Search results for " Modulation"

showing 6 items of 496 documents

Heart rate variability in chronic and acute stress : with special reference to nocturnal sleep and acute challenges after awakening

2011

sykeuniawakening responsekestävyysharjoittelustressihormonitfyysinen kuormittavuusstressovertrainingendurance trainingstress hormonescardiovascular autonomic modulationpsyykkinen kuormittavuusylikuntoautonominen hermostovaihteluurheilijat
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Theoretical and Experimental Study of Polarization Modulation Instability in All-Normal Dispersion Photonic Crystal Fibers

2018

Experimental observation of polarization modulation instability in all-normal dispersion photonic crystal fibers is reported. Stokes and anti-Stokes sidebands with spectral shift of 40 nm were observed when the fiber was pumped at 1064 nm. Experimental results are baked by a vectorial four-wave mixing model.

symbols.namesakeFour-wave mixingMaterials sciencesymbolsPhysics::OpticsPolarization modulationSpectral shiftSelf-phase modulationPolarization (waves)InstabilityMolecular physicsRaman scatteringPhotonic-crystal fiberLatin America Optics and Photonics Conference
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An Improved Method for Estimating the Time ACF of a Sum of Complex Plane Waves

2010

Time averaging is a well-known technique for evaluating the temporal autocorrelation function (ACF) from a sample function of a stochastic process. For stochastic processes that can be modelled as a sum of plane waves, it is shown that the ACF obtained by time averaging can be expressed as a sum of auto-terms (ATs) and cross-terms (CTs). The ATs result from the autocorrelation of the individual plane waves, while the CTs are due to the cross-correlation between different plane wave components. The CTs cause an estimation error of the ACF. This estimation error increases as the observation time decreases. For the practically important case that the observation time interval is limited, we pr…

symbols.namesakeMathematical optimizationFourier transformStochastic processKernel (statistics)AutocorrelationMathematical analysisPlane wavesymbolsInterval (mathematics)Frequency modulationComplex planeMathematics2010 IEEE Global Telecommunications Conference GLOBECOM 2010
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The interplay between the host microbiome and pathogenic viral infections

2021

The microorganisms associated with an organism, the microbiome, have a strong and wide impact in their host biology. In particular, the microbiome modulates both the host defense responses and immunity, thus influencing the fate of infections by pathogens. Indeed, this immune modulation and/or interaction with pathogenic viruses can be essential to define the outcome of viral infections. Understanding the interplay between the microbiome and pathogenic viruses opens future venues to fight viral infections and enhance the efficacy of antiviral therapies. An increasing number of researchers are focusing on microbiome-virus interactions, studying diverse combinations of microbial communities, …

virusesBiologyBacterial Physiological PhenomenaMicrobiologyViral infectionhost-microbiome interactionsInterferonImmunityVirologymedicineAnimalsHumansMicrobiomeOrganismhost-virus interactionsimmune modulationBacteriaHost (biology)pathogenesisMicrobiotainterferonImmune modulationQR1-502antiviral treatmentsVirus DiseasesImmunologyVirusesMicrobial InteractionsMinireviewmedicine.drugVirus Physiological Phenomena
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Experimental Validation of Maximum Constant Boost Control and Switching Frequency Optimal for three-phase Quasi-Z-Source Converters

2020

This paper presents a modified modulation scheme for quasi-Z-Source converters, based on the Maximum Constant Boost Control (MCBC) concept and Switching Frequency Optimal (SFO) as reference signal. The effectiveness of the proposed technique is validated by comparing the obtained results (in terms of AC harmonic content and voltage stress) with those carried out from traditional modulation schemes. For this reason, a test bench has been assembled and the benefits of the SFO MCBC modulation scheme have been valuated.

voltage stressTest benchQuasi-Z-source InverterSettore ING-IND/32 - Convertitori Macchine E Azionamenti ElettriciConvertersSignalSettore ING-IND/31 - ElettrotecnicaharmonicThree-phaseModulationControl theorymodulation techniqueHarmonicsHarmonicharmonics modulation techniques Quasi-Z-source Inverter voltage stressMathematicsVoltage2020 2nd IEEE International Conference on Industrial Electronics for Sustainable Energy Systems (IESES)
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Decoupled control scheme of grid-connected split-source inverters

2017

Grid-connected power conversion systems for renewable energy sources must fulfill several requirements, e.g., the high efficiency, the reduced cost and complexity, and, quite often, the boost capabilities that is usually achieved using a front-end dc–dc boost converter before the inversion stage, leading to a two-stage architecture. Meanwhile, single-stage power conversion systems, which perform the boosting operation within the inversion one, offer some potential advantages, in terms of reducing the complexity and the volume of the whole system. Among several proposed options, the split-source inverter (SSI) has been recently proposed by Abdelhakim et al. as an alternative option with some…

voltage-source inverter (VSI)EngineeringDecoupled control; grid connected; impedance-based inverters; renewable energy sources (RESs); single-stage; space vector; split-source inverter (SSI); synchronous reference frame; voltage-source inverter (VSI); Z-source inverter (ZSI); Control and Systems Engineering; Electrical and Electronic Engineering020209 energyModulation index02 engineering and technologySettore ING-INF/01 - Elettronicasynchronous reference frameControl theoryspace vector0202 electrical engineering electronic engineering information engineeringElectronic engineeringElectrical and Electronic EngineeringMATLABcomputer.programming_languagesplit-source inverter (SSI)Z-source inverter Decoupled control Grid-connected Impedance-based inverters Renewable energy sources Single-stage Space vector Split-source inverter Synchronous reference frame Voltage source inverter Mathematical model Inverters Modulation Switches Voltage control Standards Topologybusiness.industry020208 electrical & electronic engineeringInversion (meteorology)Z-source inverter (ZSI)Gridsingle-stageDecoupled controlControl and Systems Engineeringimpedance-based invertersBoost converterrenewable energy sources (RESs)Invertergrid connectedReduced costbusinesscomputerReference frame
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