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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.
151

FORAMINÍFEROS DE MANGUEZAIS ASSOCIADOS AO ESTUÁRIO DO RIO MAPARI, MUNICÍPIO DE HUMBERTO DE CAMPOS (MA): BASES ECOLÓGICAS PARA A SUSTENTABILIDADE AMBIENTAL. / FORAMINIFERA OF MANGROVE ASSOCIATED WITH THE RIVER ESTUARY MAPARI, MUNICIPALITY OF HUMBERTO DE CAMPOS (MA): ecological bases for environmental sustaninability

Funo, Rogério Hideki Ferreira 28 November 2008 (has links)
Made available in DSpace on 2016-08-19T18:20:38Z (GMT). No. of bitstreams: 1 ROGERIO HIDEKI FERREIRA FUNO.pdf: 30693055 bytes, checksum: af16bccd626d7723e5f5c13341ebd1d7 (MD5) Previous issue date: 2008-11-28 / Intertidal foraminifera are widely recognized as efficient tools for reconstructing Holocene sea-level changes. They are also used to detect water circulation patterns and to diagnose the physical and chemical characteristics of estuarine water, revealing the steady state of the ecosystem. In this work, surface sediment samples were collected to study recent foraminiferal assemblages in an estuarine portion of the Mapari river basin, Humberto de Campos (MA), Brazil, in two ways: (1) sixteen samples collected landwards along a mangrove transect in the Gato Island, near the mouth of the Mapari river, in the Tubarão Bay, from the tidal muddy flat to the hyperhaline bare flat ( apicum ); (2) nineteen samples collected upstreamwards along the Mapari river, from the Gato Island to the Rampa settlement, where salinity is zero. In the Gato Island transect, salinity and pH were measured and the subaerial exposure time (TES) was calculated for each point. Height and DBH were also measured for the main arboreous individuals. The salinity varied from euhaline to hyperhaline (maximum of 56 ), and demonstrated no relation to TES. It was observed the dominance of Rotaliina suborder almost all along the transect, which means that a vertical zonation of foraminiferal assemblages was not found. However, eight of the sixteen points were collected surrounding a meanderin tidal creek that follows the transect. Considering just these eight points, there is a zonation in two compartments: a lower compartment that groups six samples (TES varying from 36,46% to 58,51%), dominated by Elphidium gunteri, and an upper compartment that groups two samples (TES varying from 61,95% to 75,27%), dominated by Arenoparrela mexicana. In the Mapari river, salinity and pH were measured in surface and bottom water column, and the floristic composition of the channel margins was verified, with special attention to the species of Rhizophora genus. These species have a distribution related to the salinity gradient, that varied from freshwater to euhaline. Four ecofacies were defined: (1) ecofacies 1, that groups the six closest samples to the Tubarão Bay, with polyhaline-euhaline salinity, high diversity index (H ranging from 1,44 to 2,23 and D ranging from 0,48 a 0,69), with dominance of Elphidium gunteri and Nonion sp., significant presence of Ammonia tepida, Quinqueloculina seminulum and Arenoparrela mexicana, and almost exclusive dominance of Rhizophora mangle; (2) ecofacies 2, that groups the next five samples upstreamwards, with mesohaline-polyhaline salinity, dominance of Nonion sp. and E. gunteri, and coexistence of R. mangle, R. harrisonii and R. racemosa; (3) ecofacies 3, that groups five samples with salinity varying from freshwater to mesohaline, wide dominance of Miliammina fusca, with mangrove fringe dominated by R. harrisonii and