On the quantum mechanical propagator for driven coupled harmonic oscillators

The exact propagator beyond and at caustics for a pair of coupled and driven oscillators with different frequencies and masses is calculated using the path-integral approach. The exact wavefunctions and energies are also presented. Finally the propagator is re-calculated through an alternative method, using the δfunction. © 1992 IOP Publishing Ltd.

Social Panorama of Latin America 2010

Includes bibliography

Nonpertubative solutions of massless gauged thirring model

We present a nonperturbative quantization of the two-dimensional massless gauged Thirring model by using the path-integral approach. First, we will study the constraint structure of model via the Dirac's formalism and by using the Faddeev-Senjanovic method we calculate the vacuum-vacuum transition amplitude in a Rξ-gauge, then we compute the Green's functions in a nonperturbative framework. © 2010 American Institute of Physics.

The modernization of bank supervision

Includes bibliography

Thermal phase transition for some spin-boson models

In this work we study two different spin-boson models. Such models are generalizations of the Dicke model, it means they describe systems of N identical two-level atoms coupled to a single-mode quantized bosonic field, assuming the rotating wave approximation. In the first model, we consider the wavelength of the bosonic field to be of the order of the linear dimension of the material composed of the atoms, therefore we consider the spatial sinusoidal form of the bosonic field. The second model is the Thompson model, where we consider the presence of phonons in the material composed of the atoms. We study finite temperature properties of the models using the path integral approach and functional methods. In the thermodynamic limit, N→∞, the systems exhibit phase transitions from normal to superradiant phase at some critical values of temperature and coupling constant. We find the asymptotic behavior of the partition functions and the collective spectrums of the systems in the normal and the superradiant phases. We observe that the collective spectrums have zero energy values in the superradiant phases, corresponding to the Goldstone mode associated to the continuous symmetry breaking of the models. Our analysis and results are valid in the limit of zero temperature β→∞, where the models exhibit quantum phase transitions. © 2013 Elsevier B.V. All rights reserved.

Quantização funcional e renormalizabilidade da eletrodinâmica generalizada

Pós-graduação em Física - IFT

Coesão familiar associada à saúde bucal, fatores socioeconômicos e comportamentos em saúde

Pesquisas sobre saúde geral têm relacionado coesão familiar a fatores socioeconômicos e comportamentais. O objetivo deste estudo foi investigar a associação entre coesão familiar e fatores socioeconômicos, comportamentais e de saúde bucal. Este foi um estudo transversal com amostra por conglomerados em dois estágios. A amostra randomizada de 524 adolescentes era proveniente de escolas públicas da cidade de Piracicaba-SP. As variáveis foram avaliadas por questionários autoaplicáveis e os dados de saúde bucal, pelos índices CPO e CPI. A coesão familiar percebida pelo adolescente foi avaliada por meio da escala de adaptabilidade e coesão familiar. Análise univariada e regressão logística multinominal mostraram que adolescentes com baixa coesão familiar apresentaram mais chance de terem baixa renda (OR 2,28 IC95% 1,14-4,55), presença de cárie (OR 2,23 IC95% 1,21-4,09) e baixa frequência de escovação diária (OR 1,91 IC95% 1,03-3,54). Adolescentes com alta coesão familiar apresentaram mais chance que adolescentes com média coesão de terem alta renda e fator de proteção contra o hábito de tabagismo. Desta forma, a coesão familiar percebida pelo adolescente associou-se com variáveis comportamentais, socioeconômicas e de saúde bucal, indicando a importância de uma abordagem integral da saúde do paciente.

A study of the errors of the averaged models in the restricted three-body problem in a short time scale

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Educação em saúde para atenção à gestante: paralelo de experiências entre Brasil e Portugal

Care practices have raised some questions concerning the attention given to women, specifically when it comes to issues of extreme importance in Public Health's approach of pre-natal care. The present study intends to discuss the scope and challenges of the integral care in maternal health, taking into consideration the experiences of one of the authors in the health scenarios from both Brazil and Portugal. A comparative analysis was conducted on the format of the pre-natal classes offered to groups of pregnant women, a frequent practice of Primary Care in both countries. The method of participant observation of two groups of pregnant women, one in each country was used. The organization of each group is presented and evaluated regarding its methodological and practical settings. The analysis of the experiences indicates that both groups can be considered as informative or educative, since the chosen methodology and structure was formed by lectures with predefined themes; there was reduced reflection and empowerment possibilities, due to the fragmented presentation form, and this could also mean diminished reflection on the changes of the feminine role. It is thus concluded that the need for offering care for women in different periods of their lives should include a continuous fight for an amplified and integral approach, with emphasis in the care network and in health promotion.

