The article introduced how to reduce quality cost by applying quality management theory and method to improve rate of qualified of resistors painting process in QC team activity.

Known from the theory of chaos, multi-fractal of stochastic process is a key characteristic of its dynamics, of which entropy rate is a special fractal dimension named information dimension.

Finally the key theorem of statistical learning theory based on random rough samples is proved, and the bounds on the rate of uniform convergence of learning process are discussed.