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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.
401

A study of promotion and attrition of mid-grade officers in the U.S. Marine Corps: are assignments a key factor?

Morgan, Jerry R. 03 1900 (has links)
Approved for public release, distribution is unlimited / This study analyzes the relationship between selection to major in the Marine Corps, and the survival of midgrade officers to the promotion point of major, by investigating the effects of billet assignments. Specifically, this study looks at the influence of the percentage of time spent in the Fleet Marine Forces (FMF), the percentage of time spent in primary military occupation (PMOS) billet assignments, and the effect of having served in combat, recruiting, security forces, joint, and drill field duties. Models were formulated using groundwork established in previous promotion, retention, and attrition studies. Assignment variables were then introduced to the models. To account for officers' choice for continued service vice forced attrition, the sample was restricted to officers who had attained five years of service. Probit regression was used to find the influence of career assignments on the probability of selection; Heckman's correction was used to control for self-selection bias; and, Cox proportionalhazard regression was used, utilizing the same assignment factors, to find the influence of assignments on the likelihood of attrition. The findings indicated that FMF and PMOS ratios above 60 percent had a negative effect on promotion and retention. Also indicated was that time spent outside the PMOS, in "B" billets, had a positive effect on retention. In a time of budgetary constraints, this information may provide assistance to personnel planners as an alternative to pecuniary measures used to maintain and shape the force. / Major, United States Marine Corps
402

Élections expérimentales : la désertion stratégique et la participation sous différents modes de scrutin

Labbé St-Vincent, Simon 10 1900 (has links)
Cette thèse s'intéresse au lien qui existe entre le système électoral et deux comportements importants de la vie civique, soit la participation à une élection et la désertion stratégique du candidat préféré vers un autre candidat. Ces thèmes sont abordés dans de nombreux et de très importants ouvrages en science politique. En passant par la théorie (Downs, 1957) jusqu'à des études de terrain par l'entremise de sondages (Abramson, 2010; Blais, 2010), diverses méthodologies ont été employées pour mieux expliquer les choix des électeurs. Ma contribution à l'avancement des connaissances dans ce domaine passe par l'usage de la méthode expérimentale pour mieux saisir les similitudes et différences dans les comportements des électeurs sous le système uninominal à un tour (UT) et la représentation proportionnelle (RP) ainsi que les mécanismes au niveau individuel qui produisent ces similitudes et différences. Le cœur de la thèse est composé des trois articles dont voici les résumés : Article 1. Des élections expérimentales faites à Montréal, Paris et Bruxelles permettent d'estimer l’influence directe du mode de scrutin sur la décision des électeurs de voter ou non, et de voter pour leur parti préféré ou non. En tout, 16 groupes de 21 électeurs votent sous différents systèmes électoraux, soit le UT et la RP. Les préférences sont attribuées aléatoirement et connues de tous les participants. Nos résultats indiquent que le vote n'est pas globalement plus sincère et que la participation électorale n'est pas plus élevée sous le système proportionnel. Toutefois, nous observons moins de désertion d'un petit parti sous le système proportionnel. Article 2. Les expériences permettent également d'expliquer pourquoi les électeurs votent parfois pour un parti autre que leur parti préféré. La conclusion principale est que la décision de voter de façon sincère ou non est influencée par les préférences individuelles, mais aussi par les perceptions des chances de gagner des candidats ainsi que des chances que son propre vote puisse décider le résultat de l'élection. Les électeurs qui désertent leur premier choix prennent en considération quel candidat est le plus près de leurs positions politiques, mais également de la viabilité de cette alternative. De plus, les électeurs qui aiment prendre des risques ont davantage tendance à déserter. Article 3. Le modèle de l'électeur pivot est mis à l'épreuve pour mieux comprendre la décision de voter ou non lors d'une élection. Nos expériences permettent de répliquer, avec un devis expérimental différent, les résultats importants des travaux de Duffy et Tavits (2008). Nos résultats confirment que la perception d'être pivot augmente la participation, que ces perceptions sont sujettes à la surestimation et que cette surestimation ne décline pas complètement dans le temps. Nous allons également plus loin que les recherches de Duffy et Tavits et nous trouvons que la participation n'est pas plus forte sous RP que sous UT et que la probabilité d'être pivot a un impact plus important chez les électeurs évitant de prendre des risques. / This thesis focuses on the relationship between the electoral system and two important behaviors of civic life: participation in an election and the strategic desertion of the preferred candidate. These topics are addressed in very important books in political science. From theory (Duverger, 1954; Downs, 1957) to empirical research using surveys (Abramson, 2010; Blais, 2010), various methodologies have been used to better explain voter's choices. My contribution to knowledge is the use of experimental methods to better understand both similarities and differences in voter behavior under the plurality system (PLU) and the proportional representation (PR) system and the individual level mechanisms that produce these similarities and differences. The core of the thesis consists of three articles summarized below: Article 1. Experimental elections conducted in Montreal, Paris and Brussels estimate the direct influence of the voting system on the voters' decision whether to vote or not, and vote for their preferred party or another party. In all, 16 groups of 21 voters take part in elections under different electoral systems. The systems are simple plurality and proportional representation. Preferences are randomly assigned and known by all participants. Our results indicate that voting is globally not more sincere and that voter turnout is not higher under the proportional system. However, we observe less desertion of small parties under the proportional system. Article 2. We perform a laboratory experiment to explain why voters sometimes vote for a party other than the preferred one. The main conclusion of the paper is that in addition to voter preferences, perceptions of winning chances and belief in the possibility of affecting the outcome are key factors in the voter’s decision to vote sincerely or not. When they desert their first choice, voters consider their preferences and the viability of the alternatives. Voters who like to take risks are more prone to desert. Article 3. This paper examines the decision to vote or not in experimental elections. We replicate the important findings of Duffy and Tavits (2008) with a different design. Our results support their finding, that is, turnout is affected by the belief that one's vote counts and overestimation of the probability that one's vote counts does not decrease completely over time. Going beyond previous research, we also find that turnout is not higher under a proportional system than under a plurality system, and beliefs about being in a pivotal disposition have a greater impact on turnout among the risk averse.
403

