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Estimation of the angle between ultrasound beam and blood velocity through the correlation functions
No full textCorrelation functions, calculated on the ultrasonic echoes scattered by blood, provide a rich harvest of information concerning the local speed, which has often been underestimated; in particular, blood flow measurement usually yields only the longitudinal component of the velocity, even if significant information about the speed direction can be extracted. In this paper it is shown how correlation functions, calculated on the dependency of both time and space displacements, allow us to evaluate the angle Θ between ultrasound beam and blood flow; when straight vessels are considered, this single parameter, combined with the longitudinal velocity profile, permits the complete hemodynamic characterization. The underlying theory is developed and preliminary experimental results are presente
Extreme ultraviolet imager for orbiting solar laboratory
No full textRapporto Agenzia Spaziale Italian
Valutazione dell’accuratezza statica dei convertitori analogico-digitale ad elevata risoluzione
No full textIl lavoro presenta un sistema realizzato su PC in grado di misurare e classificare gli errori di conversione in ADC commercialmente disponibili, permettendo di valutare il degrado delle prestazioni rispetto al comportamento ideale.
Vengono riportati infine i risultati ottenuti dall'analisi di due componenti commerciali a 14 e 16 bit
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