des banques. Afin d'améliorer la stabilité du système bancaire international et de supprimer les distorsions de concurrence entre pays, le Comité de Bâle sur le Contrôle Bancaire a formulé en 1988 un ensemble de règles prudentielles. La réglementation du capital bancaire est au coeur du dispositif réglementaire. La Commission Bancaire de l' UEMOA s'en est inspirée dans l'élaboration d'un certain nombre de règlements définissant les principales normes minimales de solvabilité, de liquidité et de gestion. L'objet de cette thèse est une réflexion sur les modalités de la solidité et de la pérennité des systèmes bancaires dans les pays de la zone UEMOA. La thèse soulève ainsi plusieurs questions : comment prévenir le risque de défaillance des banques de l' UEMOA à travers un contrôle des variables de structure ? Quels sont les facteurs explicatifs de la rentabilité des banques de la zone UEMOA ? Le CAMEL peut-il être considéré comme un bon système d'alerte précoce des difficultés bancaire dans la zone ? Quel est le niveau d'efficacité des banques de l' UEMOA ? Chaque question fait l'objet d'un essai dans la thèse.Dans le premier essai, le z-score de ROY (1952) est utilisé comme indicateur du risque de défaillance bancaire, et la Méthode des Moments Généralisés comme méthode d'estimation. Dans le deuxième essai, les marges d'intermédiation sont considérées comme proxy de la rentabilité bancaire. Chaque pays ayant ses propres spécificités une estimation sur données de panel à effets spécifiques individuels est adoptée. Dans le troisième essai, un modèle dichotomique qui fait la distinction entre banques en bonne santé et banques probablement fragiles est utilisé et une forme fonctionnelle logistique. Dans le dernier essai, l'approche paramétrique des frontières stochastiques avec une spécification translogarithmique est utilisée pour estimer la fonction de coût total des banques et pour déterminer les scores d'efficacité des banques. / Recent decades have been marked by a succession of financial crisis which are mainly caused or deepen by the banking system. Banking has such an impact on economic growth process that crisis have had direct drawbacks on real life. The length and extent of crisis have raised the debate about the reliability and sustainability of banking. To improve the stability of the internationalbanking system and to put an end to unfair competition between countries, the Basel Committee on Banking Supervision in 1988 made a set of prudential rules. The regulation of bank capital is at the center of the regulatory system. The WAMU Banking Commission has drawn inspiration in the development of a number of regulations defining the key minimum standards solvency, liquidity and management.This thesis is a reflection on the terms of the strength and sustainability of the banking systems in countries of the WAEMU zone. The thesis thus raises several questions : how to prevent the risk of failure-bankrupcy- of WAEMU banks through a control of structural factors ? What are the factors explaining the profitability of banks in the WAEMU zone ? Can the CAMELS be considered as a reliable warning system of banking problems in the area ?What is the degree of efficiency of WAEMU banks ? Each raised question consist an essay in the thesis.First, the z-score of ROY (1952) is used as an indicator of the risk of bank failure and the Generalized Method of Moments as estimation tool. Second, intermediation margins are taken as proxy of bank profitability. Known that each country has its own features, estimate panel data to specific individual effects is adopted. Third, a dichotomous model that distinguishes healthybanks from probably weak banks is used. To finish, the parametric approach of stochastic frontiers with translogarithmique arrangement is used to deduct the total cost function of banks and to determine the efficiency of bank scores.
