Quantum Communications
Mostrando 1-10 de 10 artigos, teses e dissertações.
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1. O peso das palavras, o choque dos ideais: uma análise crítica dos indicadores de sustentabilidade como critérios para a gestão da comunicação organizacional / The weight of words, the clash of ideals: a critical analysis of Indicators of Sustainability criteria for the management of Organizational Communication.
A new world order is demanding effectively differentiated postures, organizations from all sectors and spheres, accompanied by the growing surveillance society through mechanisms for evaluating their activities. In order to define ethical parameters have been and are being developed models of accountability of corporate activities. Through them, it is intend
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 23/03/2011
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2. RECURSOS PRÁTICOS PARA COMUNICAÇÕES QUÂNTICAS EM FIBRAS ÓPTICAS / PRACTICAL ASSETS FOR FIBER OPTICAL QUANTUM COMMUNICATIONS
As comunicações quânticas estão rapidamente integrando-se às redes de fibras ópticas, entretanto muitos desafios de engenharia ainda existem para essa aglutinação. Esta tese discute algumas soluções práticas para a melhoria de aplicações reais em comunicações quânticas em fibras ópticas. No primeiro experimento uma fonte de pares de fótons
Publicado em: 2009
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3. POLARIZATION OF LIGHT CONTROL IN MONOMODE OPTICAL FIBERS AND APLICATIONS / CONTROLE DA POLARIZAÇÃO DA LUZ EM FIBRAS ÓPTICAS MONOMODO E APLICAÇÕES
The control of polarization state, as well as a control of all states of polarization of a light signal travelling through a singlemode optical fiber, is performed using different schemes. The polarization control of the signal in a DWDM channel is performed using reference signals in lateral channels in real time. A polarization encoded quantum key distribu
Publicado em: 2009
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4. Criptografia quântica em redes de informação crítica - aplicação a telecomunicações aeronáuticas. / Quantum cryptography in critical information networks - application to aeronautical telecommunications.
The importance of security maintenance in critical information networks has been rising in recent times. Over the past decades, the utilization of cryptography tools, mainly those based on computationally intractable problems, was enough to ensure the security of communications systems. The development of the new information processing technique known as qua
Publicado em: 2008
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5. SINGLE PHOTON COUNTING IN THE NEAR- AND MID-INFRARED VIA FREQUENCY UP-CONVERSION APPLIED TO QUANTUM COMMUNICATIONS / CONTAGEM DE FÓTONS NO INFRAVERMELHO PRÓXIMO E MÉDIO VIA CONVERSÃO DE FREQÜÊNCIAS APLICADA A COMUNICAÇÕES QUÂNTICAS
Two single photon counting devices, operating at near- and mid-infrared wavelengths, are introduced and experimentally investigated. Both use a twostage technique, comprised of an initial frequency up-conversion procedure inside a nonlinear crystal followed by a silicon avalanche photodiode. Whereas the first project consists on detection of single photons a
Publicado em: 2007
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6. Teoria e implementaÃÃo de detectores de fÃtons isolados para comunicaÃÃes quÃnticas em redes Ãpticas / Theory and implementation of sigle-photon detectors for quantum communications in optical networks
Tecnologia da InformaÃÃo QuÃntica à uma Ãrea multidisciplinar nova que tem recebido muita atenÃÃo por ser promissora e devido a seu alto potencial em resolver problemas ainda nÃo solucionados. Dentro desta grande Ãrea, as ComunicaÃÃes QuÃnticas estÃo bastante desenvolvidas. Nesta sub-Ãrea, distribuiÃÃo QuÃntica de Chaves à o campo mais avan
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 13/06/2006
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7. ESQUEMAS DE MODULAÇÃO PARA DISTRIBUIÇÃO QUÂNTICA DE CHAVES COM CODIFICAÇÃO DE FREQÜÊNCIA / MODULATION SCHEMES FOR FREQUENCY CODED QUANTUM KEY DISTRIBUTION
Quantum cryptography has been proposed as a solution to the cryptographic key distribution problem with absolute security guaranteed by the principles of quantum mechanics. Through this scheme it is possible to find out whether a spy tried to eavesdrop on the transmission, which was impossible to discover using classical transmission techniques. In this work
Publicado em: 2005
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8. Fibras opticas de vidros teluritos de tungstenio para amplificação de grande largura de banda / Fibras opticas de vidros teluritos de tungstenio para amplificação de grande largura de banda
In optical communications, high capacity information transmission systems demand broadband optical amplifiers. Therefore, it has become increasingly necessary to manufacture devices with such characteristics. Optical amplifier devices based on Tellurite glasses are ideal for manufacturing broadband optical amplifiers. In the last few decades, most researcher
Publicado em: 2005
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9. Obtenção e caracterização de materiais dopados SiO2-CdSe a partir de sonogeis de silica
The sol-gel process has proved to be extremely interesting in the production of new materiaIs. This is clearly indicated by the great number of publications in this area in the last decade. The possibility of obtaining monolithic solid materials and also powders, films and fibers from a liquid mixture of components at room temperature via aggregation and pol
Publicado em: 1994
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10. Analytical description of the activation of multi-state receptors by continuous neurotransmitter signals at brain synapses.
Chemical synaptic transmission is a fundamental component of interneuronal communications in the central nervous system (CNS). Discharge of a presynaptic vesicle containing a few thousand molecules (a quantum) of neurotransmitter into the synaptic cleft generates a transmitter concentration signal that drives postsynaptic ion-channel receptors. These recepto