R. racemosa; (4) ecofacies 4, that groups the three upstream samples, in freshwater environment, where foraminifera are virtually absent. The results corroborate that foraminiferal assemblages can be used as an efficient tool for recognizing the steady state of the complex estuarine environment, where abiotic parameters are highly variable. / Foraminíferos da zona entre-marés são amplamente reconhecidos como eficientes ferramentas para a reconstrução de variações do nível relativo do mar no Holoceno. São também usados para detectar padrões de circulação e diagnosticar as características físicas e químicas das massas d água em ambiente estuarino, revelando as condições dominantes desse ecossistema. Neste trabalho, foram coletadas amostras de sedimento superficial para estudo das associações de foraminíferos recentes, em uma porção estuarina da bacia do rio Mapari, município de Humberto de Campos (MA), Brasil, de duas formas: (1) dezesseis amostras coletadas ao longo de um perfil transversal a um manguezal na Ilha do Gato, próximo ao encontro do rio Mapari com a Baía de Tubarão, partindo da planície lamosa ao apicum; (2) dezenove amostras ao longo do rio Mapari, partindo da Ilha do Gato, com salinidade euhalina, até o povoado Rampa, onde a salinidade é zero. No perfil Ilha do Gato, foram feitas medições de salinidade e pH, e foi calculado o tempo de exposição subaérea (TES) em cada ponto, além de medições de altura e DAP dos principais indivíduos arbóreos. A salinidade varia variou de euhalina a hiperhalina (máximo de 56 ), e não demonstrou nenhuma relação com o TES. Foi observado o domínio da subordem Rotaliina em quase todo o perfil, de forma que não foi encontrada zonação altimétrica das associações de foraminíferos. Oito dos dezesseis pontos, entretanto, foram coletados na borda de um pequeno canal de maré que acompanha o perfil, sendo que, considerando apenas eles, há uma zonação em dois compartimentos, sendo o inferior, com 6 amostras (TES variando de 36,46% a 58,51%), dominado por Elphidium gunteri, e o superior, com 2 amostras (TES variando de 61,95% a 75,27%), dominado por Arenoparrela mexicana. No rio Mapari, foram feitas medições de salinidade e pH (superficial e de fundo para ambos), e foi verificada a composição florística das margens do canal, com especial atenção para as espécies do gênero Rhizophora. Estas espécies se distribuem segundo o gradiente de salinidade, que variou do euhalino à água doce. Quatro ecofácies foram definidas: (1) ecofácies 1, agrupando as 6 amostras mais próximas da Baía de Tubarão, com salinidade polihalina-euhalina, altos índices de diversidade (H variando de 1,44 a 2,23 e D variando de 0,48 a 0,69), domínio de Elphidium gunteri e Nonion sp., presença significativa de Ammonia tepida, Quinqueloculina seminulum e Arenoparrela mexicana, e domínio quase exclusivo de Rhizophora mangle; (2) ecofácies 2, agrupando as cinco amostras da seqüência, com salinidade mesohalina-polihalina, domínio de Nonion sp. e E. gunteri, e coexistência de R. mangle, R. harrisonii and R. racemosa; (3) ecofácies 3, agrupando cinco amostras, com salinidade variando de água doce a mesohalina, amplo domínio de Miliammina fusca, e ocorrência de Rhizophora harrisonii e Rhizophora racemosa; (4) ecofácies 4, agrupando 3 amostras, em ambiente de água doce, onde foraminíferos são virtualmente ausentes. As associações de foraminíferos se mostraram uma eficiente ferramenta para reconhecimento das condições dominantes do complexo ambiente estuarino, onde os parâmetros abióticos são muito variáveis.
152

