On communication policies

RAMOS, Murilo; SANTOS, Suzy dos (2007). Políticas de comunicação: buscas teóricas e práticas. São Paulo: Paulus. 406 p. On communication policies — Divided into theoretical formulations and analyses of communication practices, this book offers a collection of pertinent articles for a debate on Brazil’s communication policies. There are provocative and current issues broached by different authors, such as a rediscussion of the concept of civil society, an analysis of the asymmetry between the opposite poles of reception and consumption of televised messages, and a survey of today’s communication market in Brazil

Threatened, the public communication is vital to democracy

Given the threats of political and social retrogressions in Brazil, including the policy of dismantling the TV Brasil and the Empresa Brasil de Comunicação (EBC), this note discusses how is important the public communication to democratic societies. Historical and conceptual references as well as the relations between the state and communication are the starting point for the analysis. It deals with the inherent relation between public communication and the communication rights and its centrality in the public nature of governmental institutions. Based on the model of public communication developed in Western Europe, this note shows that EBC represents a milestone in the Brazilian public communication history and gives examples of its recent trajectory indicating that it was more and more integrated into national society

TV, um poder sem controle

O artigo tem como tema central a relação TV e sociedade. Ele trata da televisão como um fenômeno social, apresenta as linhas básicas do modelo público europeu de broadcasting e analisa o caso brasileiro no momento atual. O texto situa historicamente o surgimento e a consolidação da TV como veículo de comunicação de massa e, a partir daí, analisa a questão do controle e do financiamento das emissoras. Questiona o modelo comercial hegemônico adotado no Brasil, ao confrontá-lo com o sistema público europeu. Mostra como a televisão, em nosso país, torna-se um poder autônomo sem qualquer controle social e apresenta um breve balanço das reações da sociedade à atual crise de qualidade da TV brasileira.The relation between TV and society is the central subject of this paper. It examines the television like a social phenomenon, it shows the basic lines of European public model of broadcasting and analyses the Brazilian case in the actual moment. The paper treats the birth and consolidation of TV like mass communication vehicle and analyses its control and financing. It compares the hegemony commercial model used in Brazil with the European public system. It shows how Brazilian television gives a autonomous power, without any social control and it makes a brief balance about the public reaction face the actual crises of quality in the Brazilian television

Ética, rendición de cuentas en los medios de comunicación y sus contenidos aplicados al Servicio de Defensoría de la empresa Brasil de Comunicación

El texto busca analizar y promover parámetros éticos para el servicio de Defensor de los oyentes, considerando la experiencia del Defensor en la EBC, la empresa pública de comunicación envuelta con el pluralismo en Brasil. La EBC es compuesta por una televisión pública, ocho estaciones de radio y una agencia de noticias. Su público puede enviar sus críticas, elogios y quejas para la Defensoría. La experiencia de Defensoría puede ser considerada una práctica de rendición de cuentas. Su tarea es asegurar que el contenido transmitido siga los principios éticos establecidos. Los autores hicieron una revisión de la literatura y analizaron los mensajes encaminados entre 2008 y 2010. Ellos entienden que el desempeño de la Defensoría proviene visibilidad y transparencia a los errores y dilemas asociadas con las funciones de los medios, trayendo más credibilidad y dialogo con el público, y encorajando una cultura de rendición de cuentas entre los profesionales. Los investigadores revisaron los documentos éticos y percataron la importancia del canal de mediación, que proviene visibilidad por intermedio del programa semanal. La iniciativa promueve un ejercicio de disciplina y cuidado por parte de los profesionales y el público de la Empresa Pública de Comunicación.This paper goal is to analysis and provide ethics parameters for Radio Ombudsman services, considering the experience of the Ombudsman at the EBC, it is a public company engaged with the pluralism in Brazil. The organization is composed by the Public TV, eight radio stations, and a news agency. Its audience can rely on the Ombudsman service as a direct channel for criticism, reviews and complaints. The Ombudsman experience may be considered a Media Accountability System. Its task is to assure that the broadcast content will follow ethical principles established. 674 The authors accomplished a literature review and analyzed emails sent between 2008 and 2010. They find that the ombudsmen performance provides visibility and transparency to errors, issues and dilemmas associated with the media functions, stimulating more credibility, prompt discussion with public, and encourages a culture of greater accountability in the newsroom. From the review of ethical documents, also, they came across with the fact that the EBC Ombudsman sought to be a mediation channel that provides visibility to matters raised up during a weekly program. The initiative can also inscreasily promote an exercise of discipline and care on the part of public communication institutions and its professionals

Iron ore minerals depression: influence of mineralogy, morphology, and conditioning pH

Nove amostras de minerais de ferro, provenientes de diferentes minas (jazidas) pertencentes à Vale, foram o objeto desse trabalho, que buscou correlacionar a depressão das referidas amostras com amido e carboximetil celulose versus parâmetros mineralógicos e morfológicos. O amido de milho convencional se mostrou capaz de realizar ação depressora sobre todas as amostras, exceto sobre aquelas que se mostraram mais ricas em hematita compacta (HC). Tais hematitas podem ser chamadas de "problemáticas", visto que interagem fortemente com o coletor e apresentam deficiência de serem deprimidas pelo amido, exigindo elevadas dosagens para minimização de sua tendência à flotação. Carboximetil celulose não apresentou ação depressora sobre nenhuma das amostras estudadas. A flotabilidade das amostras ricas em HC pode ser minimizada pela ação do amido de milho condicionado em pH 8,0-8,5. Testes de flotação com minério itabirítico, contendo elevado percentual de hematitas compactas de pequeno tamanho de cristal, confirmaram a redução do teor de Fe no rejeito com a utilização de amido condicionado em pH≅8.Nine samples of Fe-bearing minerals from several mines of Vale were the object of this work, which aimed to make a correlation between mineralogy and morphology versus flotation depression by starch and carboxy methyl cellulose. They did not demand strong action from depressants. Cornstarch was able to depress all the samples, except those that exhibited high HC content. The latter samples could be regarded as “problematic” because they were able to interact strongly with collector and demanded a high dosage of depressant to accomplish full depression. Carboxy methylcellulose did not show depressive action on any of the studied Febearing minerals. Flotation response of the samples, which are rich in HC, could be minimized by the action of starch conditioned at pH 8.0-8.5, increasing Fe recovery in the process

