“…While insufficient capacity allocation may cause high WIP and long leadtimes, excess of capacity may result in idle resources due to the low levels of machine utilization (traffic intensity). Studies applying job-shop optimization models can be found in, e.g., Tirupati (1989a, 1989b), Boxma et al (1990), Kouvelis and Tirupati (1991), Schweitzer and Seidmann (1991), Van Vliet and Rinnooy Kan (1991), Bitran and Dasu (1992), Calabrese (1992), Sarkar (1994a, 1994b), Frenk et al (1994), Sundarraj et al (1994), Bretthauer (1996), Seshadri and Pinedo (1999), Bitran and Morabito (1999), Shanthikumar and Xu (2000), Souza and Ketzenberg (2002), Souza et al (2002aSouza et al ( , 2002b and Kouvelis et al (2005). For studies dealing with logistics and supply chains using queueing network models, the reader is referred to, e.g., Nakano and Ohno (1999), Warsing et al (2001) and Kerbache and Smith (2004).…”