“…Unfortunately, it is often too difficult, or costly, to obtain enough good data to reliably estimate all of the unknown model parameters (e.g., Bagajewicz and Cabrera, 2003;Maria, 2004Maria, , 2006Mchaweh et al, 2004;Chang et al, 2005;Romdhane and Tizaoui, 2005;Wang et al, 2007). For complex models with many parameters, the resulting parameter estimates and model predictions may exhibit high variability, especially when the information content in the data available are limited, that is, the number of data points is small, measurements are noisy, the range of input-variable settings is small, and/or experimental designs are highly correlated (Wu et al, 2007). Consequently, decisions made using these models (or their parameter estimates) may be unreliable.…”