Towards a Road Safety Development Index (RSDI) : Development of an International Index to Measure Road Safety Performance

Al Haji, Ghazwan January 2005 (has links)
<p>Aim. This study suggests a set of methodologies to combine different indicators of road safety into a single index. The RSDI is a simple and quick composite index, which may become a significant measurement in comparing, ranking and determining road safety levels in different countries and regions worldwide. Design. One particular concern in designing a Road Safety Development Index (RSDI) is to come up with a comprehensive set of exposure and risk indicators which includes as far as possible the main parameters in road safety related to human-vehicle-road and country patterns instead of considering few and isolated indicators such as accident rates. The RSDI gives a broad picture compared to the traditional models in road safety.</p><p> Challenges. The differences in definitions, non-collection of data, no reliability of data and underreporting are problems for the construction of RSDI. In addition, the index should be as relevant as possible for different countries of the world, especially in developing countries.</p><p>Empirical study. This study empirically compares the road safety situation and trends between ten Southeast Asian countries and Sweden for the period 1994- 2003. Methodologies. Eleven indicators are chosen in RSDI, which have been categorised in nine dimensions. Four main approaches (objective and subjective) are used to calculate RSDI and determine which one is the best. One approach uses equal weights for all indicators and countries, whereas the other approaches give different weights depending on the importance of indicators.</p><p>Findings. The thesis examines the RSDI for the ten ASEAN countries and Sweden in 2003. The results from this study indicate a remarkable difference between ASEAN countries even at the same level of motorisation. Singapore and Brunei seem to have the best RSDI record among the ASEAN countries according to the indicators used, while Laos, Cambodia and Vietnam show lower RSDI records. Conclusions. The RSDI results seem very promising and worth testing further applications with bigger samples of countries and from different parts of the world.</p> / ISRN/Report code: LiU-Tek-Lic 2005:29
153

Quels sont les facteurs organisationnels contributifs au maintien en emploi des personnes ayant des problèmes de santé mentale dans les milieux adaptés ?

Verreault, Christine January 2008 (has links)
Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal
154

Mathematical and historical dynamics of modern economy : an application to the Korean economy / Dynamique mathématique et dynamique historique de l'économie moderne : une application à l'économie sud-coréenne

Kim, Deokmin 06 December 2017 (has links)
Il est essentiel d’étudier la dynamique non linéaire en mathématiques et nous permet d’interpréter des phénomènes aussi irréguliers et imprévisibles à la suite de processus déterministes, et non de simples erreurs ou chances statistiques.La dynamique du système est une méthodologie ainsi qu’une méthode pour implémenter des mouvements dynamiques non linéaires. Par ces deux méthodes,nous capturons la crise dans les cycles économiques et testons l’accumulation de capital, et les changements techniques dans le cadre du modèle Macro Stock Management et les appliquons à ceux de l’économie sud-coréenne. Divers outils d’analyse des séries chronologiques sont utilisés pour estimer les effets de l’investissement sur les taux de profit et les effets de l’inégalité salariale et de la dette des consommateurs sur la demande intérieure depuis la crise financière mondiale de 2008. Le Structural Vector Auto-Regressive model impose des restrictions à long terme ou à court terme sur le système VAR, il utilise pour distinguer deux variables avec des caractéristiques similaires. Perron (1989) fait valoir que les tests de racine unitaire traditionnels tels que le test Augmenté Dickey-Fuller sont susceptibles de ne pas détecter la stationnarité ou la non stationnarité des données si elles ont des ruptures structurelles. Zivot et Andrews(1992) et Lumsdaine et Papell (1997) proposent le modèle de test racine unitaire avec ruptures structurelles endogènes. Le test Gregory-Hansen fournit des informations sur une rupture structurelle dans un test de co-intégration. Le modèle ARDL (Auto Regressive Distributed Lags) est utilisé pour capturer les relations à long terme entre les variables. / It is essential to study nonlinear dynamics in mathematics, and it gives us room to interpret such irregular and unpredictable phenomena as a result of deterministic processes, not mere statistical errors or chances. System dynamics is a methodology as well as a method to implement nonlinear dynamic movements.By these two methods, we capture the crisis in the business cycles and test capital accumulation, and technical changes within the framework of the Macro Stock Management model and apply them to those of the Korean economy. In the latter part of this study, various time series analysis tools are used to estimate the effects of investment on the rates of profit and the effects of wage inequality and consumers’ debt on domestic demand since the global financial crisis of2008. Because the Structural Vector Auto-Regressive (SVAR) model impose on the long run or short run restrictions on the VAR system, it uses to distinguish two variables with similar characteristics, such as the after-tax rate of profit and the rate of profit after payment of interests and dividends excluding taxes (the after-payment rate of profit). Perron (1989) argues that the traditional unit root tests such as the Augmented Dickey-Fuller test are likely to fail to detect the stationarity or non-stationarity of the data if it has structural breaks. Zivot and Andrews (1992) and Lumsdaine and Papell (1997) propose the unit root test of the time series data with a single or two breaks in the time series. The Gregory-Hansen test provides information about a structural break in a cointegration test. The Auto Regressive Distributed Lags (ARDL) model is used to capture long-run relationships between variables.
155