Étude prospective des causes de mortalité chez l'espèce caprine avec emphase sur la lymphadénite caséeuse

Debien, Elaine 12 1900 (has links)
En Amérique du Nord, et particulièrement au Canada, il y a très peu de données sur l’incidence des causes de mortalité chez l’espèce caprine. Le premier objectif de cette étude était de déterminer les principales causes de mortalité chez les chèvres au Québec. Depuis 2006, avec l’arrêt de la vaccination contre la lymphadénite caséeuse, les éleveurs de caprins laitiers et de boucherie du Québec ont rapporté une recrudescence des abcès chez leur bétail. Le second but de cette étude était de déterminer l’importance de la lymphadénite caséeuse dans le dépérissement et la mortalité des chèvres du Québec. Cent-cinquante-deux chèvres provenant de 13 élevages différents ont été soumises pour nécropsie et la cause de mortalité, de même que la présence d’abcès (s’il y a lieu), leur localisation et leur cause furent compilés. Les mortalités proportionnelles étaient, par ordre décroissant : l’entérotoxémie de type D (n= 26; 17,1%), la pneumonie (n= 21; 13,8%), la paratuberculose (n= 16; 10,5%), listériose encéphalitique (n= 10; 6,6%), la toxémie de gestation (n= 8; 5,3%), l’arthrite-encéphalite caprine (n= 7; 4,6%) et la lymphadénite caséeuse (n= 6; 3,9%). La lymphadénite caséeuse a été diagnostiquée chez 24,3% des chèvres soumises, mais sans être une cause majeure de dépérissement ou de mortalité. Les abcès étaient internes dans 54,1% des cas. Au total, la paratuberculose a été diagnostiquée chez 29 chèvres (16 en étant décédées) et fut considérée comme une cause majeure de dépérissement, d’émaciation et de mortalité. Le développement et l’implantation de mesures préventives contre cette maladie seraient donc à envisager dans le futur. / In North America, and especially in Canada, the incidence and the causes of death in goats are not well documented. The first objective of this study was to determine the main causes of mortality in goats in Quebec. Dairy and meat goat farmers had reported an increase in abscesses in their herd since vaccination for caseous lymphadenitis stopped being available (2006) in Quebec. The second objective of this study was to determine the importance of caseous lymphadenits in wasting and mortality in caprine herds from Quebec. One hundred and fifty-two goats from 13 different herds from Quebec were submitted for necropsy and the cause of mortality, as well as the presence, location and cause of abscesses (if present) were recorded. Proportional mortalities were, in decreasing order: type D enterotoxemia (n= 26; 17,1%), pneumonia (n= 21; 13,8%), paratuberculosis (n= 16; 10,5%), encephalitic listeriosis (n= 10; 6,6%), pregnancy toxemia (n= 8; 5,3%), caprine arthritis-encephalitis (n= 7; 4,6%) and caseous lymphadenitis (n= 6; 3,9%). Caseous lymphadenitis was diagnosed in 24.3% of the submitted goats, but was not a major cause of debilitation or mortality. Abscesses were localized internally in 54.1% of the cases. Overall, paratuberculosis was diagnosed in 29 goats (16 of which died of the condition) and was considered a major cause of wasting, emaciation and mortality. Development and implementation of preventive measures to control this disease in goat herds would certainly be relevant in the future.
404

