135 resultados para Ruído (Telecom)


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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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The restructuring of the state productive sector of the central government of China is a phenomenon that has occurred since 1978, and is not yet complete. In a centrally planned economy, China's government introduced a series of economic and social transformations in order to modernize the country's economic structure. The flagship of these reforms was the reintroduction of a market economy, living side by side with a strong state control over key economic variables of the country. In this process, there was a restructuring of ownership of enterprises by means of collectivization, the creation of joint stock companies, establishing joint ventures with foreign companies or privatization. The result of this process was the creation of a set of holding companies that operate in strategic sectors of China's economy such as energy, transport, telecom, capital goods and defense. Within this brief article we will focus on the process of opening up and modernization as the expression of a national project that sought to understand the changes in the international economy and sought to adapt the demographic characteristics of China and productive so you get the best out of globalization.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Esta pesquisa analisou as diversas soluções para atenuar os níveis de ruído dos tratores e propor um projeto de redução do ruído na sua fonte. Para tal, se propôs projetar, executar e testar alterações em componentes mecânicos causadores de ruído nos tratores, fazendo com que esses níveis se enquadrem em valores considerados salubres. Todas alterações e ensaios foram executados num trator Massey Ferguson MF 290. Para a redução do ruído foram atacados as 3 fontes principais de ruído do trator : o sistema de exaustão de gases, a hélice do sistema de arrefecimento e o sistema de admissão de ar. Como conclusão final pode-se afirmar que é possível atenuar o ruído de tratores agrícolas até níveis salubres (que não causem perda de audição a seus operadores), atuando-se exclusivamente nas fontes de ruído (motor e seus acessórios).

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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A novel AC Biosusceptometry (ACB) system with thirteen sensors it was implemented and characterized in vitro using magnetic phantoms. The system presenting coils in a coaxial arrangement with one pair of excitation coil outside and thirteen pairs of detection coils inside. A first-order gradiometric configuration was utilized for optimal detection of magnetic signals. Several physical parameters such as baseline, number of turns, excitation field and diameters were studied for improvement of the signal/noise ratio. This system exhibits an enhanced sensitivity and spatial resolution, due to the higher density of sensors/area. In the future those characteristics will turn possible to obtain images of magnetic marker or tracer in the gastrointestinal tract focusing on physiological and pharmaceutical studies. ACB emerged due to its interesting nature, noninvasiveness and low cost to investigate gastrointestinal parameters and this system can contribute for more accurate interpretation of biomedical signals and images

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Almost forty years computed tomography (CT) has been one of the most powerful tools in diagnostic imaging. However, this modality delivers relatively high doses to their patients. It is known that the inappropriate use and unnecessary radiation may be associated with a significant risk of cancer, especially in pediatric patients. Moreover, the quality assurance in CT, provided and required by Portaria 453/98 and the guide of the RE 1016/05, ensures that the images generated by computer tomography provide reliable diagnostic information with doses as low as reasonably achievable. This research aimed to make the quality control (QC) of CT equipment; establish a better relationship between dose and noise on the image to protocols of skull CT according to the study of optimization proposed in 2005 by Daros; and assess the dose distribution in different cranial organs for protocols of adult and pediatric use in the routine of the Department of Diagnostic Imaging of HCFMB-UNESP. The equipment used for testing QC, optimization and dosimetry was a third generation tomograph GE Sytec 3000i

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The best way to detect breast cancer is by screening mammography. The mammography equipments are dedicated and require a rigorous quality control in order to have a good quality image and to early detect this disease. The digital equipment is relatively new in the market and there isn’t a national rule for quality control for several types of digital detectors. This study has proposed to compare two different tests manuals for quality control provided by the manufacturers of digital mammography equipments, and also compare them to the “European guidelines for quality assurance in breast cancer screening and diagnosis “(2006). The studied equipments were: Senographe 2000D from General Electric (GE) and the Hologic Selenia Lorad. Both were digital mammography equipments, the GE unit presents an indirect digital system and the other presents a direct digital system. Physical parameters of the image have been studied, such as spatial resolution, contrast resolution, noise, signal-tonoise ratio, contrast-to-noise ratio and modulation transfer function. After that, a study of the importance of quality control and the requirement to implement a Quality Assurance Program has been done. One data collection was done to compare those manual, it was done by checking which tests are indicated and the minimum frequency which they should be conducted in accordance with each manufacturer. The tests were performed by different methodologies and the results were compared. The examined tests were: the breast entrance skin dose, mean glandular dose, contrast-to-noise ratio, signal-to-noise ratio, automatic exposure control and automatic control of density, modulation transfer function, equipment resolution, homogeneity and ghost

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In this work, it is presented a novel method for calculating some intrinsic parameters such as capture mean time, thermic emission mean time, capture probability and noise gain on quantum well infrared photodetectors. Such devices are built by depositing layers of semiconductors of different energy gap, forming quantum wells. The present method uses rate equations to describe the occupation of discrete states of the quantum wells, that together with noise gain equations given in literature, are solved self consistently. The input data of the method is experimental measurement of dark current (current measured with no relevant incident photon) versus applied bias. In order to validate this approach, the values obtained were compared with results from literature