Coordenadas vestidas: formulação segundo a interpretação de Dirac-Feynman para a mecânica quântica e aplicações em CQED

Pós-graduação em Física - IFT

Supersymmetric extension of the quantum spherical model

In this work, we present a supersymmetric extension of the quantum spherical model, both in components and also in the superspace formalisms. We find the solution for short- and long-range interactions through the imaginary time formalism path integral approach. The existence of critical points (classical and quantum) is analyzed and the corresponding critical dimensions are determined.

Quantum Einstein gravity - advancements of heat kernel-based renormalization group studies

The asymptotic safety scenario allows to define a consistent theory of quantized gravity within the framework of quantum field theory. The central conjecture of this scenario is the existence of a non-Gaussian fixed point of the theory's renormalization group flow, that allows to formulate renormalization conditions that render the theory fully predictive. Investigations of this possibility use an exact functional renormalization group equation as a primary non-perturbative tool. This equation implements Wilsonian renormalization group transformations, and is demonstrated to represent a reformulation of the functional integral approach to quantum field theory.rnAs its main result, this thesis develops an algebraic algorithm which allows to systematically construct the renormalization group flow of gauge theories as well as gravity in arbitrary expansion schemes. In particular, it uses off-diagonal heat kernel techniques to efficiently handle the non-minimal differential operators which appear due to gauge symmetries. The central virtue of the algorithm is that no additional simplifications need to be employed, opening the possibility for more systematic investigations of the emergence of non-perturbative phenomena. As a by-product several novel results on the heat kernel expansion of the Laplace operator acting on general gauge bundles are obtained.rnThe constructed algorithm is used to re-derive the renormalization group flow of gravity in the Einstein-Hilbert truncation, showing the manifest background independence of the results. The well-studied Einstein-Hilbert case is further advanced by taking the effect of a running ghost field renormalization on the gravitational coupling constants into account. A detailed numerical analysis reveals a further stabilization of the found non-Gaussian fixed point.rnFinally, the proposed algorithm is applied to the case of higher derivative gravity including all curvature squared interactions. This establishes an improvement of existing computations, taking the independent running of the Euler topological term into account. Known perturbative results are reproduced in this case from the renormalization group equation, identifying however a unique non-Gaussian fixed point.rn

Diseño de una metodología CASE de desarrollo de software

En la actualidad existe una gran expectación ante la introducción de nuevas herramientas y métodos para el desarrollo de productos software, que permitirán en un futuro próximo un planteamiento de ingeniería del proceso de producción software. Las nuevas metodologías que empiezan a esbozarse suponen un enfoque integral del problema abarcando todas las fases del esquema productivo. Sin embargo el grado de automatización conseguido en el proceso de construcción de sistemas es muy bajo y éste está centrado en las últimas fases del ciclo de vida del software, consiguiéndose así una reducción poco significativa de sus costes y, lo que es aún más importante, sin garantizar la calidad de los productos software obtenidos. Esta tesis define una metodología de desarrollo software estructurada que se puede automatizar, es decir una metodología CASE. La metodología que se presenta se ajusta al modelo de ciclo de desarrollo CASE, que consta de las fases de análisis, diseño y pruebas; siendo su ámbito de aplicación los sistemas de información. Se establecen inicialmente los principios básicos sobre los que la metodología CASE se asienta. Posteriormente, y puesto que la metodología se inicia con la fijación de los objetivos de la empresa que demanda un sistema informático, se emplean técnicas que sirvan de recogida y validación de la información, que proporcionan a la vez un lenguaje de comunicación fácil entre usuarios finales e informáticos. Además, estas mismas técnicas detallarán de una manera completa, consistente y sin ambigüedad todos los requisitos del sistema. Asimismo, se presentan un conjunto de técnicas y algoritmos para conseguir que desde la especificación de requisitos del sistema se logre una automatización tanto del diseño lógico del Modelo de Procesos como del Modelo de Datos, validados ambos conforme a la especificación de requisitos previa. Por último se definen unos procedimientos formales que indican el conjunto de actividades a realizar en el proceso de construcción y cómo llevarlas a cabo, consiguiendo de esta manera una integridad en las distintas etapas del proceso de desarrollo.---ABSTRACT---Nowdays there is a great expectation with regard to the introduction of new tools and methods for the software products development that, in the very near future will allow, an engineering approach in the software development process. New methodologies, just emerging, imply an integral approach to the problem, including all the productive scheme stages. However, the automatization degree obtained in the systems construction process is very low and focused on the last phases of the software lifecycle, which means that the costs reduction obtained is irrelevant and, which is more important, the quality of the software products is not guaranteed. This thesis defines an structured software development methodology that can be automated, that is a CASE methodology. Such a methodology is adapted to the CASE development cycle-model, which consists in analysis, design and testing phases, being the information systems its field of application. Firstly, we present the basic principies on which CASE methodology is based. Secondly, since the methodology starts from fixing the objectives of the company demanding the automatization system, we use some techniques that are useful for gathering and validating the information, being at the same time an easy communication language between end-users and developers. Indeed, these same techniques will detail completely, consistently and non ambiguously all the system requirements. Likewise, a set of techniques and algorithms are shown in order to obtain, from the system requirements specification, an automatization of the Process Model logical design, and of the Data Model logical design. Those two models are validated according to the previous requirement specification. Finally, we define several formal procedures that suggest which set of activities to be accomplished in the construction process, and how to carry them out, getting in this way integrity and completness for the different stages of the development process.

