TABLE II.

The measured mean electron densities in unit of 10²³ e/cm³ for different contrast rods. The last column shows the overall RMSE.

	Aluminum	Acrylic	Delrin	Teflon	PMP	LDPE	Polystyrene	RMSE (%)
Actual electron density	7.83	3.83	4.56	6.24	2.85	3.16	3.34
Without noise suppression	7.81	3.82	4.40	5.91	2.86	3.15	3.33	0.91
PWLS-SBR	7.75	3.76	4.34	5.86	2.89	3.20	3.39	1.20
PWLS-EPR	8.86	3.75	4.29	5.70	2.98	3.24	3.38	2.21