Aplicações da teoria da percolação à modelagem e simulação de reservatórios de petróleo

In this thesis we study some problems related to petroleum reservoirs using methods and concepts of Statistical Physics. The thesis could be divided percolation problem in random multifractal support motivated by its potential application in modelling oil reservoirs. We develped an heterogeneous and anisotropic grid that followin two parts. The first one introduce a study of the percolations a random multifractal distribution of its sites. After, we determine the percolation threshold for this grid, the fractal dimension of the percolating cluster and the critical exponents ß and v. In the second part, we propose an alternative systematic of modelling and simulating oil reservoirs. We introduce a statistical model based in a stochastic formulation do Darcy Law. In this model, the distribution of permeabilities is localy equivalent to the basic model of bond percolation

Teorias f(R) de gravidade na formulação de Palatini

In this dissertation, after a brief review on the Einstein s General Relativity Theory and its application to the Friedmann-Lemaitre-Robertson-Walker (FLRW) cosmological models, we present and discuss the alternative theories of gravity dubbed f(R) gravity. These theories come about when one substitute in the Einstein-Hilbert action the Ricci curvature R by some well behaved nonlinear function f(R). They provide an alternative way to explain the current cosmic acceleration with no need of invoking neither a dark energy component, nor the existence of extra spatial dimensions. In dealing with f(R) gravity, two different variational approaches may be followed, namely the metric and the Palatini formalisms, which lead to very different equations of motion. We briefly describe the metric formalism and then concentrate on the Palatini variational approach to the gravity action. We make a systematic and detailed derivation of the field equations for Palatini f(R) gravity, which generalize the Einsteins equations of General Relativity, and obtain also the generalized Friedmann equations, which can be used for cosmological tests. As an example, using recent compilations of type Ia Supernovae observations, we show how the f(R) = R − fi/Rn class of gravity theories explain the recent observed acceleration of the universe by placing reasonable constraints on the free parameters fi and n. We also examine the question as to whether Palatini f(R) gravity theories permit space-times in which causality, a fundamental issue in any physical theory [22], is violated. As is well known, in General Relativity there are solutions to the viii field equations that have causal anomalies in the form of closed time-like curves, the renowned Gödel model being the best known example of such a solution. Here we show that every perfect-fluid Gödel-type solution of Palatini f(R) gravity with density and pressure p that satisfy the weak energy condition + p 0 is necessarily isometric to the Gödel geometry, demonstrating, therefore, that these theories present causal anomalies in the form of closed time-like curves. This result extends a theorem on Gödel-type models to the framework of Palatini f(R) gravity theory. We derive an expression for a critical radius rc (beyond which causality is violated) for an arbitrary Palatini f(R) theory. The expression makes apparent that the violation of causality depends on the form of f(R) and on the matter content components. We concretely examine the Gödel-type perfect-fluid solutions in the f(R) = R−fi/Rn class of Palatini gravity theories, and show that for positive matter density and for fi and n in the range permitted by the observations, these theories do not admit the Gödel geometry as a perfect-fluid solution of its field equations. In this sense, f(R) gravity theory remedies the causal pathology in the form of closed timelike curves which is allowed in General Relativity. We also examine the violation of causality of Gödel-type by considering a single scalar field as the matter content. For this source, we show that Palatini f(R) gravity gives rise to a unique Gödeltype solution with no violation of causality. Finally, we show that by combining a perfect fluid plus a scalar field as sources of Gödel-type geometries, we obtain both solutions in the form of closed time-like curves, as well as solutions with no violation of causality

Inserção de fornecedores locais como fonte de desempenhos em custos de transação e legitimidade: estudo de caso na cadeia produtiva do petróleo e gás do Rio Grande do Norte