Investissement optimal et évaluation d'actifs sous certaines imperfections de marché / Optimal investment and pricing under certain market imperfections

Benedetti, Giuseppe 23 September 2013 (has links)
Dans cette thèse, nous nous intéressons à des sujets différents en mathématiques financières, tous liés aux imperfections de marché et à la technique fondamentale de la maximisation d'utilité. Elle comporte trois parties. Dans la première, qui se base sur deux papiers, nous considérons le problème d'investissement optimal sur un marché financier avec coûts de transaction proportionnels. On commence par étudier le problème d'investissement dans le cas où la fonction d'utilité est multivariée (ce qui s'adapte particulièrement bien aux marchés des devises) et l'agent a une dotation initiale aléatoire, qui peut s'interpréter comme une option ou un autre contrat dérivé. Après avoir analysé les propriétés du problème et de son dual, nous utilisons ces résultats pour examiner, dans ce contexte, certains aspects d'une technique de pricing devenue populaire dans le cadre des marchés incomplets, l'évaluation par indifférence d'utilité. Dans le deuxième chapitre, nous étudions le problème d'existence d'un ensemble de prix (appelés "prix fictifs" ou "shadow prices") qui offrirait la même utilité maximale à l'agent si le marché n'avait pas de frictions. Ces résultats sont utiles pour clarifier le lien entre la théorie classique des marchés sans frictions et la littérature en croissance rapide sur les coûts de transaction. Dans la deuxième partie de cette thèse, nous considérons le problème d'évaluation de produits dérivés par indifférence d'utilité dans des marchés incomplets, où la source d'incomplétude provient du fait que certains actifs ne peuvent pas être échangés sur le marché, ce qui est le cas par exemple dans le cadre des modèles structurels pour le prix de l'électricité. Sous certaines hypothèses, nous dérivons une caractérisation en terme d'équations différentielles stochastiques rétrogrades (EDSR) pour le prix, et nous nous concentrons ensuite sur les options européennes en établissant en particulier l'existence d'une stratégie de couverture optimale, même lorsque le payoff présente des discontinuités et est éventuellement non borné. Dans la dernière partie, nous analysons un simple problème de principal-agent à horizon fini, où le principal est essentiellement interprété comme un régulateur et l'agent comme une entreprise qui produit certaines émissions polluantes. Nous traitons séparément les problèmes du principal et de l'agent et nous utilisons la théorie des EDSR pour fournir des conditions nécessaires et suffisantes d'optimalité. Nous effectuons également des analyses de sensibilité et nous montrons des résultats numériques dans le but de fournir une meilleure compréhension du comportement des agents. / In this thesis we deal with different topics in financial mathematics, that are all related to market imperfections and to the fundamental technique of utility maximization. The work consists of three parts. In the first one, which is based on two papers, we consider the problem of optimal investment on a financial market with proportional transaction costs. We initially study the investment problem in the case where the utility function is multivariate (which is particularly suitable on currency markets) and the agent is endowed with a random claim, which can be interpreted as an option or another derivative contract. After analyzing the properties of the primal and dual problems, we apply those results to investigate, in this context, some aspects of a popular pricing technique in incomplete markets, i.e. utility indifference evaluation. In the second contribution to the transaction costs literature, we investigate the existence problem for a set of prices (called shadow prices) that would provide the same maximal utility to the agent if the market did not have frictions. These results shed some light on the link between the classical theory of frictionless markets and the quickly growing literature on transaction costs. In the second part of this thesis we consider the utility indifference pricing problem in incomplete markets, where the source of incompleteness comes from the fact that some assets in the market cannot be actively traded, which is the case for example in the framework of structural models for electricity prices. We provide a BSDE characterization for the price under mild assumptions, and then focus on the case of European claims by establishing in particular the existence of an optimal hedging strategy even when the claim presents discontinuities and is possibly unbounded. In the last contribution we analyze a simple principal-agent problem in finite time horizon, where the principal is mainly interpreted as a regulator and the agent as a firm producing some kind of polluting emissions. We separately treat both the agent's and the principal's problems and use the BSDE theory for providing necessary and sufficient conditions for optimality. We also perform some sensitivity analyses and give numerical results in order to provide a better understanding of the agents' behavior.
405