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Empirical studies in money, credit and banking : the Swedish credit market in transition under the silver and gold standards 1834-1913Ögren, Anders January 2003 (has links)
The empirical results reached in this thesis contradict the traditional theoretical view of money as being exogenously introduced into an economy as a medium of exchange intended to reduce the transactions costs associated with barter. Instead money was endogenously created in the form of credit. Thus, the long run neutrality of money also is called into question. The varying quality of different kinds of money reflects the demand for them. If legal tender was of higher quality than private promissary notes, it was because the former were in greater demand. Concisely put, the market determines the value, and therefore the quality, of various kinds of money. The principal problem addressed in this thesis is how, during the expansive nineteenth century, it was possible to satisfy the ever growing need for credit and means of payment without sacrificing the fixed exchange rate. Particular attention is paid to the private note issuing banks, the so called Enskilda banks, that dominated the Swedish banking system throughout the nineteenth century. In addition to their note issuing, the Enskilda banks were characterized by unlimited owner liability. An examination of the ongoing political process from a rational choice perspective, indicates that initially the concept of note issuing Enskilda banks enjoyed wide spread support. They were considered to be a reasonable response to the problem of establishing a commercial banking system in an illiquid economy. The distribution of political and economic power in favor of the Crown and the Nobility included their control over the issuance of bank charters. The monopolistic policy they followed in this regard, however, resulted in growing hostility towards these. As a result, starting in the middle 1860's, a more liberal attitude towards the establishment of banks began to prevail. By the end of the nineteenth century, various political interest were able to engineer the revocation of the Enskilda banks’ note issuing rights. The special characteristics of the Enskilda banks, the right to issue bank notes and the unlimited liability of their owners, have caused them to be perceived as outdated, at least once Joint Stock banks were introduced. In contrast to the Enskilda banks, these were unable to issue notes but instead provided their owners with limited liability. The thesis demonstrates that, given the initial illiquidity of the Swedish economy, the Enskilda banks actually were the more efficient alternative. Indeed, the note issuing privileges of the Enskilda banks became one of the principal factors behind the development of liquid domestic capital markets. An empirical study that includes the most basic constraints faced by the nineteenth century Swedish economy, the demands of the specie standard and the general shortages of reliable means of payment and of credit, reveals that the Enskilda bank system can not, strictly speaking, be considered an example of free banking. Instead of holding specie reserves, the Enskilda banks backed their notes with central bank (Riksbank) notes. This was not because the public preferred Enskilda bank to Riksbank notes. Rather it was the result of a monetary adverse selection process; Gresham’s Law. Previously utilized, lower quality, means of payment were replaced by Enskilda bank notes. By accepting some of the discount costs, the Enskilda banks made their notes circulate at par with Riksbank notes. Thus a domestic specie exchange system was created. The note issuance of the Enskilda banks paved the way for the deposit based commercial banking system that followed, and it was essential for the monetization of the economy that occurred during the late 1860's. The long run expansion of the money supply was unrelated to growth in Riksbank reserves, specie holdings or the monetary base. Other countries operating under the specie standard also experienced monetary growth, indicating that the specie standard actually was a system of credit. Money supply, as measured in terms of Riksbank and Enskilda bank notes held by the public, eventually reflected the level of output (GDP). VAR-tests indicated that annual changes in the level of Riksbank reserves preceded changes in the money supply which, in turn, preceded changes in the level of prices, thus supporting the price quantity theory. These results are summarized in a regression model that estimates domestic price movements as a function of current changes in international prices and GDP and of lagged changes in domestic prices and the money supply. The final chapter is an empirical analysis of the support provided to the Swedish banking system during the most severe financial crises of the nineteenth century. Maintaining the specie standard was over riding goal of the Riksbank. In times of crises, this concern prevented the Bank from supporting the banking system in accord with the classical lender of last resort recipe; to inject liquidity and briefly suspend convertibility. The thesis argues that in a transitional economy, such as that of nineteenth century Sweden, the fixed exchange rate makes it impossible in times of crisis to support the banks at all costs. Doing so might well convert a banking crisis into a currency crisis. Indeed, this is exactly what has happened in various countries on several occasions during the late twentieth century. Instead the appropriate procedure for acting as lender of last resort in a transitional economy is to initially support the banks, but only as long as central bank reserves are not exhausted. Should the seriousness of the crisis make this insufficient, the authorities should then proceed to import high powered money as a way of supplementing their reserves. The possibility that such action will be needed makes it particularly important that the country’s public finances be kept in good order. / <p>Diss. Stockholm : Handelshögskolan, 2003. Sammanfattning på engelska</p>
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Adaptive Reliability Analysis of Reinforced Concrete Bridges Using Nondestructive TestingHuang, Qindan 2010 May 1900 (has links)
There has been increasing interest in evaluating the performance of existing
reinforced concrete (RC) bridges just after natural disasters or man-made events
especially when the defects are invisible, or in quantifying the improvement after
rehabilitations. In order to obtain an accurate assessment of the reliability of a RC
bridge, it is critical to incorporate information about its current structural properties,
which reflects the possible aging and deterioration. This dissertation proposes to
develop an adaptive reliability analysis of RC bridges incorporating the damage
detection information obtained from nondestructive testing (NDT).