The inclusion of local suppliers in production chains has considerable impact on its performance, but most notably in its main actors. The results of this process may be of different kinds and can be analyzed from economic or institutional approaches. This study aimed to verify the existence of different performances of Petrobras due to the inclusion of local suppliers in the oil and gas production chain in the state of Rio Grande do Norte, from the viewpoints of transaction costs and the Institutional Theory. In order to this, were made the characterization of the PROMINP, the description of its actions and results, the mapping of its institutional context of reference, and identification of results obtained by Petrobras in terms of transaction costs and legitimacy. The theoretical framework is based on authors dealing with industrial concentration, as like Marshall, Krugman, Porter and Schmitz, from the sociological perspective of neoinstitucional theory, as like DiMaggio and Powell and Scott and Meyer, and transaction costs, as like Williamson. This is a qualitative research, with data collection done by consulting secondary fonts and semi-structured interviews with nineteen actors of three groups, namely: actors involved in actions of the program, representatives of enterprises and representative of Petrobras. To analyze the content was used the Suchman s model (1995) for categories associated with strategies of legitimation and fourteen variables associated with the three variables assets specificity, bounded rationality and opportunism (Williamson, 1995, 1989) in the case of transaction costs. The results indicate that PROMINP has achieved its objectives by encouraging the increased participation of local companies in the oil and gas production chain, reflecting in the economic development of the state. The Redepetro/RN, fostered and built upon the interaction of the participants, is presented as a solution of continuity to the participation of enterprises in the chain, after the closure of the actions of the program. PROMINP demands responses to coercive, legislative and regulatory pressures of the organizational field, whose institutional context of reference is wide. From the point of view of legitimacy, through strategies to gain cognitive legitimacy and maintaining pragmatic legitimacy, Petrobras can manipulate the environment, ensuring the compliance of the constituents to their technical and institutional demands. Enterprises, in turn, respond to the demands through compliance with technical demands, mainly through the certification of processes, and cultural changes. There aren t clear gains related to the transaction costs, however, gains in legitimacy can be seen as a cumulative capital that can serve as a competitive differential that generates economic gains. In terms of theoretical findings, it was found that, due to its explanatory power for actions that are difficult to explain only in economic terms, Institutional Theory may be used as theoretical support concurrent with other theories. TCE model has limitations in explaining the program actions. In the case, it s emphasized that Petrobras doesn t seek only economic efficiency, but has in its mission the commitment to social development.

Modelo de decisão multicritério para seleções interciclo das universidades novas: estudo na Universidade Federal do Rio Grande do Norte

The discussions wherein develop proposals for university reform in Brazil include, among other things, the conception of the university titled "New University", whose structural origin comes from the bill of higher education reform and unification of the foundations of education European upper (Bologna process). At its core, the Bologna process has imposed a series of transformations, among which, the promotion of mobility, as a stimulus to interinstitutional cooperation to enable an better and bigger qualification of the students. Nevertheless, what we see is that this point is one of the main points made flawed by Brazilian institutions that have adopted this model of higher education. An example is the Bachelor of Science and Technology - BC&T, Federal University of Rio Grande do Norte - UFRN, where there are problems of the internal order, represented by the problem of the reusing of the disciplines, such also of external order, in cases of transfers interinstitutional. Because of this, and knowing that this is a typical problem in which multiple criteria are involved, the aim of this study is to propose a multicriteria model for selection of interciclo of the BC&T of the UFRN which addresses the issue of mobility. For this, this study was of exploratory and study case nature, use as tools of data collection, the bibliographic and documentary research, as well as semi-structured interviews. For the elaboration of the model, were used the five phases most commonly used in the modeling of problems in operational research in a sample of 91 students of BC&T. As a result, we obtained a model that addresses the issue of internal and external mobility of the school and that, moreover, was also more robust and fair than the current model of BC&T and also what is used in other courses of the UFRN, taking into consideration the expected results by the decision makers

Hemiparesia congênita e adquirida na criança: interrelação entre presença de crises epilépticas, os achados eletrencefalográficos e de neuroimagem por ressonância nuclear magnética