Process Evaluation of an Iron Ore Operation Using the Floatability Component Model

The Brucutu iron ore mine (Minas Gerais, Brazil) is Vale‘s largest iron producing operation achieving around 21 million tons per annum. Evaluation of flotation performance is of high importance as even small gains can lead to large monetary benefits. Cell-by-cell samples of the froth products, selected feed and pulp-products were analyzed for flow rate, particle size distribution and chemical composition. In addition, certain samples were analyzed on an assay-by-size basis and hydrodynamic measurements of certain flotation cells were also performed. This detailed experimental dataset was then used to calibrate a floatability component model of the process. Longer mainline residence time resulted in significant Fe2O3 losses while yielding little benefit in terms of SiO2 product grade. Scavenger 2 has twice the residence time of scavenger 1 while having to treat only 10% of the SiO2, resulting in high Fe2O3 recoveries to the froth and poor separation. In addition, it is shown that the Fe2O3 exhibits true flotation behavior resulting in increased Fe2O3 losses. Simulations using the floatability component model identified avenues of process improvement to address the identified behavior. The insight provided by the simulations into the dynamics of the flotation process is invaluable for process engineers

Air dispersion parameters in mechanical flotation cells of industrial Brazilian plants

O objetivo desse trabalho é apresentar e discutir a determinação dos parâmetros de dispersão de ar em células mecânicas de flotação, em circuitos industriais brasileiros. Foram investigados os circuitos rougher e scavenger das usinas RPM, Taquari-Vassouras, Copebras e Fosfértil-Catalão (atual Vale Fertilizantes). Nas usinas RPM e Taquari-Vassouras, foram determinados a velocidade superficial do ar (Jg), o hold-up do ar (εg), o diâmetro médio de bolhas (d32) e o fluxo de área superficial de bolhas (Sb). Para as outras usinas, foram determinados somente o Jg e εg. Os resultados mostraram que, com exceção da RPM, todos os circuitos investigados apresentaram baixos valores para os parâmetros de dispersão do ar. Taquari-Vassouras apresentou os mais baixos valores médios para Jg e εg, respectivamente, 0,05 cm/s e 5%. Os maiores valores de Jg foram determinados no circuito rougher da Copebras, 1,17 cm/s, ao passo que a RPM apresentou os maiores valores para o hold-up e tamanho de bolha, respectivamente, 31% e 2,61mm. Os valores obtidos, para Sb, situaram-se abaixo daqueles reportados na literatura.The aim of this paper is to present and discuss the air dispersion parameters determined for industrial Brazilian flotation circuits. The rougher and scavenger circuits of RPM, Taquari-Vassouras, Copebras and Fosfertil-Catalao (today Vale Fertilizantes) were investigated. For RPM and Taquari-Vassouras, the superficial gas velocity (Jg), gas hold-up (epsilon(g)), bubble size diameter (d(32)) and superficial area bubble flux (S-b) were measured, whereas only the J(g) and epsilon(g) were measured in the other circuits. The results pointed out that, except for RPM, all the circuits presented very low values for the air dispersion parameters. Taquari-Vassouras presented the lowest values for average J(g) and gas hold-up: 0.05 cm/s and 5%, respectively. The highest J(g) value was presented for the rougher circuit of Copebras, 1.17cm/s, while RPM presented the highest values for epsilon(g) and bubble size, respectively 31% and 2.61mm. In the circuits where the calculation of the S-b parameter was possible, the results obtained lay in a range lower than those reported in literature

Curvas de forças entre hematita e quartzo por afm e seu efeito na seletividade do processo de flotação de minério de ferro / Force curves between hematite and quartz by afm and their effect on the selectivity of the iron ore flotation process

Medidas de força de interação entre uma ponta funcionalizada com quartzo e superfícies de hematita e quartzo, em meio líquido (soluções de eletrólito indiferente, amido de milho gelatinizado e mistura de amido de milho gelatinizado e eteramina) foram realizadas utilizando a técnica de microscopia de força atômica. Essas medidas foram ainda comparadas com os estudos de potencial zeta de partículas de quartzo e hematita em função do pH. As curvas de interação entre a ponta funcionalizada de quartzo e a superfície de hematita mostraram forças repulsivas em eletrólito e em pH=10,5. Na presença de amido, a curva de força começa a apresentar uma interação atrativa, que pode ser devido à uma diminuição da repulsão da dupla camada elétrica. As forças de interação entre as superfícies de quartzo (superfície e ponta) foram repulsivas na presença de amido de milho, mostrando que as moléculas de amido não interagem com a superfície do quartzo. De fato, os valores de potencial zeta foram negativos tanto na presença como na ausência de amido. A interação entre ponta funcionalizada de quartzo e a superfície de hematita, na presença da mistura de reagentes, revelou também uma pequena atração a curtas distâncias demonstrando que pode ocorrer uma heterocoagulação