Band Offset
Mostrando 1-11 de 11 artigos, teses e dissertações.
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1. Low-Overhead Low-Complexity Carrier Phase Recovery Technique for Coherent Multi-Band OFDM-Based Superchannel Systems Enabled by Optical Frequency Combs
Abstract In this paper, we have designed a low-overhead low-complexity carrier phase tracking scheme for OFDM-based superchannel transmission system enabled by optical frequency combs. In this scheme, taking advantage of the broadband phase coherence provided by optical frequency combs among the OFDM-bands, the carrier phase retrieved from pilot-subcarriers
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2021-03
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2. Electrical and optical numerical modeling of DP-PPV based polymer light emitting diode
Abstract In this paper, an in-depth study of the electrical and optical characteristics of Polymer Light Emitting Diodes ITO/PEDOT: PSS/DP-PPV derivatives/Al(Ca) is presented. Three polymer materials are considered; poly(2,3-diphenyl-5-(4-heptyloxy-4'-oxytrimethylenediphenyl)-phenylenevinylene) (P1), poly(2,3-diphenyl-5-[4-(4-pentylcyclohexyl)phenoxy]-propyl
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2018-06
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3. A microwave method for complex permittivity extraction of thin materials
An improved microwave method to extract the complex permittivity of solid and liquid materials filled in a short-circuited waveguide is developed. The method determines accurately the dielectric constant of thin and moderate thick samples. It eliminates the problems arising from any position offset of the dielectric slab in transmission / reflection methods.
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2012-12
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4. Cálculos de estrutura eletrônica de materiais e nanoestruturas com inclusão de autoenergia: Método LDA - 1/2. / Electronic structure calculations of material and nanostructures with the inclusion of the self-energy: the LDA - 1/2 method.
Neste trabalho, utilizamos o desenvolvimento recente do método DFT/LDA-1/2 para cálculos de estados excitados em materiais. Começamos com um resumo da teoria do funcional da densidade (DFT) e incluímos uma introdução ao método LDA-1/2 para cálculos de excitações em sólidos. Na compilação dos resultados esperamos ter demonstrado a utilidade do LD
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 13/12/2011
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5. Evaluation of the data produced by the s band weather radars network located in central southern Brazil / Avaliação dos dados produzidos pela rede de radares meteorológicos de banda "S" localizados no centro sul do Brasil
Data from the weather radars located in central, southeastern and southern Brazil has been used by the CPTEC and DECEA since the agreement between both institutions was signed in 2004. Before this date the radar data was used by flight protection purposes only, and was not stored. Nowadays, the radar products derived from the scanning strategy of all radars
Publicado em: 2007
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6. Growth and structural characterization of PbTe/PbEuTe double barrier
A series of PbTe/PbEuTe double barrier samples with different barrier widths were successfully grown on BaF2 substrates by molecular beam epitaxy. The electron concentration of PbTe spacer and well layers was controlled by the deviation from stoichiometry, while the buffer and cap layers were intentionally doped with bismuth to obtain low-resistivity layers
Brazilian Journal of Physics. Publicado em: 2006-06
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7. Estruturas de barreira dupla de PbTe/PbEuTe crescidas por epitaxia de feixe molecular / PbTe/PbEuTe double barrier structures grown by molecular beam epitaxy
This work reports the growth of PbTe/Pb(1-x)Eu(x)Te double barrier (DB) structures by molecular beam epitaxial and the device processing aiming the resonant tunneling measurement. The samples were grown on (111) BaF(2) substrates at 300°C. Resistivity and Hall effect measurements were performed on reference films to determine the most suitable electrical pr
Publicado em: 2006
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8. Design of distributed microwave oscillators with reverse feedback. / Projeto de osciladores de microondas distribuídos com realimentação reversa.
In this dissertation, a design methodology applied to microwave reverse feedback distributed voltage controlled oscillators - DVCO - is proposed. This circuit constitutes a new class of oscillators, obtained from reverse feeding back of the distributed amplifier. The main advantage of this topology is its capacity to achieve ultra-wideband frequency tuning.
Publicado em: 2005
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9. Estudos de hetero-estruturas de camadas tensionadas de InGaAs/GaAs
We present a detailed study of InxGa1-xAs/GaAs strained-layer single quantum well and superlattices. The strain in each type of layer in the superlattices was determined from the Raman measurements. We determined the energy difference between the confined states of electrons in the conduction band and the strain-split heavy and light holes in the valence ban
Publicado em: 1988
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10. Some aspects of the pathophysiology of homozygous Hb CC erythrocytes.
We have studied erythrocytes from homozygous CC patients in vitro and in perfused rat mesoappendix vasculature to answer some long-standing questions. By examination of wet whole blood preparations, and by comparing the cell distribution on isopycnic continuous density gradients of whole blood samples from a splenectomized CC patient with those from three in
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11. Effects of Dopamine Depletion on Network Entropy in the External Globus Pallidus
Dopamine depletion in cortical-basal ganglia circuits in Parkinson's disease (PD) grossly disturbs movement and cognition. Classic models relate Parkinsonian dysfunction to changes in firing rates of basal ganglia neurons. However, disturbances in other dynamics of neural activity are also common. Taking both inappropriate firing rates and other dynamics int
American Physiological Society.