The purpose of this paper was to study patients with congenital and acquired hemiparesis, their clinical aspects, the presence or not of epileptic seizures, and electroencephalographic (EEG) and Magnetic Resonance Imaging (MRI) findings. We analyzed the interrelation between etiology, the presence and seriousness of epileptic seizures (ES) and the possible causes of refractoriness. This is a prospective study using the clinical diagnosis of a child neurologist, who attested to the presence of unilateral motor lesions. We compared the electroencephalographic findings in patients with or without epileptic seizures, and investigated if among the former, these seizures were controlled or not, their likely etiology and risks of refractoriness. EEG background activity on the lesion and contralateral side was analyzed, in addition to the presence of concomitant epileptiform activity. Encephalon MRIs of all the patients were studied to correlate etiology and the control or not of epileptic seizures. The disorganization of bilateral EEG activity correlated with the difficult-to-control epileptic seizures. Suitably organized background activity contralateral to the lesion is a good prognosis in relation to epileptic seizures. Focal epileptogenic activity does not necessarily predispose to epileptic manifestation. The MRI is more important in determining etiology than in prognosing epileptic seizures. This study used a multidisciplinary approach involving child neurologists, a physical therapist and a neuroradiologist. This meets the criteria of multidisciplinarity of the Postgraduate Program in Health Sciences

Efetividade da terapia fisica descongestiva na cicatrização de úlceras venosas

A venous ulcer is the most serious clinical manifestation of chronic venous failure, and the most frequent in lower limbs, accounting for 70% of all ulcers. Patients may suffer from this infirmity for several years without healing of the lesion if treatment is inadequate. The aim of this investigation was to verify the effectiveness of decongestive physical therapy in the healing of venous ulcers. This is a quasi-experimental, interventionist study, with paired, non-probabilistic sampling, composed of 50 patients divided into two groups: control and intervention, each composed of 25 patients. Both groups were identically treated for six months with daily dressings and the latter also underwent complex physical therapy consisting of a combination of the following techniques: manual lymphatic drainage, compression bandaging, lower limb elevation, myolymphokinetic exercises and skin care. The study was approved (Protocol no. 59/2007) by the Ethics Committee of the State University of Southeast Bahia. The Mann-Whitney and Chi-square tests were applied for data analysis. After statistical analysis the patients who underwent therapy showed a statistically significant difference with respect to wound contraction starting in the second month of treatment. Compared to the control, the intervention group showed a greater reduction in both pain and edema starting in the third and fourth month of therapy, respectively. To reinforce these findings, the mean percentage of tissue present at the base of the ulcer (granulation/fibrin ratio) was calculated. The intervention group showed greater granulation at the base of the ulcer compared to the control, significant from the second month of treatment on. It was observed in this study that lymphotherapy, when compared between the intervention and control groups, accelerated the healing process, and reduced pain and edema in the affected limbs. It is expected, therefore, that these results widen scientific knowledge and we suggest that this therapy be used 78 not only to reduce lymphedema, but also as a treatment option for venous ulcers, given its easy application and low cost. The data, therefore, demonstrated the importance of basic care on the part of a multiprofessional and transdisciplinary health team involved in the healing process of these infirmities, thereby contributing to better quality of life in these individuals

A transformação da Associação de Professores do Rio Grande do Norte (APRN) em Sindicato dos Trabalhadores em Educação (1986-1990)

El estudo que ahora apresentamos habla a respecto ala transformaçión de la Asociación de maestros del Rio Grande del Norte (APRN en sindicato de los trabajadores en educación (SINTE) en el período de 1986 1990. Tratase basicamiente de las razones que llebaran historicamente la APRN la reorganizar sus luchas, su cultura política y el su movimiento reivindicatório; que impulsionaran la construción del próprio sindicato el único de la categoria, após el regime militar em el país especialmente en el gobierno Sarney, y en el ánbito estadual com la resistência la política econômica y la repreción policial del gobierno Geraldo Melo, la época. El estudo también apunta algunas caraterísticas marcantes del contexto histórico de la educación nacional, enfatizando la asención de la escuela nueva en el Brasil en las décadas de 1920 y 1930, inclusive delante del movimiento sindical, controlado por el gobierno Vargas que tênia uma praetica corporativista. Es importante decir que esas características estavan juntas del contexto local, en el rato en que se percebia la primer gestan del prof Anfilóquio Cámara, como el primer presidente de la APRN, al partir de la su fundación (1920), y que tênia um relacionamento bastante estrecho com el poder público estadual de caráter liberal. Habia una discución sobre la abertura política y la atuación política de las clases médias brasileñas ya em 1979, y al mismo tiempo analisabase el desencandeamiento del nuevo sindicalismo en el ABC Paulista, mientras uno movimiento sindical, autônomo y democrático que tênia el objetivo de juntar lãs luchas de los operários dentro y fuera de las fábricas reivindicando basicamiente: la redución de la jornada del trabajo, reajuste de sueldo y condición del trabajo, bien como lãs sus consecuencias para el movimiento de los educadores potigurares. Al hacer en septembre de 1989, el sindicato de los trabajadores en educación del Rio Grande del Norte se desvincula definitivamiente de uma estructura sindical vertical (tradicional), que la ex-APRN herdo al longo de su História del gobierno Vargas, siempre controlada pelo Estado y que en las décadas de 1980 y 1990 fue fortalecido por la CNTE (Confederación Nacional de los Trabajadores en la, educación), principalmente, a partir del Congreso Nacional de Unificación de los Trabajadores en la Educación, realizado en Aracaju/SE em el período de 25 a 28 de enero de 1990 en el sentido tambien de las sus principais reivindicaciones: escuela pública, gratuita y de cualidades en todos los pasos, verbas públicas solamiente para las escuelas públicas, reposición de los reajustes de sueldo, condición del trabajo, sueldo unificado nacional y la eradicación del analfabetismo