A robust statistical method for determining material properties and indentation size effect using instrumented indentation testing / Une méthode statistique robuste pour déterminer les propriétés des matériaux et de l'effet de taille d'indentation en utilisant le test d'indentation instrumentée

Xia, Yang 18 September 2014 (has links)
L'indentation instrumentée est un outil pratique et puissant pour sonder les propriétés mécaniques des matériaux à petite échelle. Cependant, plusieurs erreurs (rugosité de surface, effet de taille d’indentation, la détermination de premier point de contact, etc.) affectent l'essai d’indentation instrumentée (e.g. non reproductibilité de la courbe d’indentation) et conduisent à des imprécisions dans la détermination des propriétés mécaniques des matériaux analysés. Une approche originale est développée dans cette thèse pour la caractérisation précise des propriétés mécaniques des matériaux. Cette approche fondée sur une analyse statistique des courbes d’indentation avec la prise en compte d’erreur dans la détermination du premier point de contact et des effets de la rugosité de surface. L’approche est basée sur une minimisation de la distance (défini comme l'erreur de la profondeur de contact initiale) entre l’ensemble des courbes expérimentales et celles simulées par le modèle de Bernhard de manière à générer une courbe maitresse « unique » représentative du faisceau de courbes expérimentales. La méthode proposée permet de calculer à partir de cette courbe maitresse la macro-dureté et le module d’Young du matériau en tenant compte des erreurs dues à la rugosité de surface et à l'effet de taille en indentation pour les faibles profondeurs de pénétration. La robustesse de la méthode est prouvée par son application à différents groupes d’échantillons, i.e. panels de matériaux à propriétés mécaniques diverses, différents traitements de surface (polissage, sablage) et différentes pointes d’indentation permettant de générer différents états de contraintes locaux. Une liaison quantitative entre la rugosité de surface et l'écart type de l'erreur de la profondeur de contact initiale est établie grâce à une analyse multi- échelle de la rugosité de la surface. La méthode proposée permet de caractériser les propriétés mécaniques des matériaux sans avoir recours à la préparation de surface pouvant potentiellement altérer ses propriétés (e.g. génération de contraintes résiduelles, contamination de surface…). / Instrumented indentation is a practical and powerful tool for probing the mechanical properties of materials at small scales. However, several errors (surface roughness, indentation size effect, determination of first contact point, etc…) affect the instrumented indentation testing (e.g. the low reproducibility of the indentation curves) and lead to inaccuracies in the determination of mechanical properties of materials analyzed. An original approach is developed in this thesis for the accurate characterization of the mechanical properties of materials. This approach is established by a statistical analysis of the indentation curves with taking account of error in determining the first contact point and effects of the surface roughness. This approach is basing on a minimization of the distance (defined as the initial contact depth error) between the experimental indentation curves and the ones simulated with Bernhard’s model in order to generate a “unique” representative curve which enables to represent all the experimental curves. The proposed method permits to calculate the macro-hardness and the Young’s modulus of materials from this representative curve with the consideration of the errors due to the surface roughness and the indentation size effect for shallow penetration. The robustness of the method is proved by its application to different groups of specimens, i.e. different materials with various mechanical properties, different surface preparation methods (polishing, sandblasting) and different indenter tips to generate different states of local stresses. A quantitative link between the surface roughness and the standard deviation of initial contact depth error is established by a multi-scale surface roughness analyzing. The proposed method enables to characterize the mechanical properties of materials without resorting to the surface preparation which may potentially alter its properties (e.g. generation of residual stresses, surface contamination ...).
156

