A TV DIGITAL DIVULGADA NO BOLETIM ELETRÔNICO DO FNDC: UM ESTUDO SOBRE O COMPORTAMENTO DA MÍDIA NA IMPLANTAÇÃO DA TV DIGITAL NO BRASIL

Implantada no Brasil na década de 50, a TV a mídia de maior abrangência e poder ideológico entre seus públicos encara sua segunda grande transformação: ela deixa de ser analógica e passa a ser digital. Com isso, traz à tona novas possibilidades de recepção e a possível convergência de meios. Nesse contexto, o objetivo deste estudo foi analisar o processo de instalação do Sistema Brasileiro de Televisão Digital Terrestre (SBTVD-t) a partir do clipping on-line do Fórum Nacional pela Democratização da Comunicação (FNDC). A análise desse material teve como foco averiguar se o FNDC foi tendencioso ou não na veiculação de matérias voltadas aos aspectos técnicos da nova tecnologia, em detrimento de seu potencial social. Para tanto, optou-se por uma pesquisa de base quantitativa em que as informações e os dados coletados levaram à constatação de que o FNDC se mostra pouco eficaz como aparato crítico-apreciativo da grande mídia, além de não cumprir alguns de seus objetivos ao reproduzir discursos e ideologias de outros veículos. Da mesma forma, verificou-se ainda que o Governo Federal também fugiu aos objetivos listados nos decretos presidenciais que instituem e dispõem sobre a implantação do SBTVD.(AU)

A TV DIGITAL DIVULGADA NO BOLETIM ELETRÔNICO DO FNDC: UM ESTUDO SOBRE O COMPORTAMENTO DA MÍDIA NA IMPLANTAÇÃO DA TV DIGITAL NO BRASIL

Implantada no Brasil na década de 50, a TV a mídia de maior abrangência e poder ideológico entre seus públicos encara sua segunda grande transformação: ela deixa de ser analógica e passa a ser digital. Com isso, traz à tona novas possibilidades de recepção e a possível convergência de meios. Nesse contexto, o objetivo deste estudo foi analisar o processo de instalação do Sistema Brasileiro de Televisão Digital Terrestre (SBTVD-t) a partir do clipping on-line do Fórum Nacional pela Democratização da Comunicação (FNDC). A análise desse material teve como foco averiguar se o FNDC foi tendencioso ou não na veiculação de matérias voltadas aos aspectos técnicos da nova tecnologia, em detrimento de seu potencial social. Para tanto, optou-se por uma pesquisa de base quantitativa em que as informações e os dados coletados levaram à constatação de que o FNDC se mostra pouco eficaz como aparato crítico-apreciativo da grande mídia, além de não cumprir alguns de seus objetivos ao reproduzir discursos e ideologias de outros veículos. Da mesma forma, verificou-se ainda que o Governo Federal também fugiu aos objetivos listados nos decretos presidenciais que instituem e dispõem sobre a implantação do SBTVD.(AU)

Extension of the thermodynamics of small systems to open metastable states: An example

By using a simplified model of small open liquid-like clusters with surface effects, in the gas phase, it is shown how the statistical thermodynamics of small systems can be extended to include metastable supersaturated gaseous states not too far from the gas–liquid equilibrium transition point. To accomplish this, one has to distinguish between mathematical divergence and physical convergence of the open-system partition function.

Climatic evolution of eastern South America during the last deglaciation: a paleoceanographic approach