A previdência rural universalista e a sua relevância na economia dos municípios do Rio Grande do Norte

This study deals with the rural social security Universalist established by the Constitution of 1988 and its importance in the economy of the municipalities of Rio Grande do Norte. In this context, the study seeks to satisfy two important criteria that guide the selection of objects of social science research: a consideration of issues that have relevance to the real world and the intention to make the contribution to the scholarly literature on theoretical and empirical aspects. The research seeks to reveal what is the economic importance of the subsystem of social security for rural municipalities in RN. The hypothesis is that the transfer of income received by beneficiaries from the rural social security tax exceeds the explicit mechanisms for most municipalities in RN, in many cases significantly, proving the importance of this policy as a mechanism for combating poverty and reducing social inequality, especially before the fragility of the federal system on the national political entity hall. The study presents theoretical cores - chapters 1-3 - and empirical - Chapter 4. The first core is about the evolution of social protection as a state policy, addressing the influential theories and typologies of the State of Social Welfare and the characteristics of the Brazilian social security model, but mainly, its rural social security subsystem, its history until universalistic model inaugurated by the Federal Constitution of 1988. The second begins with an overview of studies that have emphasized the impact of Social Security on the local economy of small municipalities, then passing data and statistics in order to gauge the socioeconomic importance of pension income in the rural municipalities of Rio Grande do Norte. To this end, the final chapter provides a comparison of the monetary value transferred by the payment of social security benefits - rural and urban - to each of the 167 municipalities in RN with the equally important sources of income in the budget of municipal entities. Apart from their own tax revenues, are objects of comparison with the value of pension benefits awarded in RN, transfer quota state relating to the municipality on the federal ICMS and the transfer on the FPM

O princípio constitucional do desenvolvimento sustentável: análise da sua concretização no Estado do Rio Grande do Norte

The Article 225 of Constitution of the Federative Republic of Brazil in its main body, stipulates that everyone is entitled to ecologically balanced environment and the use of common people and essential to the healthy quality of life, should be imposed on public authorities and the community the duty to defend it and preserve it for present and future generations. Following a universal trend, the letter raised the Brazilian environment the category of one of those values ideals of social order, dedicating it, along with a constitution of rules sparse, a chapter, itself, which definitely, institutionalized the right to healthy environment as a fundamental right of the individual. The national public policies and state should be in line with modern theories of Sustainable Development, outlined within the international society, and certainly instruments that should be made effective through the mobilization of civil society as a whole. The implementation of Human Rights, in fact, depends on a strong political action and not just a legal problem. Thus, this work of theoretical-descriptive nature we will address various dimensions of sustainable development, such as environmental education, water, sanitation, health and sustainable development plans, evaluating its current stage in our state

Estrutura genética populacional de Heliconius erato e Heliconius melpomene (Lepidoptera: Nymphalidae) em fragmentos de Mata Atlântica do Rio Grande do Norte

