“…The vast majority of papers dealing with NPFS problems as their main contribution, present algorithms (meta-heuristics, in general) capable of handling them (Liao et al, 2006;Ying & Lin, 2007;Ying, 2008;Lin & Ying, 2009;Liao & Huang, 2010;Vahedi-Nouri et al, 2013;Ziaee, 2013;Rossi & Lanzetta, 2014;Benavides & Ritt 2016). These algorithms generally address the NPFS problem after a first phase in which it produces a near-optimal PFS solution: different types of procedures are applied to improve this initial PFS solution.…”