Temporal Task and Motion Plans: Planning and Plan Repair : Repairing Temporal Task and Motion Plans Using Replanning with Temporal Macro Operators / Temporal uppgifts- och rutt-planering och planreparation

Hansson, Erik January 2018 (has links)
This thesis presents an extension to the Temporal Fast Downward planning system that integrates motion planning in it and algorithms for generating two types of temporal macro operators expressible in PDDL2.1. The extension to the Temporal Fast Downward planning system includes, in addition to the integration of motion planning itself, an extension to the context-enhanced additive heuristic that uses information from the motion planning part to improve the heuristic estimate. The temporal macro operators expressible in PDDL2.1 are, to the author's knowledge, an area that is not studied within the context of plan repair before. Two types of temporal macro operators are presented along with algorithms for automatically constructing and using them when solving plan repair problems by replanning. Both the heuristic extension and the temporal macro operators were evaluated in the context of simulated unmanned aerial vehicles autonomously executing reconnaissance missions to identify targets and avoiding threats in unexplored areas. The heuristic extension was proved to be very helpful in the scenario. Unfortunately, the evaluation of the temporal macro operators indicated that the cost of introducing them is higher than the gain of using them for the scenario.
157

Etude des interactions hydrodynamiques et colmatage dans des milieux très perméables / Hydrodynamic interactions and clogging study in highly permeable porous media

Jouini, Manel 09 April 2018 (has links)
La Société le Nickel ’SLN’ est l’un des plus grands exploitants de nickel en Nouvelle Calédonie. Le Stockage des déchets de l’exploitation minière sur le site d’exploitation se fait sous forme de tas manufacturés appelés versants. Pour assurer la stabilité de ces versants, il est nécessaire d’assurer un stockage hors d’eau de ces stériles miniers. Pour se faire, une mise en place des ouvrages en enrochement enterrés se fait au fur et à mesure de l’avancement des travaux d’installation des versants. Le rôle de ces ouvrages enterrés est de maintenir l’écoulement d’eau à travers le milieu poreux. Le premier objectif de la thèse est donc de mieux comprendre les interactions hydrodynamiques dans les milieux très perméables dans le cas d’écoulements pleinement turbulents. La première partie de ce travail concerne une étude expérimentale menée à l’Institut National Agronomique de Tunisie (INAT) mais aussi à l’Institut de mécanique de fluide de Toulouse (IMFT) dont le but est d’étudier à la fois l’évolution de la ligne d’eau dans les milieux macroporeux et la variation de la perméabilité de ces derniers en fonction du nombre de Reynolds. Des simulations avec des modèles de perte de charge les plus utilisés dans la littérature ont été effectuées, pour tester leur capacité à reproduire la ligne d’eau dans les conditions de nos expériences. Les deux relations de Forchheimer (1901) et d’Ergun (1952) donnent des résultats proches de nos expériences avec des valeurs de coefficients adaptés pour notre cas, alors que la relation de Barree et Conway (2004) ne semble pas reproduire les résultats attendus. L’eau qui circule dans les ouvrages enterrés est une eau chargée d’où l’intérêt d’étudier le transport sédimentaire dans ces milieux macroporeux. Pour se faire, une étude expérimentale a été réalisée sur le transport et le dépôt des particules dans des milieux synthétiques constitués de particules de diamètre moyen de 15 cm / The 'SLN' Company is one of the largest nickel operators in New Caledonia. The mining wastestorage at the operation site is as a slope. To ensure the stability of these slopes, it is necessary toensure an out of water storage of the waste rock. To do that, an underground rockfillimplementation is installed. The purpose of these buried structures is to maintain the flow of waterthrough its pores. The first objective of the thesis is to better understand the hydrodynamicinteractions in highly permeable porous media and in case of fully turbulent flows. The first part ofthis work relates to an experimental study carried out at the National Agronomic Institute of Tunisia(INAT) and the Institute of Fluid Mechanics of Toulouse (IMFT) whose aim is to study the waterprofile evolution in macro porous media and the permeability variation as a function of theReynolds number. Simulations with the most widely used pressure drop relationships in theliterature were performed to check their ability to reproduce our experimental water profile. Thetwo relations of Forchheimer (1901) and Ergun (1952) give the most satisfactory results withadapted coefficients values for our case, whereas the Barree and Conway (2004) formula doesn’tseems to give expected results. Given that the circulating water in these buried structures is acharged water, we studied the sedimentary transport in macro porous media. To do this, anexperimental study was carried out on the transport and deposition of particles in the studiedporous media which mean diameter is d=15 cm.
158