Caracterização do perfil audiológico de escolares de escola pública do município de Bauru/SP

Muitos dos problemas auditivos não são notados por pais e professores. Este fato prejudica a aprendizagem da criança principalmente no ambiente escolar. Por isso, programas de triagem auditiva podem ser utilizados com o intuito de detectar e, posteriormente, diagnosticar escolares a fim de que se possa prevenir ou minimizar o impacto a que possíveis sequelas auditivas venham prejudicar o rendimento escolar da criança. Hoje em dia podemos contar com programas que permitem o melhor acompanhamento de populações que necessitam de cuidados preventivos e curativos, e a audição é um aspecto muito importante que pode ser avaliado quando estes programas são colocados em prática. O Programa Nacional de Reorientação da Formação Profissional em Saúde (Pró-Saúde), que visou reorientar a formação profissional, teve como objetivo integrar ensino-serviço e promover atenção básica por meio da abordagem integral do processo saúde-doença. Ambientes externos podem ser utilizados por alunos e professores universitários para que possam colocadas em prática ações que possibilitem a humanização das práticas de atenção a saúde e a integralidade das mesmas, por meio da articulação de ações e serviços de saúde, preventivos e curativos, individuais e coletivos. A escola é considerada um dos ambientes que este trabalho pode ser realizado. O Programa Saúde na Escola (PSE) abre o ambiente escolar com a finalidade de contribuir para a formação integral dos estudantes da rede pública de educação básica por meio de ações de prevenção, promoção e atenção à saúde. Sendo um estudo do tipo retrospectivo transversal, como objetivo principal caracterizar o perfil audiológico de escolares de escola pública do município de Bauru SP, contando com a integração de profissionais da área da saúde e educação no ambiente escolar, o que teve como base os programas citados acima. A triagem auditiva foi realizada com a aplicação dos seguintes procedimentos: imitanciometria, inspeção visual do meato acústico externo, emissões otoacústicas por produto de distorção e audiometria tonal liminar. Observou-se que do total de 652 estudantes, a grande maioria (97,1%) dos participantes com faixa etária entre 10 e 18 anos, apresentaram audição normal. Em 2,9% desta população foi encontrada alguma alteração auditiva temporária. Com a exceção de um único participante, portador de perda auditiva sensorioneural. Apesar de encontrarmos muitas crianças e adolescentes com audição normal, o que mais ressalta a importância deste trabalho é a necessidade da triagem auditiva em ambientes escolares e, essencialmente, o acompanhamento das mesmas nesta faixa etária, já que são escassos os estudos referentes a ela. Apesar das poucas alterações auditivas encontradas serem passageiras, são exatamente estas que interferem no bom rendimento escolar e outros fatores.

An iterative method based on boundary integrals for elliptic Cauchy problems in semi-infinite domains

In this study, we investigate the problem of reconstruction of a stationary temperature field from given temperature and heat flux on a part of the boundary of a semi-infinite region containing an inclusion. This situation can be modelled as a Cauchy problem for the Laplace operator and it is an ill-posed problem in the sense of Hadamard. We propose and investigate a Landweber-Fridman type iterative method, which preserve the (stationary) heat operator, for the stable reconstruction of the temperature field on the boundary of the inclusion. In each iteration step, mixed boundary value problems for the Laplace operator are solved in the semi-infinite region. Well-posedness of these problems is investigated and convergence of the procedures is discussed. For the numerical implementation of these mixed problems an efficient boundary integral method is proposed which is based on the indirect variant of the boundary integral approach. Using this approach the mixed problems are reduced to integral equations over the (bounded) boundary of the inclusion. Numerical examples are included showing that stable and accurate reconstructions of the temperature field on the boundary of the inclusion can be obtained also in the case of noisy data. These results are compared with those obtained with the alternating iterative method.