In this study, seismic fragility is used to describe the reliability of a structure
withstanding future seismic demand. It is defined as the conditional probability that a
seismic demand quantity attains or exceeds a specified capacity level for given values of
earthquake intensity. The dissertation first develops a probabilistic capacity model for
RC columns and the capacity model can be used when the flexural stiffness decays nonuniformly
over a column height. Then, a general methodology to construct probabilistic seismic demand models for RC highway bridges with one single-column bent is
presented. Next, a combination of global and local NDT methods is proposed to identify
in-place structural properties. The global NDT uses the dynamic responses of a structure
to assess its global/equivalent structural properties and detect potential damage locations.
The local NDT uses local measurements to identify the local characteristics of the
structure. Measurement and modeling errors are considered in the application of the
NDT methods and the analysis of the NDT data. Then, the information obtained from
NDT is used in the probabilistic capacity and demand models to estimate the seismic
fragility of the bridge. As an illustration, the proposed probabilistic framework is
applied to a reinforced concrete bridge with a one-column bent. The result of the
illustration shows that the proposed framework can successfully provide the up-to-date
structural properties and accurate fragility estimates.
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SAGGI IN ECONOMIA FINANZIARIA E COMPLESSITA' / ESSAYS ON FINANCIAL ECONOMICS AND COMPLEXITYGURGONE, ANDREA 22 December 2017 (has links)
L'obiettivo della tesi è lo sviluppo e nell'analisi di un modello macro-finanziario con aspetti reali e finanziari dell'economia, nell'ottica di ottenere un quadro comprensivo per l'analisi del rischio sistemico e delle instabilità.
Il primo capitolo verte sulla costruzione di un modello ad agenti che si caratterizza per la presenza del mercato dei beni, del credito, del lavoro e interbancario.
Il modello riproduce fluttuazioni endogene ed è in grado di replicare alcuni fatti stilizzati riguardanti i cicli economici e creditizi, mentre il mercato interbancario ha un ruolo importante dal punto di
vista della stabilità e dell'efficienza.
In particolare la regolazione prudenziale combinata con le aspettative adattive può esacerbare il comportamento precauzionale delle banche durante una recessione, inducendo a trattenere liquidità anche le banche solide. Inoltre la connettività del mercato interbancario ha un duplice effetto: da un lato favorisce l'accesso al credito nell'economia reale, dall'altro accresce l'accumulo di liquidità.
Il secondo capitolo si concentra su un insieme di esperimenti condotti tramite il modello precedentemente sviluppato.
Lo scopo è di confrontare tra loro politiche macro-prudenziali in cui le banche sono soggette a requisiti minimi di capitale derivati da misure di rischio sistemico.
Nello specifico gli indicatori di rischio sistemico sono suddivisi in misure di mercato e di rete. Ogni categoria è ulteriormente scomposta in misure di vulnerabilità e misure di impatto.
I risultati rivelano che le politiche costruite su indicatori di vulnerabilità sono migliori di quelle basate sull'impatto, dato che riducono i fallimenti da contagio senza peggiorare la performance macroeconomica. / The purpose of the thesis is to develop and analyse a macro-financial
model with real and financial aspects of the economy to obtain a comprehensive framework for the analysis of systemic risk and instabilities.
The first chapter concerns the construction of an agent-based-model, whose characteristic is the presence of goods, credit, labour and interbank markets.
The model reproduces endogenous business cycles and it is able to replicate some stylized facts about business and credit cycles, while the interbank market has an important role for stability and efficiency. In particular prudential regulation, combined with adaptive expectations can exacerbate the precautionary behaviour of banks during a recession, inducing liquidity hoarding by sound banks.
Furthermore connectivity of the interbank market has a twofold effect: on one side it supports credit to the real economy, on the other it increases liquidity hoarding.