Para dar suporte ao atual debate sobre as consequências climáticas da liberação antropogênica de CO2 na atmosfera, o refinamento do conhecimento sobre mudanças climáticas e oceanográficas no passado é necessário. A Circulação de Revolvimento Meridional do Atlântico (CRMA) tem papel fundamental na oceanografia e clima das áreas sob influência do Oceano Atlântico, controlando diretamente a estratificação e distribuição de massas d\'água, a quantidade de calor transportada pelo oceano e os ciclo e armazenamento de compostos químicos, como o CO2 em mar profundo. A formação e circulação da Água Intermediária Antártica (AIA), envolvida no transporte de calor e sal para o giro subtropical do Hemisfério Sul e nas teleconexões climáticas entre altas e baixas latitudes, é componente importante do ramo superior da CRMA. A reconstrução de propriedades de massas de água intermediárias é, portanto, importante para a compreensão dos sistemas de retroalimentação entre oceano-clima. No entanto, informações quanto a evolução da AIA continuam limitadas. Oscilações da CRMA e consequentes mudanças na distribuição de calor tem implicações importantes para o clima Sul Americano, influenciando a disponibilidade de umidade para o Sistema de Monções Sul Americano (SMSA), via temperatura da superfície marinha e posicionamento da Zona de Convergência Intertropical. Neste trabalho nós reconstruímos a assinatura isotópica da AIA durante os estágios isotópicos marinhos 2 e 3 (41-12 cal ka AP) usando isótopos de carbono e oxigênio de foraminíferos bentônicos (gêneros Cibicidoides e Uvigerina) de um testemunho de sedimentos marinhos datados por radiocarbono (1100 m de profundidade e a 20°S na costa do Brasil). Concluímos que propriedades físicas e químicas da AIA mudaram durante os estadiais Heinrich 3 e 4, provavelmente como consequência de enfraquecimento da CRMA durante estes períodos. Também reconstruímos as condições continentais do leste brasileiro entre o último máximo glacial e a deglaciação (23-12 cal ka AP) baseadas em razões Ti/Ca de nosso testemunho de sedimentos marinhos como indicadoras de aporte terrígeno do Rio Doce. A maior parte da chuva que cai na Bacia do Rio Doce está relacionada a atividade do SMAS. Nosso registro de Ti/Ca em conjunto com \'\'delta\' POT.18\'O de espeleotemas da Caverna Lapa Sem Fim, também no leste do Brasil, sugere diminuição marcante da chuva durante o interestadial Bølling-Allerød, provavelmente relacionada a enfraquecimento do SMAS. Ademais comparamos as razões de Ti/Ca com dados de saída da rodada SYNTRACE do modelo climático CCSM3 com forçantes transientes para a última deglaciação. Os registros geoquímicos e a saída do modelo mostram resultados consistentes entre si e sugerem que o leste da América do Sul passou pelo seu período mais seco de toda a última deglaciação durante o interestadial Bølling-Allerød, provavelmente relacionado ao enfraquecimento do SMAS.

Existence of solutions for p(x)-Laplacian problems on a bounded domain

In this paper we study the following p(x)-Laplacian problem: -div(a(x)&VERBAR;&DEL; u&VERBAR;(p(x)-2)&DEL; u)+b(x)&VERBAR; u&VERBAR;(p(x)-2)u = f(x, u), x ε &UOmega;, u = 0, on &PARTIAL; &UOmega;, where 1< p(1) &LE; p(x) &LE; p(2) < n, &UOmega; &SUB; R-n is a bounded domain and applying the mountain pass theorem we obtain the existence of solutions in W-0(1,p(x)) for the p(x)-Laplacian problems in the superlinear and sublinear cases. © 2004 Elsevier Inc. All rights reserved.

A class of self-stabilizing MCA learning algorithms

In this letter, we propose a class of self-stabilizing learning algorithms for minor component analysis (MCA), which includes a few well-known MCA learning algorithms. Self-stabilizing means that the sign of the weight vector length change is independent of the presented input vector. For these algorithms, rigorous global convergence proof is given and the convergence rate is also discussed. By combining the positive properties of these algorithms, a new learning algorithm is proposed which can improve the performance. Simulations are employed to confirm our theoretical results.

Real-Time Gene-Expression Extraction with Fast Classification (FC) Networks

Fast Classification (FC) networks were inspired by a biologically plausible mechanism for short term memory where learning occurs instantaneously. Both weights and the topology for an FC network are mapped directly from the training samples by using a prescriptive training scheme. Only two presentations of the training data are required to train an FC network. Compared with iterative learning algorithms such as Back-propagation (which may require many hundreds of presentations of the training data), the training of FC networks is extremely fast and learning convergence is always guaranteed. Thus FC networks may be suitable for applications where real-time classification is needed. In this paper, the FC networks are applied for the real-time extraction of gene expressions for Chlamydia microarray data. Both the classification performance and learning time of the FC networks are compared with the Multi-Layer Proceptron (MLP) networks and support-vector-machines (SVM) in the same classification task. The FC networks are shown to have extremely fast learning time and comparable classification accuracy.