Nová teória podniku - komplexná analýza podniku / The new theory of business - a comprehensive analysis of the company

Pastorková, Ivana January 2010 (has links)
The aim of the Master's thesis is a comprehensive analysis of the company's financial health over a certain period. In the theoretical part of the work I describe the methods of analysis from basic ones to more complex assessment models. In the practical part, I apply the acquired knowledge directly to the construction company with using its accounting documents. The financial analysis consists of analysis of absolute, differential and proportional company's indexes, which are followed by comparison of the company and industry. Last part focuses on the credit-worthy and bankruptcy models of financial situation assessments as well as their final comparison. At the end, I summarizes the financial situation by using methods and propose measures to improve the future development.
406

Which population level environmental factors are associated with asthma, rhinoconjunctivitis and eczema? Review of the ecological analyses of ISAAC Phase One.

Asher, M Innes, Stewart, Alistair W, Mallol, Javier, Montefort, Stephen, Lai, Christopher K W, Aït-Khaled, Nadia, Odhiambo, Joseph, Chiarella, Pascual, The ISAAC Phase One Study Group 21 January 2010 (has links)
Revisión por pares
407

Représentation proportionnelle et participation électorale : l’hétérogénéité des populations importe-t-elle?

Saint-Martin-Audet, Grégoire 05 1900 (has links)
No description available.
408

Diagnóstico de falhas via observadores de estado com excitações desconhecidas, identificadas via funções ortogonais /

Morais, Tobias Souza. January 2006 (has links)
Orientador: Gilberto Pechoto de Melo / Banca: Amarildo Tabone Paschoalini / Banca: Valder Steffen Júnior / Resumo: Neste trabalho desenvolveram-se metodologias de diagnóstico de falhas utilizando observadores de estado do tipo Filtro de Kalman, nas quais, as entradas para os observadores são identificadas utilizando as funções ortogonais de Fourier, Legendre e Chebyshev. Um tipo de observador denominado Proporcional-Integral é apresentado para a identificação de entradas desconhecidas. Este observador consegue estimar, sob certas condições, as entradas e ou distúrbios presentes no sistema e essas entradas são utilizadas para a diagnose de falha utilizando um observador do tipo Filtro de Kalman. Também é apresentado o desenvolvimento de uma metodologia de identificação de parâmetros bem como das forças de excitação, através das funções ortogonais, utilizando somente a resposta. Apresentam-se resultados obtidos por meio de simulações computacionais e realizados experimentalmente numa bancada de teste pertencente ao laboratório de vibrações mecânicas do Departamento de Engenharia Mecânica de Ilha Solteira. / Abstract: In this work a methodology for fault diagnosis of mechanical systems was developed by using Kalman Filter state observes, in which the input of the observers are identified by using Fourier, Legendre and Chebyshev orthogonal functions. A proportional-integral observer is presented to the unknown input identification. This observer is able to find the unknown inputs of the system and these inputs are used to fault detection purposes by using a Kalman Filter Observer. The methodology for the identification of system parameters and excitation forces by using only the response of the system, through orthogonal functions. The methodology developed is applied to a mechanical structure containing vibrating tables, in the Mechanical Vibrations Laboratory, at Unesp, Ilha Solteira. / Mestre
409

Commande robuste pour une classe de systèmes non linéaires à paramètres variants : application aux projectiles guidés / Robust Control for a Class of Nonlinear Parameter-Varying Systems : Application to Guided Projectiles