The second chapter is focused on a set of policy experiments performed performed on the model previously developed. The aim is to compare different macroprudential policies where banks are subject to minimum capital requirements derived from systemic risk measures.
In detail systemic risk indicators are divided in market-based and network based measures. Each class is further decomposed in measures of vulnerability and measures of impact.
The results reveal that policies based on vulnerability indicators perform better than those based on impact, reducing contagious defaults without worsening the macroeconomic performance.
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A dívida líquida do setor público no Brasil pós-real : uma interpretação keynesianaTerra, Fábio Henrique Bittes January 2011 (has links)
A dívida líquida do setor público apresentou um notável crescimento no Brasil desde 1995, quando a estabilização monetária na era do Real passou a ser uma realidade. Quais foram os condicionantes da dinâmica do endividamento público no Brasil pós-Real? Responder essa questão é o objetivo deste trabalho. Norteará o alcance deste objetivo a hipótese de que o crescente endividamento deveu-se aos excessivos gastos financeiros incorridos pelo setor público brasileiro em função do modo de condução da política monetária, tanto no período em que o regime monetário era a âncora cambial (de julho de 1994 a janeiro de 1999) quanto após a instituição do Regime de Metas para a Inflação (julho de 1999 em diante). Para interpretarem-se as contas públicas brasileiras e conceberem-se os gastos financeiros como causadores do crescente endividamento público, este trabalho terá como referencial a teoria de John Maynard Keynes, desde sua concepção das economias monetárias de produção enquanto unidades orgânicas até as suas prescrições de política econômica. Não obstante, o norte teórico será complementado pelos autores da perspectiva pós-keynesiana. Nesse particular, destaque será conferido à Hyman Minsky e sua Hipótese de Fragilidade Financeira, a partir da qual se desenvolve o Índice de Fragilidade Financeira do Setor Público Brasileiro, que será aplicado para se aferir a posição ocupada pelas finanças públicas brasileiras entre 1995 e 2009. As conclusões do trabalho apontam para a necessidade de se instituir um novo padrão de operacionalização das políticas econômicas em que, por um lado, a política monetária seja conduzida de um modo tal que leve à redução dos gastos financeiros, e, por outro lado, que os gastos públicos em investimentos sejam elevados, a bem das criações tanto de um orçamento público equilibrado de forma intertemporal quanto, e principalmente, de um ambiente institucional propício ao investimento privado, fundamental à geração de emprego, renda e riqueza novas. / The public sector’s net debt in Brazil has showed a remarkable growth in Brazil since 1995, immediately after the period in which the monetary stability, based on Real, became a reality. What are the determinants of the public debt’s during the Brazilian Real era? Providing an answer for this question is the main objective of this thesis. In order to achieve this goal, we formulate the hypothesis that increasing public debt was due to excessive financial costs incurred by the Brazilian public sector in the way of conducting monetary policy, both in the period when the monetary regime was the exchange anchor (July 1994 to January 1999) and after the institution of the Inflation Targeting Regime (since June 1999). To analyze the figures of the Brazilian public sector and to show that there is a relationship between the financial costs and the growing of public debt we will explore the theory of John Maynard Keynes, more specifically, his conception related to the monetary economies of production as an organic system and his economic policies prescriptions. Moreover, our theoretical framework will also explore the arguments and theories of some post-Keynesian economists, in particular Hyman Minsky and his Financial Fragility Hypothesis (FFH). The Minsky`s FFH is adapted to the Brazilian public sector and, as a result, it is elaborated a Financial Fragility Index for the Brazilian Public Sector. This Index measures the Brazilian sector public performance between 1995 and 2009. As a conclusion, on the one hand, it suggests that the monetary policy has to be operated in such a way that leads to a reduction in financial expenses of the Brazilian public sector. On the other hand, the economic policy, especially fiscal policy, must be implemented to create a favorable institutional environment to the private investment, which it is essential to expand the levels of employment, income and wealth, and balance, intertemporaly, the public budget.
