List of Articles Economic production quantity Open Access Article Abstract Page Full-Text 1 - A discrete particle swarm optimization algorithm with local search for a production-based two-echelon single-vendor multiple-buyer supply chain Mehdi Seifbarghy Masoud Mirzaei Kalani Mojtaba Hemmati Open Access Article Abstract Page Full-Text 2 - Optimal lot size of EPQ model considering imperfect and defective products S.R Hejazi J.C Tsou M Rasti Barzoki