O gênero anúncio eletrônico pessoal e as escolhas de seus anunciantes: uma análise do posicionamento atitudinal de gays e heterossexuais na internet / Dating ads and the lexical choices of their advertisers: a study of the stance-taking of gays and heterosexuals

Daniel de Augustinis Silva 13 March 2007 (has links)
Este trabalho se situa na fronteira entre os estudos culturais e os estudos lingüísticos. Ele tem como objetivo observar possíveis diferenças em termos de organização de gênero e escolhas lexicais entre os anúncios pessoais feitos por gays e heterossexuais do sexo masculino. O corpus de análise consiste de quarenta anúncios retirados de dois sites de encontros da Internet, sendo que vinte são originariamente escritos por gays e os outros vinte por heterossexuais do sexo masculino. A base desta pesquisa se encontra nos trabalhos de Swales (1990) e Bhatia (1993) sobre a descrição de gêneros e no trabalho de Hoey (1997) sobre narrativas eróticas. Deste último retiramos alguns conceitos sobre a auto-descrição e a descrição do objeto de desejo. Inicialmente, os anúncios eletrônicos pessoais são comparados com anúncios pessoais impressos (cf. Shalom 1997), na tentativa de verificar como os anúncios impressos podem ter se adaptado ao meio digital. Num segundo momento, a análise se concentra na aplicação do sistema de Avaliação (ou Appraisal) de Martin e White (2005) a fim de caracterizarmos como os gays e heterossexuais do sexo masculino avaliam a si próprios e a seus objetos de desejo. A dissertação sugere que há diferenças relacionadas ao posicionamento atitudinal dos gays e heterossexuais, especialmente em relação à utilização de Afeto. Observam-se diferenças também não previstas por nossas perguntas de pesquisa, que não podem ser atribuídas nem às organizações diferentes dos sites, nem às escolhas lexicais dos anunciantes, mas sim aos tipos de sites e audiências escolhidos pelos anunciantes / The present work lies on the borderline of cultural and linguistic studies. It aims at examining whether there are differences concerning genre organization and lexical choices in ads filled in by gay and heterosexual males. The corpus consists of forty ads from two dating sites on the internet: twenty are originally written by gay males and the other twenty are written by heterosexual males. This research draws on works such as Swales (1990) and Bhatias (1993) on genre description and on Hoeys (1997) on erotic narratives. From the latter we have borrowed a few key concepts to help us analyze self and other description. At an early stage, the internet ads are compared to printed ads (cf. Shalom 1997) in an attempt to check how these ads should have adapted to the digital medium. Afterwards, we resort to Martin and Whites (2005) Appraisal system so as to characterize how gays and heterosexuals see themselves and their desired others. The dissertation suggests that there are differences related to the attitudinal positioning of gays and heterosexuals, particularly in the use of Affect. There are also findings unforeseen at the beginning of the research. In other words, these differences do not come down either to the variation in the organization of the sites, or to the lexical choices of the advertisers, but rather to the kind of site chosen by the advertisers
159

