Optimization of vacuum belt drying process of Gardeniae Fructus in Reduning injection by Box-Behnken design-response surface methodology Multi-objective optimization of extraction process for red ginseng based upon extraction efficiency and cost control Optimization of solid lipid nanoparticles of silymarin by using Box-Behnken experimental design Optimization of solid lipid nanoparticles of silymarin by using Box-Behnken experimental design