The dataset includes:

1. ivivc_ref_data.RData (.csv) - the dataset for estimating PK parameters; 
   it will generate ivivc_pk_values.Rdata after fitting --> solution/IR
   (it is not iv bolus.); weighting -> equal weight.
                          
2. ivivc_pk_values.RData - stored previously fitted PK parameters
   (kel, ka, and Vd); only 'kel' will be used later for ivivc modeling.

3. ivivc_test_data.Rdata (.csv) - the dataset includes in-vivo (conc.obs)
   and in-vitro (FRD, %) dataset all together; the dataset for in-vivo
   is only for "dosed once" for each dosage form. Thus, the dataset will 
   repeat for different pH dissolution profile (such as 1.2 & 6.8).
