Equidistant combination wavelength screening and step-by-step ph...

We applied near-infrared (NIR) spectroscopy with chemometrics for the rapid and reagent-free analysis of serum urea nitrogen (SUN). The modeling is based on the average effect of multiple sample partitions to achieve parameter selection with stability. A multiparameter optimization platform with Norris derivative filter–partial least squares (Norris-PLS) was developed to select the most suitable mode （d = 2, s = 33, g = 15）T. Using equidistant combination PLS (EC-PLS) with four parameters (initi