“…Recently, scheduling problems with controllable machine speeds and job processing times have been considered by several researchers: Alidaee and Ahmadian (1993), Ishii et al (1987), Nowicki (1993), Nowicki and Zdrzalka (1988), Trick (1994), Van Vliet and Wagelmans (1990), Vickson (1980a,b), and Zdrzalka (1991). A survey of the literature can be found in Nowicki and Zdrzalka (1990).…”