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Italian entrepreneurs of the construction business in a time of economic recession : ideas, strategies and movementsSischarenco, Elena January 2017 (has links)
This thesis is based on an ethnographic study of entrepreneurs of the construction business in Lombardy, Northern Italy. The aim is to gain some understanding of this business, of entrepreneurialism, and of individuals in a non-stereotypical light through a full and complex account of their daily lives. The aim is to reveal the thoughts, actions and strategies of particular local actors in their everyday contingency and contradictoriness. No attempt is made to simplify the complexity of their understandings and practices for the sake of producing a single encompassing and consistent image. Many similarities were found between the practices of entrepreneurialism and those of the discipline of anthropology. Knowledge and information are constantly sought after but are recognised as emerging in unexpected places and times and as being socially negotiated. Apprenticeship is often used as a methodology, and learning often happens through experience. Contextual application of knowledge is seen as essential. In order to exchange information and knowledge, to collaborate with other businessmen or to simply get a job, trust is fundamental and constantly negotiated. Personal relationships and trust become particularly important in an uncertain market situation, as ways to face risk. Trust is acquired slowly and accorded contextually, through face-to-face interaction and cultivated relationships, but also through positive recommendations or simply a feeling of sympathy. Knowledge, apprenticeship, trust and risk are key themes of the thesis. The blurred borders between the distinct individual personalities of my informants and their collective identities and commonalities are also discussed. The personality of an entrepreneur is seen as ideally complex, in which many (possibly contradictory) characteristics can be expected to be present, but also ideally balanced, each manifesting itself in specific situations. The ethnography also explores the fragility of the entrepreneur, in apparent contradiction to their strong and charismatic personalities. It is seen to be despite and because of their positions of power that they also feel vulnerable: their discourse is imbued with their fears for their businesses in a difficult period of economic crisis. Finally, through a ubiquitous desire to control markets and the future, we also encounter forms of corruption; corruption that is often condemned verbally but nevertheless is present in the business world and amplified by public and media discourses. The mechanisms by which work that is put out to tender is subject to possible manipulation are examined, and the ideas of the entrepreneurs about these practices are described—again demonstrating how thoughts and practices are often self-contradictory in their contextual relevance and application.
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Disgnóstico ambiental do setor noroeste do sítio urbano de Piracicaba (SP): uma abordagem geográficaSilveira, Alan [UNESP] 01 October 2009 (has links) (PDF)
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silveira_a_me_rcla.pdf: 2707026 bytes, checksum: 73ca0833e135ac48c8f366d2302015cf (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Esta pesquisa tem como objetivo fornecer um diagnóstico ambiental detalhado, de abordagem geográfica integrada, que venha a subsidiar ações de planejamento territorial do eixo de expansão urbana noroeste do sítio urbano de Piracicaba (SP). Fundamentada na Teoria Geral dos Sistemas, aplicou-se para a área de estudo a proposição metodológica de Ross (1990, 1994 e 2001), quanto à análise empírica da fragilidade de ambientes naturais e antropizados, assim como a proposta metodológica de Moroz, Canil e Ross (1994), na análise das condições de impactos ambientais derivados do uso e ocupação antrópica e das transgressões à legislação ambiental. Tais proposições metodológicas promoveram a elaboração de produtos cartográficos de síntese para análise integrada da informação geográfica, por meio da elaboração prévia de documentos cartográficos intermediários. Com base nos documentos cartográficos formulados, pretendeu-se apontar as condições impactantes impostas as formas de relevo, suas suscetibilidades aos processos morfodinâmicos, as transgressões relativas à legislação ambiental, como também apontar as áreas com restrições à expansão do sítio urbano do setor noroeste de Piracicaba, tanto do ponto de vista da fragilidade potencial, quanto do ponto de vista legal. Pôde-se constatar que as ações promovidas pelo sistema antrópico vêm alterando os fluxos de matéria e energia do sistema geomorfológico, sendo as principais formas de interferências associadas à monocultura canavieira e à expansão urbana sem planejamento. / This research aims to supply a detailed environmental diagnosis, considering an integrated geographical approach, which subsidizes territorial planning actions in the northwest urban expansion axis of Piracicaba (SP) urbane siege. It was based on the General System Theory and, for the studied area, it was applied a Ross' methodological proposition (1990, 1994 e 2001), concerning the empirical analysis of natural and anthropized environmental fragility, as well as the Moroz, Canil and Ross‟ methodological proposal (1994) for the analysis of the conditions of environmental impacts derived from the anthropical use and occupation and the transgressions to the environmental legislation. These methodological propositions furthered the elaboration of synthesis cartographic products for the geographical information integrated analysis by the previous elaboration of intermediate cartographic documents. We intended to point, from the formulated cartographic documents, the impressive conditions imposed to the relief, its susceptibilities to the morphodynamic processes, the transgressions related to the environmental legislation, as well as the areas with restrictions to expansion of the Piracicaba (SP) northwestern sector urbane siege, as the potential fragility point of view, as the legal one. We could verify that the actions promoted by the anthropical system are modifying the matter and energy flows of the geomorphological system and that the main interference forms are associated to sugar cane monoculture and the no-planning urban expansion.