A TV DIGITAL DIVULGADA NO BOLETIM ELETRÔNICO DO FNDC: UM ESTUDO SOBRE O COMPORTAMENTO DA MÍDIA NA IMPLANTAÇÃO DA TV DIGITAL NO BRASIL

Implantada no Brasil na década de 50, a TV a mídia de maior abrangência e poder ideológico entre seus públicos encara sua segunda grande transformação: ela deixa de ser analógica e passa a ser digital. Com isso, traz à tona novas possibilidades de recepção e a possível convergência de meios. Nesse contexto, o objetivo deste estudo foi analisar o processo de instalação do Sistema Brasileiro de Televisão Digital Terrestre (SBTVD-t) a partir do clipping on-line do Fórum Nacional pela Democratização da Comunicação (FNDC). A análise desse material teve como foco averiguar se o FNDC foi tendencioso ou não na veiculação de matérias voltadas aos aspectos técnicos da nova tecnologia, em detrimento de seu potencial social. Para tanto, optou-se por uma pesquisa de base quantitativa em que as informações e os dados coletados levaram à constatação de que o FNDC se mostra pouco eficaz como aparato crítico-apreciativo da grande mídia, além de não cumprir alguns de seus objetivos ao reproduzir discursos e ideologias de outros veículos. Da mesma forma, verificou-se ainda que o Governo Federal também fugiu aos objetivos listados nos decretos presidenciais que instituem e dispõem sobre a implantação do SBTVD.(AU)

Dynamics of on-line learning in radial basis function networks

On-line learning is examined for the radial basis function network, an important and practical type of neural network. The evolution of generalization error is calculated within a framework which allows the phenomena of the learning process, such as the specialization of the hidden units, to be analyzed. The distinct stages of training are elucidated, and the role of the learning rate described. The three most important stages of training, the symmetric phase, the symmetry-breaking phase, and the convergence phase, are analyzed in detail; the convergence phase analysis allows derivation of maximal and optimal learning rates. As well as finding the evolution of the mean system parameters, the variances of these parameters are derived and shown to be typically small. Finally, the analytic results are strongly confirmed by simulations.

On-line learning with adaptive back-propagation in two-layer networks

An adaptive back-propagation algorithm parameterized by an inverse temperature 1/T is studied and compared with gradient descent (standard back-propagation) for on-line learning in two-layer neural networks with an arbitrary number of hidden units. Within a statistical mechanics framework, we analyse these learning algorithms in both the symmetric and the convergence phase for finite learning rates in the case of uncorrelated teachers of similar but arbitrary length T. These analyses show that adaptive back-propagation results generally in faster training by breaking the symmetry between hidden units more efficiently and by providing faster convergence to optimal generalization than gradient descent.

The attenuation surface for contrast sensitivity has the form of a witch’s hat within the central visual field

Over the full visual field, contrast sensitivity is fairly well described by a linear decline in log sensitivity as a function of eccentricity (expressed in grating cycles). However, many psychophysical studies of spatial visual function concentrate on the central ±4.5 deg (or so) of the visual field. As the details of the variation in sensitivity have not been well documented in this region we did so for small patches of target contrast at several spatial frequencies (0.7–4 c/deg), meridians (horizontal, vertical, and oblique), orientations (horizontal, vertical, and oblique), and eccentricities (0–18 cycles). To reduce the potential effects of stimulus uncertainty, circular markers surrounded the targets. Our analysis shows that the decline in binocular log sensitivity within the central visual field is bilinear: The initial decline is steep, whereas the later decline is shallow and much closer to the classical results. The bilinear decline was approximately symmetrical in the horizontal meridian and declined most steeply in the superior visual field. Further analyses showed our results to be scale-invariant and that this property could not be predicted from cone densities. We used the results from the cardinal meridians to radially interpolate an attenuation surface with the shape of a witch's hat that provided good predictions for the results from the oblique meridians. The witch's hat provides a convenient starting point from which to build models of contrast sensitivity, including those designed to investigate signal summation and neuronal convergence of the image contrast signal. Finally, we provide Matlab code for constructing the witch's hat.

Competition for shortest paths on sparse graphs

Optimal paths connecting randomly selected network nodes and fixed routers are studied analytically in the presence of a nonlinear overlap cost that penalizes congestion. Routing becomes more difficult as the number of selected nodes increases and exhibits ergodicity breaking in the case of multiple routers. The ground state of such systems reveals nonmonotonic complex behaviors in average path length and algorithmic convergence, depending on the network topology, and densities of communicating nodes and routers. A distributed linearly scalable routing algorithm is also devised. © 2012 American Physical Society.

