960 resultados para Sophia de Mello Breyner Andresen
Resumo:
A novel method is proposed to treat the problem of the random resistance of a strictly one-dimensional conductor with static disorder. For the probability distribution of the transfer matrix R of the conductor we propose a distribution of maximum information entropy, constrained by the following physical requirements: (1) flux conservation, (2) time-reversal invariance, and (3) scaling with the length of the conductor of the two lowest cumulants of ω, where R=exp(iω→⋅Jbhat). The preliminary results discussed in the text are in qualitative agreement with those obtained by sophisticated microscopic theories.
Resumo:
This thesis examines the mythology in and social reality behind a group of texts from the Nag Hammadi and related literature, to which certain leaders of the early church attached the label, Ophite, i.e., snake people. In the mythology, which essentially draws upon and rewrites the Genesis paradise story, the snake's advice to eat from the tree of knowledge is positive, the creator and his angels are demonic beasts and the true godhead is depicted as an androgynous heavenly projection of Adam and Eve. It will be argued that this unique mythology is attested in certain Coptic texts from the Nag Hammadi and Berlin 8502 Codices (On the Origin of the World, Hypostasis of the Archons, Apocryphon of John, Eugnostos, Sophia of Jesus Christ), as well as in reports by Irenaeus (Adversus Haereses 1.30), Origen (Contra Celsum 6.24-38) and Epiphanius (Panarion 26). It will also be argued that this so-called Ophite evidence is essential for a proper understanding of Sethian Gnosticism, often today considered one of the earliest forms of Gnosticism; there seems to have occurred a Sethianization of Ophite mythology. I propose that we replace the current Sethian Gnostic category by a new one that not only adds texts that draw upon the Ophite mythology alongside these Sethian texts, but also arranges the material in smaller typological units. I also propose we rename this remodelled and expanded Sethian corpus "Classic Gnostic." I have divided the thesis into four parts: (I) Introduction; (II) Myth and Innovation; (III) Ritual; and (IV) Conclusion. In Part I, the sources and previous research on Ophites and Sethians will be examined, and the new Classic Gnostic category will be introduced to provide a framework for the study of the Ophite evidence. Chapters in Part II explore key themes in the mythology of our texts, first by text comparison (to show that certain texts represent the Ophite mythology and that this mythology is different from Sethianism), and then by attempting to unveil social circumstances that may have given rise to such myths. Part III assesses heresiological claims of Ophite rituals, and Part IV is the conclusion.
Resumo:
A detailed study is presented of the expected performance of the ATLAS detector. The reconstruction of tracks, leptons, photons, missing energy and jets is investigated, together with the performance of b-tagging and the trigger. The physics potential for a variety of interesting physics processes, within the Standard Model and beyond, is examined. The study comprises a series of notes based on simulations of the detector and physics processes, with particular emphasis given to the data expected from the first years of operation of the LHC at CERN.
Resumo:
We study the relaxation of a degenerate two-level system interacting with a heat bath, assuming a random-matrix model for the system-bath interaction. For times larger than the duration of a collision and smaller than the Poincaré recurrence time, the survival probability of still finding the system at timet in the same state in which it was prepared att=0 is exactly calculated.
Resumo:
We present a theory of multichannel disordered conductors by directly studying the statistical distribution of the transfer matrix for the full system. The theory is based on the general properties of the scattering system: flux conservation, time-reversal invariance, and the appropriate combination requirement when two wires are put together. The distribution associated with systems of very small length is then selected on the basis of a maximum-entropy criterion; a fixed value is assumed for the diffusion coefficient that characterizes the evolution of the distribution as the length increases. We obtain a diffusion equation for the probability distribution and compute the average of a few relevant quantities.
Resumo:
Stochastic hybrid systems arise in numerous applications of systems with multiple models; e.g., air traffc management, flexible manufacturing systems, fault tolerant control systems etc. In a typical hybrid system, the state space is hybrid in the sense that some components take values in a Euclidean space, while some other components are discrete. In this paper we propose two stochastic hybrid models, both of which permit diffusion and hybrid jump. Such models are essential for studying air traffic management in a stochastic framework.