Extensive studies using molecular markers on butterflies have shown how a highly fragmented landscape may result in the reduction of gene flow among patches of habitat and, consequently, increase genetic differentiation among populations. However, little is known about Heliconius geographical structure and the effects of fragmentation on the connectivity of populations. Furthermore, findings on the effects of the population structure on the dynamics of mimicry evolution in Heliconius butterflies need to be tested in H. erato and H. melpomene specimens found in other locations other than Central and northern South Americas. For the present study, we had two motivations: (1) compare the population structure of H. erato and H. melpomene given the highly fragmented Brazil s Atlantic Forest habitat; and (2) studying population structure of co-mimics could give us insights into the dynamics of mimicry evolution. For this, we analysed the spatial structure and connectivity of eight populations of Heliconius butterflies, in a total of 137 H. erato specimens and 145 H. melpomene specimens, using nine microsatellites loci, 1144 AFLPs markers and 282 mitochondrial DNA sequences. In general, both species exhibited evidence of population subdivision but no isolation by distance indicating some extent of genetic differentiation among populations. Contrary to Kronforst & Gilbert s (2008) Costa Rican Heliconius, H. melpomene exhibited more genetic differentiation than H. erato based on nuclear markers. However, for mitochondrial DNA, H. erato populations showed more genetic differentiation than H. melpomene. Our results corroborate to other studies on Heliconius butterflies concerning the pronounced population subdivision and local genetic drift found in this genus. Nevertheless, the pattern of this differentiation varies significantly from the pattern found in studies conducted in Central America, where H. erato is generally more differentiated and structured than H. melpomene, based on nuclear markers. This different pattern may reflect different evolutionary histories of Heliconius species in Northeastern Brazil s Atlantic Forest

Ectoparasitos associados a aves de um fragmento de Floresta Estacional Decidual no Rio Grande do Norte, Brasil

This study to aimed investigate the community of ectoparasites associated with birds in the Mata do Olho D água, in the municipality of Macaíba, Rio Grande do Norte (RN), Brazil, its structure and the ambiental and hosts influential variables on it, and to verify microhabitats preferences by species of chewing lice and feather mites. We examined 172 individuals belonging to 38 species of Passeriformes and non-Passeriformes. 12 new geographic records are reported and 11 host-parasite associations not yet known for chewing lice and feather mites species. Significant relationship was found between the abundance of chewing lice and the variables total length (r = 0.29, p <0.05) and exposed culmen (r = 0.38, p <0.05) of the hosts. A principal component (PC1) accounted for 90.1% of the hosts morphological variation was significantly influential on the abundance of chewing lice (p <0.05), indicating that the morphological characteristics of the hosts may be positively influencing the abundance of these ectoparasites. Significantly higher frequency of individuals with high loads of chewing lice was detected during the dry period (x ² = 8.5, p <0.05), corroborating studies that propose that birds of arid environments suffer as much pressure as those of parasitic humid environments. Analyses of null models of co-occurrence and niche overlap showed a high degree of structure in the feather mites and chewing lice assemblies, when compared with other groups, and preferences in the use of microhabitats by taxa identified. These results corroborate ecological theories in host-parasite systems, contribute to the knowledge of ectoparasites associated with neotropical birds, and the need for experimental studies, as well as further deepening the biology of these arthropods

Caminhos e descaminhos dos municípios produtores de petróleo: o papel dos royalties no desempenho das finanças públicas municipais no estado do Rio Grande do Norte

It analyzes the magnitude, the nature and the direction of public revenues and the public expenses in oil and natural gas producing municipalities in the state of Rio Grande do Norte in the post-constituent period, and, more precisely, from the approval of Law 9.478/97, called Oil Law . It argues the fiscal federalism normative theory, the typology and the role of the intergovernamental transferences in the performance of the public finances of the local governments. Shows that the economy of Rio Grande do Norte went through deep social-economic changes in the last few decades, among which includes the discovery of the oil and the natural gas and its importance for the growth of the industrial and services sectors. It points out that the increase of the production and the international price of the oil contributed for the growth in revenues of royalties and the special participation in the beneficiary cities, what did not mean an automatic increase in the resources destined to the investment and in the quality on the provision of the goods and services come back toward the local development. On the contrary, the main conclusion of the work is that the trajectory of the oil producing municipalities is marked by paths and embezzlements in the performance of the public finances and in the provision of public goods and services. Paths, that lead to the improvement of the performance of the public finances and the quality of the public goods and services. Embezzlements, that lead to the inefficiency in the provision of goods and services and the capture of the public resources. That is, the fiscal decentralization is a necessary condition, however not enough to improve the amount and the quality of the public goods and services given by these municipalities. For that it is necessary to advance in the fiscal federalism normative theories, in search of optimum model of federalism in local governments where still predominated by patrimonialism, clientelism, fiscal illusion and the capture of the public resources in benefit of the private interests