Nitrogênio, arsênio, bário e estado nutricional de plantas de milho cultivadas em latossolos tratados com lodo de esgoto

Alvarez Lazo, Ronald [UNESP] 23 July 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:33:38Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-07-23Bitstream added on 2014-06-13T20:25:28Z : No. of bitstreams: 1 alvarezlazo_r_dr_jabo.pdf: 871992 bytes, checksum: f010c0f2b021f5d9309efdc48c4d6d40 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O objetivo do trabalho foi avaliar o efeito da aplicação de doses anuais de lodo de esgoto (LE) por dez anos consecutivos, no comportamento das formas de nitrogênio em Latossolos cultivados com milho; no estado nutricional, produção de grãos e matéria seca da planta, nos teores de As e Ba no solo e nos teores de As e Ba na folha e no grão de milho. Dois experimentos foram realizados em Jaboticabal (SP), Brasil, sob condições de campo, em blocos ao acaso em Latossolo Vermelho eutroférrico (LVef) e Latossolo Vermelho distrófico (LVd). Os tratamentos foram aplicações de LE (5, 10 e 20 Mg ha-1, b.s.) e uma testemunha (sem LE e com fertilização NPK). O teor médio de N-total apresentou decréscimo com o aumento da profundidade, e aumentou por efeito das doses de LE nos dois solos. Há movimentação do N-NO3 - para as camadas inferiores do solo no LVd. O teor de N-NH4 + no LVef e LVd mostrou comportamento irregular com o incremento da profundidade, predominando sobre o N-NO3 - até a camada 0,60-0,80 m de profundidade no LVef. Dependendo do LE utilizado, tipo de solo e da dose aplicada o LE provocou incrementos no teor de B, Mg, Mo e Zn acima da faixa considerada adequada para o milho. No LVd houve diferença entre tratamentos no teor de As e Ba no solo com decréscimo da concentração com o aumento da dose de LE. Houve diferença entre tratamentos no teor de Ba extraível pelo Mehlich 3, e diminuição do teor pelo incremento da dose de LE no LVef e LVd. No LVef o teor de As no grão aumentou por efeito da dose de LE aplicada. Nos dois solos houve decréscimo do teor de Ba no grão por efeito dos tratamentos. Em LVd o teor de As e Ba foliar do T0 difere dos tratamentos com lodo de esgoto, observando-se decréscimo da concentração com o aumento da dose de LE. O As e Ba adicionados aos solos pelo lodo de esgoto não afetou a produção de grãos e matéria seca das plantas de milho / The aim of this work was to evaluate the effect of the application of annual dosages of Sewage sludge (Ss) during a period of ten years of experimentation, on soil nitrogen response, the nutritional stage, the grain and dry matter yield of maize plants, the As and Ba contents in soil, leaves and grain of maize. Two experiments were carried out in Jaboticabal-SP, Brazil, in randomized blocks under field conditions, in Typic Eutrothox (TH) and Typic Haplorthox. The treatments were, Ss applications rates (5; 10 and 20 Mg ha-1 DW) and a control (without Ss and with NPK fertilization).The average content of total N showed decrease with the rising of depth and increase with the dosages in both soils. The results showed NO3 --N moving to the lower soil layers, in TH. NO4 +-N content in TE and TH showed uneven behavior with the rising of the soil depth, prevailing over NO3 --N until depth layer of 0,60-0,80 m in TE. Depending of the Ss used, soil type and applied dosage the Ss provoked increasing of B, Mg, Mo, and Zn content over the level considered adequate for corn. There was difference between treatments in soil As content in TH, with concentration decrease by the increase of Ss dosage. Ba content determined in TH was affected by treatments showing content decrease by the Ss dosage increase. There was difference between treatments in Ba content extractable by Mehlich 3, and Ba content decrease by increasing of Ss dosage in both soils. In TE As content in corn grain increased by the effect of Ss dosages applied. In both soils decrease of Ba content was found in grain by the effect of Ss treatments. In TH foliar As and Ba content of control treatment differs from Ss treatments, observing decrease of foliar As and Ba concentration by increase of Ss dosage. As and Ba added to the TE and TH by sewage sludge rates didn’t affect dry matter and grain yield of maize plants
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Modélisations simplifiées pour l’analyse du risque sismique de bâtiments en béton armé / Simplified models for the analysis of seismic risk of reinforced concrete buildings

