. Author manuscript; available in PMC: 2022 Mar 1.

Published in final edited form as: IEEE Trans Ultrason Ferroelectr Freq Control. 2021 Feb 25;68(3):389–405. doi: 10.1109/TUFFC.2020.2968147

TABLE III:

Mean, standard deviation and uniformity coefficient (i.e. CV = SD/MEAN) of the phase velocity and viscoelastic parameters μ₁ and μ₂, calculated for the TM phantoms within the ROI marked in Figs. 9 and 10.

Parameter	Unit	Phantom A		Phantom B
Parameter	Unit	Mean±SD	CV	Mean±SD	CV
V_ph, filters Off	[m/s]	2.44±0.13 (170 Hz)	0.05	1.43±0.13 (120 Hz)	0.09
V_ph, filters On	[m/s]	2.55±0.10 (170 Hz)	0.04	1.48±0.03 (120 Hz)	0.02
V_ph, filters Off	[m/s]	2.61±0.12 (350 Hz)	0.05	1.56±0.13 (260 Hz)	0.08
V_ph, filters On	[m/s]	2.72±0.06 (350 Hz)	0.02	1.58±0.05 (260 Hz)	0.03
V_ph, filters Off	[m/s]	5.22±4.92 (600 Hz)	0.94	3.83±4.87 (400 Hz)	1.27
V_ph, filters On	[m/s]	2.85±0.07 (600 Hz)	0.02	1.64±0.05 (400 Hz)	0.03
μ₁, LPVI^*	[kPa]	6.62±0.27	0.04	2.28±0.06	0.03
μ₁, $F_{2 D}$	[kPa]	5.96	-	2.08	-
μ₂, LPVI^*	[Pa·s]	1.23±0.11	0.09	0.52±0.08	0.15
μ₂, $F_{2 D}$	[Pa·s]	1.21	-	0.58	-

results for LPVI with adopted bandpass filters. LPVI without applying wavenumber and directional filters are not presented because, the nonlinear least-squares function was unable to solve this problem.