Seizure detection in subdural recordings using nonlinear decision functions

This dissertation proposed a new approach to seizure detection in intracranial EEG recordings using nonlinear decision functions. It implemented well-established features that were designed to deal with complex signals such as brain recordings, and proposed a 2-D domain of analysis. Since the features considered assume both the time and frequency domains, the analysis was carried out both temporally and as a function of different frequency ranges in order to ascertain those measures that were most suitable for seizure detection. In retrospect, this study established a generalized approach to seizure detection that works across several features and across patients. ^ Clinical experiments involved 8 patients with intractable seizures that were evaluated for potential surgical interventions. A total of 35 iEEG data files collected were used in a training phase to ascertain the reliability of the formulated features. The remaining 69 iEEG data files were then used in the testing phase. ^ The testing phase revealed that the correlation sum is the feature that performed best across all patients with a sensitivity of 92% and an accuracy of 99%. The second best feature was the gamma power with a sensitivity of 92% and an accuracy of 96%. In the frequency domain, all of the 5 other spectral bands considered, revealed mixed results in terms of low sensitivity in some frequency bands and low accuracy in other frequency bands, which is expected given that the dominant frequencies in iEEG are those of the gamma band. In the time domain, other features which included mobility, complexity, and activity, all performed very well with an average a sensitivity of 80.3% and an accuracy of 95%. ^ The computational requirement needed for these nonlinear decision functions to be generated in the training phase was extremely long. It was determined that when the duration dimension was rescaled, the results improved and the convergence rates of the nonlinear decision functions were reduced dramatically by more than a 100 fold. Through this rescaling, the sensitivity of the correlation sum improved to 100% and the sensitivity of the gamma power to 97%, which meant that there were even less false negatives and false positives detected. ^

Turkish-American relations in the post-Cold War era, 1990-2005

This study examines the contours of Turkish-American foreign relations in the post-Cold War era from 1990 to 2005. While providing an interpretive analysis, the study highlights elements of continuity and change and of convergence and divergence in the relationship between Ankara and Washington. Turkey’s encounter with its Kurdish problem at home intertwined with the emergence of an autonomous Kurdish authority in northern Iraq after the Gulf War that left a political vacuum in the region. The main argument of this dissertation is that the Kurdish question has been the central element in shaping and redefining the nature and scope of Turkish-American relations since 1991. This study finds that systemic factors primarily prevail in the early years of the post-Cold War Turkish-American relations, as had been the case during the Cold War era. However, the Turkish parliament’s rejection of the deployment of the U.S. troops in Turkey for the invasion of Iraq in 2003 could not be explained by the primacy of distribution of capabilities in the system. Instead, the role of identity, ideology, norms, and the socialization of agency through interaction and language must be considered. The Justice and Development Party’s ascension to power in 2002 magnified a wider transformation in domestic and foreign politics and reflected changes in Turkey’s own self-perception and the definition of its core interests towards the United States.

Aplicação do exame da proporcionalidade diante da implantação de empreendimentos eólicos em áreas de preservação permanente

The setting up of wind power enterprises at Permanent Preservation Areas reflects the obvious conflict and necessary convergence between free market and energy security on the one hand, and the promotion of environmental quality on the other. From the perspective of energy sustainability, and in order to achieve development (in its complex meaning, which converges economic, social, environmental and cultural aspects), the harmonization between free market and an ecologically sustainable environment is required. This work aims to identify the link between the protection system of the Permanent Preservation Areas and the current constitutional order, by analyzing the implementation of wind power enterprises in these protected zones focusing on the proportionality aspects. A legal and purposeful research was developed, from a theoretical method, followed by collecting and analyzing both primary and secondary data. From these data, the law, the legal literature and judicial decisions were cross-examined, under the light of the Constitution and guided by the theory of proportionality and related development imperatives. In this context, the present study identified the link between the principles of the economic order, environment and energy law, finding their basis under the Federal Constitution and development. By reproducing this interrelationship and by means of post-crisis institutional reforms, the guiding objectives of the Brazilian electric sector began to corroborate the precepts of development, although issues regarding its sustainability still persist. The appraisal of proportionality indicates that the Permanent Preservation Areas protection system is insufficient to materialize the right to a healthy quality of life upon the implementation of wind projects at Permanent Preservation Areas, albeit seeking the harmonization between free market and environmental protection.