Sève, Florian 05 December 2016 (has links)
Ce mémoire de thèse traite du développement des dynamiques et des lois de commande de vol d’un projectile d’artillerie gyrostabilisé guidé par une tête découplée. Un modèle non linéaire du projectile est proposé, et sert à calculer un modèle linéarisé de la dynamique de roulis du nez et un modèle q-LPV des chaînes de tangage et de lacet à paramètres fortement variants. Les incertitudes de modélisation sont prises en compte pour concevoir l’autopilote. Des propriétés importantes des projectiles gyrostabilisés, qui sont liées au couplage dynamique tangage/lacet, aux modes internes et à la stabilité, sont mises en valeur grâce au modèle q-LPV. En vue de l’utiliser pour calculer une loi de commande, la dimension de son vecteur des paramètres est réduite et la position des capteurs intégrés dans le nez est considérée. Un seul correcteur linéaire est suffisant pour la dynamique de l’angle de roulis du nez alors qu’une stratégie systématique de commande par séquencement de gains basée sur une linéarisation est élaborée séparément pour générer un correcteur séquencé des facteurs de charge de tangage et de lacet. Des structures de commande fixées d’ordre réduit sont conçues en appliquant la même approche de synthèse linéaire H∞ par façonnage de gain de boucle pour les axes de roulis et de tangage/lacet. De très bonnes propriétés de performance et de robustesse en boucle fermée, comparables à celles fournies par des correcteurs d’ordre plein, sont obtenues. Finalement, l’efficacité de l’autopilote augmenté d’une loi de guidage par navigation proportionnelle pure est vérifiée via de nombreuses simulations non linéaires de trajectoires. Ces dernières correspondent à des scénarios de vol nominaux d’interception de cibles balistiques, non balistiques immobiles, ou manœuvrantes, ainsi qu’à des scénarios considérant des perturbations sur les conditions de tir ou sur les dynamiques du projectile guidé / This thesis addresses the development of the flight dynamics and control laws for an artillery spin-stabilized projectile equipped with a decoupled guidance nose. A projectile nonlinear model is discussed, and it is used for computing a linearized model of the nose roll dynamics along with a q-LPV model of the highly parameter-varying pitch/yaw-dynamics. Modeling uncertainty is taken into account for autopilot design. Important properties specific to spin-stabilized projectiles, which are relevant to pitch/yaw-channel cross-coupling, internal modes and stability, are highlighted using the q-LPV model. In order to use the latter for calculating a control law, the dimension of its parameter vector is reduced and the position of the nose-embedded sensors is considered. A single linear controller is sufficient for the nose roll angle dynamics whereas a systematic linearization-based gain-scheduled control strategy is separately devised to provide a pitch/yaw-axis load factor gain-scheduled controller. Controllers of reduced-order fixed structures are computed by applying the same H∞ linear design loop-shaping approach for the roll and pitch/yaw-axes. Very good closed-loop performance and robustness properties, which are similar to those provided by full order controllers, are obtained. Finally, the effectiveness of the autopilot augmented by a pure proportional navigation guidance law is verified through a variety of nonlinear trajectory simulations. The latter correspond to nominal flight scenarios with ballistic, non-ballistic stationary, and maneuvering interception points, and to scenarios with perturbed launch conditions or guided projectile dynamics
410

Avaliação da radioatividade natural em águas potáveis de superfície e subterrâneas da região de Caetité,BA / Evaluation of natural radioactivity in superficial and underground drinking water, from the Caetité region, BA