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Análise ambiental integrada do componente solo como subsídio para avaliação da sustentabilidade da Bacia Hidrográfica do Rio Tenente Amaral em Jaciara Mato Grosso - Brasil.Santos, Vanderley Severino dos 06 July 2007 (has links)
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Previous issue date: 2007-07-06 / This work has as objective to to apply and compare five different methodologies of
environmental analysis and to produce maps thematic that: they characterize the environment,
they evaluate the susceptibility and the potential to the laminate erosion, they to determine
potential the environmental fragility and emergent, they evaluate the vulnerability to the erosion,
esteem the average losses of soil and the production of sediments and thus they evaluate the
environmental sustainable of the Water-Basin of the River Tenente Amaral in Jaciara, Mato-
Grosso, Brazil. For the present study one uses of techniques of Geoprocessing and cartographic
data soil, geology, the geomorphology, the climate, the vegetation and the use of the soil of the
region of the Basin, converting them for the digital format. The results demonstrated that the
studied area presents high percentage of human activities (84%) predominating the sugarcane
cultivation. The soil predominance of type LATOSSOLOS and NEOSSOLOS
QUARTZARÊNICOS in soft relief was distinguished in the region proceeding from the claysand
layer unconsolidated sediments of the Cochoeirinha Formation that if presents with bigger
area of occurrence in the place. With the application of the methodologies for the study of the
area it was verified that approximately 55% of it present average the high potential' to the
laminate erosion; natural conditions of strong instability `the very strong one'; balance in the
occurrence of processes of morphogenese and pedogenese; average losses of high soil had been
classified enter `and very high' e, in relation to the production of sediments, was verified that the
esteem production more is accented in the places where the use of the soil is intensive, being able
to reach up to 0,433 t.ha¹. / Este trabalho tem como objetivos aplicar e comparar cinco diferentes metodologias de análise
ambiental e produzir cartas temáticas que: caracterizem o meio físico, avaliem a suscetibilidade e
o potencial à erosão laminar, determinem a fragilidade ambiental potencial e emergente, avaliem
a vulnerabilidade à erosão, estimem as perdas médias de solo e a produção de sedimentos e assim
avaliar a sustentabilidade ambiental da Bacia Hidrográfica do Rio Tenente Amaral em Jaciara,
Mato-Grosso, Brasil. Para o presente estudo utilizou-se técnicas de geoprocessamento e dados
cartográficos sobre os solos, a geologia, a geomormologia, o clima, a vegetação e o uso do solo
da Bacia, convertidos para o formato digital. Os resultados demonstraram que a área estudada
apresenta elevado percentual de atividades humanas (84%) predominando o cultivo de cana-deaçúcar.
Destacou-se na região o predomínio de solos do tipo LATOSSOLOS e NEOSSOLOS
QUARTZARÊNICOS em relevo suave provenientes dos sedimentos inconsolidados arenoargilosos
da Formação Cochoeirinha que se apresenta com maior área de ocorrência no local.
Com a aplicação das metodologias para o estudo da área verificou-se que aproximadamente 55 %
delas apresentam médio a alto potencial à erosão laminar; condições naturais de instabilidade
forte a muito forte ; equilíbrio na ocorrência de processos de morfogênese e de pedogênese;
perdas médias de solos entre altas e muito altas e, em relação à produção de sedimentos,
verificou-se que a produção estimada é mais acentuada nos locais onde o uso do solo é intensivo,
podendo atingir até 0,433 t.ha1.
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