List of Articles . Design of experiments Open Access Article Abstract Page Full-Text 1 - Treatment of dairy effluent by ozonation: Design of experiments by response surface methodology Ali Mehrizad Akbar Hajipour Fahimeh Derakhshanfard Leila Amirkhany Open Access Article Abstract Page Full-Text 2 - Armentum: a hybrid direct search optimization methodology Francisco Zorrilla Briones Jaime Sa´nchez Leal Inocente Yuliana Mele´ndez Pastrana