Silva, Luciana Sousa 21 December 2011 (has links)
O Brasil possui a sétima maior reserva geológica de urânio do mundo, com aproximadamente 310 mil toneladas. A Província Uranífera de Lagoa Real, na região de Caetité e Lagoa Real, situado no centro sul da Bahia, é considerada a mais importante província monominerálica do Brasil. A população urbana que vive no distrito uranífero nas cidades de Caetité, Lagoa Real e Livramento de Nossa Senhora usa água potável oriunda do abastecimento público. Na área rural, caracterizada por freqüentes secas, os moradores recebem água de poços escavados e perfurados como também, de pequenas barragens e reservatórios abastecidos pelas chuvas. Este trabalho determinou os níveis de radioatividade alfa e beta total e as concentrações de urânio em diversos tipos de água consumidas pela população urbana e rural da Província Uranífera de Lagoa Real. As atividades α e β total foram determinadas com detector proporcional de fluxo gasoso e baixa radiação de fundo. As concentrações de urânio foram determinadas com o Espectrômetro de Massa com Fonte de Plasma Indutivo (ICP-MS). Os resultados obtidos foram comparados com as recomendações recentes de 2011 da Organização Mundial da Saúde, a portaria nº 2914 de 12/12/2011 do Ministério da Saúde e as resoluções do CONAMA. Os níveis de radiação natural variaram de 0,0041 ± 0,0004 Bq.L-1 a 0,80 ± 0,04 Bq.L-1 para a atividade alfa total e de 0,045 ± 0,003 a 3,0 ± 0,2 Bq.L-1 para a atividade beta total. Tendo como parâmetro a OMS e o MS, apenas duas amostras de água subterrânea, uma localizada na cidade de Lagoa Real e outra na cidade de Caetité apresentaram concentrações alfa total acima do valor de 0,5 Bq.L-1 descrito em suas recomendações, 0,80 ± 0,04 Bq.L-1 e 0,57 ± 0,03 Bq.L-1respectivamente. Para beta total, três amostras apresentaram níveis de radioatividade acima do limite de 1 Bq.L-1 recomendado pela Organização Mundial de Saúde e estabelecido pelo Ministério da Saúde; 3,0 ± 0,2 Bq.L-1; 1,63 ± 0,13 Bq.L-1 e 1,19 ± 0,07 Bq.L-1 todos situados no município de Lagoa Real. Duas amostras de água subterrânea no município de Caetité apresentaram concentrações de urânio acima do valor de 15 μg.L-1 determinado pelo CONAMA, 20,3 ± 0,3 μg.L-1 e 17,1± 0,3 μg.L-1. Em Lagoa Real, uma amostra apresentou níveis de urânio seis vezes superior ao limite estabelecido pelo Conselho Nacional de Meio Ambiente, 89,5 ± 1,5 μg.L-1. A Organização Mundial da Saúde em 2004 estabeleceu em suas recomendações o limite de 15 μg.L-1 como a concentração máxima de urânio na água potável. Em 2011 a OMS aumentou este limite para 30 μg.L-1. Levando-se em consideração as atuais recomendações da OMS, apenas a concentração de uma amostra de água apresentou níveis de urânio acima do recomendado, 89,5 ± 1,5 μg.L-1 no município de Lagoa Real. / Brazil has the seventh greatest geological uranium reserve in the world with approximately 310 thousand tons. The Lagoa Real Uranium Province, in the region of Caetité and Lagoa Real, situated in South Center Bahia, is considered the most important monomineralic province in Brazil. Urban population who lives in the uranium district in the cities of Caetité, Lagoa Real and Livramento de Nossa Senhora uses drinking water originated from public supply. In the rural area, characterized by frequent draughts, residents receive water from digged and drilled wells and from small dams and reservoirs, as well, which are supplied by the rains. This work determined the levels of total alpha and beta radioactivity and the uranium concentrations in several kinds of water consumed by urban and rural population from the Lagoa Real Uranium Province. Total α e β activities were determined with a low-level gas flow proportional detector. The uranium concentrations were determined with an inductive coupled plasma-mass spectrometer (ICP-MS). The results obtained were confronted with the latest World Health Organizations recommendations from 2011, the ordinance number 2914 of December 12 2011 from the Health Ministry and CONAMAs resolutions. Natural radiation levels varied from 0,0041 ± 0,0004 Bq.L-1 to 0,80 ± 0,04 Bq.L-1 for total alpha activity and from 0,045 ± 0,003 to 3,00 ± 0,2 Bq.L-1 for total beta activity. Having the WHO and the HM as parameter, just two underground water samples, one located in the city of Lagoa Real and the other in the city of Caetité presented total alpha concentration above the value of 0,5 Bq.L-1 described in its recommendations, 0,80 ± 0,040 Bq.L-1 and 0,57 ± 0,03 Bq.L-1 respectively. For total beta three samples presented radioactivity levels above the 1 Bq.L-1 limit recommended by the WHO and established by the Health Ministry; 3,00 ± 0,2 Bq.L-1; 1,63 ± 0,13 Bq.L-1 and 1,19 ± 0,07 Bq.L-1., all of them situated in the Lagoa Real town. Two samples of underground water from Caetité presented uranium concentrations above the value of 15 μg.L-1 determined by CONAMA, 20,3 ± 0,3 μg.L-1 and 17,1± 0,3 μg.L-1. In Lagoa Real one sample presented uranium levels six times over the limit established by the Environment National Council 89,5 ± 1,5 μg.L-1. In 2004 the World Health Organization established in its recommendations the 15 μg.L-1 limit as the maximum uranium concentration in drinking water. In 2011 the WHO increased that limit to 30 μg.L-1. Taking into account the current WHO recommendations only the concentration of one water sample presented uranium levels above the recommended, 89,5 ± 1,5 μg.L-1 in Lagoa Real.

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