Search results for "attenuation"

showing 3 items of 283 documents

The Industrial Applicability of PEA Space Charge Measurements, for Performance Optimization of HVDC Power Cables

2019

Cable manufacturing industries are constantly trying to improve the electrical performance of power cables. During the years, it was found that one of the most relevant degradation factors influencing the cable lifetime is the presence of space charge in the insulation layer. To detect the accumulated charge, the pulsed electro-acoustic (PEA) method is the most used technique. Despite the wide use of the PEA cell, several issues are still present. In particular, the PEA output signal is strongly disturbed by the acoustic waves reflections within the PEA cell. This causes the distortion of the output signal and therefore the misinterpretation of the charge profiles. This, in turn, may result…

space charge; PEA method; PEA cell model; IEEE Std 1732; space charge in cablespea methodControl and OptimizationMaterials science020209 energyAcousticsEnergy Engineering and Power Technology02 engineering and technologylcsh:Technology01 natural sciencesSignalpea cell modelieee std 1732Distortion0103 physical sciences0202 electrical engineering electronic engineering information engineeringspace charge in cablesElectrical and Electronic EngineeringEngineering (miscellaneous)010302 applied physicslcsh:TRenewable Energy Sustainability and the EnvironmentAttenuationHigh voltageAcoustic waveSpace chargePower (physics)Settore ING-IND/31 - ElettrotecnicaReflection (physics)space chargeEnergy (miscellaneous)Energies
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Tube transport of water vapor with condensation and desorption

2013

Attenuation and delay of active tracers in tube transport is an important current problem, but its full explanation is still lacking. To this end a model is introduced, where part of a tracer undergoes condensation and evaporation, treated as a diffusion-type process, in addition to Taylor dispersion. Condensation of water was verified by high-speed imaging, and the model solution fitted the breakthrough curves of laboratory measurements with pulses of water vapor of varying relative humidity. The model provides a transfer function whose performance was verified against field measurements. peerReviewed

ta114010504 meteorology & atmospheric sciencesPhysics and Astronomy (miscellaneous)ChemistryAttenuationTaylor dispersionCondensationAnalytical chemistryEvaporationMechanics01 natural sciences010305 fluids & plasmasDesorption0103 physical sciencesRelative humidityCurrent (fluid)Water vaporPhysics::Atmospheric and Oceanic Physics0105 earth and related environmental sciences
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INCIDENZA SULL’ANALISI DI RISCHIO DELLE MODALITÁ DI MISURA DEI SOIL GAS: IL CASO DI UN S.I.N. SICILIANO

2020

Il monitoraggio delle matrici aeriformi sta assumendo importanza crescente nell’ambito dei procedimenti di bonifica di siti contaminati, con riferimento sia all’esecuzione delle analisi di rischio, sia alla conseguente progettazione degli interventi di risanamento. L’utilizzo di misure dirette di campo si rivela di notevole interesse per la verifica di quelle indirette, ottenute con gli algoritmi implementati nei modelli matematici utilizzati per l’analisi di rischio. Obiettivo del lavoro presentato nella nota è stato quello di valutare l’influenza di misure dirette di soil gas e di flussi emissivi sull’analisi di rischio sanitaria. Come caso studio, si è considerato un S.I.N. nel territori…

volatile organic compoundsoil ganNatural attenuationSettore ICAR/03 - Ingegneria Sanitaria-AmbientaleDynamic flux chamberhealth risk assessment
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