Brury Jatmiko, Bambang Suhardi , Rahmaniyah Dwi Astuti ∗∗∗∗ ∗ Corespondence : E-mail : utan@uns.ac.id Keywords : productivity, experiments design, factorial design, response surface. Jurusan Teknik Industri, Universitas Sebelas Maret, Surakarta Performa (2005) Vol. 4, No.2: 117 - 126