Table 1.

Parameter choice for the simulation environment.

Parameter	Range	Optimal
Noise level (${\sigma }^2/$pixel in HU${}^2$)	2.5 $\times {10}^{-3}$–2.8 $\times {10}^{-3}$	2.5 $\times {10}^{-3}$
Number of projections	150–450	450