Resumo:
The rapid disruption of tropical forests probably imperils global biodiversity more than any other contemporary phenomenon(1-3). With deforestation advancing quickly, protected areas are increasingly becoming final refuges for threatened species and natural ecosystem processes. However, many protected areas in the tropics are themselves vulnerable to human encroachment and other environmental stresses(4-9). As pressures mount, it is vital to know whether existing reserves can sustain their biodiversity. A critical constraint in addressing this question has been that data describing a broad array of biodiversity groups have been unavailable for a sufficiently large and representative sample of reserves. Here we present a uniquely comprehensive data set on changes over the past 20 to 30 years in 31 functional groups of species and 21 potential drivers of environmental change, for 60 protected areas stratified across the world's major tropical regions. Our analysis reveals great variation in reserve `health': about half of all reserves have been effective or performed passably, but the rest are experiencing an erosion of biodiversity that is often alarmingly widespread taxonomically and functionally. Habitat disruption, hunting and forest-product exploitation were the strongest predictors of declining reserve health. Crucially, environmental changes immediately outside reserves seemed nearly as important as those inside in determining their ecological fate, with changes inside reserves strongly mirroring those occurring around them. These findings suggest that tropical protected areas are often intimately linked ecologically to their surrounding habitats, and that a failure to stem broad-scale loss and degradation of such habitats could sharply increase the likelihood of serious biodiversity declines.
Resumo:
Apresenta uma resenha sobre o volume 2 da publicação - Os sucessores do Barão: relações exteriores do Brasil, 1912-1964 - que aborda a história das relações internacionais e da política externa do Brasil durante o regime militar, cobrindo tanto os episódios diplomáticos quanto os relativos ao quadro político e econômico mundial.
Resumo:
Aborda o tema da segurança da informação. Utiliza modelos como o COBIT e bibliotecas de melhores práticas como o ITIL (Information Technology Infraestructure Library) para identificar o grau de maturidade da empresa e o valor da informação na estrutura gerencial e no poder decisório nos níveis operacional, tático e estratégico.
Resumo:
Discute o instituto da iniciativa popular constitucional a partir da reunião das manifestações sobre o assunto, desde as emendas populares que trataram do assunto na Assembleia Constituinte (1987) à adoção da iniciativa popular constitucional nas Constituições Estaduais e suas respectivas emendas populares já aprovadas.
Resumo:
Analisa a atuação do Poder Legislativo no controle da edição de medidas provisórias no decorrer de sua tramitação, sobretudo na Câmara dos Deputados, a partir da promulgação da Emenda Constitucional n° 32 de 2001. Aborda as dimensões jurídica, política, social e econômica, de modo a aferir o desempenho dessa vertente de controle e as suas implicações sobre o ímpeto legiferante do Poder Executivo.
Resumo:
Analisa a figura do crédito adicional extraordinário veiculado por medida provisória. A abordagem tem como foco principal constatar se o Poder Executivo, quando edita medida provisória objetivando crédito extraordinário, vem observando os pressupostos necessários, como prescreve a Constituição Federal. Para tanto, efetua-se uma análise detida desses requisitos constitucionais e da natureza jurídica de ambos os institutos, com atenção a alguns dos princípios constitucionais atinentes ao assunto, notadamente em relação ao da legalidade, sem perder de vista as situações que reclamam a utilização de crédito extraordinário. Apresenta também uma rápida visão histórica da origem institucional do parlamento, a fim de se desvendar as razões para a sua criação. Avalia ainda as consequências do controle político e do controle jurisdicional exercido sobre essa prática do Presidente da República de expedir medidas provisórias para abertura de crédito extraordinário. Para alicerçar a pesquisa busca socorro na exegese da Carta Constitucional vigente, bem como na doutrina e na jurisprudência específicas.
Resumo:
Análise crítica da tramitação das medidas provisórias, com ênfase à viabilidade da sua apreciação inicialmente por uma única comissão mista permanente, com avaliação da admissibilidade da matéria. Para tanto, foram utilizados como parâmetros o art. 62 da Constituição Federal de 1988 e a Resolução n° 1, de 2002, do Congresso Nacional, e feita uma análise comparativa com a estrutura semelhante no Poder Legislativo da Itália. Destaca alguns mecanismos sugeridos pela PEC n° 511, de 2006 e apensados, que poderão contribuir para diminuir o número de MP editadas e valorizar sua discussão no âmbito da Comissão Mista.