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O joão-porca (Lochmias nematura) é uma ave pertencente à família Furnariidae. Tem coloração predominantemente marrom, com pintas brancas em seu peito e ventre, sua cauda é preta e apresenta o supercílio branco. Habita a margem de córregos e riachos, evitando áreas com maior intensidade de luz. Seu canto é um trinado agudo e forte, que tende a suplantar o ruído gerado pela movimentação da água nesses ambientes. Seu nome popular é decorrente de seus hábitos alimentares: caça artrópodes na margem dos corpos d’água e em poças lamacentas e lodosas. Sua dieta e seu comportamento de caça são pouco conhecidos, o que impulsionou a realização deste estudo. Para tanto realizamos buscas ativas por indivíduos desta espécie ao longo de leitos na Serra do Japi, município de Jundiaí, no entorno da Floresta Estadual Edmundo Navarro de Andrade e no Sítio Esperança, município de Rio Claro. Estes locais foram escolhidos devido à facilidade de detecção da espécie. Para tornar as anotações em campo mais rápidas foram utilizadas planilhas com os parâmetros a serem analisados. Os parâmetros analisados foram manobra de captura, manipulação, item alimentar, tamanho em relação ao bicho da ave, distância da margem ao local de captura, substrato de captura e as características principais do substrato e do corpo d’água. Somando-se a isso foram levantadas todas as fotografias postadas no site WikiAves (www.wikiaves.com.br) que mostrassem Lochmias nematura com presas em seu bico, obtendo-se uma dieta mais completa. Isto mostrou que a dieta da espécie é muito mais diversificada do que o previsto pela literatura aferido através da dissecção estomacal. Seus principais itens alimentares são aranhas, oligoquetos, decápodes, larvas de tricópteros, larvas de odonatos, coleópteros, formigas, girinos e até mesmo anuros adultos... (Resumo completo, clicar acesso eletrônico abaixo)

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Work organized in shifts, either for technological, social or economic imposition, allows the best use of means of production, increasing the overall productivity of the enterprises. At the same time, this type of work harms the individual productive capacity of workers, particularly those involved in the night shift. The objective of this work was to assess the behaviour of production in a continuous line and subjected to work organized in shifts. Through the statistical method of analysis of variance, Spearman's test and Tukey's method, was analysed the distribution of the productivity index measured in three fixed shifts of work in a glass company. The productivity index, provided by the integrated management system of the company, refers to the ratio of actual productivity to total productivity. The statistical analysis shows that factors of production, such as allocation of workers, do not interfere with productivity, showing an unexpected pattern, where the average productivity for the three shifts are close and the correlation between the number of workers on the line and productivity is low. The conditions of production had an adverse work environment with exposure to noise, heat, vaporized mist of lubricating oil and risk of accidents. The findings show that the calculation of productivity in use is limited and its use in company’s production control may produce distortions. It is proposed to examine alternative calculations methods that consider the overall productivity

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A partir de uma seleção de dezesseis poemas metalinguísticos dos livros Liturgia da Matéria (1982), Mínima Lírica (1989), Trovar Claro (1997), Macau (2003), Tarde (2007) e Formas do Nada (2012) pretendeu-se chegar ao que se chama aqui de A Poética de Paulo Henriques Britto. Tal poética compreende as características e temas mais frequentes em sua poesia, bem como quais recursos expressivos são mais evidentes em cada um dos livros. Paulo Henriques Britto, tradutor, professor e escritor com sete livros publicados (sendo um deles de contos), lançou seu primeiro livro de poesias, Liturgia da Matéria, em 1982 e vem ganhando destaque no cenário da poesia brasileira contemporânea. Em 2004 ganhou um dos maiores prêmios literários do Brasil, o Prêmio Portugal Telecom, com o livro Macau lançado em 2003. Pretende-se que o estudo aqui feito acerca da poesia de Britto não fique restrito a si, mas que traga contribuições para a crítica da poesia brasileira contemporânea, já que ainda se carece de uma quantidade de material critico relevante, o que muitas vezes dificulta o ensino e a aprendizagem de tal poesia. Assim, a análise da poesia metalinguística de Paulo Henriques Britto pretende descobrir, em parte, quais os novos rumos que a produção de poesia tomou no Brasil. Nosso corpus é composto por dezesseis poemas, sendo eles: “I”, da série “Dez Sonetos Sentimentais”, “III”, da série “Três Lamentos” e “Profissão de Fé” do livro Liturgia da Matéria; “I” e “II”, da série “Minima Poética” do livro Mínima Lírica; “II” e “VII” da série “Sete Estudos para a Mão Esquerda” e “Sonetilho de Verão” do livro Trovar Claro; “II” da série “Fisiologia da Composição” e “Biodiversidade” do livro Macau; “I” e “II” da série “Art Poétique” e “5” da série “Crepuscular” do livro Tarde e “I” e “III” da série “Oficina” e o poema “Pós” do ...