Uma abordagem institucional da carcinicultura do Rio Grande do Norte de 1999 a 2009

This study analyzes the institucional environment and its changes around the carcinicultora activity in Rio Grande do Norte from the understanding of its trajectory and the macroinstitucional elements micron and that characterizes the activity in the period of 1999 the 2009. In the analysis of the occured institucional changes in the carcinicultura the Guaraíra Estuary is overcome as space reference, located in the eastern coast of the Rio Grande of the North. The analysis proposal has for base the adoption of the conceptual support of the innovative institucionalistas and neoshumpterianas theories, for understanding that these bring complementary and enriching elements that will allow an analysis, not static, but, dynamics of the carcinicultora activity. It was verified that the crisis brought up for the antidumping action, for the problems of the illnesses that had abated the shrimp, for the depreciation of the Real, among others it led to an overturn in the productive conjuncture of market and forced the alteration of the effective institutions. This institucional alteration, goes in the direction to search to take care of the new demands of the carcinicultura that was possible for the solidity of the institucional foundations constructed throughout the thirty previous years and the consequent consolidation of the composed institucional apparatus for rich a mix of organizations, not only for agencies of government, as well as for organizations with social representation

Efeitos das transferências intergovernamentais sobre as finanças públicas dos municípios do Rio Grande do Norte (2001-2010)

The Brazilian tax structure has specific characteristics and the performance level of government. The autonomy given to municipalities to manage their activities after the 1988 Constitution, made them highly dependent on intergovernmental transfers of resources, revealing the fragility of the administrative capacity of these entities. The vertical gap revealed by the constitutional structure of the Brazilian fiscal federalism model contributes to the formation of this specific feature that you are eroding the tax base and the ability of municipal own revenues. Although there was a better regulation of these transfers after the enactment of the Fiscal Responsibility Law, it is observed that the amount of resources transferred to the municipalities of Rio Grande do Norte is very high and is the main source of revenue of municipalities. In light of the theory of federalism and fiscal decentralization, in particular, the theories related to intergovernmental transfers, we seek to diagnose the transfers from the systematization of information on the origin, destination and value. We used the econometric model of System Dynamic Panel GMM in making the diagnosis and verification of the impact of transfers on public finances of the municipalities of the newborn, associated with a review in light of the theory of fiscal federalism and intergovernmental transfers. The paper presents some proposals for the transfer system and the composition of spending in order to contribute to greater tax efficiency

Relações entre teorias da história e ensino de história: a compreensão de professores

This thesis has as an objective to think over the teachers` understanding of the school History of the Fundamental Teaching regarding the existent relations between the history theories and the teaching of the school History, as well as to think over how these teachers see the influence that their teaching practice gets from the history theories. The work is based on the postulates of the qualitative research and on the characteristics of the ethnography of the school practice. The main procedures of data gathering were the documental analysis, the semi-structured interviews, the field diary and the observations of classes. The scientific perspective of the multiple references is an important source in this research. The participants of this work are two teachers of the school district of Natal who work in the field of the school History in two schools on the North Side of the city. The accomplished analysis point to significant indications that didn't occur continuous and regular teaching situations in the initial and continuing education of these teachers that clearly showed the relations between the history theories and the teaching of the school History. They also suggest that their understanding about the influence that their teaching practice gets from the history theories, is not still explicit. We understand that the relations between the history theories and the teaching of the school History are important for the initial and continuing education of these teachers who belong in this knowledge field, even when these relations are not explicitly pointed by the teachers, because they will always influence the teaching practice that the teachers of the school History build