We finally evaluate the results quantitatively. Table shows the similarity coefficients (Equation ) calculated for the peak images of C, O, and Si. The observed data has the lowest coefficients. The step-by-step solution by using KL-smooth-LR has the highest value compared to using the other smoothing techniques, especially for C. All of the coefficients calculated for O and Si were comparable. The similarity coefficients obtained by using the preliminary noise reduction techniques except for KL-smooth-LR were, at most, 0.86 for all parameters.