Hasnaoui, Fadhila 23 June 2014 (has links)
Modélisations simplifiées pour l’analyse du risque sismique de bâtiments en béton armé. Résumé de la thèse en français (1800 signes max.) : La thèse s’inscrit dans le cadre du projet MARS (Méthodes Avancées pour le Risque Sismique, EDF R&D). Elle concerne plus particulièrement certaines tâches sur le développement des méthodes simplifiées et robustes de calcul pour permettre la simulation intensive et table de la réponse sismique de bâtiments en béton armé. En effet, |’analyse de risque nécessite un très grand nombre de calculs pour tenir compte des incertitudes, tant sur le chargement (aléa sismique) que sur le comportement non linéaire des structures. Dans la première partie de ce travail, nous effectuerons une étude bibliographique sur les modèles de résolution sismique pour les bâtiments en béton armé. Cette étape va nous permettre de rassembler le maximum d’éléments nécessaires permettant de comprendre et d’identifier tous les paramètres, les avantages, les inconvénients et la limite d’utilisation de chaque procédure de calcul numérique par éléments finis. Dans la deuxième partie, on développe un macro-élément de poteau-poutre, associé â un modèle de comportement non linéaire afin de traduire la réponse de la structure sous les sollicitations sismiques. Des hypothèses cinématiques ont été adoptées pour limiter le nombre de degrés de liberté. La loi de comportement globale en cisaillement est décrite dans le cadre delà plasticité. Nous avons choisi un modèle à écrouissage cinématique pour prendre en compte la dissipation due à la fissuration. Les paramètres sont identifiés à partir de résultats expérimentaux ou bien pré-calculés par des analyses â une échelle locale (calculs 3D par éléments finis ou calcul simplifié type « Modified Compression Field Theory >>). Des analyses numériques ont été réalisées afin de valider le modèle proposé comparant à des essais expérimentaux disponibles dans la littérature. / This PhD is part of the MARS project (Advanced Methods for Seismic Risk, EDF R&D). It relates particularity to the development of simplified and robust calculation. The overall aim is to significantly reduce the intensive computation time without loosing a reliable simulation of the seismic response of reinforced concrete buildings methods. Seismic risk analysis requires a very large number of repeated calculations to account for uncertainties of both the loading (seismichazard) and the nonlinear behaviour of structures. ln the first part of this work, a bibliographic study on seismic resolution models for reinforced concrete buildings is provided. This step allows collecting the maximum of necessary elements to understand and identify all the parameters, advantages, disadvantages and limits of use of each finite element calculation method. In the second part, a macro—elements for beam—column joint associated to a nonlinear behavior to reflect the response to the structure under seismic loads ls developed. Kinematic assumptions have been adopted to limit the number of degrees of freedom. The law of global shear behavior is described in the context of plasticity. A model with kinematic hardening is chosen to account for the dissipation due to cracking. Model parameters are identified from experimental results or pre-calculated by analysis on a local scale vla 3D finite element calculation or the implied "Modihed Compression Field Theory Numerical analyses were performed to validate the proposed approach against experimental tests available in the literature.

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