Phase: RAMI3Total transmission through the medium at the lower boundary level
ftran for HET01_DIS_UNI_RED_20 testcase.
ftran for HET01_DIS_UNI_RED_50 testcase.
ftran for HET01_DIS_UNI_NIR_20 testcase.
ftran for HET01_DIS_UNI_NIR_50 testcase.