1. Dept. of Mechanical Eng., Ataturk University, Erzurum, Turkey
2. Dept. of Mechanical Eng., Erzurum Technical University, Erzurum, Turkey
3. Dept. of Mechanical Eng., Erzincan University, Erzincan, Turkey
4. EMYO, Atatürk Üniversity, Erzurum, Turkey